HomeMy WebLinkAboutCounty of Hawaii, Department of Water Supply - Water Use and Development Plan Update (2010)August 2010 FINAL REPORT
FUKUNAGA & ASSOCIATES, INC.
Consulting Engineers
1357 Kapiolani Boulevard, Suite 1530
Honolulu, Hawaii 96814
(808) 944-1821
Funded by the:
Department of Water Supply
For the:
County of Hawaii
HAWAII COUNTY WATER USE AND
DEVELOPMENT PLAN UPDATE
Hawaii Water Plan
ADDENDA
Page A-1
Hawaii County
Water Use and Development Plan Update
ADDENDUM NO. 1
The following modifications were made to the Water Use and Development Plan to address
comments received through the public hearings held on August 3 and 4, 2011 by the
Commission on Water Resource Management.
Page 1-17, Figure 1-6: Note added
Page 1-44, Table 1-10, 2nd data row: Data in first 4 columns revised
Page 801-41, Figure 801-9a: Arrows revised
Page 801-45, Figure 801-9b: Arrows revised
Page 803-28, Figure 803-9: Arrows revised
Page 804-26, Figure 804-9: Arrows revised
Page 809-23, Table 809-10, 1st data row: Data in first column revised
Page 809-23, Section 809.3.6.4, 2nd paragraph: Deleted and replaced with new paragraph
Page 809-43, Section 809.5.2.1.1.1, 2nd paragraph: Revised
Page 809-46, Section 809.5.3: New paragraph added after 1st paragraph
TABLE OF CONTENTS
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Hawaii County
Water Use and Development Plan Update
LIST OF ABBREVIATIONS.................................................................................................... xxix
EXECUTIVE SUMMARY .......................................................................................................ES-1
CHAPTER 1 INTRODUCTION...............................................................................................1-1
1.1 BACKGROUND.......................................................................................................1-1
1.1.1 State Water Code .....................................................................................1-1
1.1.2 History of Hawaii County Water Use and Development Plan ................1-1
1.1.3 Statewide Framework for the Update of the Hawaii Water Plan.............1-2
1.1.3.1 Ground Water Hydrologic Units........................................................1-2
1.1.3.1.1 Sustainable Yield...................................................................1-3
1.1.3.2 Surface Water Hydrologic Units........................................................1-4
1.1.4 The Hawaii Water Plan Update Status.....................................................1-7
1.2 PHYSICAL SETTING..............................................................................................1-8
1.2.1 Location and Size.....................................................................................1-8
1.2.2 Climate.....................................................................................................1-8
1.2.3 Geology..................................................................................................1-11
1.2.4 Hydrology..............................................................................................1-16
1.3 ECONOMY AND POPULATION..........................................................................1-19
1.3.1 Economy................................................................................................1-19
1.3.2 Population..............................................................................................1-20
1.4 LAND USE..............................................................................................................1-23
1.4.1 State Land Use.......................................................................................1-23
1.4.2 County General Plan..............................................................................1-23
1.4.3 County Zoning.......................................................................................1-27
1.4.4 Community Development Plans............................................................1-27
1.5 EXISTING WATER RESOURCES........................................................................1-28
1.5.1 General...................................................................................................1-28
1.5.2 Ground Water.........................................................................................1-28
1.5.2.1 Wells................................................................................................1-28
1.5.3 Surface Water.........................................................................................1-31
1.5.4 Rainwater Catchment.............................................................................1-37
1.5.5 Reclaimed Wastewater...........................................................................1-37
1.6 EXISTING WATER USE.......................................................................................1-38
1.6.1 General...................................................................................................1-38
1.6.2 Domestic Use.........................................................................................1-38
1.6.3 Industrial Use.........................................................................................1-41
1.6.4 Irrigation Use.........................................................................................1-41
1.6.5 Agricultural Use.....................................................................................1-41
1.6.6 Military Use...........................................................................................1-42
1.6.7 Municipal Use........................................................................................1-42
1.6.7.1 County Water Systems.....................................................................1-44
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1.6.7.2 State Water Systems ........................................................................1-44
1.6.7.3 Federal Water Systems ....................................................................1-44
1.6.7.4 Private Public Water Systems..........................................................1-45
1.6.8 Water Use by Resource..........................................................................1-45
1.6.8.1 Ground Water...................................................................................1-45
1.6.8.2 Surface Water...................................................................................1-49
1.6.8.2.1 Stream Diversions................................................................1-49
1.6.8.2.2 Instream Use........................................................................1-49
1.6.8.3 Rainwater Catchment.......................................................................1-50
1.6.8.4 Reclaimed Wastewater.....................................................................1-50
CHAPTER 2 TECHNICAL APPROACH.................................................................................2-1
2.1 WATER RESOURCES PLANNING METHODOLOGY........................................2-1
2.1.1 Full Build-Out Water Demand Projections..............................................2-4
2.1.1.1 Hawaii County General Plan .............................................................2-4
2.1.1.2 Hawaii County Zoning.......................................................................2-9
2.1.1.3 Refine Land Use Based Projection....................................................2-9
2.1.1.3.1 State Water Projects Plan.......................................................2-9
2.1.1.3.2 State Department of Hawaiian Home Lands .........................2-9
2.1.1.3.3 Agricultural Water Use and Development Plan...................2-10
2.1.2 5-Year Incremental Water Demand Projections to the Year 2025........2-10
2.1.2.1 Population and Growth Rate Projections.........................................2-11
2.1.3 Water Use Unit Rates.............................................................................2-11
2.1.3.1 Water System Standards..................................................................2-11
2.1.3.2 Water Consumption Data.................................................................2-12
2.1.4 DWS Historical Water Consumption Data Projection...........................2-12
2.2 RESOURCE AND FACILITY RECOMMENDATIONS......................................2-12
2.2.1 Water Source Adequacy ........................................................................2-12
2.2.1.1 Full Build-Out..................................................................................2-12
2.2.1.2 Twenty-Year Projection...................................................................2-13
2.2.2 Source Development Requirements.......................................................2-13
2.2.2.1 Supply-Side Management................................................................2-13
2.2.2.1.1 Conventional Water Resource Measures.............................2-13
2.2.2.1.2 Alternative Water Resource Enhancement Measures..........2-13
2.2.2.2 Demand-Side Management..............................................................2-14
2.2.2.2.1 Development Density Control.............................................2-14
2.2.2.2.2 Water Conservation .............................................................2-14
2.3 LIMITATIONS........................................................................................................2-15
2.3.1 Hawaii Water Plan Update.....................................................................2-15
2.3.2 Water Use Data......................................................................................2-15
2.3.3 CWRM Well and Pumpage Database....................................................2-16
2.3.4 CWRM Stream Diversion Database......................................................2-16
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CHAPTER 3 SECTOR REPORTS ...........................................................................................3-1
801 KOHALA AQUIFER SECTOR AREA......................................................................801-1
801.1 SECTOR AREA PROFILE...................................................................................801-1
801.1.1 General.................................................................................................801-1
801.1.2 Economy and Population.....................................................................801-1
801.1.2.1 Economy........................................................................................801-1
801.1.2.2 Population......................................................................................801-2
801.1.3 Land Use..............................................................................................801-2
801.1.3.1 Hawaii County General Plan .........................................................801-2
801.1.3.2 Hawaii County Zoning...................................................................801-5
801.2 EXISTING WATER RESOURCES......................................................................801-6
801.2.1 Ground Water.......................................................................................801-6
801.2.2 Surface Water.......................................................................................801-6
801.2.3 Reclaimed Wastewater.......................................................................801-15
801.3 EXISTING WATER USE...................................................................................801-15
801.3.1 General...............................................................................................801-15
801.3.2 Domestic Use.....................................................................................801-20
801.3.3 Industrial Use.....................................................................................801-20
801.3.4 Irrigation Use.....................................................................................801-20
801.3.5 Agricultural Use.................................................................................801-20
801.3.6 Military Use.......................................................................................801-20
801.3.7 Municipal Use....................................................................................801-20
801.3.7.1 County Water Systems.................................................................801-20
801.3.7.2 State Water Systems ....................................................................801-27
801.3.7.3 Federal Water Systems ................................................................801-28
801.3.7.4 Private Public Water Systems......................................................801-28
801.3.8 Water Use by Resource......................................................................801-28
801.3.8.1 Ground Water...............................................................................801-28
801.3.8.2 Surface Water...............................................................................801-29
801.3.8.3 Rainwater Catchment...................................................................801-29
801.3.8.4 Reclaimed Wastewater.................................................................801-29
801.4 FUTURE WATER NEEDS.................................................................................801-29
801.4.1 General...............................................................................................801-29
801.4.2 Full Build-Out Water Demand Projections........................................801-30
801.4.2.1 Refine Land Use Based Projection..............................................801-33
801.4.2.1.1 State Water Projects Plan.................................................801-33
801.4.2.1.2 State Department of Hawaiian Home Lands ...................801-34
801.4.2.1.3 Agricultural Water Use and Development Plan...............801-34
801.4.3 Water Use Unit Rates.........................................................................801-35
801.4.4 5-Year Incremental Water Demand Projection to the Year 2025......801-35
801.4.4.1 Kohala Aquifer Sector Area.........................................................801-35
801.4.4.2 Hawi Aquifer System Area [80101]............................................801-39
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801.4.4.3 Waimanu Aquifer System Area [80102].....................................801-43
801.4.4.4 Mahukona Aquifer System Area [80103]....................................801-47
801.4.5 DWS Historical Water Consumption Data Projections.....................801-50
801.5 RESOURCE AND FACILITY RECOMMENDATIONS..................................801-52
801.5.1 Water Source Adequacy ....................................................................801-52
801.5.1.1 Full Build-Out..............................................................................801-52
801.5.1.2 Twenty-Year Projection...............................................................801-52
801.5.2 Source Development Requirements...................................................801-52
801.5.2.1 Supply-Side Management............................................................801-52
801.5.2.1.1 Conventional Water Resource Measures.........................801-52
801.5.2.1.1.1 Ground Water.............................................................801-52
801.5.2.1.1.2 Surface Water.............................................................801-53
801.5.2.1.1.3 Water Transfer...........................................................801-53
801.5.2.1.2 Alternative Water Resource Enhancement Measures......801-54
801.5.2.1.2.1 Rainwater Catchment Systems ..................................801-54
801.5.2.1.2.2 Wastewater Reclamation ...........................................801-54
801.5.2.1.2.3 Desalination...............................................................801-54
801.5.2.2 Demand-Side Management..........................................................801-54
801.5.2.2.1 Development Density Control.........................................801-54
801.5.2.2.2 Water Conservation .........................................................801-55
801.5.3 Recommended Alternatives...............................................................801-55
802 EAST MAUNA KEA AQUIFER SECTOR AREA....................................................802-1
802.1 SECTOR AREA PROFILE...................................................................................802-1
802.1.1 General.................................................................................................802-1
802.1.2 Economy and Population.....................................................................802-1
802.1.2.1 Economy........................................................................................802-1
802.1.2.2 Population......................................................................................802-2
802.1.3 Land Use..............................................................................................802-2
802.1.3.1 Hawaii County General Plan .........................................................802-2
802.1.3.2 Hawaii County Zoning...................................................................802-5
802.2 EXISTING WATER RESOURCES......................................................................802-6
802.2.1 Ground Water.......................................................................................802-6
802.2.2 Surface Water.......................................................................................802-6
802.2.3 Reclaimed Wastewater.......................................................................802-13
802.3 EXISTING WATER USE...................................................................................802-13
802.3.1 General...............................................................................................802-13
802.3.2 Domestic Use.....................................................................................802-17
802.3.3 Industrial Use.....................................................................................802-17
802.3.4 Irrigation Use.....................................................................................802-17
802.3.5 Agricultural Use.................................................................................802-17
802.3.6 Military Use.......................................................................................802-17
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802.3.7 Municipal Use....................................................................................802-17
802.3.7.1 County Water Systems.................................................................802-18
802.3.7.2 State Water Systems ....................................................................802-20
802.3.7.3 Federal Water Systems ................................................................802-20
802.3.7.4 Private Public Water Systems......................................................802-20
802.3.8 Water Use by Resource......................................................................802-20
802.3.8.1 Ground Water...............................................................................802-20
802.3.8.2 Surface Water...............................................................................802-21
802.3.8.3 Rainwater Catchment...................................................................802-22
802.3.8.4 Reclaimed Wastewater.................................................................802-22
802.4 FUTURE WATER NEEDS.................................................................................802-22
802.4.1 General...............................................................................................802-22
802.4.2 Full Build-Out Water Demand Projections........................................802-23
802.4.2.1 Refine Land Use Based Projection..............................................802-23
802.4.2.1.1 State Water Projects Plan.................................................802-23
802.4.2.1.2 State Department of Hawaiian Home Lands ...................802-24
802.4.2.1.3 Agricultural Water Use and Development Plan...............802-25
802.4.3 Water Use Unit Rates.........................................................................802-25
802.4.4 5-Year Incremental Water Demand Projection to the Year 2025......802-25
802.4.5 DWS Historical Water Consumption Data Projections.....................802-28
802.5 RESOURCE AND FACILITY RECOMMENDATIONS..................................802-30
802.5.1 Water Source Adequacy ....................................................................802-30
802.5.1.1 Full Build-Out..............................................................................802-30
802.5.1.2 Twenty-Year Projection...............................................................802-30
802.5.2 Source Development Requirements...................................................802-30
802.5.2.1 Supply-Side Management............................................................802-30
802.5.2.1.1 Conventional Water Resource Measures.........................802-30
802.5.2.1.1.1 Ground Water.............................................................802-30
802.5.2.1.1.2 Surface Water.............................................................802-31
802.5.2.1.1.3 Water Transfer...........................................................802-31
802.5.2.1.2 Alternative Water Resource Enhancement Measures......802-31
802.5.2.1.2.1 Rainwater Catchment Systems ..................................802-31
802.5.2.1.2.2 Wastewater Reclamation ...........................................802-31
802.5.2.1.2.3 Desalination...............................................................802-31
802.5.2.2 Demand-Side Management..........................................................802-32
802.5.2.2.1 Development Density Control.........................................802-32
802.5.2.2.2 Water Conservation .........................................................802-32
802.5.3 Recommended Alternatives...............................................................802-32
803 WEST MAUNA KEA AQUIFER SECTOR AREA...................................................803-1
803.1 SECTOR AREA PROFILE...................................................................................803-1
803.1.1 General.................................................................................................803-1
803.1.2 Economy and Population.....................................................................803-1
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Water Use and Development Plan Update
803.1.2.1 Economy........................................................................................803-1
803.1.2.2 Population......................................................................................803-1
803.1.3 Land Use..............................................................................................803-2
803.1.3.1 Hawaii County General Plan .........................................................803-2
803.1.3.2 Hawaii County Zoning...................................................................803-5
803.2 EXISTING WATER RESOURCES......................................................................803-6
803.2.1 Ground Water.......................................................................................803-6
803.2.2 Surface Water.......................................................................................803-6
803.2.3 Reclaimed Wastewater.......................................................................803-13
803.3 EXISTING WATER USE...................................................................................803-14
803.3.1 General...............................................................................................803-14
803.3.2 Domestic Use.....................................................................................803-15
803.3.3 Industrial Use.....................................................................................803-15
803.3.4 Irrigation Use.....................................................................................803-15
803.3.5 Agricultural Use.................................................................................803-16
803.3.6 Military Use.......................................................................................803-16
803.3.7 Municipal Use....................................................................................803-16
803.3.7.1 County Water Systems.................................................................803-19
803.3.7.2 State Water Systems ....................................................................803-20
803.3.7.3 Federal Water Systems ................................................................803-21
803.3.7.4 Private Public Water Systems......................................................803-21
803.3.8 Water Use by Resource......................................................................803-21
803.3.8.1 Ground Water...............................................................................803-21
803.3.8.2 Surface Water...............................................................................803-22
803.3.8.3 Rainwater Catchment...................................................................803-22
803.3.8.4 Reclaimed Wastewater.................................................................803-22
803.4 FUTURE WATER NEEDS.................................................................................803-23
803.4.1 General...............................................................................................803-23
803.4.2 Full Build-Out Water Demand Projections........................................803-23
803.4.2.1 Refine Land Use Based Projection..............................................803-24
803.4.2.1.1 State Water Projects Plan.................................................803-24
803.4.2.1.2 State Department of Hawaiian Home Lands ...................803-25
803.4.2.1.3 Agricultural Water Use and Development Plan...............803-25
803.4.3 Water Use Unit Rates.........................................................................803-25
803.4.4 5-Year Incremental Water Demand Projection to the Year 2025......803-25
803.4.5 DWS Historical Water Consumption Data Projections.....................803-29
803.5 RESOURCE AND FACILITY RECOMMENDATIONS..................................803-31
803.5.1 Water Source Adequacy ....................................................................803-31
803.5.1.1 Full Build-Out..............................................................................803-31
803.5.1.2 Twenty-Year Projection...............................................................803-31
803.5.2 Source Development Requirements...................................................803-31
803.5.2.1 Supply-Side Management............................................................803-31
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803.5.2.1.1 Conventional Water Resource Measures.........................803-31
803.5.2.1.1.1 Ground Water.............................................................803-31
803.5.2.1.1.2 Surface Water.............................................................803-32
803.5.2.1.1.3 Water Transfer...........................................................803-32
803.5.2.1.2 Alternative Water Resource Enhancement Measures......803-32
803.5.2.1.2.1 Rainwater Catchment Systems ..................................803-32
803.5.2.1.2.2 Wastewater Reclamation ...........................................803-32
803.5.2.1.2.3 Desalination...............................................................803-33
803.5.2.2 Demand-Side Management..........................................................803-33
803.5.2.2.1 Development Density Control.........................................803-33
803.5.2.2.2 Water Conservation .........................................................803-33
803.5.3 Recommended Alternatives...............................................................803-34
804 NORTHEAST MAUNA LOA AQUIFER SECTOR AREA......................................804-1
804.1 SECTOR AREA PROFILE...................................................................................804-1
804.1.1 General.................................................................................................804-1
804.1.2 Economy and Population.....................................................................804-1
804.1.2.1 Economy........................................................................................804-1
804.1.2.2 Population......................................................................................804-2
804.1.3 Land Use..............................................................................................804-2
804.1.3.1 Hawaii County General Plan .........................................................804-2
804.1.3.2 Hawaii County Zoning...................................................................804-5
804.2 EXISTING WATER RESOURCES......................................................................804-6
804.2.1 Ground Water.......................................................................................804-6
804.2.2 Surface Water.......................................................................................804-6
804.2.3 Reclaimed Wastewater.......................................................................804-13
804.3 EXISTING WATER USE...................................................................................804-13
804.3.1 General...............................................................................................804-13
804.3.2 Domestic Use.....................................................................................804-17
804.3.3 Industrial Use.....................................................................................804-17
804.3.4 Irrigation Use.....................................................................................804-17
804.3.5 Agricultural Use.................................................................................804-17
804.3.6 Military Use.......................................................................................804-18
804.3.7 Municipal Use....................................................................................804-18
804.3.7.1 County Water Systems.................................................................804-18
804.3.7.2 State Water Systems ....................................................................804-19
804.3.7.3 Federal Water Systems ................................................................804-20
804.3.7.4 Private Public Water Systems......................................................804-20
804.3.8 Water Use by Resource......................................................................804-20
804.3.8.1 Ground Water...............................................................................804-20
804.3.8.2 Surface Water...............................................................................804-21
804.3.8.3 Rainwater Catchment...................................................................804-21
804.3.8.4 Reclaimed Wastewater.................................................................804-21
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804.4 FUTURE WATER NEEDS.................................................................................804-21
804.4.1 General...............................................................................................804-21
804.4.2 Full Build-Out Water Demand Projections........................................804-22
804.4.2.1 Refine Land Use Based Projection..............................................804-23
804.4.2.1.1 State Water Projects Plan.................................................804-23
804.4.2.1.2 State Department of Hawaiian Home Lands ...................804-23
804.4.2.1.3 Agricultural Water Use and Development Plan...............804-23
804.4.3 Water Use Unit Rates.........................................................................804-24
804.4.4 5-Year Incremental Water Demand Projection to the Year 2025......804-24
804.4.5 DWS Historical Water Consumption Data Projections.....................804-27
804.5 RESOURCE AND FACILITY RECOMMENDATIONS..................................804-29
804.5.1 Water Source Adequacy ....................................................................804-29
804.5.1.1 Full Build-Out..............................................................................804-29
804.5.1.2 Twenty-Year Projection...............................................................804-29
804.5.2 Source Development Requirements...................................................804-29
804.5.2.1 Supply-Side Management............................................................804-29
804.5.2.1.1 Conventional Water Resource Measures.........................804-29
804.5.2.1.1.1 Ground Water.............................................................804-29
804.5.2.1.1.2 Surface Water.............................................................804-29
804.5.2.1.1.3 Water Transfer...........................................................804-30
804.5.2.1.2 Alternative Water Resource Enhancement Measures......804-30
804.5.2.1.2.1 Rainwater Catchment Systems ..................................804-30
804.5.2.1.2.2 Wastewater Reclamation ...........................................804-30
804.5.2.1.2.3 Desalination...............................................................804-30
804.5.2.2 Demand-Side Management..........................................................804-30
804.5.2.2.1 Development Density Control.........................................804-30
804.5.2.2.2 Water Conservation .........................................................804-31
804.5.3 Recommended Alternatives...............................................................804-31
805 SOUTHEAST MAUNA LOA AQUIFER SECTOR AREA ......................................805-1
805.1 SECTOR AREA PROFILE...................................................................................805-1
805.1.1 General.................................................................................................805-1
805.1.2 Economy and Population.....................................................................805-1
805.1.2.1 Economy........................................................................................805-1
805.1.2.2 Population......................................................................................805-1
805.1.3 Land Use..............................................................................................805-2
805.1.3.1 Hawaii County General Plan .........................................................805-2
805.1.3.2 Hawaii County Zoning...................................................................805-5
805.2 EXISTING WATER RESOURCES......................................................................805-6
805.2.1 Ground Water.......................................................................................805-6
805.2.2 Surface Water.......................................................................................805-6
805.2.3 Reclaimed Wastewater.......................................................................805-13
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805.3 EXISTING WATER USE...................................................................................805-14
805.3.1 General...............................................................................................805-14
805.3.2 Domestic Use.....................................................................................805-15
805.3.3 Industrial Use.....................................................................................805-15
805.3.4 Irrigation Use.....................................................................................805-15
805.3.5 Agricultural Use.................................................................................805-16
805.3.6 Military Use.......................................................................................805-16
805.3.7 Municipal Use....................................................................................805-16
805.3.7.1 County Water Systems.................................................................805-16
805.3.7.2 State Water Systems ....................................................................805-19
805.3.7.3 Federal Water Systems ................................................................805-20
805.3.7.4 Private Public Water Systems......................................................805-20
805.3.8 Water Use by Resource......................................................................805-20
805.3.8.1 Ground Water...............................................................................805-20
805.3.8.2 Surface Water...............................................................................805-20
805.3.8.3 Rainwater Catchment...................................................................805-21
805.3.8.4 Reclaimed Wastewater.................................................................805-21
805.4 FUTURE WATER NEEDS.................................................................................805-21
805.4.1 General...............................................................................................805-21
805.4.2 Full Build-Out Water Demand Projections........................................805-22
805.4.2.1 Refine Land Use Based Projection..............................................805-22
805.4.2.1.1 State Water Projects Plan.................................................805-22
805.4.2.1.2 State Department of Hawaiian Home Lands ...................805-23
805.4.2.1.3 Agricultural Water Use and Development Plan...............805-23
805.4.3 Water Use Unit Rates.........................................................................805-23
805.4.4 5-Year Incremental Water Demand Projection to the Year 2025......805-24
805.4.5 DWS Historical Water Consumption Data Projections.....................805-27
805.5 RESOURCE AND FACILITY RECOMMENDATIONS..................................805-29
805.5.1 Water Source Adequacy ....................................................................805-29
805.5.1.1 Full Build-Out..............................................................................805-29
805.5.1.2 Twenty-Year Projection...............................................................805-29
805.5.2 Source Development Requirements...................................................805-29
805.5.2.1 Supply-Side Management............................................................805-29
805.5.2.1.1 Conventional Water Resource Measures.........................805-29
805.5.2.1.1.1 Ground Water.............................................................805-29
805.5.2.1.1.2 Surface Water.............................................................805-30
805.5.2.1.1.3 Water Transfer...........................................................805-30
805.5.2.1.2 Alternative Water Resource Enhancement Measures......805-30
805.5.2.1.2.1 Rainwater Catchment Systems ..................................805-30
805.5.2.1.2.2 Wastewater Reclamation ...........................................805-30
805.5.2.1.2.3 Desalination...............................................................805-30
805.5.2.2 Demand-Side Management..........................................................805-31
805.5.2.2.1 Development Density Control.........................................805-31
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805.5.2.2.2 Water Conservation .........................................................805-31
805.5.3 Recommended Alternatives...............................................................805-31
806 SOUTHWEST MAUNA LOA AQUIFER SECTOR AREA .....................................806-1
806.1 SECTOR AREA PROFILE...................................................................................806-1
806.1.1 General.................................................................................................806-1
806.1.2 Economy and Population.....................................................................806-1
806.1.2.1 Economy........................................................................................806-1
806.1.2.2 Population......................................................................................806-1
806.1.3 Land Use..............................................................................................806-2
806.1.3.1 Hawaii County General Plan .........................................................806-2
806.1.3.2 Hawaii County Zoning...................................................................806-5
806.2 EXISTING WATER RESOURCES......................................................................806-6
806.2.1 Ground Water.......................................................................................806-6
806.2.2 Surface Water.......................................................................................806-6
806.2.3 Reclaimed Wastewater.......................................................................806-13
806.3 EXISTING WATER USE...................................................................................806-13
806.3.1 General...............................................................................................806-13
806.3.2 Domestic Use.....................................................................................806-14
806.3.3 Industrial Use.....................................................................................806-14
806.3.4 Irrigation Use.....................................................................................806-14
806.3.5 Agricultural Use.................................................................................806-17
806.3.6 Military Use.......................................................................................806-17
806.3.7 Municipal Use....................................................................................806-17
806.3.7.1 County Water Systems.................................................................806-17
806.3.7.2 State Water Systems ....................................................................806-18
806.3.7.3 Federal Water Systems ................................................................806-18
806.3.7.4 Private Public Water Systems......................................................806-19
806.3.8 Water Use by Resource......................................................................806-19
806.3.8.1 Ground Water...............................................................................806-19
806.3.8.2 Surface Water...............................................................................806-19
806.3.8.3 Rainwater Catchment...................................................................806-19
806.3.8.4 Reclaimed Wastewater.................................................................806-20
806.4 FUTURE WATER NEEDS.................................................................................806-20
806.4.1 General...............................................................................................806-20
806.4.2 Full Build-Out Water Demand Projections........................................806-20
806.4.2.1 Refine Land Use Based Projection..............................................806-21
806.4.2.1.1 State Water Projects Plan.................................................806-21
806.4.2.1.2 State Department of Hawaiian Home Lands ...................806-22
806.4.2.1.3 Agricultural Water Use and Development Plan...............806-22
806.4.3 Water Use Unit Rates.........................................................................806-22
806.4.4 5-Year Incremental Water Demand Projection to the Year 2025......806-22
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806.4.5 DWS Historical Water Consumption Data Projections.....................806-26
806.5 RESOURCE AND FACILITY RECOMMENDATIONS..................................806-28
806.5.1 Water Source Adequacy ....................................................................806-28
806.5.1.1 Full Build-Out..............................................................................806-28
806.5.1.2 Twenty-Year Projection...............................................................806-28
806.5.2 Source Development Requirements...................................................806-28
806.5.2.1 Supply-Side Management............................................................806-28
806.5.2.1.1 Conventional Water Resource Measures.........................806-28
806.5.2.1.1.1 Ground Water.............................................................806-28
806.5.2.1.1.2 Surface Water.............................................................806-29
806.5.2.1.1.3 Water Transfer...........................................................806-29
806.5.2.1.2 Alternative Water Resource Enhancement Measures......806-29
806.5.2.1.2.1 Rainwater Catchment Systems ..................................806-29
806.5.2.1.2.2 Wastewater Reclamation ...........................................806-29
806.5.2.1.2.3 Desalination...............................................................806-30
806.5.2.2 Demand-Side Management..........................................................806-30
806.5.2.2.1 Development Density Control.........................................806-30
806.5.2.2.2 Water Conservation .........................................................806-30
806.5.3 Recommended Alternatives...............................................................806-30
807 NORTHWEST MAUNA LOA AQUIFER SECTOR AREA.....................................807-1
807.1 SECTOR AREA PROFILE...................................................................................807-1
807.1.1 General.................................................................................................807-1
807.1.2 Economy and Population.....................................................................807-1
807.1.2.1 Economy........................................................................................807-1
807.1.2.2 Population......................................................................................807-1
807.1.3 Land Use..............................................................................................807-2
807.1.3.1 Hawaii County General Plan .........................................................807-2
807.1.3.2 Hawaii County Zoning...................................................................807-5
807.2 AVAILABLE WATER RESOURCES.................................................................807-5
807.2.1 Ground Water.......................................................................................807-5
807.2.2 Surface Water.......................................................................................807-5
807.2.3 Reclaimed Wastewater.........................................................................807-6
807.3 EXISTING WATER USE.....................................................................................807-6
807.3.1 General.................................................................................................807-6
807.3.2 Domestic Use.....................................................................................807-13
807.3.3 Industrial Use.....................................................................................807-13
807.3.4 Irrigation Use.....................................................................................807-13
807.3.5 Agricultural Use.................................................................................807-14
807.3.6 Military Use.......................................................................................807-14
807.3.7 Municipal Use....................................................................................807-14
807.3.7.1 County Water Systems.................................................................807-14
807.3.7.2 State Water Systems ....................................................................807-17
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807.3.7.3 Federal Water Systems ................................................................807-18
807.3.7.4 Private Public Water Systems......................................................807-18
807.3.8 Water Use by Resource......................................................................807-18
807.3.8.1 Ground Water...............................................................................807-18
807.3.8.2 Surface Water...............................................................................807-18
807.3.8.3 Rainwater Catchment...................................................................807-18
807.3.8.4 Reclaimed Wastewater.................................................................807-19
807.4 FUTURE WATER NEEDS.................................................................................807-19
807.4.1 General...............................................................................................807-19
807.4.2 Full Build-Out Water Demand Projections........................................807-19
807.4.2.1 Refine Land Use Based Projection..............................................807-20
807.4.2.1.1 State Water Projects Plan.................................................807-20
807.4.2.1.2 State Department of Hawaiian Home Lands ...................807-20
807.4.2.1.3 Agricultural Water Use and Development Plan...............807-20
807.4.3 Water Use Unit Rates.........................................................................807-21
807.4.4 5-Year Incremental Water Demand Projection to the Year 2025......807-21
807.4.5 DWS Historical Water Consumption Data Projections.....................807-24
807.5 RESOURCE AND FACILITY RECOMMENDATIONS..................................807-26
807.5.1 Water Source Adequacy ....................................................................807-26
807.5.1.1 Full Build-Out..............................................................................807-26
807.5.1.2 Twenty-Year Projection...............................................................807-26
807.5.2 Source Development Requirements...................................................807-26
807.5.2.1 Supply-Side Management............................................................807-26
807.5.2.1.1 Conventional Water Resource Measures.........................807-26
807.5.2.1.1.1 Ground Water.............................................................807-26
807.5.2.1.1.2 Surface Water.............................................................807-26
807.5.2.1.1.3 Water Transfer...........................................................807-27
807.5.2.1.2 Alternative Water Resource Enhancement Measures......807-27
807.5.2.1.2.1 Rainwater Catchment Systems ..................................807-27
807.5.2.1.2.2 Wastewater Reclamation ...........................................807-27
807.5.2.1.2.3 Desalination...............................................................807-27
807.5.2.2 Demand-Side Management..........................................................807-27
807.5.2.2.1 Development Density Control.........................................807-27
807.5.2.2.2 Water Conservation .........................................................807-28
807.5.3 Recommended Alternatives...............................................................807-28
808 KILAUEA AQUIFER SECTOR AREA.....................................................................808-1
808.1 SECTOR AREA PROFILE...................................................................................808-1
808.1.1 General.................................................................................................808-1
808.1.2 Economy and Population.....................................................................808-1
808.1.2.1 Economy........................................................................................808-1
808.1.2.2 Population......................................................................................808-1
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808.1.3 Land Use..............................................................................................808-2
808.1.3.1 Hawaii County General Plan .........................................................808-2
808.1.3.2 Hawaii County Zoning...................................................................808-5
808.2 AVAILABLE WATER RESOURCES.................................................................808-5
808.2.1 Ground Water.......................................................................................808-5
808.2.2 Surface Water.......................................................................................808-6
808.2.3 Reclaimed Wastewater.........................................................................808-6
808.3 EXISTING WATER USE.....................................................................................808-6
808.3.1 General.................................................................................................808-6
808.3.2 Domestic Use.....................................................................................808-13
808.3.3 Industrial Use.....................................................................................808-14
808.3.4 Irrigation Use.....................................................................................808-14
808.3.5 Agricultural Use.................................................................................808-14
808.3.6 Military Use.......................................................................................808-14
808.3.7 Municipal Use....................................................................................808-14
808.3.7.1 County Water Systems.................................................................808-17
808.3.7.2 State Water Systems ....................................................................808-18
808.3.7.3 Federal Water Systems ................................................................808-18
808.3.7.4 Private Public Water Systems......................................................808-18
808.3.8 Water Use by Resource......................................................................808-19
808.3.8.1 Ground Water...............................................................................808-19
808.3.8.2 Surface Water...............................................................................808-19
808.3.8.3 Rainwater Catchment...................................................................808-19
808.3.8.4 Reclaimed Wastewater.................................................................808-20
808.4 FUTURE WATER NEEDS.................................................................................808-20
808.4.1 General...............................................................................................808-20
808.4.2 Full Build-Out Water Demand Projections........................................808-20
808.4.2.1 Refine Land Use Based Projection..............................................808-21
808.4.2.1.1 State Water Projects Plan.................................................808-21
808.4.2.1.2 State Department of Hawaiian Home Lands ...................808-22
808.4.2.1.3 Agricultural Water Use and Development Plan...............808-22
808.4.3 Water Use Unit Rates.........................................................................808-22
808.4.4 5-Year Incremental Water Demand Projection to the Year 2025......808-22
808.4.5 DWS Historical Water Consumption Data Projections.....................808-26
808.5 RESOURCE AND FACILITY RECOMMENDATIONS..................................808-28
808.5.1 Water Source Adequacy ....................................................................808-28
808.5.1.1 Full Build-Out..............................................................................808-28
808.5.1.2 Twenty-Year Projection...............................................................808-28
808.5.2 Source Development Requirements...................................................808-28
808.5.2.1 Supply-Side Management............................................................808-28
808.5.2.1.1 Conventional Water Resource Measures.........................808-28
808.5.2.1.1.1 Ground Water.............................................................808-28
808.5.2.1.1.2 Surface Water.............................................................808-29
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808.5.2.1.1.3 Water Transfer...........................................................808-29
808.5.2.1.2 Alternative Water Resource Enhancement Measures......808-29
808.5.2.1.2.1 Rainwater Catchment Systems ..................................808-29
808.5.2.1.2.2 Wastewater Reclamation ...........................................808-29
808.5.2.1.2.3 Desalination...............................................................808-29
808.5.2.2 Demand-Side Management..........................................................808-30
808.5.2.2.1 Development Density Control.........................................808-30
808.5.2.2.2 Water Conservation .........................................................808-30
808.5.3 Recommended Alternatives...............................................................808-30
809 HUALALAI AQUIFER SECTOR AREA ..................................................................809-1
809.1 SECTOR AREA PROFILE...................................................................................809-1
809.1.1 General.................................................................................................809-1
809.1.2 Economy and Population.....................................................................809-1
809.1.2.1 Economy........................................................................................809-1
809.1.2.2 Population......................................................................................809-1
809.1.3 Land Use..............................................................................................809-2
809.1.3.1 Hawaii County General Plan .........................................................809-2
809.1.3.2 Hawaii County Zoning...................................................................809-5
809.2 EXISTING WATER RESOURCES......................................................................809-6
809.2.1 Ground Water.......................................................................................809-6
809.2.2 Surface Water.....................................................................................809-11
809.2.3 Rainwater Catchment.........................................................................809-11
809.2.4 Reclaimed Wastewater.......................................................................809-11
809.3 EXISTING WATER USE...................................................................................809-12
809.3.1 General...............................................................................................809-12
809.3.2 Domestic Use.....................................................................................809-17
809.3.3 Industrial Use.....................................................................................809-18
809.3.4 Irrigation Use.....................................................................................809-18
809.3.5 Agricultural Use.................................................................................809-18
809.3.6 Municipal Use....................................................................................809-21
809.3.6.1 County Water Systems.................................................................809-21
809.3.6.2 State Water Systems ....................................................................809-22
809.3.6.3 Federal Water Systems ................................................................809-22
809.3.6.4 Private Public Water Systems......................................................809-23
809.3.7 Water Use by Resource......................................................................809-23
809.3.7.1 Ground Water...............................................................................809-23
809.3.7.2 Surface Water...............................................................................809-24
809.3.7.3 Rainwater Catchment...................................................................809-24
809.3.7.4 Reclaimed Wastewater.................................................................809-24
809.4 FUTURE WATER NEEDS.................................................................................809-24
809.4.1 General...............................................................................................809-24
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809.4.2 Full Build-Out Water Demand Projections........................................809-25
809.4.2.1 Refine Land Use Based Projection..............................................809-28
809.4.2.1.1 State Water Projects Plan.................................................809-28
809.4.2.1.2 State Department of Hawaiian Home Lands ...................809-28
809.4.2.1.3 Agricultural Water Use and Development Plan...............809-29
809.4.3 Water Use Unit Rates.........................................................................809-29
809.4.4 5-Year Incremental Water Demand Projections to the Year 2025....809-29
809.4.4.1 Hualalai Aquifer Sector Area.......................................................809-30
809.4.4.2 Keauhou Aquifer System Area [80901] ......................................809-34
809.4.4.3 Kiholo Aquifer System Area [80902]..........................................809-38
809.4.5 DWS Historical Water Consumption Data Projections.....................809-41
809.5 RESOURCE AND FACILITY RECOMMENDATIONS..................................809-43
809.5.1 Water Source Adequacy ....................................................................809-43
809.5.1.1 Full Build-Out..............................................................................809-43
809.5.1.2 Twenty-Year Projection...............................................................809-43
809.5.2 Source Development Requirements...................................................809-43
809.5.2.1 Supply-Side Management............................................................809-43
809.5.2.1.1 Conventional Water Resource Measures.........................809-43
809.5.2.1.1.1 Ground Water.............................................................809-43
809.5.2.1.1.2 Surface Water.............................................................809-44
809.5.2.1.1.3 Water Transfer...........................................................809-44
809.5.2.1.2 Alternative Water Resource Enhancement Measures......809-45
809.5.2.1.2.1 Rainwater Catchment Systems ..................................809-45
809.5.2.1.2.2 Wastewater Reclamation ...........................................809-45
809.5.2.1.2.3 Desalination...............................................................809-45
809.5.2.2 Demand-Side Management..........................................................809-45
809.5.2.2.1 Development Density Control.........................................809-45
809.5.2.2.2 Water Conservation .........................................................809-46
809.5.3 Recommended Alternatives...............................................................809-46
CHAPTER 4 SUMMARY OF CONCLUSIONS
AND GENERAL RECOMMENDATIONS........................................................4-1
LIST OF FIGURES, TABLES AND APPENDICES
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Water Use and Development Plan Update
FIGURES
Figure 1-1: Judicial Districts and Aquifer Boundaries.....................................................1-5
Figure 1-2: Surface Water Hydrologic Units....................................................................1-9
Figure 1-3: Volcanoes.....................................................................................................1-13
Figure 1-4: Simplified Geological Map..........................................................................1-14
Figure 1-5: The Water Cycle..........................................................................................1-16
Figure 1-6: Annual Rainfall............................................................................................1-17
Figure 1-7: Ground Water Quality & Location..............................................................1-21
Figure 1-8: Recoverable Groundwater by Wells & Tunnels..........................................1-22
Figure 1-9: State Land Use District Boundaries.............................................................1-25
Figure 1-10: Registered Wells..........................................................................................1-29
Figure 1-11: Surface Water Resources.............................................................................1-35
Figure 1-12: Water System Service Area Map.................................................................1-39
Figure 2-1: Full Build-Out Water Demand Projection Methodology...............................2-2
Figure 2-2: 5-Year Incremental Water Demand Projection Methodology.......................2-3
Figure 2-3: Theoretical Projected Demand.......................................................................2-4
Figure 2-4: General Plan Agricultural Designations and Surface Water Sources............2-7
Figure 2-5: Projected Demand H-M-L Growth Scenarios..............................................2-10
Figure 801-1: 2005 Revised General Plan LUPAG..........................................................801-3
Figure 801-2: County Zoning...........................................................................................801-7
Figure 801-3: Well and Tunnel Location .........................................................................801-9
Figure 801-4: Streams & Diversions..............................................................................801-11
Figure 801-5: Existing Water Use by Categories – Kohala Aquifer Sector Area..........801-16
Figure 801-5a: Existing Water Use by Categories – Hawi Aquifer System Area
[80101].....................................................................................................801-17
Figure 801-5b: Existing Water Use by Categories – Waimanu Aquifer System
Area [80102]............................................................................................801-18
Figure 801-5c: Existing Water Use by Categories – Mahukona Aquifer System
Area [80103]............................................................................................801-19
Figure 801-6: Water System and Service Area ..............................................................801-21
Figure 801-7: DWS Existing Water Use by Categories – Kohala Aquifer Sector
Area..........................................................................................................801-24
Figure 801-7a: DWS Existing Water Use by Categories – Hawi Aquifer System
Area [80101]............................................................................................801-25
Figure 801-7b: DWS Existing Water Use by Categories – Waimanu Aquifer
System Area [80102]...............................................................................801-26
Figure 801-7c: DWS Existing Water Use by Categories – Mahukona Aquifer
System Area [80103]...............................................................................801-27
Figure 801-8: Water Demand Projection Summary – Kohala Aquifer Sector Area......801-36
LIST OF FIGURES, TABLES AND APPENDICES
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Water Use and Development Plan Update
Figure 801-9: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Kohala Aquifer Sector Area ................................................801-37
Figure 801-10: Medium Growth Rate B Water Demand Projection by Category –
Kohala Aquifer Sector Area.....................................................................801-38
Figure 801-8a: Water Demand Projection Summary – Hawi Aquifer System Area
[80101].....................................................................................................801-40
Figure 801-9a: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Hawi Aquifer System Area [80101]....................................801-41
Figure 801-10a: Medium Growth Rate B Water Demand Projection by Category –
Hawi Aquifer System Area [80101]........................................................801-42
Figure 801-8b: Water Demand Projection Summary – Waimanu Aquifer System
Area [80102]............................................................................................801-44
Figure 801-9b: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Waimanu Aquifer System Area [80102].............................801-45
Figure 801-10b: Medium Growth Rate B Water Demand Projection by Category –
Waimanu Aquifer System Area [80102].................................................801-46
Figure 801-8c: Water Demand Projection Summary – Mahukona Aquifer System
Area [80103]............................................................................................801-47
Figure 801-9c: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Mahukona Aquifer System Area [80103]............................801-49
Figure 801-10c: Medium Growth Rate B Water Demand Projection by Category –
Mahukona Aquifer System Area [80103]................................................801-50
Figure 801-11: DWS Water Demand Projection – Kohala Aquifer Sector Area.............801-51
Figure 802-1: 2005 General Plan LUPAG .......................................................................802-3
Figure 802-2: County Zoning...........................................................................................802-7
Figure 802-3: Well and Tunnel Location .........................................................................802-9
Figure 802-4: Streams & Diversions..............................................................................802-11
Figure 802-5: Existing Water Use by Categories – East Mauna Kea Aquifer
Sector Area...............................................................................................802-14
Figure 802-6: Water System and Service Area ..............................................................802-15
Figure 802-7: DWS Existing Water Use by Categories – East Mauna Kea
Aquifer Sector Area.................................................................................802-20
Figure 802-8: Water Demand Projection Summary – East Mauna Kea Aquifer
Sector Area...............................................................................................802-26
Figure 802-9: Medium Growth Rate B Water Demand Projections and Full
Build-Out – East Mauna Kea Aquifer Sector Area .................................802-27
Figure 802-10: Medium Growth Rate B Water Demand Projection by Category –
East Mauna Kea Aquifer Sector Area......................................................802-28
Figure 802-11: DWS Water Demand Projection – East Mauna Kea Aquifer Sector
Area..........................................................................................................802-29
Figure 803-1: 2005 Revised General Plan LUPAG..........................................................803-3
LIST OF FIGURES, TABLES AND APPENDICES
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Figure 803-2: County Zoning...........................................................................................803-7
Figure 803-3: Well and Tunnel Location .........................................................................803-9
Figure 803-4: Streams & Diversions..............................................................................803-11
Figure 803-5: Existing Water Use by Categories – West Mauna Kea Aquifer
Sector Area...............................................................................................803-15
Figure 803-6: Water System and Service Area ..............................................................803-17
Figure 803-7: DWS Existing Water Use by Categories – West Mauna Kea
Aquifer Sector Area.................................................................................803-20
Figure 803-8: Water Demand Projection Summary – West Mauna Kea Aquifer
Sector Area...............................................................................................803-27
Figure 803-9: Medium Growth Rate B Water Demand Projections and Full
Build-Out – West Mauna Kea Aquifer Sector Area................................803-28
Figure 803-10: Medium Growth Rate B Water Demand Projection by Category –
West Mauna Kea Aquifer Sector Area ....................................................803-29
Figure 803-11: DWS Water Demand Projection – West Mauna Kea Aquifer
Sector Area...............................................................................................803-30
Figure 804-1: 2005 Revised General Plan LUPAG..........................................................804-3
Figure 804-2: County Zoning...........................................................................................804-7
Figure 804-3 Well and Tunnel Location .........................................................................804-9
Figure 804-4 Streams & Diversions..............................................................................804-11
Figure 804-5: Existing Water Use by Categories – Northeast Mauna Loa Aquifer
Sector Area...............................................................................................804-14
Figure 804-6: Water System and Service Area ..............................................................804-15
Figure 804-7: DWS Existing Water Use by Categories – Northeast Mauna Loa
Aquifer Sector Area.................................................................................804-19
Figure 804-8: Water Demand Projection Summary – Northeast Mauna Loa
Aquifer Sector Area.................................................................................804-25
Figure 804-9: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Northeast Mauna Loa Aquifer Sector Area.........................804-26
Figure 804-10: Medium Growth Rate B Water Demand Projection by Category –
Northeast Mauna Loa Aquifer Sector Area.............................................804-27
Figure 804-11: DWS Water Demand Projection – Northeast Mauna Loa Aquifer
Sector Area...............................................................................................804-28
Figure 805-1: 2005 Revised General Plan LUPAG..........................................................805-3
Figure 805-2: County Zoning...........................................................................................805-7
Figure 805-3: Well and Tunnel Location .........................................................................805-9
Figure 805-4: Streams & Diversions..............................................................................805-11
Figure 805-5: Existing Water Use by Categories – Southeast Mauna Loa Aquifer
Sector Area...............................................................................................805-15
Figure 805-6: Water System and Service Area ..............................................................805-17
LIST OF FIGURES, TABLES AND APPENDICES
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Figure 805-7: DWS Existing Water Use by Categories – Southeast Mauna Loa
Aquifer Sector Area.................................................................................805-19
Figure 805-8: Water Demand Projection Summary – Southeast Mauna Loa
Aquifer Sector Area.................................................................................805-25
Figure 805-9: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Southeast Mauna Loa Aquifer Sector Area.........................805-26
Figure 805-10: Medium Growth Rate B Water Demand Projection by Category –
Southeast Mauna Loa Aquifer Sector Area.............................................805-27
Figure 805-11: DWS Water Demand Projection – Southeast Mauna Loa Aquifer
Sector Area...............................................................................................805-28
Figure 806-1: 2005 Revised General Plan LUPAG..........................................................806-3
Figure 806-2: County Zoning...........................................................................................806-7
Figure 806-3: Well and Tunnel Location .........................................................................806-9
Figure 806-4: Streams & Diversions..............................................................................806-11
Figure 806-5: Existing Water Use by Categories – Southwest Mauna Loa Aquifer
Sector Area...............................................................................................806-14
Figure 806-7: DWS Existing Water Use by Categories – Southwest Mauna Loa
Aquifer Sector Area.................................................................................806-18
Figure 806-8: Water Demand Projection Summary – Southwest Mauna Loa
Aquifer Sector Area.................................................................................806-23
Figure 806-9: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Southwest Mauna Loa Aquifer Sector Area........................806-25
Figure 806-10: Medium Growth Rate B Water Demand Projection by Category –
Southwest Mauna Loa Aquifer Sector Area............................................806-26
Figure 806-11: DWS Water Demand Projection – Southwest Mauna Loa Aquifer
Sector Area...............................................................................................806-27
Figure 807-1: 2005 Revised General Plan LUPAG..........................................................807-3
Figure 807-2: County Zoning...........................................................................................807-7
Figure 807-3: Well and Tunnel Location .........................................................................807-9
Figure 807-4: Streams & Diversions..............................................................................807-11
Figure 807-5: Existing Water Use by Categories – Northwest Mauna Loa Aquifer
Sector Area...............................................................................................807-13
Figure 807-6: Water System and Service Area ..............................................................807-15
Figure 807-7: DWS Existing Water Use by Categories – Northwest Mauna Loa
Aquifer Sector Area.................................................................................807-17
Figure 807-8: Water Demand Projection Summary – Northwest Mauna Loa
Aquifer Sector Area.................................................................................807-22
Figure 807-9: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Northwest Mauna Loa Aquifer Sector Area........................807-23
Figure 807-10: Medium Growth Rate B Water Demand Projection by Category –
Northwest Mauna Loa Aquifer Sector Area............................................807-24
LIST OF FIGURES, TABLES AND APPENDICES
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Figure 807-11: DWS Water Demand Projection – Northwest Mauna Loa Aquifer
Sector Area...............................................................................................807-25
Figure 808-1: 2005 Revised General Plan LUPAG..........................................................808-3
Figure 808-2: County Zoning...........................................................................................808-7
Figure 808-3: Well and Tunnel Location .........................................................................808-9
Figure 808-4: Streams & Diversions..............................................................................808-11
Figure 808-5: Existing Water Use by Categories – Kilauea Aquifer Sector Area.........808-13
Figure 808-6: Water System and Service Area ..............................................................808-15
Figure 808-7: DWS Existing Water Use by Categories – Kilauea Aquifer Sector
Area..........................................................................................................808-18
Figure 808-8: Water Demand Projection Summary – Kilauea Aquifer Sector
Area..........................................................................................................808-23
Figure 808-9: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Kilauea Aquifer Sector Area ...............................................808-25
Figure 808-10: Medium Growth Rate B Water Demand Projection by Category –
Kilauea Aquifer Sector Area....................................................................808-26
Figure 808-11: DWS Water Demand Projection – Kilauea Aquifer Sector Area............808-27
Figure 809-1: 2005 Revised General Plan LUPAG..........................................................809-3
Figure 809-2: County Zoning...........................................................................................809-7
Figure 809-3: Well Location.............................................................................................809-9
Figure 809-4: Streams & Diversions..............................................................................809-13
Figure 809-5: Existing Water Use by Categories – Hualalai Aquifer Sector Area........809-15
Figure 809-5a: Existing Water Use by Categories – Keauhou Aquifer System Area
[80901].....................................................................................................809-16
Figure 809-5b: Existing Water Use by Categories – Kiholo Aquifer System Area
[80902].....................................................................................................809-17
Figure 809-6: Water System and Service Area ..............................................................809-19
Figure 809-7: DWS Existing Water Use by Categories – Hualalai Aquifer Sector
Area..........................................................................................................809-22
Figure 809-8: Water Demand Projection Summary – Hualalai Aquifer Sector
Area..........................................................................................................809-30
Figure 809-9: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Hualalai Aquifer Sector Area ..............................................809-32
Figure 809-10: Medium Growth Rate B Water Demand Projection by Category –
Hualalai Aquifer Sector Area...................................................................809-33
Figure 809-8a: Water Demand Projection Summary – Keauhou Aquifer System
Area [80901]............................................................................................809-34
Figure 809-9a: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Keauhou Aquifer System Area [80901]..............................809-36
LIST OF FIGURES, TABLES AND APPENDICES
Page
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Hawaii County
Water Use and Development Plan Update
Figure 809-10a: Medium Growth Rate B Water Demand Projection by Category –
Keauhou Aquifer System Area [80901] ..................................................809-37
Figure 809-8b: Water Demand Projection Summary – Kiholo Aquifer System
Area [80902]............................................................................................809-38
Figure 809-9b: Medium Growth Rate B Water Demand Projections and Full
Build-Out – Kiholo Aquifer System Area [80902]..................................809-40
Figure 809-10b: Medium Growth Rate B Water Demand Projection by Category –
Kiholo Aquifer System Area [80902]......................................................809-41
Figure 809-11: DWS Water Demand Projection – Hualalai Aquifer Sector Area...........809-42
TABLES
Table 1-1: Aquifer Sector Areas......................................................................................1-4
Table 1-2: Stratigraphic Rock Units in the Island of Hawaii........................................1-15
Table 1-3: County General Plan Population Projection................................................1-23
Table 1-4: State Land Use Classification......................................................................1-23
Table 1-5: General Plan Land Use Pattern Allocation Guide .......................................1-24
Table 1-6: County Zoning.............................................................................................1-27
Table 1-7: Summary of Installed Pumps in Existing Well Sources..............................1-31
Table 1-8: Gaging Records............................................................................................1-32
Table 1-9: Reclaimed Wastewater Resources...............................................................1-37
Table 1-10: Water Systems .............................................................................................1-43
Table 1-11: Well Production and Sustainable Yield.......................................................1-47
Table 1-12: Major Stream Diversions.............................................................................1-49
Table 2-1: Proposed Urban Expansion Density Rates ....................................................2-5
Table 2-2: Water System Standards, Domestic Consumption Guidelines....................2-11
Table 801-1: Historical Population .................................................................................801-2
Table 801-2: Population Projection.................................................................................801-2
Table 801-3: LUPAG Map Estimated Land Use Allocation Acreage – Kohala
Aquifer Sector Area...................................................................................801-5
Table 801-4: County Zoning Estimated Class Allocation Acreage – Kohala
Aquifer Sector Area...................................................................................801-6
Table 801-5: Stream Diversions – Kohala Aquifer Sector Area...................................801-13
Table 801-6: Existing Water Use by Categories – Kohala Aquifer Sector Area..........801-16
Table 801-6a: Existing Water Use by Categories – Hawi Aquifer System Area
[80101].....................................................................................................801-17
Table 801-6b: Existing Water Use by Categories – Waimanu Aquifer System
Area [80102]............................................................................................801-18
Table 801-6c: Existing Water Use by Categories – Mahukona Aquifer System
Area [80103]............................................................................................801-19
LIST OF FIGURES, TABLES AND APPENDICES
Page
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Hawaii County
Water Use and Development Plan Update
Table 801-7: DWS Existing Water Use by Categories – Kohala Aquifer Sector
Area..........................................................................................................801-24
Table 801-7a: DWS Existing Water Use by Categories – Hawi Aquifer System
Area [80101]............................................................................................801-25
Table 801-7b: DWS Existing Water Use by Categories – Waimanu Aquifer
System Area [80102]...............................................................................801-26
Table 801-7c: DWS Existing Water Use by Categories – Mahukona Aquifer
System Area [80103]...............................................................................801-27
Table 801-8: Sustainable Yield – Kohala Aquifer Sector Area....................................801-28
Table 801-9: Summary of Demand Projections............................................................801-29
Table 801-10: Hawaii County General Plan Full Build-Out Water Demand
Projection – Kohala Aquifer Sector Area................................................801-30
Table 801-11: County Zoning Full Build-Out Water Demand Projection – Kohala
Aquifer Sector Area.................................................................................801-30
Table 801-10a: Hawaii County General Plan Full Build-Out Water Demand
Projection – Hawi Aquifer System Area [80101]....................................801-31
Table 801-11a: County Zoning Full Build-Out Water Demand Projection – Hawi
Aquifer System Area [80101]..................................................................801-31
Table 801-10b: Hawaii County General Plan Full Build-Out Water Demand
Projection – Waimanu Aquifer System Area [80102].............................801-32
Table 801-11b: County Zoning Full Build-Out Water Demand Projection –
Waimanu Aquifer System Area [80102].................................................801-32
Table 801-10c: Hawaii County General Plan Full Build-Out Water Demand
Projection – Mahukona Aquifer System Area [80103] ...........................801-33
Table 801-11c: County Zoning Full Build-Out Water Demand Projection –
Mahukona Aquifer System Area [80103]................................................801-33
Table 801-12: Future State Water Projects to Generate Significant Demands...............801-34
Table 801-13: Water Demand Projection – Kohala Aquifer Sector Area.......................801-35
Table 801-14: Medium Growth Rate B Water Demand Projection by Category –
Kohala Aquifer Sector Area.....................................................................801-36
Table 801-13a: Water Demand Projection – Hawi Aquifer System Area [80101] ..........801-39
Table 801-14a: Medium Growth Rate B Water Demand Projection by Category –
Hawi Aquifer System Area [80101]........................................................801-40
Table 801-13b: Water Demand Projection – Waimanu Aquifer System Area
[80102].....................................................................................................801-43
Table 801-14b: Medium Growth Rate B Water Demand Projection by Category –
Waimanu Aquifer System Area [80102].................................................801-44
Table 801-13c: Water Demand Projection – Mahukona Aquifer System Area
[80103].....................................................................................................801-47
Table 801-14c: Medium Growth Rate B Water Demand Projection by Category –
Mahukona Aquifer System Area [80103]................................................801-48
LIST OF FIGURES, TABLES AND APPENDICES
Page
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Hawaii County
Water Use and Development Plan Update
Table 802-1: Historical Population .................................................................................802-2
Table 802-2: Population Projection.................................................................................802-2
Table 802-4: County Zoning Estimated Class Allocation Acreage – East Mauna
Kea Aquifer Sector Area............................................................................802-6
Table 802-5: Stream Diversions – East Mauna Kea Aquifer Sector Area....................802-13
Table 802-6: Existing Water Use by Categories – East Mauna Kea Aquifer
Sector Area...............................................................................................802-14
Table 802-7: DWS Existing Water Use by Categories – East Mauna Kea
Aquifer Sector Area.................................................................................802-19
Table 802-8: Sustainable Yield – East Mauna Kea Aquifer Sector Area.....................802-21
Table 802-9: Spring Sources – East Mauna Kea Aquifer Sector Area .........................802-21
Table 802-10: Summary of Demand Projections............................................................802-22
Table 802-11 Hawaii County General Plan Full Build-Out Water Demand
Projection – East Mauna Kea Aquifer Sector Area.................................802-23
Table 802-12: Zoning Full Build-Out Water Demand Projection – East Mauna
Kea Aquifer Sector Area..........................................................................802-23
Table 802-13: Water Demand Projection – East Mauna Kea Aquifer Sector Area........802-25
Table 802-14: Medium Growth Rate B Water Demand Projection by Category –
East Mauna Kea Aquifer Sector Area......................................................802-26
Table 803-1: Historical Population .................................................................................803-2
Table 803-2: Population Projection.................................................................................803-2
Table 803-3: LUPAG Map Estimated Land Use Allocation Acreage – West
Mauna Kea Aquifer Sector Area................................................................803-5
Table 803-4: County Zoning Estimated Class Allocation Acreage – West Mauna
Kea Aquifer Sector Area............................................................................803-6
Table 803-5: Stream Diversions – West Mauna Kea Aquifer Sector Area...................803-13
Table 803-6: Wastewater Reclamation Facilities – West Mauna Kea Aquifer
Sector Area...............................................................................................803-13
Table 803-7: Existing Water Use by Categories – West Mauna Kea Aquifer
Sector Area...............................................................................................803-14
Table 803-8: Private Irrigation Well Pumpage .............................................................803-16
Table 803-9: DWS Existing Water Use by Categories – West Mauna Kea
Aquifer Sector Area.................................................................................803-20
Table 803-10: Private Public Water System Water Use – West Mauna Kea
Aquifer Sector Area.................................................................................803-21
Table 803-11: Sustainable Yield – West Mauna Kea Aquifer Sector Area....................803-22
Table 803-12: Summary of Demand Projections............................................................803-23
Table 803-13: Hawaii County General Plan Full Build-Out Water Demand
Projection – West Mauna Kea Aquifer Sector Area................................803-24
Table 803-14: County Zoning Full Build-Out Water Demand Projection – West
Mauna Kea Aquifer Sector Area..............................................................803-24
Table 803-15: Future State Water Projects to Generate Significant Demands...............803-25
LIST OF FIGURES, TABLES AND APPENDICES
Page
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Hawaii County
Water Use and Development Plan Update
Table 803-16: Water Demand Projection – West Mauna Kea Aquifer Sector Area.......803-26
Table 803-17: Medium Growth Rate B Water Demand Projection by Category –
West Mauna Kea Aquifer Sector Area ....................................................803-27
Table 804-1: Historical Population .................................................................................804-2
Table 804-2: Population Projection.................................................................................804-2
Table 804-3: LUPAG Map Estimated Land Use Allocation Acreage – Northeast
Mauna Loa Aquifer Sector Area................................................................804-5
Table 804-4: County Zoning Estimated Class Allocation Acreage – Northeast
Mauna Loa Aquifer Sector Area................................................................804-6
Table 804-5: Stream Diversions – Northeast Mauna Loa Aquifer Sector Area............804-13
Table 804-6: Existing Water Use by Categories – Northeast Mauna Loa Aquifer
Sector Area...............................................................................................804-14
Table 804-7: DWS Existing Water Use by Categories – Northeast Mauna Loa
Aquifer Sector Area.................................................................................804-19
Table 804-8: Sustainable Yield – Northeast Mauna Loa Aquifer Sector Area.............804-20
Table 804-9: Summary of Demand Projections............................................................804-21
Table 804-10: Hawaii County General Plan Full Build-Out Water Demand
Projection – Northeast Mauna Loa Aquifer Sector Area.........................804-22
Table 804-11: County Zoning Full Build-Out Water Demand Projection –
Northeast Mauna Loa Aquifer Sector Area.............................................804-22
Table 804-12: Future State Water Projects to Generate Significant Demands...............804-23
Table 804-13: Water Demand Projection – Northeast Mauna Loa Aquifer Sector
Area..........................................................................................................804-24
Table 804-14: Medium Growth Rate B Water Demand Projection by Category –
Northeast Mauna Loa Aquifer Sector Area.............................................804-25
Table 805-1: Historical Population .................................................................................805-2
Table 805-2: Population Projection.................................................................................805-2
Table 805-3: LUPAG Map Estimated Land Use Allocation Acreage – Southeast
Mauna Loa Aquifer Sector Area................................................................805-5
Table 805-4: County Zoning Estimated Class Allocation Acreage – Southeast
Mauna Loa Aquifer Sector Area................................................................805-6
Table 805-5: Stream Diversions – Southeast Mauna Loa Aquifer Sector Area............805-13
Table 805-6: Wastewater Reclamation Facilities – Southeast Mauna Loa
Aquifer Sector Area.................................................................................805-13
Table 805-7: Existing Water Use by Categories – Southeast Mauna Loa Aquifer
Sector Area...............................................................................................805-14
Table 805-8: DWS Existing Water Use by Categories – Southeast Mauna Loa
Aquifer Sector Area.................................................................................805-19
Table 805-9: Sustainable Yield – Southeast Mauna Loa Aquifer Sector Area.............805-20
Table 805-10: Summary of Demand Projections............................................................805-21
LIST OF FIGURES, TABLES AND APPENDICES
Page
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Hawaii County
Water Use and Development Plan Update
Table 805-11: Hawaii County General Plan Full Build-Out Water Demand
Projection – Southeast Mauna Loa Aquifer Sector Area.........................805-22
Table 805-12: County Zoning Full Build-Out Water Demand Projection –
Southeast Mauna Loa Aquifer Sector Area.............................................805-22
Table 805-13: Future State Water Projects to Generate Significant Demands...............805-23
Table 805-14: Water Demand Projection – Southeast Mauna Loa Aquifer Sector
Area..........................................................................................................805-24
Table 805-15: Medium Growth Rate B Water Demand Projection by Category –
Southeast Mauna Loa Aquifer Sector Area.............................................805-25
Table 806-1: Historical Population .................................................................................806-2
Table 806-2: Population Projection.................................................................................806-2
Table 806-3: LUPAG Map Estimated Land Use Allocation Acreage Southwest
Mauna Loa Aquifer Sector Area................................................................806-5
Table 806-4: County Zoning Estimated Class Allocation Acreage – Southwest
Mauna Loa Aquifer Sector Area................................................................806-6
Table 806-5: Stream Diversions – Southwest Mauna Loa Aquifer Sector Area ..........806-13
Table 806-6: Existing Water Use by Categories – Southwest Mauna Loa Aquifer
Sector Area...............................................................................................806-13
Table 806-7: Private Irrigation Well Pumpage .............................................................806-17
Table 806-8: DWS Existing Water Use by Categories – Southwest Mauna Loa
Aquifer Sector Area.................................................................................806-18
Table 806-9: Sustainable Yield – Southwest Mauna Loa Aquifer Sector Area............806-19
Table 806-10: Summary of Demand Projections............................................................806-20
Table 806-11: Hawaii County General Plan Full Build-Out Water Demand
Projection – Southwest Mauna Loa Aquifer Sector Area........................806-21
Table 806-12: County Zoning Full Build-Out Water Demand Projection –
Southwest Mauna Loa Aquifer Sector Area............................................806-21
Table 806-13: Future State Water Projects to Generate Significant Demands...............806-22
Table 806-14: Water Demand Projection – Southwest Mauna Loa Aquifer Sector
Area..........................................................................................................806-23
Table 806-15: Medium Growth Rate B Water Demand Projection by Category –
Southwest Mauna Loa Aquifer Sector Area............................................806-24
Table 807-1: Historical Population .................................................................................807-2
Table 807-2: Population Projection.................................................................................807-2
Table 807-3: LUPAG Map Estimated Land Use Allocation Acreage – Northwest
Mauna Loa Aquifer Sector Area................................................................807-2
Table 807-4: County Zoning Estimated Class Allocation Acreage – Northwest
Mauna Loa Aquifer Sector Area................................................................807-5
Table 807-5: Wastewater Reclamation Facilities – Northwest Mauna Loa
Aquifer Sector Area...................................................................................807-6
LIST OF FIGURES, TABLES AND APPENDICES
Page
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Hawaii County
Water Use and Development Plan Update
Table 807-6: Existing Water Use by Categories – Northwest Mauna Loa Aquifer
Sector Area.................................................................................................807-6
Table 807-7: Private Irrigation Well Pumpage .............................................................807-14
Table 807-8: DWS Existing Water Use by Categories – Northwest Mauna Loa
Aquifer Sector Area.................................................................................807-17
Talbe 807-9: Sustainable Yield – Northwest Mauna Loa Aquifer Sector Area............807-18
Table 807-10: Summary of Demand Projections............................................................807-19
Table 807-11: Hawaii County General Plan Full Build-Out Water Demand
Projection – Northwest Mauna Loa Aquifer Sector Area........................807-20
Table 807-12: County Zoning Full Build-Out Water Demand Projection –
Northwest Mauna Loa Aquifer Sector Area............................................807-20
Table 807-13: Water Demand Projection – Northwest Mauna Loa Aquifer Sector
Area..........................................................................................................807-21
Table 807-14: Medium Growth Rate B Water Demand Projection by Category –
Northwest Mauna Loa Aquifer Sector Area............................................807-22
Table 808-1: Historical Population .................................................................................808-2
Table 808-2: Population Projection.................................................................................808-2
Table 808-3: LUPAG Map Estimated Land Use Allocation Acreage – Kilauea
Aquifer Sector Area...................................................................................808-2
Table 808-4: County Zoning Estimated Class Allocation Acreage – Kilauea
Aquifer Sector Area...................................................................................808-5
Table 808-5: Stream Diversions – Kilauea Aquifer Sector Area....................................808-6
Table 808-6: Existing Water Use by Categories – Kilauea Aquifer Sector Area.........808-13
Table 808-7: DWS Existing Water Use by Categories – Kilauea Aquifer Sector
Area..........................................................................................................808-17
Table 808-8: Sustainable Yield – Kilauea Aquifer Sector Area ...................................808-19
Table 808-9: Summary of Demand Projections............................................................808-20
Table 808-10: Hawaii County General Plan Full Build-Out Water Demand
Projection – Kilauea Aquifer Sector Area...............................................808-21
Table 808-11: County Zoning Full Build-Out Water Demand Projection –
Kilauea Aquifer Sector Area....................................................................808-21
Table 808-12: Future State Water Projects to Generate Significant Demands...............808-22
Table 808-13: Water Demand Projection – Kilauea Aquifer Sector Area......................808-23
Table 808-14: Medium Growth Rate B Water Demand Projection by Category –
Kilauea Aquifer Sector Area....................................................................808-24
Table 809-1: Historical Population .................................................................................809-2
Table 809-2: Population Projection.................................................................................809-2
Table 809-3: LUPAG Map Estimated Land Use Allocation Acreage – Hualalai
Aquifer Sector Area...................................................................................809-5
LIST OF FIGURES, TABLES AND APPENDICES
Page
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Hawaii County
Water Use and Development Plan Update
Table 809-4: County Zoning Estimated Class Allocation Acreage – Hualalai
Aquifer Sector Area...................................................................................809-6
Table 809-5: Stream Diversions – Hualalai Aquifer Sector Area.................................809-11
Table 809-6: Wastewater Reclamation Facilities – Hualalai Aquifer Sector Area.......809-12
Table 809-7: Existing Water Use by Categories – Hualalai Aquifer Sector Area........809-15
Table 809-7a: Existing Water Use by Categories – Keauhou Aquifer System Area
[80901].....................................................................................................809-16
Table 809-7b: Existing Water Use by Categories – Kiholo Aquifer System Area
[80902].....................................................................................................809-17
Table 809-8: Private Irrigation Well Pumpage – Hualalai Aquifer Sector Area ..........809-18
Table 809-9: DWS Existing Water Use by Categories – Hualalai Aquifer Sector
Area..........................................................................................................809-22
Table 809-10: Private Public Water System Water Use – Hualalai Aquifer Sector
Area..........................................................................................................809-23
Table 809-11: Sustainable Yield and Pumpage – Hualalai Aquifer Sector Area............809-24
Table 809-12: Summary of Demand Projections............................................................809-25
Table 809-13: Hawaii County General Plan Full Build-Out Water Demand
Projection – Hualalai Aquifer Sector Area..............................................809-25
Table 809-14: County Zoning Full Build-Out Water Demand Projection –
Hualalai Aquifer Sector Area...................................................................809-26
Table 809-13a: Hawaii County General Plan Full Build-Out Water Demand
Projection – Keauhou Aquifer System Area [80901]..............................809-26
Table 809-14a: County Zoning Full Build-Out Water Demand Projection –
Keauhou Aquifer System Area [80901] ..................................................809-27
Table 809-13b: Hawaii County General Plan Full Build-Out Water Demand
Projection – Kiholo Aquifer System Area [80902].................................809-27
Table 809-14b: County Zoning Full Build-Out Water Demand Projection – Kiholo
Aquifer System Area [80902]..................................................................809-28
Table 809-15: Future State Water Projects to Generate Significant Demands...............809-28
Table 809-16: Water Demand Projection – Hualalai Aquifer Sector Area.....................809-30
Table 809-17: Medium Growth Rate B Water Demand Projection by Category –
Hualalai Aquifer Sector Area...................................................................809-31
Table 809-16a: Water Demand Projection – Keauhou Aquifer System Area
[80901].....................................................................................................809-34
Table 809-17a: Medium Growth Rate B Water Demand Projection by Category –
Keauhou Aquifer System Area [80901] ..................................................809-35
Table 809-16b: Water Demand Projection – Kiholo Aquifer System Area [80902]........809-38
Table 809-17b: Medium Growth Rate B Water Demand Projection by Category –
Kiholo Aquifer System Area [80902]......................................................809-39
REFERENCES ............................................................................................................................R-1
APPENDICES
LIST OF FIGURES, TABLES AND APPENDICES
Page
Page xxviii
Hawaii County
Water Use and Development Plan Update
APPENDIX A: County of Hawaii, General Plan 2005, Goals and Policies
APPENDIX B: CWRM Island of Hawaii Well Database (as of October 2005)
APPENDIX C Description of the County of Hawaii Department of Water Supply
LIST OF ABBREVIATIONS
Page xxix
Hawaii County
Water Use and Development Plan Update
LIST OF ABBREVIATIONS
ARMD State of Hawaii, Department of Agriculture, Agricultural Resource
Management Division
ASEA Aquifer Sector Area
ASYA Aquifer System Area
AWUDP Agricultural Water Use and Development Plan
CDP Community Development Plan
CWRM Commission on Water Resource Management
DHHL State of Hawaii, Department of Hawaiian Home Lands
DLNR State of Hawaii, Department of Land and Natural Resources
DOA State of Hawaii, Department of Agriculture
DOH State of Hawaii, Department of Health
DOT State of Hawaii, Department of Transportation
DPS State of Hawaii, Department of Public Safety
DWS County of Hawaii, Department of Water Supply
GIS Geographic Information Systems
GP County of Hawaii, General Plan
GPD gallons per day
HCDC State of Hawaii, Housing and Community Development Corporation
HELCO Hawaiian Electric Light Company, Inc.
HSA Hawaii Stream Assessment
KSBE Kamehameha Schools Bishop Estate
LHD Lower Hamakua Ditch
LUPAG Land Use Pattern Allocation Guide
MAV Moving Average
MG million gallons
MGD million gallons per day
NELHA National Energy Laboratory of Hawaii Authority
PGV Puna Geothermal Venture
PRV Pressure Reducing Valve
PTA Pohakuloa Military Training Area
SDWA Safe Drinking Water Act
SKWIS South Kona Watershed Irrigation Study
SLH Session Laws of Hawaii
SWPP State Water Projects Plan
SY Sustainable Yield
USDA, NASS United States Department of Agriculture, National Agricultural Statistics
Service
LIST OF ABBREVIATIONS
Page xxx
Hawaii County
Water Use and Development Plan Update
LIST OF ABBREVIATIONS
USGS United States Geological Survey
WQP Water Quality Plan
WRPP Water Resource Protection Plan
WS Water System
WUDP Water Use and Development Plan
WWRF Wastewater Reclamation Facility
EXECUTIVE SUMMARY
Page ES-1
Hawaii County
Water Use and Development Plan Update
ES EXECUTIVE SUMMARY
ES.1 INTRODUCTION
In 1987, the State Legislature passed the State Water Code (Hawaii Revised Statutes, Chapter
174C) to protect Hawaii’s surface and ground water resources, which called for the
establishment of a Commission on Water Resource Management (CWRM) and the formulation
of a Hawaii Water Plan that would serve as a dynamic, long-range planning guide for the
Commission. The Hawaii Water Plan consists of five parts: (1) the Water Resource Protection
Plan, (2) the Water Quality Plan, (3) the State Water Projects Plan, (4) the Agricultural Water
Use and Development Plan (AWUDP), and (5) the County Water Use and Development Plans
(WUDP). A separate WUDP is to be prepared by each of the four Counties.
In compliance with the State Water Code, the County of Hawaii Department of Water Supply
(DWS) was tasked with the responsibility to prepare the County of Hawaii Water Use and
Development Plan in 1988. The WUDP serves as a continuing long-range guide for the water
resource development in the County. Its objective is “to set forth the allocation of water to land
use through the development of policies and strategies which shall guide the County in its
planning, management, and development of water resources to meet projected demands.”
Section 13-170-31, Hawaii Administrative Rules states that the WUDP shall include but not be
limited to:
(1) Status of water and related land development including an inventory of existing water
uses for domestic, municipal, and industrial users, agriculture, aquaculture,
hydropower development, drainage, reuse, reclamation, recharge, and resulting
problems and constraints;
(2) Future land uses and related water needs; and
(3) Regional plans for water developments including recommended and alternative
plans, costs, adequacy of plans, and relationship to the water resource protection and
water quality plans.
The original County of Hawaii WUDP was adopted by the County Council by ordinance on May
10, 1990, and was conditionally accepted by the CWRM for incorporation into the Hawaii Water
Plan on June 27, 1990, with the provisions that the WUDP be reviewed and revised as necessary
by the County to coincide with the review process of the Hawaii Water Plan.
The Statewide Framework for Updating the Hawaii Water Plan (Framework) dated February
2000 was created by the CWRM to facilitate coordination, integration, and consistency of the
components of the Hawaii Water Plan. In addition, the framework is a guide for preparation of
the WUDP to insure effective implementation by the County and utilization by the CWRM for
resource management purposes.
The Framework requires data and analyses to be based on ground water and surface water
hydrologic units designated by the CWRM. However, the surface water hydrologic units were
only recently established and adopted in June 2005; and additional information on the surface
Executive Summary
Page ES-2
Hawaii County
Water Use and Development Plan Update
water hydrologic units is extremely limited. Therefore, the Hawaii WUDP update is based on
the ground water hydrologic units, and references the surface water hydrologic units as
applicable. There are nine Aquifer Sector Areas on the island of Hawaii, which are further
subdivided into Aquifer System Areas. Figure ES-1 shows the aquifer areas and indicates the
Sustainable Yield, or safe source capacity, established by the Water Resource Protection Plan
(WRPP).
Sustainable Yield (SY) is defined and described in the Water Resource Protection Plan (WRPP)
as follows:
Sustainable yield refers to the forced withdrawal rate of groundwater that could
be sustained indefinitely without affecting either the quality of the pumped water
or the volume rate of pumping. It depends upon the head selected as the minimum
allowable during continuous pumping. Head is the elevation [or height] of the
unconfined water table above sea level. There is not a unique value for
sustainable yield; the value depends on the head that will preserve the integrity of
the groundwater resource at the level decided upon by the manager.
Sustainable yield is equal to a fraction of the recharge. In a basal lens the
fraction is usually more than half and sometimes greater than three fourths where
initial heads are high. In high level aquifers about three fourths of the recharge
can be taken as sustainable yield.
[Groundwater recharge is the process of adding water to the aquifer through the
infiltration of precipitation on the land surface.]
The estimates of sustainable yield are not meant to be an exact number which
could be used in final planning documents. The estimates are constrained not only
by the scanty data base but also by the fact that they do not consider the
feasibility of developing the groundwater. The estimates should not be equated to
developable groundwater. In many regions, taking advantage of a high estimate
would not be economically feasible.
ES.2 METHODOLOGY
Each Aquifer Sector Area is evaluated with the following methodology.
ES.2.1 Existing Water Resources
Water resources that currently are utilized on the island are examined within each sector area.
These resources include the following:
Groundwater
Surface water
Rainwater catchment
Reclaimed wastewater
CapeKumukahi
Ka Lae
Honaunau
Kailua
Hilo
Kawaihae
Kiholo Bay
Ookala
Upolu Point
ANAEHOOMALU
WAIMEA
MAHUKONA
HAWI
WAIMANU
HONOKAA
PAAUILO
HAKALAU
ONOMEA
HILO
KEAAU
PAHOA
KALAPANA
HILINA
KEAIWA
OLAA
KAPAPALA
NAALEHU
KALAE
MANUKA
KAAPUNA
KEALAKEKUA
KIHOLO
KEAUHOU
Hawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLAN
Job No. 2003-818
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
27 MGD / 80101
110 MGD / 80102
31 MGD / 8020117 MGD / 80103
24 MGD / 80301
60 MGD / 80202
150 MGD / 80203
147 MGD / 80204
347 MGD / 80401
393 MGD / 80402
435 MGD / 80801
157 MGD / 80802
9 MGD / 80803
17 MGD / 80804
117 MGD / 80503
19 MGD / 80502
124 MGD / 80501
31 MGD / 80504
42 MGD / 80601
50 MGD / 80602
38 MGD / 80603
30 MGD / 80701
18 MGD / 80902
38 MGD / 80901
KOHALA154 MGD / 801
E. MAUNA KEA388 MGD / 802
W. MAUNA KEA24 MGD / 803
N.W. MAUNA LOA30 MGD / 807
HUALALAI56 MGD / 809
N.E. MAUNA LOA740 MGD / 804
KILAUEA618 MGD / 808
S.E. MAUNA LOA291 MGD / 805
S.W. MAUNA LOA130 MGD / 806
0 10 20 305
Miles
FIGURE ES-1
AQUIFER BOUNDARIES
HYDROLOGIC UNITSSustainable Yield / Aquifer CodeTOTAL = 2431 MGD
AQUIFER SECTOR AREASAQUIFER SYSTEM AREAS
LEGEND
Island of Hawaii
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Hawaii County
Water Use and Development Plan Update
ES.2.2 Existing Water Use
Existing water use is calculated based on available data, including well pumpage reported to the
CWRM, water purveyor records, Department of Health records, and available GIS data.
ES.2.2.1 Existing Water Use by CWRM Categories
Existing water use is categorized to the extent possible according to preliminary water use
categories recently established by CWRM staff. Future WUDP Updates should conform to the
finalized water use categories to the extent possible. Water use is assigned to a single category
to avoid overlap and confusion.
Domestic (Individual Household)
Industrial (Fire Protection, Mining, Thermoelectric Cooling, Geothermal)
Irrigation (Golf Course, Hotel, Landscape, Parks, School, Dust Control)
Agriculture (Aquatic Plants & Animals, Crops/Processing, Livestock & Pasture,
Ornamental/Nursery)
Military
Municipal (County, State, Private Public Water Systems [as defined by DOH])
ES.2.2.2 Existing Water Use by Resource
Existing water use is also categorized according to the four water resources listed previously.
ES.2.3 Future Water Needs
Water resource planning for the Hawaii WUDP update considers both land use based water
demand projections and rate of population growth to plan for future water needs. A distinct
difference between the scenarios is that the land use based projections are based on planning
level standards, while the 20-year projections are based on actual consumption.
ES.2.3.1 Full Build-Out Water Demand Projections
The full build-out water demand projections are land use based. The County General Plan Land
Use Pattern Allocation Guide (LUPAG) and County Zoning Land Use classifications are
assessed to estimate the projected development densities for each designation at full-build out.
The results are used to project the ultimate water demand based on the General Plan, and
potential water demand based on land use zoning, which is legally developable, to determine if
there are adequate water resources to sustain the land uses.
As required by the Framework, the WUDP considers the most recent State Water Projects Plan,
and Agricultural Water Use and Development Plan forecasts if water requirements are available;
and recognizes the current and future development needs of the Department of Hawaiian Home
Lands.
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Hawaii County
Water Use and Development Plan Update
ES.2.3.2 5-Year Incremental Water Demand Projections to the Year 2025
Existing population and water use were calculated as the basis of the water demand projections
to the year 2025 to assess the adequacy of current and near-term water sources (20 years).
Population and growth rate projections were applied in 5-year increments for the next 20 years;
and have high-growth, medium-growth (base case) and low-growth (the most conservative)
scenarios. The demands are further differentiated into potable and nonpotable demands.
ES.2.4 Water Use Unit Rates
Water use unit rates were based on the Water System Standards as listed in Table ES-1 and
actual consumption data. Potable and non-potable water requirements were differentiated where
appropriate.
Table ES-1: Water System Standards, Domestic Consumption Guidelines
Zoning Designation Average Daily Demand
RESIDENTIAL:
Single Family or Duplex
Multi-Family Low Rise
Multi-Family High Rise
400 gals/unit
400 gals/unit
400 gals/unit
COMMERCIAL:
Commercial Only
3000 gals/acre
RESORT: 400 gals/unit or 17,000 gal/acre*
LIGHT INDUSTRY: 4000 gals/acre
SCHOOLS, PARKS: 4000 gals/acre or 60 gals/student
AGRICULTURE: 3400 gals/acre**
* Resort ADD of 17,000 gal/acre based on ADD for Maui.
** Agriculture ADD based on AWUDP.
Water use unit rates based on actual consumption data for specific geographic regions were
developed by the Hawaii County Department of Water Supply for single family residential
units, as listed below:
South Kohala and North Kona – 2.5 units/lot
South Kona – 1.5 units/lot
Elsewhere – 400 gals/unit
These unit rates result in higher water demand projections as compared to the Water System
Standard unit rates, but are viewed as more realistic based on historic consumption data.
ES.2.5 Agricultural Water Use
Agricultural water use is extremely difficult to determine due to the lack of available data. The
proposed methodology to determine agricultural water use was met with strong objection at
Executive Summary
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Hawaii County
Water Use and Development Plan Update
public meetings. Overwhelmingly, public input suggested that the need for irrigation water was
not predicated on the classification of Agricultural lands. Public input further suggested that
agricultural users would grow what is feasible according to the climate, and that irrigation from
groundwater sources would be minimal. For example, crops requiring large amounts of moisture
would be grown in areas that have a higher ambient rainfall. For these reasons, and because it is
expected that the next update to the AWUDP will investigate these issues in greater detail, two
agricultural water use scenarios are presented for each of the full build-out scenarios (Hawaii
County General Plan and Hawaii County Zoning) and the 5-year incremental water demand
projection scenario. This identifies a range of agricultural water use, which considers the best
and worst case scenarios on an interim basis, until the next phase of the AWUDP is complete.
ES.2.6 Resource and Facility Recommendations
Several water resource enhancement measures were examined to meet the projected water
demands. These include conventional supply-side measures such as groundwater and surface
water development, alternative supply-side measures such as development of rainwater
catchment systems, reclaimed wastewater, and desalination; and demand-side management such
as development density control and water conservation measures. The feasibility of these water
resource enhancement options was compared to provide a recommended combination of
measures.
ES.2.7 Aquifer Sector Area Synopses
A brief synopsis of each Aquifer Sector Area follows.
Executive Summary
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Hawaii County
Water Use and Development Plan Update
801 – Kohala Aquifer Sector Area
Ground water and surface water are plentiful in the Kohala Aquifer Sector Area, and these may
continue as the primary sources of water. Specifically, high-level groundwater could be
developed for potable water sources, and the island’s four major ditch systems could be restored
to satisfy non-potable needs. Including worst-case agricultural demands, full development to the
maximum densities of LUPAG and County Zoning are not sustainable within the Kohala Aquifer
Sector Area and the Hawi and Mahukona Aquifer System Areas. Without agricultural water
demands, the LUPAG and County Zoning scenarios are sustainable within the Kohala Aquifer
Sector Area; however, LUPAG maximum density build-out cannot be sustained within the
Mahukona Aquifer System Area. This can be mitigated by transfer of water between aquifer
system areas, although the projected 20-year demands indicate that this will not be necessary in
the near future. Potential shortages of water in adjacent aquifer sector areas can also be
addressed through transfer of water from the Kohala Aquifer Sector Area, which will likely
necessitate infrastructure upgrades.
0
50
100
150
200
250
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
SY = 154
LUPAG = 40–208
Zoning = 9–174
N-P: Nonpotable
Executive Summary
Page ES-9
Hawaii County
Water Use and Development Plan Update
802 – East Mauna Kea Aquifer Sector Area
Ground water and surface water are present in great abundance in the sector area. However, if
worst-case agricultural demands are included, the land use full build-out scenarios are close to
the sustainable yield. Excluding agricultural demands, the current, 20-year projected, and land
use full build-out demands are well below the sustainable yield; therefore, groundwater may be
developed as the primary source of potable water. Spring sources used to provide potable water
may be replaced by groundwater sources if it is more beneficial and economical than to comply
with Federal Safe Drinking Water Act requirements.
0
50
100
150
200
250
300
350
400
450
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
SY = 388
LUPAG = 25–405Zoning = 8–378
N-P: Nonpotable
Executive Summary
Page ES-10
Hawaii County
Water Use and Development Plan Update
803 – West Mauna Kea Aquifer Sector Area
The sector area encompasses part of the Kohala Coast, including one of the island’s three luxury
resort complexes (Mauna Kea Resort). Not surprisingly, current water usage is high, nearly one-
third of the sector area’s sustainable yield. Full build-out to LUPAG maximum density is not
sustainable. Full development to the maximum density of County Zoning is sustainable if
agricultural demands are excluded, and is not sustainable if worst-case agricultural demands are
included. Twenty-year projected demands range between 60 and 80 percent of the sustainable
yield. For these reasons, water resource planning for the sector area is important. Development
of basal potable water resources should proceed with caution, and the feasibility for water
transfer from the adjoining Kohala Aquifer Sector Area should be examined. Water
conservation should be a primary focus in the sector area, and utilizing the highest quality water
for the highest end use should be promoted. It would be prudent to irrigate primarily with non-
potable sources, and take measures to encourage reduction of potable water usage by residential
customers closer to average island water usage.
0
20
40
60
80
100
120
140
160
180
200
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
SY = 24
LUPAG = 52–187
Zoning = 14–151
N-P: Nonpotable
Executive Summary
Page ES-11
Hawaii County
Water Use and Development Plan Update
804 – Northeast Mauna Loa Aquifer Sector Area
Encompassing the Urban Hilo area, this sector area has the highest current water usage on the
island. Due to the high annual rainfall, it also has the island’s highest sustainable yield, which
can easily sustain the LUPAG and Zoning maximum density full build-out demands, even if
worst-case agricultural demands are included. Development of groundwater sources may
continue as land development demands dictate. The recommendation for this sector area is to
improve the efficiency of the DWS Hilo Water System; loss of source water through leakage is
suspected. The detriment is the excess cost of production, not loss of a limited supply of sources.
0
100
200
300
400
500
600
700
800
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
SY = 740
LUPAG = 119–203
Zoning = 26–107 N-P: Nonpotable
Executive Summary
Page ES-12
Hawaii County
Water Use and Development Plan Update
805 – Southeast Mauna Loa Aquifer Sector Area
This sector area is sparsely populated. If agricultural demands are excluded, it has the lowest
current water usage, the lowest 20-year projected usage, and the lowest full build-out projected
demands of all sector areas on the island; all of these are a small fraction of the sector area’s
sustainable yield. If worst case agricultural demands are included, the land use full build-out
scenarios require approximately half of the sustainable yield. Deep groundwater wells may be
developed to suit anticipated development that would require potable water. Groundwater
sources may also replace existing tunnel and spring sources, which are influenced by surface
water, if costs to comply with DOH regulations are excessive. Formerly used by the sugar
plantation, tunnel and spring sources are numerous, and should be examined as a potential
resource to supply non-potable demands, both in the Southeast Mauna Loa Aquifer Sector Area
and the adjacent Southwest Mauna Loa Aquifer Sector Area.
0
50
100
150
200
250
300
350
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
SY = 291
LUPAG = 14–159Zoning = 4–148 N-P: Nonpotable
Executive Summary
Page ES-13
Hawaii County
Water Use and Development Plan Update
806 – Southwest Mauna Loa Aquifer Sector Area
Current water usage, 20-year projected usage, and full build-out LUPAG and County Zoning
maximum density demands within the sector area are a small fraction of its sustainable yield if
agricultural demands are not included. If worst-case agricultural demands are included, the
LUPAG full build-out demand exceeds the sustainable yield, and the Zoning demand is nearly
95 percent of the sustainable yield. Surface water sources are extremely limited, and due to the
limited availability of basal groundwater, high level groundwater is expected to be the primary
water resource. The challenge in this sector area is transmission, particularly to areas which are
currently supplied by individual rainwater catchments and water hauling. Previous studies have
proposed several alternative measures to supply both potable and non-potable water. These
alternatives should be further evaluated and compared.
0
20
40
60
80
100
120
140
160
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
SY = 130
LUPAG = 18–143
Zoning = 1–123
N-P: Nonpotable
Executive Summary
Page ES-14
Hawaii County
Water Use and Development Plan Update
807 – Northwest Mauna Loa Aquifer Sector Area
Two of the island’s three luxury resort complexes along the Kohala Coast (Mauna Lani Resort
and Waikaloa Resort) are located within the sector area. Existing development demands are over
one-quarter of the sustainable yield, and 20-year projected demands will amount to nearly half of
the sustainable yield. Full build-out to the maximum density of LUPAG is not sustainable, with
and without worst-case agricultural demands. Full build-out to the Zoning maximum density
requires 30 to 60 percent of the sustainable yield. Because there are no potable water sources in
the sector area, and minimal potential for significant future development of potable sources, a
proper balance of water transfer from other aquifer sector areas and water conservation must be
achieved. The relative compactness of the two major resort developments increases the
possibility of combining non-potable sources into a water system to satisfy the non-potable
needs. Wastewater reclamation should be continued. Demand-side conservation programs
should be implemented by the potable water purveyors to reduce the average water usage closer
to island averages.
0
10
20
30
40
50
60
70
80
90
100
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
LUPAG = 82–89
SY = 30
Zoning = 11–18
N-P: Nonpotable
Executive Summary
Page ES-15
Hawaii County
Water Use and Development Plan Update
808 – Kilauea Aquifer Sector Area
The sustainable yield of this sector area is the second highest of all sector areas on the island.
Water demands associated with the full build-out to the maximum density of LUPAG and
County Zoning, and 20-year projections are sustainable with and without agricultural demands.
The WRPP indicates that a large quantity of high-level groundwater is developable; therefore,
these sources may continue to be the primary source of potable water. The key issue in this
sector area is whether to develop a municipal water system in the Central Puna area. Currently,
users rely on individual rainwater catchment systems, and the high volume of ambient rainfall
suggests that this is adequate. Undoubtedly, development of groundwater sources for such a
system is feasible; however, other factors, such as cost and public opinion, need to be
considered.
0
100
200
300
400
500
600
700
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
LUPAG = 36–127
SY = 618
Zoning = 5–95
N-P: Nonpotable
Executive Summary
Page ES-16
Hawaii County
Water Use and Development Plan Update
809 – Hualalai Aquifer Sector Area
This sector area includes Kona and the surrounding area, which has expanded significantly in the
last 20 years. Water demands in the sector area are the highest on the island due to the increases
in population and tourism. Development of high-level groundwater sources, primarily in the
Keauhou Aquifer System Area, has relieved some of the stress to the basal aquifer. However,
there should be concern with the on-going land development, as demands associated with the full
build-out to LUPAG maximum density exceed the sustainable yield by four to five times.
County Zoning full build-out demands are close to the sustainable yield if agricultural demands
are excluded, and exceed the sustainable yield if worst-case agricultural demands are included.
Although the 20-year projections indicate that demands will not approach the sustainable yield
for some time, measures should be considered to control future water demands. Demand-side
water conservation measures should be implemented by the potable water purveyors. It would
be prudent for County Planning officials to re-examine land use policies; controlling the
development density may be considered. Most importantly, the concept of using the highest
quality water for the highest end use should be followed. Efforts should be initiated to utilize
reclaimed wastewater and brackish basal groundwater for non-potable uses, thereby reserving
potable water for potable domestic use. Water transfer from the adjacent Southwest Mauna Loa
Aquifer Sector, which has a surplus of potable water sources, should also be explored.
0
50
100
150
200
250
300
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
SY = 56
LUPAG = 207–282
Zoning = 43–115
N-P: Nonpotable
Executive Summary
Page ES-17
Hawaii County
Water Use and Development Plan Update
ES.2.8 Summary of Conclusions and General Recommendations
The Hawaii Water Use and Development Plan Update promotes several common themes which
are applicable island-wide. The themes are as follows:
Reserve the highest quality of water for the most valuable end use
Promote water conservation
Initiate more monitoring and studies
Potable water is considered the highest quality water, and the sustenance of life is considered the
most valuable end use. Reclaimed wastewater, brackish groundwater, surface water and other
such lower quality water sources should be used for landscaping and agriculture, thereby
reserving potable water for human consumption.
Potable water usage above the County standard of 400 gpd per household is considered
excessive, and is therefore discouraged. End users, water purveyors and government agencies
should work together to conserve potable water.
The Department of Water Supply, as the largest purveyor of potable water on the island, plays a
key role in the use and protection of water resources. The goals and policies of DWS are
described in detail in Appendix C.
Additional studies and monitoring to determine the “safe” sustainable yields, on which the data
and analyses presented in the WUDP are base, are recommended. The next update of the Water
Resources Protection Plan should provide updated sustainable yields. Because of the
interdependencies between neighboring aquifer system and sector areas, regional studies should
be initiated. This is of special concern in West Hawaii. The WUDP proposes to create overall
resource management practices, and future updates should promote a policy of well-planned
source development.
CHAPTER 1 - INTRODUCTION
Page 1-1
Hawaii County
Water Use and Development Plan Update
Water: the lifeline of our islands. It is our most precious resource here in Hawaii. Water is the
driving force of our environment, our economy, and our Hawaiian Culture (Commission on
Water Resource Management website message).
1 INTRODUCTION
1.1 BACKGROUND
1.1.1 State Water Code
In 1987, the State Legislature passed the State Water Code (Hawaii Revised Statutes, Chapter
174C) to protect Hawaii’s surface and ground water resources. The State Water Code (the Code)
called for the establishment of a Commission on Water Resource Management (CWRM) that
would be responsible for administering the Code. Also, as part of the requirements set forth in
the Code, was the formulation of a Hawaii Water Plan that would serve as a dynamic, long-
range planning guide for the Commission. The Commission established the Hawaii
Administrative Rules Chapter 13-170, Hawaii Water Plan, which specifies and clarifies
definitions, procedures, requirements, etc., required by, but not specified in, the Code.
The Hawaii Water Plan consists of five parts: (1) the Water Resource Protection Plan, (2) the
Water Quality Plan, (3) the State Water Projects Plan, (4) the Agricultural Water Use and
Development Plan (AWUDP), and (5) the County Water Use and Development Plans (WUDP).
A separate WUDP is to be prepared by each of the four Counties. The AWUDP was added to
the Hawaii Water Plan by mandate under Act 101, Session Laws of Hawaii (SLH) 1998, by the
State Legislature.
The original Hawaii Water Plan was completed and adopted by the Commission in July 1990.
The Code calls for the Hawaii Water Plan, including all of its elements to be updated regularly
to reflect the current needs of the State. Each of the Counties is responsible to update their
respective WUDP as required. Updates of the various elements except the WQP and AWUDP
were drafted in1992, but were not officially adopted by the CWRM.
1.1.2 History of Hawaii County Water Use and Development Plan
In compliance with the State Water Code, the County of Hawaii Department of Water Supply
(DWS) was tasked with the responsibility to prepare the County of Hawaii Water Use and
Development Plan in 1988. The WUDP serves as a continuing long-range guide for the water
resource development in the County. Its objective is “to set forth the allocation of water to land
use through the development of policies and strategies which shall guide the County in its
planning, management, and development of water resources to meet projected demands.”
Section 13-170-31, Hawaii Administrative Rules states that the WUDP shall include but not be
limited to:
(1) Status of water and related land development including an inventory of existing water
uses for domestic, municipal, and industrial users, agriculture, aquaculture,
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
hydropower development, drainage, reuse, reclamation, recharge, and resulting
problems and constraints;
(2) Future land uses and related water needs; and
(3) Regional plans for water developments including recommended and alternative
plans, costs, adequacy of plans, and relationship to the water resource protection and
water quality plans.
The original County of Hawaii WUDP was adopted by the County Council by ordinance and
endorsed by Mayor Tanimoto on May 10, 1990. The WUDP was conditionally accepted by the
State Commission on Water Resource Management for incorporation into the Hawaii Water
Plan on June 27, 1990, with the provisions that the WUDP be reviewed and revised as necessary
by the County to coincide with the review process of the Hawaii Water Plan.
Adoption of the County of Hawaii WUDP was executed by County of Hawaii Ordinance No. 90-
60. The Ordinance requires that the County of Hawaii WUDP be updated every five years. The
first update was drafted in 1992, but was not officially adopted by the CWRM. In 2003, the
County of Hawaii Department of Water Supply produced the funding and initiated the update to
the WUDP.
1.1.3 Statewide Framework for the Update of the Hawaii Water Plan
The Statewide Framework for Updating the Hawaii Water Plan (Framework) dated February
2000 was created by the Commission on Water Resource Management to facilitate coordination,
integration, and consistency of the components of the Hawaii Water Plan. In addition, the
framework is a guide for preparation of the WUDP to insure effective implementation by the
County and utilization by the CWRM for resource management purposes.
The Framework requires data and analyses to be based on ground water and surface water
hydrologic units designated by the CWRM. However, the surface water hydrologic units were
only recently established and adopted in June 2005; and additional information on the surface
water hydrologic units is extremely limited. Therefore, the Hawaii WUDP update is based on
the ground water hydrologic units, and references the surface water hydrologic units as
applicable.
1.1.3.1 Ground Water Hydrologic Units
The State, as part of its Water Resource Protection Plan (WRPP), has established an aquifer
classification and coding system to describe and identify aquifers in the State of Hawaii. An
aquifer is generally described as a water bearing stratum of permeable rock, sand or gravel and
constitutes a source of ground water. Under the aquifer coding system, each island is the largest
component in the hierarchy, followed by Aquifer Sector Areas (ASEA), then Aquifer System
Areas (ASYA) located within the Aquifer Sector Areas.
An Aquifer Sector Area reflects an area with broad hydrogeological (subsurface) similarities
while maintaining traditional hydrographic (surface), topographic and historical boundaries
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
where possible. The Aquifer System Area is an area within an Aquifer Sector Area that is more
specifically defined by hydrogeologic continuity among aquifers in the System. This
classification scheme updates the island’s hydrographic areas initially established in 1959.
The aquifer code number begins with the U.S. Geological Service number for each island. The
island numbers are 1-Niihau, 2-Kauai, 3-Oahu, 4-Molokai, 5-Lanai, 6-Maui, 7-Kahoolawe, and
8-Hawaii. A two-digit Sector number and a two-digit System number follow the island number.
The Sector Areas and System Areas are also assigned geographic names. Figure 1-1 shows the
boundaries, codes and names of the Aquifer Sector Areas and System Areas on the island of
Hawaii. A description of each Aquifer System Area may be found in the Water Resource
Protection Plan component of the Hawaii Water Plan.
1.1.3.1.1 Sustainable Yield
Sustainable Yield (SY) is defined and described in the Water Resource Protection Plan (WRPP)
as follows:
Sustainable yield refers to the forced withdrawal rate of groundwater that could
be sustained indefinitely without affecting either the quality of the pumped water
or the volume rate of pumping. It depends upon the head selected as the minimum
allowable during continuous pumping. Head is the elevation [or height] of the
unconfined water table above sea level. There is not a unique value for
sustainable yield; the value depends on the head that will preserve the integrity of
the groundwater resource at the level decided upon by the manager.
Sustainable yield is equal to a fraction of the recharge. In a basal lens the
fraction is usually more than half and sometimes greater than three fourths where
initial heads are high. In high level aquifers about three fourths of the recharge
can be taken as sustainable yield.
[Groundwater recharge is the process of adding water to the aquifer through the
infiltration of precipitation on the land surface.]
The estimates of sustainable yield are not meant to be an exact number which
could be used in final planning documents. The estimates are constrained not only
by the scanty data base but also by the fact that they do not consider the
feasibility of developing the groundwater. The estimates should not be equated to
developable groundwater. In many regions, taking advantage of a high estimate
would not be economically feasible.
It should be noted that the Sustainable Yield value represents the sum of potable and non-potable
ground water. It is stressed that the SY estimates reflect the average daily pumpage over an
entire aquifer system area assuming wells are spaced optimally; and does not consider the
feasibility of developing the groundwater; nor whether the groundwater is potable or brackish.
Other hydrogeological studies have pointed to the uncertainty in the SY. The Water Resources
Protection Plan, like the Water Use and Development Plan, is a dynamic document, and the SY
estimates continue to be evaluated. Subsequent updates of the WRPP should provide updated
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
values of the SY. Therefore, caution should be exercised in comparing the Sustainable Yield to
projected water demands. As stated in the WRPP, estimates of the Sustainable Yield should be
used as a guide in planning rather than a definitive constraint.
Table 1-1 lists the geographical area of coverage and estimated sustainable yield in million
gallons per day (mgd) published in the Hawaii Water Resource Protection Plan for the 9 aquifer
sector areas on the island of Hawaii.
Table 1-1: Aquifer Sector Areas
Sector Area
Code
Sector Area
Area
(Acres)
Sustainable Yield
(MGD)
801 Kohala 154,118 154
802 E. Mauna Kea 385,952 388
803 W. Mauna Kea 180,570 24
804 N.E. Mauna Loa 256,640 740
805 S.E. Mauna Loa 447,859 291
806 S.W. Mauna Loa 406,893 130
807 N.W. Mauna Loa 186,246 30
808 Kilauea 361,338 618
809 Hualalai 200,282 56
Total for Island 2,579,898 2,431
1990 State Water Resource Protection Plan
1.1.3.2 Surface Water Hydrologic Units
The CWRM recently established surface water hydrologic units and a coding system, and
adopted the CWRM Surface-Water Hydrologic Units: A Management Tool for Instream Flow
Standards report in June 2005. Key objectives of the CWRM surface water hydrologic units
include the following:
1) Define and delineate unique units that can accommodate the relational
requirements in a database environment, while providing a system that can be
easily understood by the general public.
2) Develop an information management system which utilizes the coding system to
relate surface-water permits and other resource information to a given unit.
3) Define hydrologic units to be considered in the analysis and development of
instream flow standards.
4) Provide a reference system that promotes better information management of other
resource inventories.
5) Promote the sharing and collection of surface-water resource data between
government agencies, the public, private entities, and community organizations.
6) Improve the overall coordination of monitoring, data collection, and field
investigation efforts.
CapeKumukahi
Ka Lae
Honaunau
Kailua
Hilo
Kawaihae
Kiholo Bay
Ookala
Upolu Point
ANAEHOOMALU
WAIMEA
MAHUKONA
HAWI
WAIMANU
HONOKAA
PAAUILO
HAKALAU
ONOMEA
HILO
KEAAU
PAHOA
KALAPANA
HILINA
KEAIWA
OLAA
KAPAPALA
NAALEHU
KALAE
MANUKA
KAAPUNA
KEALAKEKUA
KIHOLO
KEAUHOU
Hawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLAN
Job No. 2003-818
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
27 MGD / 80101
110 MGD / 80102
31 MGD / 80201
17 MGD / 80103
24 MGD / 80301
60 MGD / 80202
150 MGD / 80203
147 MGD / 80204
347 MGD / 80401
393 MGD / 80402
435 MGD / 80801
157 MGD / 80802
9 MGD / 80803
17 MGD / 80804
117 MGD / 80503
19 MGD / 80502
124 MGD / 80501
31 MGD / 80504
42 MGD / 80601
50 MGD / 80602
38 MGD / 80603
30 MGD / 80701
18 MGD / 80902
38 MGD / 80901
KOHALA154 MGD / 801
E. MAUNA KEA388 MGD / 802
W. MAUNA KEA24 MGD / 803
N.W. MAUNA LOA30 MGD / 807
HUALALAI56 MGD / 809
N.E. MAUNA LOA740 MGD / 804
KILAUEA618 MGD / 808
S.E. MAUNA LOA291 MGD / 805
S.W. MAUNA LOA130 MGD / 806 KAU
PUNA
NORTH HILOSOUTH KOHALA
SOUTH KONA
NORTHKOHALA
0 10 20 305
Miles
FIGURE 1-1
JUDICIAL DISTRICTSANDAQUIFER BOUNDARIES
HAMAKUA
SOUTH HILONORTH KONA
HYDROLOGIC UNITSSustainable Yield / Aquifer CodeTOTAL = 2431 MGD
JUDICIAL DISTRICTSAQUIFER SECTOR AREASAQUIFER SYSTEM AREAS
LEGEND
Island of Hawaii
Chapter 1 - Introduction
Page 1-7
Hawaii County
Water Use and Development Plan Update
A hydrologic unit is defined by the Code as “a surface drainage area or a ground water basin or a
combination of the two.” The majority of surface water hydrologic units have boundaries which
closely match the drainage basins or watershed units. The CWRM defines a watershed unit in
accordance with the State Definition and Delineation of Watersheds report as follows:
A watershed unit is comprised of a drainage basin (or basins) which include both stream
and overland flow, whose runoff either enters the ocean along an identified segment of
coastline (coastal segment) or enters an internal, landlocked drainage basin. The
watershed units for an island are defined so that all segments of coastline are assigned to
a unique watershed unit and so that all areas of an island are assigned to one, and only
one, watershed unit.
Similar to the aquifer code system, the surface water hydrologic unit code number begins with
the U.S. Geological Service number for each island. The island numbers are 1-Niihau, 2-Kauai,
3-Oahu, 4-Molokai, 5-Lanai, 6-Maui, 7-Kahoolawe, and 8-Hawaii. A three-digit System number
follows the island number. The Systems are also assigned geographic names. Figure 1-2 shows
the boundaries of the 166 surface water hydrologic units and the 9 aquifer sector areas for
comparison on the island of Hawaii. Information on each surface water hydrologic unit is
extremely limited since the coding system is the first-step towards improving the organization
and management of surface water information that CWRM collects and maintains.
1.1.4 The Hawaii Water Plan Update Status
As required by the Code, the Hawaii Water Plan, including all of its elements, must be updated
regularly to reflect the current needs of the State. Currently, the update status of the various
elements is as follows:
PLAN ELEMENT STATUS
Water Resource Protection Plan Second update in progress
Water Quality Plan 1990 – first update completed
State Water Projects Plan 2003 – Second update completed
Agricultural WUDP Plan in development:
Phase 1 – 2003
Phase 2 – 2004
Phase 3 – In progress
Hawaii County WUDP 2006 – Second update projected completion
Honolulu, Maui & Kauai WUDPs Second update in progress
Act 101, SLH 1998 requires that the AWUDP should provide a master inventory of irrigation
systems, identify the extent of repair and rehabilitation that would be required over a 5-year
period, and provide a long-range management plan. The Framework further expands the scope
to provide for the development of agricultural water demand projections, which is essential for
the WUDP updates. The AWUDP, dated December 2003, and revised in December 2004, was
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Hawaii County
Water Use and Development Plan Update
prepared to meet the mandate of Act 101, and to review and discuss the potential for
transitioning from monocrop corporate farming into diversified crop farming, along with the
potential opportunities available in the new diversified farming. However, due to funding and
time constraints, a comprehensive plan has not yet been completed.
1.2 PHYSICAL SETTING
1.2.1 Location and Size
The County of Hawaii encompasses the island of Hawaii, the largest most southeastern island of
the Hawaiian archipelago. The total area of the island is approximately 4,028 square miles. The
island is divided into 9 judicial districts, and has 9 aquifer sector areas and 166 surface water
hydrologic units, as previously shown on Figures 1-1 and 1-2. The 2000 U.S. Census reports
the island’s resident population to be 148,677 residents.
1.2.2 Climate
The size of the island and range of land elevations contribute to a climate of great diversity. The
island lies in the path of the northeast trade winds and has an orographic rainfall pattern or a
rainfall pattern caused by the mountains, typical of the larger islands in the Hawaiian chain.
Rainfall reaches a maximum intensity in areas from 2,000 to 3,000 feet elevation and then
diminishes, so that the upper slopes are semi-arid. In northeast Hawaii, the moisture laden trades
cool as they rise up the mountain slopes and lose much of their moisture as rain. The prevalence
of trades throughout most of the year accounts for the island’s high average annual rainfall of 72
inches. Over 300 inches fall annually on parts of the windward or northeast slopes of the island.
As the winds descend along the leeward (southwest) slopes, the air becomes dryer and warmer.
Rainfall declines accordingly, resulting in a near arid climate along the leeward coastline. The
mean annual rainfall in most leeward areas is approximately 10 inches. Along the Kona coast,
however, the difference between land and water temperatures on warm days, particularly in the
summer, generates a moderate sea breeze circulation. This results in frequent and heavy
showers, which produce a much higher mean rainfall than in other leeward areas. Generally, in
areas where trade winds predominate, the dry months are from May through September. The
wet months occur from October through April. In the Kona region, sheltered from the trades,
summer rainfall predominates.
Under prevailing trade wind conditions, from 50 to 70 percent of the time, temperature inversion
greatly influences moisture distribution in the air surrounding the island. Moisture is high and
well distributed below the inversion level, which varies between 5,000 and 7,000 feet elevation;
air above the inversion is relatively dry. Relative humidity below the inversion is roughly 70 to
80 percent in windward areas, and 60 to 70 percent in the dryer leeward areas. Above the
inversion, relative humidity is generally less than 40 percent, often declining to 10 or even 5
percent.
804 - N.E. MAUNA LOA
805 - NAALEHU
806 - S.W. MAUNA LOA
807 - N.W. MAUNA LOA
809 - HUALALAI
803 - W. MAUNA KEA
801 - KOHALA
802 - E. MAUNA KEA
LEGEND:
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
Surface WaterHydrologic Units
INDEX MAP - Island of Hawaii
0 4 8 122
Miles
Surface WaterHydrologic UnitsBoundaryHawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-818FIGURE 1-2
808 - KILAUEA
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Hawaii County
Water Use and Development Plan Update
Because of the consistently mild temperatures of the ocean waters surrounding the islands,
temperatures in the air moving across the ocean and over the island are also mild and do not vary
significantly. The warmest month is August and the coldest is February. Temperatures above
90oF are very unusual, except in the dry leeward area of South Kohala, where maximum
temperatures in the low 90’s are common. A temperature less than 55 oF is uncommon, except at
elevations above 2,500 feet. The summits of Mauna Kea and Mauna Loa frequently have snow
in the winter.
Northeasterly trade winds prevail much of the time on the island of Hawaii, as elsewhere in the
state. Although these winds approach the island at a fairly constant speed, the uniform flow is
distorted as the trade winds traverse the island. These winds combine with local winds on the
mountain slopes and lowlands to form complex patterns. During the cooler winter months,
southerly winds generally replace the trades. Occasional tropical storms also generate winds
from various directions. Over the ocean surrounding the island, average wind speeds are highest
during the summer trade wind period, exceeding 12 miles per hour 50 percent of the time.
During the winter months wind speeds exceed 12 miles per hour about 40 percent of the time.
The Island of Hawaii recently experienced continuous drought conditions, lasting from 1998
through 2003, during which the County declared frequent drought emergencies. The County
sustained water shortages and heavy damage to agriculture and the cattle industries.
1.2.3 Geology
The Hawaiian Islands are part of a chain of islands that extend southeast from the Aleutian
Islands. Most of the islands northwest of the Hawaiian Archipelago have disappeared or only
small portions of land or tips of the islands rise above the sea. These islands are called the
Leeward Islands, or the Northwestern Hawaiian Islands, and include Midway Island, Kure Atoll
and French Frigate Shoals. The Hawaiian Islands are the newest land mass of this chain of
islands.
The island of Hawaii is the largest of the eight major islands of the Hawaiian Archipelago, with a
total area that exceeds the rest of the other island areas combined. The island is the youngest
from a geological viewpoint. Rocks from its earliest volcano indicate an age of about 700,000
years. In contrast, Kauai is over 5 million years old, and Oahu is over 2 million years old.
Five shield volcanoes formed the island of Hawaii: Kohala, Mauna Kea, Mauna Loa, Hualalai,
and Kilauea. Figure 1-3 shows the volcano locations. Kohala is considered extinct; Mauna Kea
has not erupted for 4,500 years and is dormant; and Hualalai last erupted in 1801 and is
considered dormant. Mauna Loa and Kilauea are active volcanoes. A sixth volcano, the Loihi
Seamount, is active and forming on the seafloor south of Kilauea.
Each volcanic dome consists primarily of permeable thin-bedded basaltic lava flows. A veneer
of andesitic lavas covers much of Mauna Kea; and one of andesite and trachyte covers part of the
Kohala Mountain, attesting to the older age of the Kohala volcanic series. The andesitic and
trachytic flows are mostly thick-bedded and are poorly permeable.
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
Numerous dikes have intruded lava flows in the rift zones. However, exposed dikes are found
only in deeply eroded valleys in the eastern slope of Kohala Mountain. They form almost
impermeable vertical barriers, which cut across lava flows and often times impound large
quantities of ground water. Volcanic-ash deposits, several feet thick in places, crop out in about
450 square miles of the northern, northeastern, and southeastern parts of the island. Most of the
ash deposits were buried by later lava flows. The buried ash deposits, intercalated in permeable
lava flows, act as perching members for important high-altitude perched-water bodies in many of
the northeastern and southeastern parts of the island. Because of the highly pervious nature of
many of the surface rocks, the island has only a limited number of perennial streams. These
streams are found on the eastern (or windward) slopes of Mauna Kea and Kohala Mountain. A
few streams flow perennially in their wet upper reaches but lose their water flowing over the
permeable ground well before reaching the coast. However, these streams are subject to flash
floods during heavy rains.
There is little evidence of extensive coastal-plain sedimentation and of deep erosion, except in
the northeastern slopes of the Kohala and Mauna Kea mountains. As a result, sedimentary
materials are sparse and scattered. They include alluvium, talus, dune and beach deposits, and
glacial deposits on Mauna Kea. Due to the sparse distribution, sedimentary material has little
impact on hydrology.
Figure 1-4 shows a geologic map of Hawaii Island. Accompanying the geologic map is Table
1-2 showing the stratigraphic sequence of the volcanic rock units on Hawaii Island.
Chapter 1 - Introduction Page 1-15 Hawaii County Water Use and Development Plan Update Table 1-2:Stratigraphic Rock Units in the Island of Hawaii (The volcanic rocks of Mauna Loa, Mauna Kea, and Hualalai, those of Mauna Kea and Kohala, and those of Mauna Loa and Kilauea interfinger) Age Hualalai Kohala Mountain Mauna Loa Kilauea Mauna Kea Historic Historic member of Hualalai volcanic series (volcanics of 1801) Historic member of Kau volcanic series (volcanics of 1832-1942) Mud flow of 1868 Historic rocks of Puna volcanic series (volcanics of 1790-1934) Dunes Dunes Recent Unconsolidated alluvium, dunes and landslides Upper member of Laupahoehoe volcanic series Ribbons of gravel and small alluvial fans Glacial debris and fluvial conglomerates Exposed part of prehistoric member of the Hualalai volcanic series Fluvial conglomerates Prehistoric member of Kau volcanic series Prehistoric member of Puna volcanic series Lower member of Laupahoehoe volcanic series Late Pleistocene Pahala ash (exposed on Waawaa volcanics only) Pahala ash (not differentiated) Pahala ash Pahala ash Pahala ash Fluvial conglomerates Early and Middle Pleistocene Hawi volcanic series Kahuku volcanic series Pliocene Waawaa volcanics and lower unexposed part of Hualalai volcanic series Pololu volcanic series Ninole volcanic series Hilina volcanic series Hamakua volcanic series Source: GEOLOGY AND GROUND-WATER RESOURCES OF THE ISLAND OF HAWAII, H.T. Sterarns & G.A. MacDonald, Hawaii Division of Hydrography, 1946, p. 62`1Great erosional unconformity
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
1.2.4 Hydrology
The hydrologic cycle or water cycle is the cyclical movement of water between the air, land and
sea, as illustrated in Figure 1-5. Generally, it begins with evaporation of water from the ocean
and returns to the ground as precipitation. Some of the precipitation or rainfall may be lost
through evapo-transpiration; it may become surface runoff or runoff into streams and empty into
the ocean; or it may infiltrate the ground to become soil moisture or collect as ground water and
eventually escape to the sea. Water supply in the islands is dependent upon this cycle.
Figure 1-5: The Water Cycle
The island of Hawaii, which lies in the path of the prevailing northeast trade winds, has an
orographic rainfall pattern. The heaviest rainfall occurs on the eastern or windward side of the
island. The leeward or western slopes receive little of the orographic trade wind rainfall. Rain in
the leeward side is generally the result of convective-type showers. The island rainfall averages
72 inches per year, equivalent to 13.82 billion gallons of water per day. As indicated by the
isohyetal lines of the rainfall map shown in Figure 1-6, rainfall gradients are very steep. The dry
leeward side at Kawaihae averages less than 7 inches of rain per year, while the Hilo Forest
Reserve averages 300 inches per year. Rainfall can drastically fluctuate from year to year, and
has often exceeded 300 percent fluctuation. The intensity of rainfall is also very high with 12
0 1020305
Miles
60"
20"
240"
10"
160"
120"
40"
200"160"80"
120"
60"
80"
60"
40"
40"
120"
80"
60"
20"
80"
60"
20"
40"
80"
20"
20"
Hawaii County
Department of Water Supply
DWS UPDATE TO THE WATER USE
AND DEVELOPMENT PLAN
Job No. 2003-818
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers
1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
FIGURE 1-6
ANNUAL RAINFALL
Island of Hawaii
Source: (GIS Layer) Office of Planning, State of Hawaii, February 2004
Addendum No. 1, 2/3/2012
Chapter 1 - Introduction
Page 1-19
Hawaii County
Water Use and Development Plan Update
inches or more of rain a day occurring at least once a year, and instances of over 30 inches of
rain occurring within a 24-hour period.
The steep and permeable slopes generally result in ephemeral or flashy streams. This can be
attributed to the abundant rainfall that is fairly well distributed throughout the year to yield more
water than the infiltration capacity of the permeable surfaces. Perennial streams are scarce
except on the windward slopes of the Kohala Mountain and Mauna Kea between Hilo and
Maulua River near Laupahoehoe.
Ground water is less susceptible to droughts and seasonal changes than surface water, and
therefore is a more dependable water source. There are four different types of ground water on
the island: 1) basal water floating on salt water; 2) dike confined water; 3) water perched on
relatively impervious soil or rock formation; and 4) shallow ground water. The greatest ground
water reservoir is the basal water table near sea level, which is a fresh water lens that “floats” on
sea water. This phenomenon is known as the Ghyben-Herzberg principle. Due to the difference
in specific gravity of sea water and fresh water, theoretically for every foot of fresh water above
sea level 40 feet of fresh water extend below sea level to maintain the equilibrium. However, in
actuality, there is a zone of mixture or transition zone from sea water to fresh water.
The generalized maps in Figures 1-7 and 1-8 show ground water areas on the island, and
locations where ground water recovery by wells and tunnels is feasible. The maps, prepared by
the U.S. Geological Survey in 1946, are still applicable today with a few modifications. One
such modification is the high-level ground water encountered in the early 1990’s within the
Keauhou Aquifer System Area, which is within the Hualalai Aquifer Sector Area 809.
Exploratory drilling at elevations above 1600 feet mean sea level (msl) encountered water
elevations ranging from 25+ feet msl to 460+ feet msl. A Study of the Ground-Water Conditions
in North and South Kona and South Kohala Districts, Island of Hawaii, 1991-2002 published by
CWRM in September 2003, was the culmination of efforts to collect and analyze ground water
data from West Hawaii. The report recommends “that this monitoring work continue, and that
new hydrological and geological information be analyzed and incorporated into current
understanding of West Hawaii.”
1.3 ECONOMY AND POPULATION
1.3.1 Economy
The economy of the County of Hawaii is supported by agriculture, tourism, the manufacturing of
export products, and research and development. Support of research and development in
emerging fields such as astronomy, high technology, renewable energy, health and wellness,
agricultural and eco-tourism, diversified agriculture and aquaculture is an important economic
force.
Tourism replaced the sugar industry as the primary economic generator in the mid-1980’s, with
the last sugar harvest on the island in 1997. Tourism related facilities and activities are primarily
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
on the west side of the island, with continued development concentrated in the Kohala and Kona
Districts.
Agriculture continues to be a major economic generator, and includes raising cattle and other
livestock, farming of coffee, macadamia nuts, papaya, flowers and nursery products, vegetables,
aquaculture, forestry and several processing plants that utilize locally grown products. Livestock
production has been declining steadily since the late 1980’s primarily due to the high cost of
importing feed which resulted in the closing of many feedlots within the State. The market for
locally grown products with the growth of local demand and potential of increasing exports
indicates promising opportunities for expansion of agriculture. Forestry is a promising industry
with the excellent growing climate and the availability of former sugarcane lands, pasture and
brush lands. Forest products such as eucalyptus and higher value hardwoods such as toon,
maple, and koa are already being produced commercially on the island.
Aquaculture is also a promising industry. According to the County General Plan, “aquaculture
operations County-wide have grown from eight operations in 1982 to forty-three in 1996.
During this same period, annual revenues have grown from $90,600 to $13,200,000. The County
accounts for 37 per cent of the total aquaculture operations within the State but accounts for over
80 per cent of the total production and over 84 per cent of the production value.” The Natural
Energy Laboratory of Hawaii Authority (NELHA) was first created in 1974 by the Hawaii State
Legislature on 322 acres of land in Keahole, North Kona, and continues to be a State subsidized
facility now encompassing 870 acres of land. The Pacific Aquaculture and Coastal Resource
Center is now being developed on two sites in Hilo, and is funded by the County of Hawaii, State
of Hawaii, the U.S. Economic Development Administration, and the University of Hawaii.
1.3.2 Population
The County population has increased at a rate of 23 percent between 1990 and 2000, as
compared to 9 percent for the State. According to the County General Plan, “the district of Puna
saw the largest increase at 51 per cent, followed by South Kohala (44 per cent), North Kohala
(41 per cent), Kau (31 per cent), North Kona (28 per cent), South Kona (12 percent), North Hilo
(12 per cent), Hamakua (10 per cent) and South Hilo (6 per cent).” The County General Plan
projects that Puna will continue its strong population growth, while growth in North and South
Kohala and North and South Kona will be closely associated with the growth of the visitor and
agricultural industries in the districts.
The County General Plan has three population projections for the island to the year 2020, as
listed in Table 1-3. Series A is a conservative projection, Series B is a medium projection, and
Series C projects more rapid growth. More detailed projections for each judicial district are
presented in the General Plan.
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
Table 1-3: County General Plan Population Projection
GROWTH
RATE 2000 2005 2010 2015 2020
A – Low 148,677 159,397 175,388 193,118 213,452
B – Medium 148,677 159,907 176,938 195,965 217,718
C - High 148,677 166,576 188,031 211,357 237,323
1.4 LAND USE
1.4.1 State Land Use
The State Land Use classification is very general with only four land use districts: Urban, Rural,
Agriculture and Conservation. The County administers the local land use policy within the
Urban, Rural and Agricultural districts, while the State of Hawaii Board of Land and Natural
Resources regulates activities within the Conservation district. The County of Hawaii State Land
Use acreage by classification is listed in Table 1-4 and shown in Figure 1-9.
Table 1-4: State Land Use Classification
State Land Use Acreage % of Total
Urban 54,267 2
Rural 807 <1
Agricultural 1,184,599 46
Conservation 1,338,135 52
Total 2,577,808 100
General Plan, February 2005 (Data as of May 2000)
State of Hawaii, DBEDT, Office of Planning GIS Data
County of Hawaii Planning Department
1.4.2 County General Plan
The County of Hawaii General Plan is the policy document for long-range development, which
establishes a balanced land use pattern to guide development based on long-term goals. The
General Plan underwent a revision program beginning in 2001; and this program was finalized
and adopted in February 2005. The General Plan goals and policies as applicable to the WUDP
are listed in Appendix A.
The General Plan Land Use Pattern Allocation Guide (LUPAG) Map, indicates the general
distribution of various land uses on the island. The land use pattern is a broad, flexible design
intended to guide the direction and quality of future developments in a coordinated and rational
manner. The land use designations and their associated acreage for the island are listed in Table
1-5:
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Hawaii County
Water Use and Development Plan Update
Table 1-5: General Plan Land Use Pattern Allocation Guide
LUPAG Acreage* % of Total
High Density Urban 1305 <<1
Medium Density Urban 5,947 <1
Low Density Urban 37,253 1
Industrial 10,977 <1
Important Agricultural Land 386,283 15
Extensive Agriculture 661,382 26
Orchard 1,603 <<1
Rural 47,996 2
Resort/Resort Node 5,676 <1
Open Area 35,696 1
Conservation Area 1,355,021 52
Urban Expansion Area 29,142 1
University Use 1,125 <<1
Total 2,584,274 100
*Planning Department Estimates – GIS Data
The General Plan water utility policies are as follows:
(a) Water system improvements shall correlate with the County's desired land use
development pattern.
(b) All water systems shall be designed and built to Department of Water Supply standards.
(c) Improve and replace inadequate systems.
(d) Water sources shall be adequately protected to prevent depletion and contamination from
natural and man-made occurrences or events.
(e) Water system improvements should be first installed in areas that have established needs
and characteristics, such as occupied dwellings, agricultural operations and other uses,
or in areas adjacent to them if there is need for urban expansion.
(f) A coordinated effort by County, State and private interests shall be developed to identify
sources of additional water supply and be implemented to ensure the development of
sufficient quantities of water for existing and future needs of high growth areas and
agricultural production.
(g) The fire prevention systems shall be coordinated with water distribution systems in order
to ensure water supplies for fire protection purposes.
(h) Develop and adopt standards for individual water catchment units.
(i) Cooperate with the State Department of Health to develop standards and/or guidelines
for the construction and use of rainwater catchment systems to minimize the intrusion of
any chemical and microbiological contaminants.
(j) Cooperate with appropriate State and Federal agencies and the private sector to
develop, improve and expand agricultural water systems in appropriate areas on the
island.
(k) Promote the use of ground water sources to meet State Department of Health water
quality standards.
State Land UseDistrict Boundaries(2004)
P A C I F I C O C E A N
0 4 8 122
Miles
Hawaiian Home Lands
Agricultural
Conservation
Rural
Urban
Aquifer System Boundaries
State Land Use District Boundaries
Cape Kumukahi
Ka Lae
Honaunau
Keauhou
Hilo
Waikoloa
Kailua-Kona
Hamakua
Honomu
Hawi
80701Anaehoomalu
80301Waimea
80103Mahukona
80101Hawi
80102Waimanu
80201Honokaa
80202Paauilo
80203Hakalau
80204Onomea
80401Hilo
80402Keaau
80801Pahoa
80802Kalapana
80803Hilina
80804Keaiwa
80501Olaa
80502Kapapala
80503Naalehu
80504Ka Lae
80601Manuka
80602Kaapuna
80603Kealakekua
80902Kiholo
80901Keauhou
LEGEND:
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers
1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
INDEX MAP - Island of HawaiiHawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-818FIGURE 1-9
Chapter 1 - Introduction
Page 1-27
Hawaii County
Water Use and Development Plan Update
(l) Continue to participate in the United States Geological Survey's exploratory well drilling
program.
(m) Seek State and Federal funds to assist in financing projects to bring the County into
compliance with the Safe Drinking Water Act.
(n) Develop and adopt a water master plan that will consider water yield, present and future
demand, alternative sources of water, guidelines and policies for the issuing of water
commitments.
(o) Expand programs to provide for agricultural irrigation water.
1.4.3 County Zoning
The Zoning Code is the County’s legal instrument that regulates land development, and
implements the General Plan policies; therefore, zoning must be consistent with the General
Plan. The zoning districts with associated acreage for the island are listed in Table 1-6:
Table 1-6: County Zoning
County Zoning Districts Acreage * % of Total
Single-family residential 18,240 <1
Multi-family residential 3,318 <1
Resort 1,213 <1
Commercial 1,994 <1
Industrial 5,684 <1
Industrial-Commercial Mixed 269 <<1
Family Agriculture 332 <<1
Residential Agriculture 3,139 <1
Agriculture 1,243,350 48
Open 345,920 13
Project District 1,744 <1
Agricultural Project District 23 <<1
Lands not zoned
(includes Forest Reserves and
National Parks) 939,941 37
Total 2,565,167 100
* Estimate – GIS Data, 2004 Zoning
County Zoning is more detailed than the General Plan, with zoning codes designated for virtually
every parcel. The Residential, Resort, Commercial, and Industrial designations specify the
required minimum building site area allowed for each unit.
1.4.4 Community Development Plans
The Community Development Plan (CDP) program was mandated by the 2005 General Plan to
translate broad goals, objectives, and policies into implementation actions as they apply to
specific geographical areas. The CDP are “intended to be a forum for community input into
managing growth and coordinating the delivery of government services to the community.” The
Chapter 1 - Introduction
Page 1-28
Hawaii County
Water Use and Development Plan Update
General Plan states that a CDP is not mandatory for every region on the island; however, the
need for a CDP “for a particular area should be assessed considering a number of factors,
including how much is public infrastructure challenged by recent or anticipated growth and
whether there are significant efforts to change the zoning and land use in the area.” Once
finalized the CDP would be enacted by the County Council by ordinance.
CDP for North and South Kona, Puna, and North and South Kohala Districts have been initiated.
North and South Kona CDP kick-off public information meetings started in September 2005,
Puna meetings began in February 2006, North Kohala meetings began in November 2006, and
South Kohala meetings began in September 2006. Planning efforts are in progress; final CDP
should be considered in future WUDP updates.
1.5 EXISTING WATER RESOURCES
1.5.1 General
Water resources that are utilized currently on the island of Hawaii include ground water, surface
water or stream diversions, rainwater catchment and reclaimed wastewater. Water quality varies
with the source, and depending on the proposed use, treatment requirements also vary. Water
quality protection is covered by the State’s Water Quality Plan, which describes the Department
of Health and other programs which protect existing and potential sources of drinking water.
Current available information on water resources is limited, and records on individual rainwater
catchment systems and stream diversions is extremely limited.
1.5.2 Ground Water
Ground water is the primary source of supply for the majority of water users on the island, for
both county-owned and private water systems. Figure 1-7, shown previously, depicts ground
water resource areas on the island. Figure 1-8 shows areas where ground water recovery by
wells is feasible. As can be seen from Figure 1-7, although there appears to be an abundant
supply of basal water underlying the island, the high ground elevations and resulting depth to
ground water sources makes it very expensive to recover the basal water in many parts of the
island.
1.5.2.1 Wells
“Well” is defined by the Water Code as, “an artificial excavation or opening into the ground, or
an artificial enlargement of a natural opening by which ground water is drawn or is or may be
used or can be made usable to supply reasonable and beneficial uses within the State.” The
inventory of the wells or existing ground water sources was obtained from the CWRM database,
which was developed with information received from the Well Registration program; and since
1988, has been supplemented with information obtained through the well construction/pump
installation permitting process. The database is the best available information and was used to
evaluate the existing ground water resources; however, it is not complete and lacks information
pertinent to the WUDP for many of the wells, such as installed pump capacity and chloride
concentration. The installed pump capacity is critical because it indicates the quantity of water
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
Figure 1-10: Registered Wells
MAP CURRENTLY NOT AVAILABLE ON-LINE
Chapter 1 - Introduction
Page 1-31
Hawaii County
Water Use and Development Plan Update
that may be pumped from each well. The chloride concentration is important because the
potability of the water, i.e. potable, brackish or saltwater is not always evident and has varying
impacts on the aquifer sustainable yield. The Water Code and Administrative Rules do not
require well owners in non-designated water management areas to notify the CWRM of changes
in ownership and type of use; however, the CWRM updates its records whenever it becomes
aware of such changes. In July 2005, the CWRM began issuing certificates of well construction
and pump installation completion that require landowners to notify the CWRM if the well
operator or landowner changes.
Based on the CWRM well database and limited additional update information, the island of
Hawaii has 355 well sources, which are shown on Figure 1-10. The pumping capacity of the
well sources reporting pumpage to the CWRM is 274.2 MGD, as listed in Table 1-7.
Table 1-7: Summary of Installed Pumps in Existing Well Sources
Category # of Wells
Capacity*
(MGD)
% of Total
Capacity
Municipal 97 91.6 33.4
Domestic 30 3.1 1.1
Irrigation 129 45.0 16.4
Industrial 39 102.2 37.3
Others 60 32.3 11.8
Total 355 274.2 100.0
* Capacity based on available installed pump capacity data; many well pump capacities are not listed in the database.
1.5.3 Surface Water
The Hawaii Stream Assessment (HSA) lists 376 perennial streams throughout the State. Of the
376 streams, 132 perennial streams are on the island of Hawaii as shown on Figure 1-11. The
majority of the streams are in the windward areas of higher rainfall, and practically all are on the
slopes of Kohala Mountain and Mauna Kea. In other areas, streams are intermittent or non-
existent. The HSA notes that the over 100 streams located on the Kohala-Hamakua coast are
difficult to access and very little information is available; therefore, the level of confidence of the
attributes for most of these streams is low.
Table 1-8 is from the HSA, and lists the available gaging records for the island.
In accordance with the Code, the CWRM must establish and administer instream flow standards
on a stream-by-stream basis as necessary to protect public interests. Instream flow standard is
defined as, “a quantity or flow of water or depth of water which is required to be present at a
specific location in a stream system at certain specified times of the year to protect fishery,
wildlife, recreational, aesthetic, scenic, and other beneficial instream uses.” According to
Section 13-169-46, Hawaii Administrative Rules, “Interim Instream Flow Standard for all
streams on Hawaii, as adopted by the commission on water resource management on June 15,
1988, shall be that amount of water flowing in each stream on the effective date of this standard,
Chapter 1 - Introduction Page 1-32 Hawaii County Water Use and Development Plan Update Table 1-8: Gaging Records CODE Gage is associated with stream with this HSA code QUAL USGS assessment of quality of records DATA NAME USGS Station Name DRAIN Drainage area above gage (sq. mi.) GAGE # USGS number of gage station. If all zeros, median and average are calculated flows. ACTIVE A – Active in January, 1991 DIV Diversions per USGS Y Diversion is present above gage N No diversion is present above gage D Gage is on a ditch MEDIAN Flow at gaging station exceeded 50% of time in cubic feet/second (cfs) AVERAGE Average of yearly mean flow in cubic feet/second (cfs) at gaging station YRS REC Years of record, 19..-19.. TYPE Type of data collected DATA C Continuous record E Extreme flows only, low and/or peak C-E Converted from continuous to extreme L Low flow P Peak flow new New gage 1988 – continuous record Note: cfs x 0.646 = MGD
Chapter 1 - Introduction Page 1-33 Hawaii County Water Use and Development Plan Update CODE NAME GAGE # ACTIVE MEDIAN AVERAGE YRS REC QUAL DATA DRAIN DIV TYPE DATA 8-1-07 Hapahapai Gulch at Kapaau 752600 A 62- N P 8-1-16 East branch Honokane nui Str nr Niulii 747500 21.0 63-69 Y C 8-1-17 East Honokaa iki intake to Awini Ditch nr Niulii 744000 0.9 1.76 27-72 C 8-1-29 Kukui Str nr Waimanu 742000 0.9 39-66 N C 8-1-30 Paopao Str nr Waimanu 741000 1.1 3.33 39-52 N C 8-1-31 Waiaalala Str nr Waimanu 740000 0.6 1.10 39-52 N C 8-1-32 Punalulu Str nr Waimanu 739000 2.4 6.53 39-52 N C 8-1-33 Kaimu Str nr Waimanu 738000 3.2 8.68 39-52 N C 8-1-35 Waiilikahi Str nr Waimanu 737000 4.3 10.00 39-60 N C 8-1-44 Kawainui Str nr Kamuela 720000 A 4.3 14.80 64- G 1.58 N C 8-1-44 Alakahi Str nr Kamuela 725000 A 3.1 6.88 64- G 0.87 Y C 8-1-44 Wailoa Str nr Waipio 732200 51.0 75 01-69 Y C 8-1-44 Kawaiki Str nr Kamuela 720300 A 1.7 4.27 68- G 1.45 N C 8-1-55 Honokaia Gulch tributary nr Honokaa 717950 A 62- N P 8-1-60 Ahualoa Gulch at Honokaa 717920 A 62- N P 8-1-87 Keehia Gulch nr Ookala 717850 A 62- N P 8-2-06 Manowaiopae Str nr Laupahoehoe 717820 3.4 8.42 65-71 G 1.04 Y C 8-2-16 Pahokupuka Str nr Papaaloa 717800 A 7.7 27.10 62- G 2.76 N C-P 8-2-37 Kapehu Str nr Pepeekeo 717650 A 62- N P 8-2-37 Kapehu Str at Piihonua nr Hilo 709000 50.90 28-37 4.84 N 8-2-39 Alia Str nr Hilo 717600 A 12.0 62- N C-P 8-2-47 Kalaoa Mauka Str nr Hilo 717400 A 62- N new 8-2-56 Honolii Str nr Hilo 716000 13.0 52.00 24-32 N C 8-2-56 Honolii Str nr Papaikou 717000 A 38.0 125.00 11- F 11.60 N C 8-2-60 Wailuku R nr Pua Akala 701700 64-65 N C 8-2-60 Wailuku R at Hilo 713000 A 160.0 386.00 77- G 256.00 Y C 8-2-60 Wailuku R nr Humuula 701750 2.82 65- G 34.80 N C 8-2-60 Wailuku R nr Kaumana 701800 2.9 27.60 66- G 43.40 N C 8-2-60 Wailuku R at Pukamaui nr Hilo 703000 26.7 93.30 23-40 Y C
Chapter 1 - Introduction Page 1-34 Hawaii County Water Use and Development Plan Update CODE NAME GAGE # ACTIVE MEDIAN AVERAGE YRS REC QUAL DATA DRAIN DIV TYPE DATA 8-2-60 Wailuku R nr Piihonua 704000 A 83.8 279.00 28- F 230.00 Y C 8-2-61 Waiakea Str nr Mountain View 700000 A 8.9 11.60 30- G 17.40 N C 8-2-61 Wailoa R at Hilo 701300 A 67- Y P 8-2-61 Wailoa R nr Hilo 701200 57-67 Y C 8-3-01 Hilea Gulch tributary nr Honuapo 764000 A 1.2 7.47 66- F 9.17 N C 8-3-01 Hilea Gulch tributary no. 2 nr Honuapo 765000 3.00 66- G 1.86 N C 8-4-01 Kiilae Str nr Honaunau 759800 0.21 58- G 0.67 N C 8-4-02 Right branch Waiaha Str nr Holualoa 759200 0.31 60- G 1.89 N C 8-4-02 Waiaha Str nr Holualoa 759500 57-68 Y C 8-4-02 Waiaha Str at Luawai nr Holualoa 759300 A 60- Y C-P 8-5-03 Waikoloa Str nr Kamuela 757000 4.0 7.21 47-71 G 0.78 N C 8-5-03 Waikoloa at marine dam nr Kamuela 758000 A 4.2 9.00 47- G 1.18 Y C 8-5-03 Kohakohau Str nr Kamuela 756000 A 1.9 8.49 56- G 2.51 Y C 8-5-03 Hauani Gulch nr Kamuela 759000 A 1.61 56- G 0.47 Y C
Chapter 1 - Introduction Page 1-35 Hawaii County Water Use and Development Plan Update Figure 1-11: Surface Water Resources MAP CURRENTLY NOT AVAILABLE ON-LINE
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
and as that flow may naturally vary throughout the year and from year to year without further
amounts of water being diverted offstream through new or expanded diversions, and under the
stream conditions existing on the effective date of the standard, except as may be modified [by
the commission].”
1.5.4 Rainwater Catchment
Rainwater catchment is the collection of rainwater from a roof or other surface before it reaches
the ground. Rainwater is typically a pure and free source of water, and is dependent upon
climate. As stated earlier, the island of Hawaii experienced drought conditions from 1998
through 2003. According to the Kau and South Kona Water Master Plan, rainfall in the Kau and
South Kona region has decreased since 1983 when Kilauea Volcano began erupting.
Accordingly, rainfall catchment systems were impacted significantly, and continue to be
impacted by the decrease in rainfall. The volcanic activity also impacts rainwater quality in the
vicinity of Kilauea, particularly due to the emission of sulfur dioxide which can combine with
water forming sulfuric acid. Acid rain has resulted in pH levels of water in catchment tanks as
low as pH 4 in the Kau and South Kona areas. The pH of pure water is pH 7.
1.5.5 Reclaimed Wastewater
Reclaimed wastewater potentially is a valuable resource, especially for irrigation purposes.
Based on information from the Department of Health, Wastewater Branch, Table 1-9 lists
existing reclaimed water applications, classifications and capacities throughout the island.
Table 1-9: Reclaimed Wastewater Resources
Wastewater
Reclamation Facility
(WWRF)
Reclaimed
Water
Classification
WWRF
Capacity
(MGD)
Current
Reuse
Amount
(MGD)
Irrigation Application
Heeia R-2 1.8 0.5
Kona and Alii Country Club Golf
Course
Waikoloa Beach
Resort R-2 1.3 0.5
Waikoloa Beach Resort Golf
Course
Maunalani R-2 0.75 0.25 Nursery and sod farm
South Kohala Resort R-2 0.6 0.27 Mauna Kea Golf Course
Kealakehe R-2 1.3 0.06 Swing Zone Driving Range
Kona International
Airport R-1 0.14 0.03 Landscape
Waimea R-3 0.1 0.045 Parker Ranch pasture
Punaluu R-2 0.125 0.012 Sea Mountain Golf Course
Sources: Department of Health, Wastewater Branch
Water Reuse Projects on Hawaii – List as of January 2005,
<http://www.hwea.org/watreuse/wrhawaii.htm>
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
1.6 EXISTING WATER USE
1.6.1 General
The CWRM staff is working towards establishing and drafting water use categories based on
water system purveyance and primary use of the system for the purposes of water use permitting
and reporting. Upon finalization of the categories, the CWRM staff will propose incorporation
of the categories in the update of the Framework. Water use in this update report is categorized
in accordance with the list and definitions to the extent possible. Future WUDP Updates should
conform to the finalized water use categories to the extent possible.
• Domestic (Individual Household)
• Industrial (Fire Protection, Mining, Thermoelectric Cooling, Geothermal)
• Irrigation (Golf Course, Hotel, Landscape, Parks, School, Dust Control)
• Agriculture (Aquatic Plants & Animals, Crops/Processing, Livestock & Pasture,
Ornamental/Nursery)
• Military
• Municipal (County, State, Private Public Water Systems [as defined by DOH])
Determination of existing water use is difficult due to the lack of detail in available metered
water data, and is therefore based on the best available information. DWS meters customer
water use and therefore has the most complete database on DWS purveyed water use. DWS
metered water data from November 2004 to October 2005 are used in this update. The CWRM
requires a monthly report of water use from wells and stream diversions, with exceptions
discussed in detail in Section 1.6.8.1. CWRM data includes only that which is reported and
therefore is not complete. However, it is the best available data, and data from the same time
period, November 2004 through October 2005, also are used. In addition to the data obtained
from DWS and the CWRM, Federal and State water system managers and private water system
owners were queried on the existing populations served and water production capabilities of their
systems, as well as future projections. Disclosed information is incorporated.
1.6.2 Domestic Use
Domestic use is potable and non-potable water use by individual households. There is no
government agency that oversees private individual systems. The owner is responsible for the
water quantity, quality and maintenance of the system. Individual rainwater catchment systems
and private wells for individual domestic use are in this category. Records and data on
individual rainwater catchment systems are not readily available. Water use by individual
catchment systems is determined by deduction, i.e. if a developed parcel is not served by DWS
or other water system of record, then a catchment system is assumed. Developed areas possibly
served by catchment systems are shown on Figure 1-12. Information on private wells includes
details collected through the CWRM well construction/pump installation permitting process.
Users are required to measure and report monthly usage in excess of 50,000 gallons to the
CWRM.
LEGEND:
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers
1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
Water SystemService Area Map
INDEX MAP - Island of Hawaii
0 4 8 122
Miles
Private Water System Service Area
Possible Catchment Area(Building Value > $10000)
DWS Water System Service Area
Aquifer SystemsHawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-818FIGURE 1-12
DWS Water System
Chapter 1 - Introduction
Page 1-41
Hawaii County
Water Use and Development Plan Update
1.6.3 Industrial Use
Industrial use can be potable or non-potable water use for fire protection, mining, thermoelectric
cooling, and geothermal uses. Most of the industrial use on the island is for thermoelectric
cooling which can use non-potable water; therefore, it is assumed that industrial use is
categorized as non-potable water use. Hawaiian Electric Light Company, Inc. (HELCO) reports
pumpage from their wells to CWRM; therefore an estimate can be made on thermoelectric
cooling by HELCO.
1.6.4 Irrigation Use
The irrigation use category as defined by the CWRM consists of non-potable water uses
including irrigation for golf course, hotel, landscape, parks, school, and dust control. Irrigation
use is determined from CWRM well pumpage data for irrigation wells.
1.6.5 Agricultural Use
Agricultural use includes water use for aquatic plants and animals, crops/processing, livestock
and pasture, and ornamental/nursery, and this does not include water supplied by rainfall.
Aquaculture and some agricultural uses are served by municipal systems.
There is great potential for non-potable agricultural irrigation systems as water sources. The
major systems include the Waimea Irrigation System, Lower Hamakua Ditch System, Kohala
Ditch System, and Kehena Ditch System. However, with the demise of the sugarcane industry in
the late 1990’s, many of the systems were abandoned and left to deteriorate. Current information
on the condition of the systems is limited and typically is obtained by field verification. The
current AWUDP is limited in scope and only discusses two of the systems which are owned and
operated by the State of Hawaii, Department of Agriculture (DOA), Agricultural Resource
Management Division (ARMD), the Waimea Irrigation System and Lower Hamakua Ditch
System (Honokaa-Paauilo Irrigation System). According to the AWUDP, most irrigation
systems built by the sugarcane and pineapple industries in Hawaii did not have any metering or
monitoring of water use. As the industry shifts to diversified agriculture, the lack of water use
data continues. However, the Lalamilo section of the Waimea Irrigation System is one of three
DOA irrigation systems in the State with years of metered monthly diversified agriculture water
use records, as well as acreage served.
The Waimea Irrigation System, Lower Hamakua Ditch System, and Kohala Ditch System are
known to have sustained significant damage from the October 15, 2006 earthquake. The impacts
of this recent event are not fully realized and are not reflected in this report. However, the
earthquake has clearly demonstrated the vulnerability of the ditch systems, and the need for
contingency plans to mitigate the impact of another event.
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Hawaii County
Water Use and Development Plan Update
The United States Department of Agriculture, National Agricultural Statistics Service (USDA,
NASS) collected and published data for the 2002 Census of Agriculture. This was supplemented
by the 2003 Farm and Ranch Irrigation Survey. The census indicates that the County of Hawaii
has 908 farms defined as, “any place from which $1,000 or more of agricultural products were
produced and sold, or normally would have been sold, during the census year;” and also
indicates that 9,041 acres of farmland are irrigated (2002 Census, Table 1). The 2003 Survey,
Table 11, published the Estimated Quantity of Water Applied by Source or Supplier: 2003 and
1998, for the State of Hawaii. A more detailed breakdown of this data was requested from the
USDA, NASS; however, the additional data obtained specific to the County of Hawaii indicates
498 farms and 6,284 acres irrigated with 6,106 acre-feet water (or 5.45 mgd). USDA, NASS
stated that the discrepancy in the information is due to a difference in collecting and
summarizing the data. Due to the discrepancy and uncertain accuracy and completeness of the
survey data, and because more detailed breakdown of the data within the County was not
available, only the 2002 Census of Agriculture data are used.
Current agricultural water use is extremely difficult to determine due to the absence of
comprehensive, island-wide data. Defining existing agricultural water demands is the objective
of the AWUDP, which is a major effort; hence, the AWUDP is being developed in phases. The
WUDP uses the best available information; therefore, agricultural water use considers lands
classified as Important Agricultural Land in the General Plan and the 2002 Census of Agriculture
data. Important Agricultural Lands are defined as “those with better potential for sustained high
agricultural yields because of soil type, climate, topography, or other factors” and have potential
sources of irrigation within reasonable proximity if needed. Therefore, Important Agricultural
Land is used as the primary basis for agricultural water demand. This is discussed further in
detail in Chapter 2, Technical Approach. It is assumed that the 9,041 acres of farmland
currently irrigated on the island are classified as Important Agricultural Land. Accordingly, the
irrigated farmland is divided among each aquifer sector area based on the proportion of the
island’s Important Agricultural Land within each sector area.
1.6.6 Military Use
There are two potable water systems serving military use on the island. The Kilauea Military
Camp, located in the Volcano National Park, relies on an extensive catchment and storage
system. The Pohakuloa Training Area is in the saddle area between the slopes of Mauna Kea,
Mauna Loa, and Hualalai, and is served by the State owned Mauna Kea State Park water system.
1.6.7 Municipal Use
Municipal use includes County, State and Federal water use served by potable water systems,
and private public water systems, as defined by the State Department of Health (DOH). DOH
defines “public water system” as “a system which provides water for human consumption,
through pipes or other constructed conveyances if the system has at least fifteen service
connections or regularly serves an average of at least twenty-five individuals daily at least sixty
days out of the year.” Refer to Figure 1-12, shown previously, for the general service area of the
public water systems on the island. Municipal use is subcategorized into the other CWRM uses,
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
domestic, industrial, irrigation, agriculture and military uses, as data is available. DWS meter
data is the most detailed, but cannot be precisely subcategorized for each use. Domestic use is
based on residential meter data, and is the best defined. Industrial, irrigation and agriculture use
can be identified to an extent. This leaves a considerable portion of water use that cannot be
subcategorized because it is a mix of the subcategories for such users as schools, hotels,
government facilities, etc., and therefore are indicated as “other municipal.” These water
systems are listed in Table 1-10.
Table 1-10: Water Systems
NAME OWNER POP** SVC-CN* SOURCE
Ninole DWS Hawaii 146 51 Ground
Kalapana DWS Hawaii 169 59 Ground
Makapala-Niulii DWS Hawaii 226 79 Ground
Ookala DWS Hawaii 229 80 Ground
Hakalau DWS Hawaii 272 95 Ground
Kapoho DWS Hawaii 283 99 Ground
Kukuihaele DWS Hawaii 455 159 Ground
Halaula DWS Hawaii 526 184 Ground
Honomu DWS Hawaii 621 217 Ground
Paauilo DWS Hawaii 704 246 Ground
Laupahoehoe DWS Hawaii 1,150 402 Ground
Pahala DWS Hawaii 1,316 460 Ground
Pepeeko DWS Hawaii 1,359 475 Ground
Lalamilo DWS Hawaii 1,499 524 Ground
Pahoa DWS Hawaii 1,928 674 Ground
Papaikou DWS Hawaii 2,219 776 Ground
Waiohinu-Naalehu DWS Hawaii 2,225 778 Ground
South Kona DWS Hawaii 2,774 970 Ground
Haina DWS Hawaii 3,312 1,158 Ground
Hawi DWS Hawaii 3,764 1,316 Ground
Olaa-Mountain View DWS Hawaii 5,686 1,988 Ground
Waimea DWS Hawaii 8,872 3,102 Surface
North Kona DWS Hawaii 25,666 8,974 Ground
Hilo DWS Hawaii 37,563 13,134 Ground
Mauna Kea State Park DLNR State Parks 25 13 Surface
Kulani Correctional Facility Department of Public Safety 281 16 Catchment
Kilauea Military Camp*** U.S. Army 220 85 Catchment
Hawaii Volcanoes National Park U.S. Department of Interior 3,374 76 Catchment
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Hawaii County
Water Use and Development Plan Update
Table 1-10: Water Systems (continued)
NAME OWNER POP** SVC-CN* SOURCE
Waikii Ranch Waikii Ranch Homeowners 58 94 Ground
Napuu Water, Inc. Napuu Water, Inc. 330 147 Ground
Mauna Loa Macadamia Nut Mauna Loa Macadamia Nut 100 4 Ground
Punaluu S.M. Investment Partners 200 21 Ground
Kukio Utility Company WB Kukio Resorts, LLC 260 15 Ground
Kohala Ranch Water Co.
Kohala Ranch Water Co.,
LLC 575 250 Ground
Kaupulehu Kaupulehu Water Co. 1,056 9 Ground
Hawaiian Shores Hawaiian Shores Associates 1,132 283 Ground
Hawaiian Beaches Miller & Lieb Water Co. 3,040 950 Ground
Waikoloa West Hawaii Water Co. 8,500 1,436 Ground
*SVC-CN – number of service connections
**POP – population serviced
***Included under “Military Use”
Source: State Department of Health, Safe Drinking Water Branch
1.6.7.1 County Water Systems
The Hawaii County Water Department owns and operates 24 separate systems on the island.
These systems are dispersed widely around the island and vary in size from the largest in Hilo
with 13,134 services (in 2004), to the smallest in Ninole with 51 services. Several of the systems
are interconnected to optimize use of resources. DWS metering data provides the most detailed
water use for the island.
From November 2004 through October 2005, the systems accounted for 25.3 mgd. Descriptions
of the individual water systems are covered in the pertinent aquifer sector sections of this plan.
1.6.7.2 State Water Systems
The State owns two public water systems, the Mauna Kea State Park Water System and the
Kulani Correctional Center Water System. The Mauna Kea State Park WS is located on the
southwestern side of Mauna Kea on Saddle Road. By agreement between the State of Hawaii
Department of Land and Natural Resources (DLNR) and the U.S. Army Pohakuloa Training
Area (PTA), PTA is served by the State owned Mauna Kea State Park WS in exchange for
maintenance of the water system sources and transmission lines. The source for the water
system is from springs. The Kulani Correctional Center Water System is located in Kulani, off
Stainback Highway. The system is supplied by rainwater catchment.
1.6.7.3 Federal Water Systems
There is one Federal water system owned by the Department of the Interior serving the Hawaii
Volcanoes National Park. The system includes extensive catchment and storage facilities.
Addendum No. 1, 2/3/2012
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Hawaii County
Water Use and Development Plan Update
1.6.7.4 Private Public Water Systems
There are ten private public water systems on the island of Hawaii. The largest private water
purveyor on the island is the Waikoloa water system which serves the resort, commercial and
residential properties in the Waikoloa Resort. There are several small systems serving
subdivisions in west Hawaii. There are two small private systems that provide water for
domestic use to the Hawaiian Shores and Hawaiian Beaches subdivisions in Puna. Mauna Loa
Macadamia Nut has a water system south of Hilo, and there is one private system in Punaluu
which serves a golf course, commercial, and residential properties. Some Private Public Water
System water consumption data is available, but is typically difficult to obtain and not
categorized by use. Therefore, water use for Private Public Water Systems is based primarily on
well pumpage reported to CWRM.
1.6.8 Water Use by Resource
Existing water resources include ground water, surface water, rainwater, and reclaimed
wastewater. Most of the available water consumption data are categorized by the type of
resource. As discussed previously, ground water and surface water are described and identified
by hydrologic unit classification and coding systems. Use of water resources from a hydrologic
unit are not limited to use within that hydrologic unit, and may be used within other hydrologic
units when water systems span more than one hydrologic unit.
1.6.8.1 Ground Water
The CWRM has data on well pumpage, which only includes wells for which data are reported.
Consequently, this information is not complete in all areas. The following cases describe uses of
water which are exempt from the requirements for measuring and reporting on a monthly basis
(unless otherwise determined by the CWRM):
a) individual end uses of water on multi-user distribution systems where the end user does not
control or operate the water supply source(s) to the system.
b) water uses from individual systems for average annual uses less than 1,700 gpd.
c) passive agricultural consumption, such as when crops are planted in or adjacent to springs
and natural wetland areas.
d) livestock drinking from dug wells or stream channels;
The following cases allow modification of the monthly reporting requirement, to reporting on a
quarterly, semi-annual, or annual basis:
a) water uses from individual systems for average annual uses equal to or greater than 1,700
gpd and less than 161,000 gpd.
b) salt water or brackish water sources
c) surface water sources
Water uses from gravity-flow, open ditch stream diversion works which are not already being
measured and are not in designated surface water management areas are deferred until the
CWRM adopts reasonable guidelines for such systems.
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
Many of the tunnel and spring sources may be ground water directly under the influence of
surface water (GWUDI). DOH takes samples and performs particulate analysis to determine if
these sources are GWUDI. DOH officials believe that most of the County springs are GWUDI;
however, the only three that have been designated are the Alili Tunnel (DWS Pahala WS), the
Kukuihaele Spring (DWS Kukuihaele WS), and the Olaa Flume (formerly used by the DWS
Hilo WS, currently not in use). GWUDI is subject to the Surface Water Treatment Rule;
however, DOH has granted the two designated GWUDI currently in use “interim disinfection
requirement,” which requires higher disinfection. It is anticipated that DWS will be replacing
GWUDI sources or provide additional treatment
The CWRM database is the best available information and was used to evaluate the existing
ground water resources.
Table 1-11 summarizes the current production, potential production (16 and 24 hour operation),
sustainable yield (SY), and percentage of SY for the various productions calculated. Current
production is represented by the highest 12-month moving average (MAV) calculated from the
actual pumpage data reported for each aquifer system/sector area. Potential well production is
based on installed pump capacities, and calculated for both 16 hours of operation a day (ideal
operating condition) and 24 hours of operation a day. Data is based on pumpage data from
January 2003 through October 2005 reported to CWRM. Many wells in use do not report to
CWRM or are not required to report. Refer to Appendix B for the CWRM well database.
The CWRM well database and sustainable yield information indicate that under current installed
conditions, only the West Mauna Kea Aquifer Sector Area (ASEA), and the Kiholo Aquifer
System Area (ASYA) (within Hualalai ASEA) have the potential of exceeding the sustainable
yield if the wells are operated 24 hours per day; all other sector areas have sufficient sustainable
yield under current installed conditions. Based on the 12-month MAV, actual water withdrawn
from the West Mauna Kea ASEA is 38.04 % of SY and water withdrawn from the Kiholo ASYA
is 22.56% of SY, or 27.77% of SY for the Hualalai ASEA. For the other sector areas, the 12-
month MAV is well under the SY.
Chapter 1 - Introduction Page 1-47 Hawaii County Water Use and Development Plan Update Table 1-11: Well Production and Sustainable Yield Aq Code Sys Code Sector Area System Area High 12-Month MAV (MGD) Potential 16 -Hour Production (MGD) Potential 24-Hour Production (MGD) SY (MGD) High 12-MonthMAV SY (%) Potential 16-Hour ProductionSY (%) Potential 24-Hour ProductionSY (%) 801 Kohala 1.44 17.66 26.49 154 0.94 11.47 17.20 80101 Hawi 0.65 15.23 22.84 27 2.41 56.40 84.59 80102 Waimanu 0.10 0.96 1.44 110 0.09 0.87 1.31 80103 Mahukona 0.69 1.47 2.21 17 4.06 8.67 13.00 802 E. Mauna Kea 2.06 23.86 35.79 388 0.53 6.15 9.22 80201 Honkaa 1.41 2.31 3.46 31 4.55 7.44 11.16 80202 Paauilo 0.14 4.51 6.77 60 0.23 7.52 11.28 80203 Hakalau 0.13 16.17 24.25 150 0.09 10.78 16.17 80204 Onomea 0.38 0.87 1.31 147 0.26 0.59 0.89 803 W. Mauna Kea 9.13 17.56 26.34 24 38.04 73.17 109.75 80301 Waimea 9.13 17.56 26.34 24 38.04 73.17 109.75 804 N.E. Mauna Loa 59.05 62.95 94.43 740 7.98 8.51 12.76 80401 Hilo 42.78 42.15 63.22 347 12.33 12.15 18.22 80402 Keaau 16.27 20.81 31.21 393 4.14 5.29 7.94 805 S.E. Mauna Loa 0.22 5.17 7.75 291 0.08 1.78 2.66 80501 Olaa 0.00 0.00 0.00 124 0.00 0.00 0.00 80502 Kapapala 0.00 0.00 0.00 19 0.00 0.00 0.00 80503 Naalehu 0.22 5.17 7.75 117 0.19 4.42 6.62 80504 Ka Lae 0.00 0.00 0.00 31 0.00 0.00 0.00 806 S.W. Mauna Loa 2.38 6.92 10.38 130 1.83 5.32 7.98 80601 Manuka 0.16 0.79 1.18 42 0.38 1.87 2.81 80602 Kaapuna 0.01 0.40 0.60 50 0.02 0.80 1.20 80603 Kealakekua 2.17 5.73 8.60 38 5.71 15.09 22.63 807 N.W. Mauna Loa 4.13 10.61 15.91 30 13.77 35.36 53.03 80701 Anaehoomalu 4.13 10.61 15.91 30 13.77 35.36 53.03
Chapter 1 - Introduction Page 1-48 Hawaii County Water Use and Development Plan Update Aq Code Sys Code Sector Area System Area High 12-Month MAV (MGD) Potential 16 -Hour Production (MGD) Potential 24-Hour Production (MGD) SY (MGD) High 12-MonthMAV SY (%) Potential 16-Hour ProductionSY (%) Potential 24-Hour ProductionSY (%) 808 Kilauea 1.53 5.53 8.29 618 0.25 0.89 1.34 80801 Pahoa 1.47 3.53 5.30 435 0.34 0.81 1.22 80802 Kalapana 0.06 1.99 2.99 157 0.04 1.27 1.90 80803 Hilina 0.00 0.00 0.00 9 0.00 0.00 0.00 80804 Keaiwa 0.00 0.00 0.00 17 0.00 0.00 0.00 809 Hualalai 15.55 32.79 49.18 56 27.77 58.55 87.82 80901 Keauhou 11.49 16.58 24.87 38 30.24 43.63 65.45 80902 Kiholo 4.06 16.21 24.31 18 22.56 90.04 135.06 Island of Hawaii Total 95.49 183.04 274.56 2431 3.93 7.53 11.29
Chapter 1 - Introduction
Page 1-49
Hawaii County
Water Use and Development Plan Update
1.6.8.2 Surface Water
1.6.8.2.1 Stream Diversions
The inventory of the existing stream diversions was obtained from the CWRM database. The
CWRM database has 197 declared stream diversions and 5 permitted stream diversions. Figure
1-11 shown previously displays the locations and distribution.
In the past, the sugar plantations built several major ditch and flume systems to utilize surface
water sources. According to the Water Resource Protection Plan with data based on information
prior to 1990, approximately 76 mgd were diverted from streams primarily for irrigation and
hydroelectric power serving the sugar industry. Table 1-12 lists the major stream diversions or
ditch systems and corresponding flows.
Table 1-12: Major Stream Diversions
Major Stream Diversion
(Ditch System) Flow (MGD)
Total 76
Kehena Ditch 7
Kohala Ditch 27
Upper Hamakua Ditch 10
Lower Hamakua Ditch 32
The sugar industry has declined steadily since 1983. The last sugarcane harvest on the island
was in 1997, and many irrigation systems were abandoned and left to deteriorate. According to
data published in the State of Hawaii Data Book 2003, Table 5.22 – Fresh Water Use, By Type,
By Counties: 2000 (Data compiled by Hawaii State Department of Business, Economic
Development and Tourism from County of Hawaii Department of Water Supply), surface water
use in 2000 was 8.86 mgd. Surface water remains a significant potential source for irrigation and
industrial uses.
1.6.8.2.2 Instream Use
Instream use is defined by the Code as, “beneficial uses of stream water for significant purposes
which are located in the stream and which are achieved by leaving the water in the stream.
Instream uses include, but are not limited to:
(1) Maintenance of fish and wildlife habitats;
(2) Outdoor recreational activities;
(3) Maintenance of ecosystems such as estuaries, wetlands, and stream vegetation;
(4) Aesthetic values such as waterfalls and scenic waterways;
(5) Navigation;
(6) Instream hydropower generation;
(7) Maintenance of water quality;
Chapter 1 - Introduction
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Hawaii County
Water Use and Development Plan Update
(8) The conveyance of irrigation and domestic water supplies to downstream points of
diversion; and
(9) The protection of traditional and customary Hawaiian rights.”
1.6.8.3 Rainwater Catchment
Rainwater catchment systems are typically located outside of the County water system service
areas. There are three rainwater catchment public water systems regulated by the Department of
Health, Safe Drinking Water Branch. These serve Kilauea Military Camp, Hawaii Volcanoes
National Park and Kulani Correctional Facility. There is no government agency that oversees
private individual systems. The owner is responsible for the water quantity, quality and
maintenance of the system. There are no records or data on these systems. Therefore,
information reflected in this report is based on deductions; i.e. if a developed parcel is not served
by DWS or other water system of record, then a catchment system is assumed. Individual
rainwater catchment systems are primarily in the Puna, Kau and Hamakua Districts.
Where a large number of private individual water catchments exist, the Civil Defense has
established emergency spigots from the County water system to supplement those residents’
needs during droughts. If the County decides to extend water service to these areas, then more
water sources will be needed.
1.6.8.4 Reclaimed Wastewater
Reclaimed wastewater information was obtained from the Department of Health, Wastewater
Branch, as previously listed in Table 1-9. Approximately 1.7 million gallons of reclaimed
wastewater are used per day on the island, primarily for irrigation of agriculture, golf courses and
landscaping.
CHAPTER 2 – TECHNICAL APPROACH
Page 2-1
Hawaii County
Water Use and Development Plan Update
2 TECHNICAL APPROACH
The approach used in the update of the County of Hawaii WUDP was documented in the Project
Description, as required by the Framework. The Project Description was presented to and
approved by the CWRM on September 28, 2005. The approach used involved inventory of
existing water use and resources, projection of water demand for full build-out of land use
policies, and 5-year incremental water demand projections based on rate of population growth to
the year 2025. The Framework requires data and analyses to be based on ground water and
surface water hydrologic units designated by the CWRM; however, due to the developing stage
of the surface water hydrologic units, the WUDP findings described in Chapter 3 are based on
the ground water hydrologic units or aquifer sector areas. The various elements of the approach
are described in this chapter.
Public meetings were held at various stages of development of the WUDP to obtain input from
the public. Four meetings were held in March 2006 in the communities of Hilo, Waimea, Kona
and Naalehu. The methodology described in the following section, preliminary results and
general recommendations were presented at these meetings. Comments received were used to
refine specific elements of the planning methodology. A second series of meetings was held in
July 2007 in the same communities to present the revised WUDP, as well as recommendations
specific to each aquifer sector area. Subsequent to this second series of meetings, the revised
WUDP was posted on the Hawaii County DWS website and comments were accepted for 30
days. Various details were revised within the WUDP based on the comments received; however,
the planning methodology and recommendations were not altered.
2.1 WATER RESOURCES PLANNING METHODOLOGY
Water resource planning for the Hawaii WUDP update considers both land use based water
demand projections and rate of population growth to plan for future water needs. Land use based
evaluations provide full build-out projections, or the ultimate water needs, if the maximum
density allowed is developed. This assesses the sustainability of land use policies set by the
State of Hawaii and the County of Hawaii in terms of the water needs associated with the
potential full build-out development. Incremental water needs for the next 20 years are based on
population and growth rate projections. DWS historical water consumption data are also
evaluated for comparison. Flowcharts diagramming the conceptual planning methodology are
shown in Figures 2-1 and 2-2. Figure 2-3 illustrates a theoretical example of the projected
demands.
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Hawaii County
Water Use and Development Plan Update
Figure 2-1: Full Build-Out Water Demand Projection Methodology
STATE LAND USE
Too general, therefore
not used to determine
water projections.
GENERAL PLAN
LAND USE PATTERN
ALLOCATION GUIDE
(LUPAG)
Policy for long-range
development.
COUNTY ZONING
Legal instrument
which implements the
General Plan with
more detailed
requirements.
GENERAL PLAN
Development Density
(Land Area and Unit
Count)
COUNTY ZONING
Development Density
(Land Area and Unit
Count)
IDENTIFY WATER
RELATED LAND USE
FACTORS
INFORMATION USED TO
REFINE PROJECTIONS
LAND USE
POLICIES
WATER SYSTEM
STANDARDS &
CONSUMPTION
DATA
WATER SYSTEM
STANDARDS &
CONSUMPTION
DATA
DETERMINE WATER
USE UNIT RATES
ULTIMATE WATER
DEMAND BASED ON
THE GENERAL PLAN
POTENTIAL WATER
DEMAND BASED ON
LAND USE ZONING
State DHHL
Special Report #2 - Water
Resources
Agricultural Water Use and
Development Plan
State Water Projects Plan
Other Studies
ESTIMATE FULL
BUILD-OUT WATER
DEMAND
Chapter 2 – Technical Approach
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Hawaii County
Water Use and Development Plan Update
Figure 2-2: 5-Year Incremental Water Demand Projection Methodology
DETERMINE
WATER USE
RATES
PROJECT
HIGH
GROWTH
WATER
DEMAND BY
PERIOD
2005 2010
2015 2020 2025
POPULATION AND
GROWTH RATE
PROJECTION BY
REGION/USE
AREA
HISTORICAL WATER
CONSUMPTION
DATA
(Regression Analyses)
PROJECTED TO
2005 2010
2015 2020 2025
EXISTING WATER
DEMAND
2005 (PRESENT)
Based on available consumption data
WATER SYSTEM STANDARDS &
CONSUMPTION DATA
20-YEAR
INCREMENTAL
WATER DEMAND
PROJECTIONS
POPULATION AND GROWTH RATE PROJECTION
High, Medium and Low Growth Scenarios
PROJECT
MEDIUM
GROWTH
WATER
DEMAND BY
PERIOD
2005 2010
2015 2020 2025
PROJECT
LOW
GROWTH
WATER
DEMAND BY
PERIOD
2005 2010
2015 2020 2025
Chapter 2 - Technical Approach
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Hawaii County
Water Use and Development Plan Update
Figure 2-3: Theoretical Projected Demand
ULTIMATE WATER DEMAND BASED ON THE GENERAL PLAN
POTENTIAL WATER DEMAND BASED ON LAND USE ZONING
PROJECTED
WATER DEMAND
PROJECTED
POPULATION
GROWTH
EXISTING
DEMAND
DEMAND (MGD)EXISTING
POPULATION
2005 2010 2015 2020 2025 POPULATION
2.1.1 Full Build-Out Water Demand Projections
The full build-out water demand projections are land use based. The State Land Use
classification has no guidelines to identify the level of development densities within the various
districts, and therefore is not used for water demand projections. The County General Plan and
County Zoning Land Use classifications are assessed to estimate the projected development
densities for each designation at full-build out. The results are used to project the ultimate water
demand based on the General Plan, and potential water demand based on land use zoning.
2.1.1.1 Hawaii County General Plan
The General Plan provides the ultimate full-build out water demand projection to determine if
there are adequate water resources to sustain the land use pattern adopted by the County.
Although the General Plan is more detailed than the State Land Use classification, the land use
designations are broad, and density guidelines are only provided for the Urban designations, as
listed below:
High Density Urban – up to 87 units per acre
Medium Density – up to 35 units per acre
Low Density – up to 6 units per acre
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Hawaii County
Water Use and Development Plan Update
In addition, Urban Expansion covers a considerable area in comparison to the other Urban
designations. The Urban Expansion designation “allows for a mix of high density, medium
density, low density, industrial, industrial-commercial and/or open designations…” The Urban
Expansion Area has the potential to be developed as High Density Urban, which would
drastically increase the unit count projections; or it could be developed as low as the Low
Density unit count. However, for planning purposes, the density of the Urban Expansion Area
was calculated for each aquifer sector area as the weighted average of Low, Medium, and High
Density Urban unit counts based on the proportion of each urban designation within the specific
aquifer sector area. Unit counts are multiplied by the appropriate residential water use unit rate
to determine the corresponding water demand.
Table 2-1: Proposed Urban Expansion Density Rates
Aquifer
Sector Area
Urban Expansion Density
(units/acre)
801 10.0
802 8.4
803 11.3
804 15.4
805 13.3
806 12.5
807 12.5
808 7.8
809 15.9
The Rural designation is a new designation added to the 2005 General Plan and “includes
existing subdivisions in the State Land Use Agricultural and Rural districts that have a
significant residential component. Typical lot sizes vary from 9,000 square feet to two acres.”
Water projections for Rural areas assume 1 unit per acre multiplied by the appropriate residential
water use unit rate.
The General Plan has three designations for Agriculture: Important Agricultural Land, Extensive
Agriculture, and Orchard, depicted on Figure 2-4, and defined as follows:
Important Agricultural Land: Those with better potential for sustained high agricultural
yields because of soil type, climate, topography, or other factors.
Some areas that meet the criteria for important agricultural lands on an irrigated basis
only were included in the “Extensive Agriculture” category due to their remoteness from
potential sources of irrigation.
Extensive Agriculture: Lands not classified as Important Agricultural Land. Includes
lands that are not capable of producing sustained, high agricultural yields without the
intensive application of modern farming methods and technologies due to certain
physical constraints such as soil composition, slope, machine tillability, and climate.
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Hawaii County
Water Use and Development Plan Update
Other less intensive agricultural uses such as grazing and pasture may be included in the
Extensive Agriculture category.
Orchard: Those agricultural lands which though rocky in character and content support
productive macadamia nuts, papaya, citrus and other similar agricultural products.
Extensive Agriculture areas are not economically feasible to irrigate, and the selected uses (e.g.
grazing and pasture) can be sustained by natural rainfall and do not require intensive application
of modern farming methods and technologies. Orchard crops are typically sustained by rainfall
in the region (as indicated by the lack of irrigation wells and stream diversions in the region).
Therefore, water demands are not allocated to Extensive Agriculture and Orchard.
The Important Agricultural Land designation is a new designation added to the 2005 General
Plan. As stated earlier, Important Agricultural Land has the potential for sustained high
agricultural yields, and there are potential sources of irrigation within reasonable proximity if
needed. Therefore, agricultural water demand is based on the Important Agricultural Land area
multiplied by the agricultural water use unit rate discussed in Section 2.1.1.3.3.
The proposed methodology to determine agricultural water use was met with strong objection at
public meetings. Overwhelmingly, public input suggested that the need for irrigation water was
not predicated on the classification of Agricultural lands. Public input further suggested that
agricultural users would grow what is feasible according to the climate, and that irrigation from
groundwater sources would be minimal. For example, crops requiring large amounts of moisture
would be grown in areas that have a higher ambient rainfall. Commenters recommended that
more realistic agricultural water use unit rates be developed based on historical demands and
existing land use. However, such an undertaking would be extremely difficult due to the lack of
comprehensive, island-wide data. Projecting agricultural water use is the objective of the
AWUDP, which is a major effort; hence, the AWUDP is being developed in phases. The WUDP
uses the best available information; therefore, two agricultural water use scenarios are presented
for each of the full build-out scenarios (Hawaii County General Plan, and Hawaii County
Zoning) and the 5-year incremental water demand projection scenario. This identifies a range of
agricultural water use, which considers the best and worst case scenarios on an interim basis,
until the next phase of the AWUDP is complete.
Chapter 2 – Technical Approach
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Hawaii County
Water Use and Development Plan Update
Figure 2-4: General Plan Agricultural Designations and Surface Water Sources
MAP CURRENTLY NOT AVAILABLE ON-LINE
Chapter 2 – Technical Approach
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Hawaii County
Water Use and Development Plan Update
2.1.1.2 Hawaii County Zoning
The Zoning Code is the County’s legal instrument that regulates land development, and
implements the General Plan policies; therefore, zoning must be consistent with the General
Plan. County Zoning is the basis for the potential full-build out water demand, to determine if
there are adequate water resources to sustain the development of land use already zoned. County
Zoning deals with existing conditions and shorter range needs; and the potential full build-out
unit count projection based on zoning is less than the ultimate projection based on the General
Plan. Full build-out water demand projections for residential and resort uses are based on unit
count projections, and commercial and industrial uses are based on land area; both are based on
land area and multiplied by the appropriate water use unit rate. Water demand for lands zoned
for agriculture considers the specific General Plan agricultural designation. Similar to the
projection methodology based on the General Plan, water demand is allocated only to lands
zoned for agriculture which are also within the Important Agricultural Land designation.
2.1.1.3 Refine Land Use Based Projection
As required by the Framework, the WUDP considers the most recent State Water Projects Plan,
and AWUDP forecasts if water requirements are available; and recognizes the current and future
development needs of the Department of Hawaiian Home Lands (DHHL).
2.1.1.3.1 State Water Projects Plan
The State Water Projects Plan (SWPP), dated February 2003, is a water development plan
specific to future State projects through the year 2020. The State projects, with the exception of
lands owned by the Department of Hawaiian Home Lands (DHHL), conform to the County
zoning (and therefore conform to the General Plan). Therefore, the SWPP was not directly used
to refine the land use based projection because the SWPP water projections are accounted for
with the WUDP update methodology. The DHHL projects are addressed separately.
The SWPP indicates that, “Hydrological sectors with unmet SWPP water demands of 1.0 mgd or
greater will be recommended for State source development. It is anticipated that county water
systems will be able to supply the balance of State water demands in all hydrological sectors.”
Therefore, the WUDP indicates State source development to meet State project water demands
of 1.0 mgd or greater. Coordination between appropriate State agencies and the County should
be continued to cooperatively and jointly develop future source requirements, and to provide for
more expeditious and efficient utilization of government resources whenever possible.
2.1.1.3.2 State Department of Hawaiian Home Lands
The DHHL Special Report #2 – Water Resources is a comprehensive report, which evaluates the
existing water supply and systems, and projects the future water needs for DHHL development
on the island. Currently, DHHL lands are primarily zoned for agriculture. According to the
Memorandum of Agreement between the County of Hawaii and the Department of Hawaiian
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Hawaii County
Water Use and Development Plan Update
Home Lands, County zoning cannot override the authority of the Hawaiian Homes Commission
to control the uses of its property. DHHL will determine the zoning for its lands, and the County
Planning Department will modify its zoning map and Land Use Pattern Allocation Guide
accordingly. These modifications and coordination are ongoing. Therefore, water needs for
DHHL lands are not based on existing zoning maps and were evaluated separately. The water
needs were obtained from the Special Report and available updated information from DHHL,
and allocated to the appropriate aquifer sector areas.
2.1.1.3.3 Agricultural Water Use and Development Plan
According to the Framework, “the major objective of the AWUDP is to develop a long-range
management plan that assesses state and private agricultural water use, supply and irrigation
water systems. The plan shall address projected water demands and prioritized rehabilitation of
existing agricultural water systems.” The AWUDP, dated December 2003 and revised
December 2004, is limited in scope due to time and funding constraints; it assesses the needs and
proposes improvements only for the Lower Hamakua Ditch and Upper Hamakua Ditch
(Waimea) Irrigation Systems. There is no discussion on the Kehena and Kohala Ditches, private
irrigation systems, and related factors such as crop types, climatic factors, soil, terrain, etc. The
AWUDP predicts water demands for both systems based on a potential range of irrigated area
and a unit rate of 3,400 gpd/acre. Due to the uncertainty, these projections were not used to
refine projected demands; however, the unit rate of 3,400 gpd/acre was used to calculate
agricultural water demands.
2.1.2 5-Year Incremental Water Demand Projections to the Year 2025
Existing population and water use were calculated as the basis of the water demand projections
to the year 2025. Population and growth rate projections were applied in 5-year increments for
the next 20 years; and have high-growth, medium-growth (base case) and low-growth (the most
conservative) scenarios, as shown on Figure 2-5. (These were not shown on Figure 2-3, for
clarity.) The demands are further differentiated into potable and nonpotable demands in Chapter
3 for each sector area.
It was assumed that population growth, and thus water use, from projects described in the State
Water Project Plan, the State Department of Hawaiian Home Lands and the Agricultural Water
Use and Development Plan are already accounted for by the population projections; therefore,
information from these documents was not used to further refine the 5-year incremental water
demand projections.
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Hawaii County
Water Use and Development Plan Update
Figure 2-5: Projected Demand H-M-L Growth Scenarios
ULTIMATE WATER DEMAND BASED ON THE GENERAL PLAN
POTENTIAL WATER DEMAND BASED ON LAND USE ZONING
EXISTING
DEMAND
DEMAND (MGD)EXISTING
POPULATION
2005 2010 2015 2020 2025 POPULATIONHIGH GROWTH
MEDIUM GROWTH
LOW GROWTH
PROJECTED WATER DEMAND
PROJECTED POPULATION GROWTH
2.1.2.1 Population and Growth Rate Projections
The population projections to the year 2020 are from the Economic Assessment, PKF Hawaii,
January 2000, and were also the basis of the General Plan. The growth rates were derived from
this data. The projection from 2020 to 2025 is based on the same growth rate used for 2015 to
2020 in the General Plan.
2.1.3 Water Use Unit Rates
Water use unit rates were based on the Water System Standards and actual consumption data.
Potable and non-potable water requirements were differentiated where appropriate.
2.1.3.1 Water System Standards
Applicable water use unit rates from the Water System Standards, Table 100-18 – Domestic
Consumption Guidelines, are listed in Table 2-2.
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Hawaii County
Water Use and Development Plan Update
Table 2-2: Water System Standards, Domestic Consumption Guidelines
Zoning Designation Average Daily Demand
RESIDENTIAL:
Single Family or Duplex
Multi-Family Low Rise
Multi-Family High Rise
400 gals/unit
400 gals/unit
400 gals/unit
COMMERCIAL:
Commercial Only
3000 gals/acre
RESORT: 400 gals/unit or 17,000 gal/acre*
LIGHT INDUSTRY: 4000 gals/acre
SCHOOLS, PARKS: 4000 gals/acre or 60 gals/student
AGRICULTURE: 3400 gals/acre**
* Resort ADD of 17,000 gal/acre based on ADD for Maui.
** Agriculture ADD based on AWUDP.
2.1.3.2 Water Consumption Data
Water use unit rates based on actual consumption data for specific geographic regions were
developed by the Hawaii County Department of Water Supply for single family residential
units, as listed below:
South Kohala and North Kona – 2.5 units/lot
South Kona – 1.5 units/lot
Elsewhere – 400 gals/unit
These unit rates result in higher water demand projections as compared to the Water System
Standard unit rates, but are viewed as more realistic based on historic consumption data.
2.1.4 DWS Historical Water Consumption Data Projection
Historical water consumption data for each DWS water system from 1970 to 2003 were used to
project water consumption to the year 2025 for comparison.
2.2 RESOURCE AND FACILITY RECOMMENDATIONS
2.2.1 Water Source Adequacy
2.2.1.1 Full Build-Out
Water demand based on full development of the County General Plan and County Zoning land
use classifications are compared to the sustainable yield of each aquifer sector to determine if the
land use policies can be sustained.
Chapter 2 – Technical Approach
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Hawaii County
Water Use and Development Plan Update
2.2.1.2 Twenty-Year Projection
The 5-year incremental water demand projections to the year 2025 are assessed to estimate the
percentage of the sustainable yield that could be utilized by present and 20-year water
requirements, and are compared to the County General Plan and County Zoning water demand
requirements to assess relative timing of the full build-out scenarios.
2.2.2 Source Development Requirements
2.2.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, is evaluated to meet projected water demands. Reserving the
highest quality of water for the highest valued need, i.e. human consumption, is prudent.
However, economics often govern supply-side management, such that nonpotable water uses are
often served by potable water systems. In most cases, it is not economical to develop a separate
nonpotable water system parallel to an existing potable water system to serve the “lower value”
needs such as irrigation, industrial and agricultural use. However, when conventional potable
water resources become limited and more costly alternative water resource enhancement
measures are necessary, reserving the highest quality of water for the highest value need will
become a more favorable option, and possibly may eventually become a requirement.
Consequently, nonpotable water uses should depend upon available nonpotable water sources
whenever available.
2.2.2.1.1 Conventional Water Resource Measures
Ground water and surface water are typically the most cost-effective means for meeting
projected water demands. Ground water is usually the least costly potable resource because
minimal treatment is required, and monitoring requirements are significantly less in comparison
to surface water resources. Surface water is usually the least costly non-potable resource
because pumping costs are less than for ground water sources; minimal treatment, if any, is
required; and monitoring is not required.
2.2.2.1.2 Alternative Water Resource Enhancement Measures
Alternative water resource enhancement measures are necessary when the conventional water
resources, ground water and surface water, are not available. These alternative measures include
rainwater catchment systems, wastewater reclamation and desalination; and are considered
enhancement measures due to limitations and restrictions on use. Rainwater catchment is not as
reliable as conventional water resources because it is extremely sensitive to the climate. The use
of reclaimed wastewater is limited, and uses must be approved and in close proximity to the
wastewater reclamation facility. Desalination is more costly than conventional water resources,
due to treatment and monitoring requirements. Brackish ground water would often be the
preferred resource for desalination to meet potable water quality because monitoring
requirements are not as stringent and demanding as they are for a surface water source.
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Hawaii County
Water Use and Development Plan Update
However, according to the WRPP, brackish groundwater contributes toward the sustainable yield
of the aquifer; therefore, desalinization of seawater is advantageous because it is not a limited
resource.
2.2.2.2 Demand-Side Management
Demand-side management, including development density control and water conservation, is a
means to meet source development requirements by reducing demand.
2.2.2.2.1 Development Density Control
In area where the potential land use based water demand is projected to exceed the aquifer sector
sustainable yield, land use policies should be reevaluated to ensure that the planned development
density can be sustained. In particular, County zoning should be reassessed because
development in accordance with the Zoning Code already is legally accepted. If the
development density is not reduced, alternative resource enhancement measures would be
required as the aquifer sustainable yield becomes stressed.
2.2.2.2.2 Water Conservation
Reduction in water demand through water conservation cannot solely ensure sufficient source
water to meet demand; however, it is universally recommended that water conservation
programs be implemented to ensure protection of valuable water resources.
Water consumption within the aquifer sector area is presented and compared to established
standards. Average water consumption per connection on the DWS system compares the usage
to the County standard 400 gpd per connection described in Section 2.1.3.1. Average potable
water use per capita considers potable water usage from all sources, including the DWS system,
private water systems and rainwater catchment, divided by the total population within the aquifer
sector area. Comparisons are drawn to the standard range of usage between 100 and 150 gpd per
capita. In sector areas where consumption significantly exceeds the standards, water
conservation is emphasized to reduce consumption into a more reasonable range; thereby
reserving the highest quality of water for the highest valued need.
Water conservation measures are described in the DWS 20-Year Water Master Plan as follows:
Supply side measures include:
Meter Replacement and Repair – Regular maintenance of existing meters and
replacement of failing meters
Non-Revenue Water Analysis – Accounted-for non-revenue water includes line flushing,
reservoir cleaning, fire fighting, sewer flushing and street cleaning. Unaccounted-for
non-revenue water includes leaks, unauthorized use, inaccurate metering and inaccurate
billing.
Leak Detection Program – Installation of permaloggers, monitoring and repair of
identified leaks.
Chapter 2 – Technical Approach
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Hawaii County
Water Use and Development Plan Update
Storage Tank Automatic Level Controls – Use of automatic level-control valves at
storage facilities to prevent losses and overflows.
Demand side measures include:
Meter Replacement and Repair – Regular maintenance of existing meters and
replacement of failing meters
Plumbing Code Regulation – New developments required to use low-flow and energy
efficient plumbing fixtures.
Voluntary Water Reduction – Issue conservation notices in local newspapers during
times of drought or low water conditions.
Public Outreach/Education Program – Inform, educate and gain support from the public
through informational brochures.
Xeriscape and Efficient Landscaping – Utilize native, low-water-use plants and
vegetation for landscaping and promote efficient use of water for landscaping.
Strict demand side measures such as water restrictions and a stepped rate structure that would
charge higher usage unit rates for larger users may be prudent in critical areas.
Other demand side conservation measures could consider requirement of neighborhood
development and new construction to be LEED (Leadership in Energy and Environmental
Design) certified. LEED is a nationally accepted rating system developed by the U.S. Green
Building Council that recognizes performance in five key areas of human and environmental
health, one of which is water savings.
2.3 LIMITATIONS
Fulfillment of the Framework requirements for the WUDP update requires significant
information, much of which is not available at this time. Therefore, the WUDP should be
viewed as a dynamic document and tool which needs to be updated regularly, and becomes a
more detailed working document as more information and data become available.
2.3.1 Hawaii Water Plan Update
Phase 3 of the Agricultural WUDP is in progress and ultimately will provide agricultural water
demand projections, information on irrigation water systems, and consideration of related factors
such as crop types, climatic factors, soil, terrain, etc. The Water Resource Protection Plan
update also is in progress and will have modified sustainable yield information to better assess
water use within the aquifer sectors.
2.3.2 Water Use Data
Water use data based on the CWRM categories is needed to fulfill the Framework objective.
DWS water meter data is the most detailed consumption data available; however, all of the
consumption data cannot be clearly defined by the CWRM categories. Consumption data for
private public water systems and for individual household catchment systems are needed.
Chapter 2 - Technical Approach
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Hawaii County
Water Use and Development Plan Update
Finally, water use data will be as accurate as the accuracy of meters used, and system losses are
typically not quantified.
2.3.3 CWRM Well and Pumpage Database
Update of the well database would help to better assess which wells are no longer in use, change
of ownership, change of use, etc. Pumpage data for all wells would provide more precise
information on actual impact on the aquifer sustainable yields.
2.3.4 CWRM Stream Diversion Database
There is minimal information available on stream diversions; therefore, the impact of surface
water use is difficult to assess.
CHAPTER 3 – SECTOR REPORTS
Page 3-1
Hawaii County
Water Use and Development Plan Update
3 SECTOR REPORTS
The following Chapters focus on each individual aquifer sector area, presenting background
information categorized as shown in Chapter 1, and following the technical approach to water
resources planning as described in Chapter 2.
801 Kohala Aquifer Sector Area
Page 801-1
Hawaii County
Water Use and Development Plan Update
801 KOHALA AQUIFER SECTOR AREA
801.1 SECTOR AREA PROFILE
801.1.1 General
The Kohala Aquifer Sector Area (ASEA) includes the Hawi [80101], Waimanu [80102] and
Mahukona [80103] Aquifer System Areas (ASYA), capturing the entire North Kohala district,
the northern section of the South Kohala district, and the northeastern tip of the Hamakua
district. The southern boundary of the sector stretches from Kawaihae on the leeward coast to
Waipio Bay. The sector area includes the Kohala Mountain range and most of Waimea Village.
Rainfall is extremely variable throughout the sector area. The heaviest rainfall of 200 inches per
year is on the mountain top while the dry western or leeward slopes of the Kohala Mountain
have annual average rainfall of about 10 inches along the coast. The Waimanu ASYA receives
the most rainfall, and thus has the highest sustainable yield of 110 mgd. The Mahukona ASYA
encompasses the drier leeward side and accordingly has a SY of 17 mgd. The Hawi ASYA has a
SY of 27 mgd. The total SY of the Kohala ASEA is 154 mgd.
801.1.2 Economy and Population
801.1.2.1 Economy
Ranching (especially cattle), macadamia nut production, and nursery products continue to be the
principal agricultural activities within the Kohala ASEA. The 8,500-acre Kahua Ranch is home
to 2,000 cows and 1,500 sheep, and also welcomes over 5,500 visitors a year. The majority of
the land formerly in sugar is now utilized for grazing purposes. Truck crops are also grown on
smaller tracts.
Tourism and the continuing development of resort complexes and related industries are another
important source of income and employment. Plans for a 240-unit resort and residential
development have been developed by Chalon International, Inc., one of the major landowners in
the sector. North Kohala’s abundant natural and historic amenities have also contributed to the
tourist industry.
The W.M. Keck Observatory has its headquarters on land in Waimea within the Kohala ASEA
donated by Parker Ranch. The observatory on Mauna Kea holds the twin Keck Telescopes, the
world’s largest optical and infrared telescopes. Keck employs 125 full-time employees and has
an annual operating budget of $11 million.
The Upolu Airport, located three miles northwest of Hawi, is used occasionally by sightseeing
air taxis and flight training activities; however, there are no regularly scheduled commercial
flights.
801 Kohala Aquifer Sector Area
Page 801-2
Hawaii County
Water Use and Development Plan Update
801.1.2.2 Population
The population contributing to the demand within the Kohala ASEA is from the North Kohala
District and the Waimea Village section of the South Kohala District. The significant growth in
population in the sector area over the last 20 years can be attributed to the growth in tourism,
influx of retirees and other entrepreneurial activities in North Kohala. Additionally, many
residents of North Kohala are employed in South Kohala, which has also experienced significant
growth in tourism.
Table 801-1: Historical Population
1980 1990 2000
1980-90
% Change
1990-2000
% Change
5,133 7,807 11,000 52.1 40.9
Data Source: 2000 U.S. Census
Data redistributed and evaluated for Kohala Aquifer Sector Area
Table 801-2: Population Projection
Growth
Rate 2000 2005 2010 2015 2020
2000-10
% Change
2010-20
% Change
A – Low 11,000 12,447 14,569 17,021 19,913 32.4 36.7
B – Medium 11,000 12,487 14,697 17,271 20,309 33.6 38.2
C – High 11,000 13,008 15,618 18,628 22,140 42.0 41.8
Data Source: County General Plan, February 2005
Data redistributed and evaluated for Kohala Aquifer Sector Area
801.1.3 Land Use
801.1.3.1 Hawaii County General Plan
The Hawaii County General Plan Land Use Pattern Allocation Guide Map for the Kohala ASEA
is shown on Figure 801-1. The estimated land use allocation acreage for each LUPAG
designation within the sector area is listed in Table 801-3.
801 Kohala Aquifer Sector Area
Page 801-5
Hawaii County
Water Use and Development Plan Update
Table 801-3: LUPAG Map Estimated Land Use Allocation Acreage – Kohala Aquifer
Sector Area
LAND USE PATTERN ACREAGE
% of
TOTAL
High Density Urban 0 0
Medium Density Urban 795 0.5
Low Density Urban 4,596 3.2
Industrial 854 0.6
Important Agricultural Land 50,712 32.9
Extensive Agriculture 41,016 26.6
Orchard 0 0
Rural 735 0.5
Resort/Resort Node 47 0.0
Open 2,930 1.9
Conservation 49,869 32.3
Urban Expansion 2,297 1.5
University Use 0 0
TOTAL 154,211 100.0
The water utility courses of action for North Kohala in the Hawaii County General Plan are as
follows:
(a) Pursue a groundwater source for the Makapala-Keokea water system.
(b) Explore further sources for future needs.
(c) Improve and replace inadequate distribution mains and storage facilities.
(d) Encourage efforts to improve the Kohala ditch system and its use for agricultural
purposes.
The water utility course of action for South Kohala in the Hawaii County General Plan relevant
to the Kohala ASEA is as follows:
(e) Continue to seek groundwater sources for the Waimea system.
801.1.3.2 Hawaii County Zoning
Hawaii County Zoning for the Kohala ASEA is shown on Figure 801-2. The estimated land use
allocation acreage for each zoning class within the sector area is listed in Table 801-4.
801 Kohala Aquifer Sector Area
Page 801-6
Hawaii County
Water Use and Development Plan Update
Table 801-4: County Zoning Estimated Class Allocation Acreage – Kohala Aquifer Sector
Area
ZONING CLASS ACREAGE
% of
TOTAL
Single Family Residential 1,923 1.2
Multi-Family Residential
(including duplex) 212 0.1
Residential-Commercial Mixed Use 0 0
Resort 28 0.0
Commercial 297 0.2
Industrial 271 0.2
Industrial-Commercial Mixed 0 0
Family Agriculture 26 0.0
Residential Agriculture 124 0.1
Agriculture 99,770 64.7
Open 963 0.6
Project District 0 0
Forest Reserve 49,289 32.0
(road) 1,307 0.9
TOTAL 154,210 100.0
801.2 EXISTING WATER RESOURCES
801.2.1 Ground Water
The Kohala ASEA has a sustainable yield of 154 mgd. According to the CWRM database, there
are 63 production wells in the sector area, including 18 municipal, 1 domestic, 3 industrial, 33
irrigation and 8 categorized as “other”; however, only 5 wells reported pumpage. The majority
of these wells are tunnels or shafts. There are also 30 wells drilled and categorized as “unused.
Refer to Appendix B for this database. Figure 801-3 shows the well locations.
801.2.2 Surface Water
There are 40 streams in the Kohala ASEA classified as perennial, of which 34 are considered
continuous and 6 are considered intermittent. Seven of the 12 active gages on the island
operated by the USGS are located in the sector area. Flow data from these gages were
previously listed in Table 1-8.
There are 101 declared stream diversions in CRWM database in the sector area shown on Figure
801-4, which accounts for half of the declared stream diversions on the island. The stream
diversions with declared flows are listed in Table 801-5.
LEGEND:Hawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-8182 0 21
Miles
Agricultural - 1 thru 10 acresAgricultural - 20 acresAgricultural - 35 acresAgricultural - 40 acresAgricultural - 80 acresAgricultural - 200 thru 255 acresAgricultural - 500 acresAgricultural - 600 acresAgricultural - 800 acresAgricultural - 900 acresAgricultural Project DistrictsDowntown Hilo Commercial DistrictCommercial, GeneralCommercial, NeighborhoodCommercial, VillageFamily AgriculturalForest ReserseIndustrial - CommercialIndustrial, GeneralIndustrial, LimitedOpenProject DistrictsResidentail and AgriculturalResidential - Commercial Mixed UseResidential Double-FamilyRes. Multi-Family - 7500-8000 sfRes. Multi-Family - 14,500-20,000 sfRes. Single Family - 7500-10,000 sfRes. Single Family - 15,000-20,000 sfHotel/Resort
Zoning Designations:
A-1a+A-20aA-35aA-40aA-80aA-200+A-500aA-600aA-800aA-900aAPDCDHCGCNCVFAFRMCXMGMLOPDRARCXRDRM-7.5+RM-14.5+RS-7.5+RS-15+V
Developed ParcelsHawaiian Home Lands
P A C I F I C O C E A N
Mahukona80103
Kawaihae Bay
Waimanu80102
Hawi80101
Upolu Pt.
Akoakoa Pt.
Waipio Bay
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
INDEX MAP - Island of Hawaii
County Zoning
FIGURE 801-2
AQUIFER SECTORKOHALA - 801Aquifer SystemsHawi - 80101Waimanu - 80102Mahukona - 80103
801 Kohala Aquifer Sector Area
Page 801-9
Hawaii County
Water Use and Development Plan Update
Figure 801-3: Well and Tunnel Location
MAP CURRENTLY NOT AVAILABLE ON-LINE
801 Kohala Aquifer Sector Area
Page 801-11
Hawaii County
Water Use and Development Plan Update
Figure 801-4: Streams & Diversions
MAP CURRENTLY NOT AVAILABLE ON-LINE
801 Kohala Aquifer Sector Area
Page 801-13
Hawaii County
Water Use and Development Plan Update
Table 801-5: Stream Diversions – Kohala Aquifer Sector Area
FILE REFERENCE TMK STREAM NAME
CHALON INT 5-2-004:003 Puwaiole Gulch
Stream diversion, Intake #9 from Puwaiole Stream.
Temporarily damaged. Declared Q of 5.849 is the total for
Hawi Weir.
CHALON INT 5-2-005:001 Waipuni Gulch
Stream diversion, Intake #7 from Waipuhi Stream to Kohala
Ditch. Declared Q of 5.849 is the total for Hawi Weir;
Verified Q is estimated from flow velocity.
CHALON INT 5-2-005:001 Niulii Stream diversion, Intake #5 from Niulii Stream to Kohala
Ditch. Declared Q of 2.571 is the total for Niulii Weir.
CHALON INT 5-2-005:001 Waikani Gulch
Stream diversion, Intake #6 from Waikane Stream to Kohala
Ditch. Declared Q of 5.849 is the total for Hawi Weir;
Verified Q is estimated from flow velocity.
CHALON INT 5-2-005:001 Waikama Gulch Stream diversion, Intake #3 - Waikama Stream to Kohala
Ditch. Declared Q of 2.571 is the total for Niulii Weir.
CHALON INT 5-2-005:001 Waikama Gulch
Stream diversion, Intake #4 - Waikama Stream to Kohala
Ditch. Declared Q of 2.571 is the total for Niulii Weir; Verified
Q is estimated from flow velocity.
CHALON INT 5-2-006:003 Waipunalau Gulch
Stream diversion, Intake #8, Waipunalau Stream to Kohala
Ditch. Declared Q of 5.849 is the total for Hawi Weir;
Verified Q is estimated from flow velocity.
CHALON INT 5-3-002:001 Halawa Gulch
Stream diversion, Intake #11 from Halawa Stream. Declared
Q of 5.849 is the total for Hawi Weir. Intake is damaged. No
flow observed during field verification.
CHALON INT 5-3-002:001 Walaohia Gulch
Stream diversion, Intake #10 from Walaohia Stream.
Declared Q of 5.849 is the total for Hawi Weir. Intake is
damaged.
CHALON INT 5-3-004:001 Waiakanaua Gulch Stream diversion, Intake #12 Waiakauaua Stream to Kohala
Ditch. Declared Q of 5.849 is the total for Hawi Weir.
CHALON INT 5-3-005:006 Hapahapai Gulch Stream diversion, Intake #14 from Hapahapai. Unused.
Declared Q of 5.849 is the total for Hawi Weir.
HAMAKUA SUGAR 4-8-003:006 Hiilawe
Stream diversion, Hiilawe Stream Intake to Lalakea System.
Declared Q of 912 MG is the total for three intakes to the
Lalakea System.
HAMAKUA SUGAR 4-8-003:006 Hakalaoa
Stream diversion, Hakalaoa Stream Intake to Lalakea
System. Declared Q of 912 MG is the total for three intakes
to the Lalakea System.
HAMAKUA SUGAR 4-8-003:006 Lalakea
Stream diversion, Lalakea Intake to Lalakea System.
Declared Q of 912 MG is the total for three intakes to the
Lalakea System.
CRANE J 4-9-010:020 Waiola
Stream diversion, flume from Wailoa Side Stream. Declared
Q of 292 MG includes both of declarant's diversions. See
new entry created for diversion from waterfall. Declarations
were submitted in 1990.
CRANE J 4-9-010:020 Unnamed
Stream diversion, Unnamed waterfall (new entry). Declared
Q of 292 MG includes both of declarant's diversions. See
other entry for flume. Declarations were submitted in 1990.
RATHBUN C 4-9-011:002 Wailoa Stream diversion, main auwai from Wailoa Stream. Declared
Q = 48 cubic ft per second.
HAMAKUA SUGAR 4-9-012:001 Alakahi
Stream diversion, Alakahi Stream Intake to Lower Hamakua
Ditch. Declared Q of 11,000 MG is the total for four intakes to
Hamakua Ditch.
801 Kohala Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
HAMAKUA SUGAR 4-9-012:001 Kawainui
Stream diversion, Kawainui Stream Intake to Lower
Hamakua Ditch. Declared Q of 11,000 MG is the total for four
intakes to Hamakua Ditch.
HAMAKUA SUGAR 4-9-012:001 Koiawe
Stream diversion, Kaiawe Stream Intake to Lower Hamakua
Ditch. Declared Q of 11,000 MG is the total for four intakes to
Hamakua Ditch.
HAMAKUA SUGAR 4-9-012:001 Waiama
Stream diversion, Waima Stream Intake to Lower Hamakua
Ditch. Declared Q of 11,000 MG is the total for four intakes to
Hamakua Ditch.
CHALON INT 5-1-001:004 Honokane Nui East
Branch
Stream diversion, Honokane Dam Main Intake. East Branch
to Kohala Ditch. Declared Q of 2.571 is the total for Niulii
Weir
CHALON INT 5-1-001:004 Honokane Nui West
Branch
Stream diversion, Intake #2, Honokane Nui West Branch to
Kohala Ditch. Declared Q of 2.571 is the total for Niulii Weir.
CHALON INT 5-1-001:019 Tributary to Pololu
Stream
Stream diversion, Kohala Ditch Trail Intake #B from
Unnamed. Declared Q of 2.571 is the total for Niulii Weir.
Intake "A" is inactive.
CHALON INT 5-1-001:019 Waiakalae Gulch Stream diversion, Twin Falls Intake from Waiakalae Gulch.
Declared Q of 2.571 is the total for Niulii Weir.
STATE DOA HAW 6-3- :004 Kawainui Stream diversion, Kawainui Intake from Kawainui Stream.
Declared Q of 366.671 is the total for all 5 intakes.
STATE DOA HAW 6-3-001:004 Unnamed Stream diversion, Koiawe Intake from comb intake. Declared
Q of 366.671 is the total for all 5 intakes.
STATE DOA HAW 6-3-001:004 Unnamed Stream diversion, Waima Intake from comb intake. Declared
Q of 366.671 is the total for all 5 intakes.
STATE DOA HAW 6-3-001:004 Alakahi Stream diversion, Alakahi Intake from Alakahi Stream.
Declared Q of 366.671 is the total for all 5 intakes.
STATE DOA HAW 6-3-001:004 Kawaiki Stream diversion, Kawaiki Intake from Kawaiki Stream.
Declared Q of 366.671 is the total for all 5 intakes.
PARKER RANCH 6-1-001:004 Keawewai Stream diversion, Keawewai Supply Ditch from Keawewai
Stream. Declared Q = 176,596,950,000 gallons per year.
HAWAII DWS 6-3-001:001 Waikoloa Stream diversion, pipe from Waikoloa Stream. Declared Q of
559.8 is the calculated total for 2 intakes at 1.427 MGD.
HAWAII DWS 6-5-001:011 Kohakohau Stream diversion, Kohakohau Stream Diversion. Declared Q
of 559.8 is the calculated total for 2 intakes at 1.427 MGD.
Stream diversions located in the Kohala ASEA are the sources of flow conveyed by all four of
the County’s major ditch systems.
The Kohala Ditch system originates at the Waikoloa Stream, which lies between Waimanu and
the Honokane Iki valleys, and is known as the Awini Ditch Section. The system was developed
by the former Kohala Plantation to irrigate sugarcane in coastal areas. Since the closure of the
Kohala Sugar Company in 1975, maintenance of the ditch system has been substantially reduced.
Currently, the system is owned by Chalon International of Hawaii; and is used for recreational
purposes and limited agricultural and irrigation activities. Groundwater from dike impounded
and perched systems and surface water are both conveyed by the ditch. Measurements in the
past indicate that the ditch had a maximum capacity of 76 mgd with a mean flow of 23 mgd.
Also developed by the Kohala Plantation, the Kehena Ditch system lies in the upper slopes of the
Kohala Mountain. This system collects water from the stream that feeds Honokane Valley at an
approximate elevation of 4,300 ft, which is transported along the Kohala mountain ridgeline to
801 Kohala Aquifer Sector Area
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Water Use and Development Plan Update
Puuokumau Reservoir located above Kaauhuhu. This system has recorded an average daily flow
of 6 mgd with a maximum capacity of 14 mgd, but faced substantial water loss in the
transportation and storage process. The Kehena Ditch has not been actively maintained since the
1960’s due to a lack of demand.
The Upper Hamakua Ditch is a series of open ditches and tunnels. Its principal water sources are
the summit watersheds of the Kohala Mountain, namely Kawainui, Kawaiki, Alakahi, Koiawe,
and Waima Streams. The first three are the main contributors to the flow. The ditch was
originally constructed to supply water to the Hamakua coast, but was later re-aligned and
diverted into a 60 MG reservoir in Waimea, which supplies the Waimea Irrigation System. The
ditch is able to handle flows in excess of 30 mgd according to past records of the Hamakua
plantation.
The Lower Hamakua Ditch currently utilizes three intakes at the Kawainui, Alakahi, and Koiawe
Streams in the Waipio Valley. A fourth, the Waima Intake, is expected to be re-activated. A
series of transmission tunnels along the Waipio Valley cliff face transport water to the ditch
system in the East Mauna Kea ASEA (802). According to a study conducted by the USGS, a
gage located 500 feet upstream of the Kukuihaele Weir recorded an average flow of 6.5 mgd in
2003.
The DWS Waimea WS utilizes dam diversions of the Waikoloa Stream and the Kohakohau
Stream. The 2006 DWS 20-Year Water Master Plan indicates the estimated capacity of the
surface water sources used by the water system to be 1.45 mgd.
801.2.3 Reclaimed Wastewater
There are no wastewater reclamation facilities (WWRF) in the study area.
801.3 EXISTING WATER USE
801.3.1 General
The following section presents the total estimated average water use within the Kohala ASEA,
and the Hawi, Waimanu, and Mahukona ASYAs separately. Estimated water use from 2004 to
2005 was estimated using (DWS meter data and CWRM pumpage data from November 2004
through October 2005, and available GIS data) and are listed in Tables 801-6, 801-6a, 801-6b,
and 801-6c for the sector and system areas, respectively. Tables 801-6, 801-6a, 801-6b, and
801-6c and Figures 801-5, 801-5a, 801-5b, and 801-5c summarize water use in accordance with
CWRM categories. The tables and figures also indicate separately the quantities supplied
excluding agricultural demands, and the quantities supplied including worst case agricultural
demands (as described in Chapter 2) by the DWS system, and non-DWS systems for the sector
area and system areas, respectively.
801 Kohala Aquifer Sector Area
Page 801-16
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Water Use and Development Plan Update
Table 801-6: Existing Water Use by Categories – Kohala Aquifer Sector Area
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.11 4.9 1.8
Industrial 0.00 0.0 0.0
Irrigation 0.00 0.0 0.0
Reclaimed WW 0.00 0.0 0.0
Agriculture 4.16 0.0 64.2
Military 0.00 0.0 0.0
Municipal
DWS System 1.53 65.8 23.6
Private Public WS 0.68 29.3 10.5
Total without Ag 2.32 100.0
Total with Ag 6.48 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 801-5: Existing Water Use by Categories – Kohala Aquifer Sector Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Domestic 4.9%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 29.3%
Municipal
(DWS) 65.8%
Domestic 1.8%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 64.2%
Military 0.0%
Municipal
(Non-DWS) 10.5%
Municipal
(DWS) 23.6%
w/o Agricultural Water Use* with Agricultural Water Use*
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Water Use and Development Plan Update
Table 801-6a: Existing Water Use by Categories – Hawi Aquifer System Area [80101]
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.03 5.9 1.4
Industrial 0.00 0.0 0.0
Irrigation 0.00 0.0 0.0
Reclaimed WW 0.00 0.0 0.0
Agriculture 1.68 0.0 76.0
Military 0.00 0.0 0.0
Municipal
DWS System 0.50 94.1 22.6
Private Public WS 0.00 0.0 0.0
Total without Ag 0.53 100.0
Total with Ag 2.21 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 801-5a: Existing Water Use by Categories – Hawi Aquifer System Area [80101]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Domestic 5.9%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 0.0%
Municipal
(DWS) 94.1%
Domestic 1.4%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 76.0%
Military 0.0%
Municipal
(Non-DWS) 0.0%Municipal
(DWS) 22.6%
w/o Agricultural Water Use* with Agricultural Water Use*
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Table 801-6b: Existing Water Use by Categories – Waimanu Aquifer System Area [80102]
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.02 20.2 5.8
Industrial 0.00 0.0 0.0
Irrigation 0.00 0.0 0.0
Reclaimed WW 0.00 0.0 0.0
Agriculture 0.24 0.0 71.1
Military 0.00 0.0 0.0
Municipal
DWS System 0.08 79.8 23.0
Private Public WS 0.00 0.0 0.0
Total without Ag 0.10 100.0
Total with Ag 0.34 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 801-5b: Existing Water Use by Categories – Waimanu Aquifer System Area
[80102]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Domestic 20.2%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 0.0%
Municipal
(DWS) 79.8%
Domestic 5.8%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 71.1%
Military 0.0%
Municipal
(Non-DWS) 0.0%
Municipal
(DWS) 23.0%
w/o Agricultural Water Use* with Agricultural Water Use*
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Table 801-6c: Existing Water Use by Categories – Mahukona Aquifer System Area [80103]
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.06 3.8 1.6
Industrial 0.00 0.0 0.0
Irrigation 0.00 0.0 0.0
Reclaimed WW 0.00 0.0 0.0
Agriculture 2.24 0.0 57.0
Military 0.00 0.0 0.0
Municipal
DWS System 0.95 56.1 24.1
Private Public WS 0.68 40.2 17.3
Total without Ag 1.69 100.0
Total with Ag 3.94 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 801-5c: Existing Water Use by Categories – Mahukona Aquifer System Area
[80103]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 801-6 generally shows the service area for the various water systems and indicates the
extent of the DWS water system.
Domestic 3.8%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 40.2%
Municipal
(DWS) 56.1%Domestic 1.6%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 57.0%
Military 0.0%
Municipal
(Non-DWS) 17.3%
Municipal
(DWS) 24.1%
w/o Agricultural Water Use* with Agricultural Water Use*
801 Kohala Aquifer Sector Area
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801.3.2 Domestic Use
Domestic use or water use by individual households is nominal, and is assumed to be supplied by
private individual rainwater catchment systems.
801.3.3 Industrial Use
There are three wells classified as “Industrial” in the CWRM well database, however none
reported pumpage. The hydroelectric plant located just west of Hawi is one of the primary users
of the Kohala Ditch, however actual consumption is not known.
801.3.4 Irrigation Use
There are no known irrigation uses dedicated to golf course or other landscaping activities.
801.3.5 Agricultural Use
Kahua Ranch’s water resources include a series of stream diversions, tunnel intakes, and one
deep well. The main sources are the stream intakes. The two large intakes are the Kahua
Watershed at elevation 4,173 ft, and the Kehena Ditch source. Both sources are subject to dry
weather conditions which can substantially reduce stream flows. Storage tanks are necessary for
ranch operations.
The Kohala Ditch is also utilized for aquacultural and agricultural purposes. According to the
AWUDP, little is known of the service areas of the Kohala Ditch; although in areas along the
coast and near Hawi ditch, flow is utilized for agricultural uses developed by the Kohala
Agricultural Task Force.
801.3.6 Military Use
There is no military use within the Kohala ASEA.
801.3.7 Municipal Use
Municipal use can be subcategorized into the other water use categories, namely Domestic,
Industrial, Irrigation, Agriculture, and Military, if detailed information is available.
801.3.7.1 County Water Systems
The DWS has four water systems in the Kohala ASEA.
The Hawi Water System (WS) serves the bulk of the Hawi area in North Kohala along Akoni
Pule Highway and surrounding area from Puakea Bay Drive in the west to Kapaau Road in the
801 Kohala Aquifer Sector Area
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Water Use and Development Plan Update
east. It is comprised of several smaller rural and plantation water systems formerly served by
various sources, including the Kohala Ditch, and the Lindsey, Watt and Hapahapai Tunnels. The
system is currently served by Hawi Deep Wells No. 1 and 2, drilled in 1975 and 1993
respectively. Eight operational zones are served through a combination of three booster pump
stations and five storage tanks. As a result of merging and discontinuation of the tunnel sources,
five other storage tanks in the system are currently not in service.
The Halaula Water System serves Ainakea Village and Halawa. The plantation, as part of its
Halaula employee subdivision, improved the water system in this area and turned it over to the
Water Department. Once supplied by Bond Tunnel No. 1, the system has been interconnected
with and now relies on the Hawi WS to the west for its supply. A single tank maintains the
storage requirements of the system.
The Makapala-Niulii Water System is a small water system serving the residents and small
business firms in the area. These customers were serviced formerly by a plantation system. The
closing of the plantation left this area without a managed water system. With State funds, the old
water system, consisting of galvanized pipelines and small redwood storage tanks, was
renovated. The new system, which began in 1982, also provides fire protection. The system
continues to be supplied by Murphy Tunnel; however, DWS is currently developing a well
source at the Makalapa Tank site on Makalapa Road.
The Waimea Water System extends along Mamalahoa Highway and surrounding areas from
Kawaihae to the two connections to the Haina Water System at the judicial boundary near Mud
Lane. It spans three aquifer sector areas; however, the majority of the service area is within the
Kohala ASEA, including the majority of Waimea Village, and the areas north of Mamalahoa
Highway from Kawaihae to the Kamuela Highlands subdivision. Since 1950, improvements to
the system have increased reservoir capacity, enlarged the distribution pipelines, and extended
the system to meet the growth of this rapidly developing community. The principal sources for
the Waimea Water System are the mountain supplies from Waikoloa Stream, first developed in
1925, and the Kohakohau Stream diversion which was completed in 1971. Today, the system
has been expanded to include seven tanks spanning eight pressure zones. The stream sources
have recently been supplemented by the Parker Ranch well, which taps a high-level groundwater
source. Due to its origin in the wet mountain regions of the Kohala Mountain forest reserve, the
surface water is treated at the Waimea Water Treatment Plant by conventional filtration for odor
and color control, and for corrosion control and disinfection. The surface water is blended with
the groundwater at the WWTP before distribution.
The Waimea area is subject to extremes in climactic conditions as reflected in stream flows of
flood portions at times, and periods of extended low flows during drought weather. For this
reason, the Waimea Water System has four large reservoirs with the combined capacity to store
158.5 million gallons of untreated water.
DWS water use is subcategorized separately for the Kohala ASEA, and the Hawi, Waimanu, and
Mahukona ASYAs in Tables 801-7, 801-7a, 801-7b, and 801-7c to the extent possible based on
available meter data and is depicted in Figures 801-7, 801-7a, 801-7b, and 801-7c, respectively.
801 Kohala Aquifer Sector Area
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Water Use and Development Plan Update
“Other Municipal” includes facilities such as schools, and various commercial, government,
medical and nonprofit entities which have mixed water use and cannot be specifically allocated
to the other categories.
Table 801-7: DWS Existing Water Use by Categories – Kohala Aquifer Sector Area
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 1.11 73.0
Industrial 0.00 0.3
Irrigation 0.00 0.0
Agriculture 0.10 6.4
Military 0.00 0.0
Other Municipal 0.31 20.3
Total 1.53 100.0
Figure 801-7: DWS Existing Water Use by Categories – Kohala Aquifer Sector Area
Domestic 73.0%
Industrial 0.3%
Irrigation 0.0%
Agriculture 6.4%
Military 0.0%
Other Municipal
20.3%
801 Kohala Aquifer Sector Area
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Water Use and Development Plan Update
Table 801-7a: DWS Existing Water Use by Categories – Hawi Aquifer System Area [80101]
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 0.42 83.3
Industrial 0.00 0.0
Irrigation 0.00 0.0
Agriculture 0.04 7.5
Military 0.00 0.0
Other Municipal 0.05 9.2
Total 0.50 100.0
Figure 801-7a: DWS Existing Water Use by Categories – Hawi Aquifer System Area
[80101]
Domestic 83.3%
Industrial 0.0%
Irrigation 0.0%
Agriculture 7.5%
Military 0.0%
Other Municipal
9.2%
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Water Use and Development Plan Update
Table 801-7b: DWS Existing Water Use by Categories – Waimanu Aquifer System Area
[80102]
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 0.07 96.8
Industrial 0.00 0.0
Irrigation 0.00 0.0
Agriculture 0.00 0.0
Military 0.00 0.0
Other Municipal 0.00 3.2
Total 0.08 100.0
Figure 801-7b: DWS Existing Water Use by Categories – Waimanu Aquifer System Area
[80102]
Domestic 96.8%
Industrial 0.0%
Irrigation 0.0%
Agriculture 0.0%
Military 0.0%
Other Municipal
3.2%
801 Kohala Aquifer Sector Area
Page 801-27
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Water Use and Development Plan Update
Table 801-7c: DWS Existing Water Use by Categories – Mahukona Aquifer System Area
[80103]
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 0.62 65.7
Industrial 0.00 0.4
Irrigation 0.00 0.0
Agriculture 0.06 6.3
Military 0.00 0.0
Other Municipal 0.26 27.6
Total 0.95 100.0
Figure 801-7c: DWS Existing Water Use by Categories – Mahukona Aquifer System
Area [80103]
Domestic 65.7%
Industrial 0.4%
Irrigation 0.0%
Agriculture 6.3%
Military 0.0%
Other Municipal
27.6%
801.3.7.2 State Water Systems
The Waimea Irrigation System is owned by the DOA. Flow is diverted from the Upper
Hamakua Ditch into the 60 MG Waimea Reservoir. A second reservoir, the Puu Pulehu
Reservoir, with an increased capacity of 100 MG, provides overflow storage for the Waimea
Reservoir as well as diverted upstream flow. The transmission system includes two miles of 24-
inch and 18-inch diameter pipelines. Distribution to the farm lots in Lalamilo and Puukapu is
mostly in the West Mauna Kea ASEA (803).
801 Kohala Aquifer Sector Area
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Water Use and Development Plan Update
801.3.7.3 Federal Water Systems
There are no Federal water systems in the Kohala ASEA regulated by the DOH.
801.3.7.4 Private Public Water Systems
There is one private public water system within the Kohala ASEA regulated by the Department
of Health. The Kohala Estates/Kohala Joint Venture subdivision initiated by Hilton Head, with
lands purchased from Kahua Ranch, expanded beyond its original scope. The Kohala Ranch
development developed its own water source by drilling 2 deep wells at elevation 1,470 feet.
The wells currently pump an average of 0.68 mgd. The wells are approximately 2.65 miles
inland from the coast and have a chloride content of 35 to 70 ppm according to the CWRM well
database. Two additional wells were drilled and are classified in the CWRM database as
“unused”.
801.3.8 Water Use by Resource
801.3.8.1 Ground Water
Table 801-8 summarizes the current production, potential production (16 and 24 hour operation),
sustainable yield (SY), and percentage of SY for the various productions calculated. Current
production is represented by the highest 12-month moving average (MAV) or the highest annual
average yield calculated from the actual pumpage data. Potential well production is based on
installed pump capacities, and calculated for both 16 hours of operation a day and 24 hours of
operation a day. Data is based on pumpage data reported to CWRM.
Table 801-8: Sustainable Yield – Kohala Aquifer Sector Area
Sys Code System Area
High
12-Month
MAV
(MGD)
Potential
16 -Hour
Production
(MGD)
Potential
24-Hour
Production
(MGD) SY (MGD)
High
12-Month
MAV
SY
(%)
Potential
16-Hour
Production
SY
(%)
Potential
24-Hour
Production
SY
(%)
1.44 17.66 26.49 154 0.94 11.47 17.20
80101 Hawi 0.65 15.23 22.84 27 2.41 56.40 84.59
80102 Waimanu 0.10 0.96 1.44 110 0.09 0.87 1.31
80103 Mahukona 0.69 1.47 2.21 17 4.06 8.67 13.00
As described in Section 801.3.7.1, the DWS Makapala-Niulii Water System in North Kohala
obtains water from Murphy Tunnel. According to DWS records, the amount drawn between
November 2004 and October 2005 was less than 0.01 mgd. The DWS 20-Year Water Master
Plan states that the capacity of the source is 0.1 mgd.
801 Kohala Aquifer Sector Area
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Water Use and Development Plan Update
801.3.8.2 Surface Water
The principal sources of the DWS Waimea Water System are the dam diversions at the Waikoloa
Stream and the Kohakohau Stream. DWS records indicate the amount of surface water drawn
between November 2004 and October 2005 was 1.85 mgd.
The Upper Hamakua Ditch supplies surface water via the Waimea Irrigation System to farm lots
in Lalamilo and Puukapu in the West Mauna Kea ASEA (803). According to the AWUDP, the
pressurized distribution system is metered at each of its 117 accounts, and drew 0.91 mgd in
2003.
801.3.8.3 Rainwater Catchment
Water consumption calculated for developed parcels that are not supplied by groundwater or
surface water is assumed to be supplied by rainwater catchment. The water use previously
categorized as Domestic Use in Table 801-6 is assumed to be supplied by individual catchment
systems.
801.3.8.4 Reclaimed Wastewater
There are no wastewater reclamation facilities in the Kohala ASEA.
801.4 FUTURE WATER NEEDS
801.4.1 General
Table 801-9 summarizes the LUPAG, Zoning and 5-year incremental water demand projection
scenarios for the total aquifer sector area and the individual aquifer system areas. The
sustainable yield (SY) is presented to draw comparisons.
Table 801-9: Summary of Demand Projections
Growth Rate B Demand Projections (mgd)Without
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total Kohala ASEA 154 40.2 8.9 2.3 2.7 3.2 3.7 4.3
80101 – Hawi ASYA 27 6.8 1.1 0.5 0.6 0.8 0.9 1.1
80102 – Waimanu ASYA 110 0.8 0.1 0.1 0.1 0.1 0.1 0.2
80103 – Mahukona ASYA 17 32.6 7.7 1.7 2.0 2.3 2.7 3.1
Growth Rate B Demand Projections (mgd)With
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total Kohala ASEA 154 207.6 174.5 6.5 7.6 8.9 10.5 12.3
80101 – Hawi ASYA 27 74.2 67.7 2.2 2.6 3.2 3.8 4.5
80102 – Waimanu ASYA 110 10.2 9.3 0.3 0.4 0.4 0.5 0.6
80103 – Mahukona ASYA 17 123.2 97.4 3.9 4.6 5.3 6.2 7.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
801 Kohala Aquifer Sector Area
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Water Use and Development Plan Update
LUPAG water demands excluding agricultural demands for the Kohala ASEA are approximately
one-quarter of the sector area’s SY; however, the LUPAG water demands excluding water
demands for the Mahukona ASYA greatly exceed its SY. Analysis of the three demand
projection scenarios will be presented for the aquifer sector area and for each of the aquifer
system areas.
801.4.2 Full Build-Out Water Demand Projections
The full build-out water demand projections based on the General Plan and County Zoning are
listed in Tables 801-10, 801-10a, 801-10b, 801-10c and Tables 801-11, 801-11a, 801-11b, 801-
11c for the sector and system areas, respectively, and reflect refinement as discussed below.
Each land use class is associated with the most appropriate CWRM water use category.
Table 801-10: Hawaii County General Plan Full Build-Out Water Demand Projection –
Kohala Aquifer Sector Area
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 28.5
Urban Expansion Domestic/Irrigation/Municipal 6.5
Resort Irrigation/Municipal 0.8
Industrial Industrial 1.3
Agriculture Agriculture 167.5
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 0.7
DHHL Irrigation/Municipal 2.4
TOTAL w/o Ag* 40.2
TOTAL w/ Ag* 207.6
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 801-11: County Zoning Full Build-Out Water Demand Projection – Kohala Aquifer
Sector Area
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 4.8
Resort Irrigation/Municipal 0.3
Commercial Municipal 0.8
Industrial Industrial 0.6
Agriculture Agriculture 165.6
DHHL Irrigation/Municipal 2.4
TOTAL w/o Ag* 8.9
TOTAL w/ Ag* 174.5
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
801 Kohala Aquifer Sector Area
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Water Use and Development Plan Update
Table 801-10a: Hawaii County General Plan Full Build-Out Water Demand Projection –
Hawi Aquifer System Area [80101]
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 6.5
Urban Expansion Domestic/Irrigation/Municipal 0.0
Resort Irrigation/Municipal 0.0
Industrial Industrial 0.2
Agriculture Agriculture 67.5
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 0.0
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 6.8
TOTAL w/ Ag* 74.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 801-11a: County Zoning Full Build-Out Water Demand Projection – Hawi Aquifer
System Area [80101]
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 0.8
Resort Irrigation/Municipal 0.0
Commercial Municipal 0.1
Industrial Industrial 0.2
Agriculture Agriculture 66.6
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 1.1
TOTAL w/ Ag* 67.7
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
801 Kohala Aquifer Sector Area
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Table 801-10b: Hawaii County General Plan Full Build-Out Water Demand Projection –
Waimanu Aquifer System Area [80102]
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 0.7
Urban Expansion Domestic/Irrigation/Municipal 0.0
Resort Irrigation/Municipal 0.0
Industrial Industrial 0.0
Agriculture Agriculture 9.4
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 0.1
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 0.8
TOTAL w/ Ag* 10.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 801-11b: County Zoning Full Build-Out Water Demand Projection – Waimanu
Aquifer System Area [80102]
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 0.1
Resort Irrigation/Municipal 0.0
Commercial Municipal 0.0
Industrial Industrial 0.0
Agriculture Agriculture 9.3
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 0.1
TOTAL w/ Ag* 9.3
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
801 Kohala Aquifer Sector Area
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Table 801-10c: Hawaii County General Plan Full Build-Out Water Demand Projection –
Mahukona Aquifer System Area [80103]
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 21.2
Urban Expansion Domestic/Irrigation/Municipal 6.5
Resort Irrigation/Municipal 0.8
Industrial Industrial 1.1
Agriculture Agriculture 90.6
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 0.6
DHHL Irrigation/Municipal 2.4
TOTAL w/o Ag* 32.6
TOTAL w/ Ag* 123.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 801-11c: County Zoning Full Build-Out Water Demand Projection – Mahukona
Aquifer System Area [80103]
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 3.9
Resort Irrigation/Municipal 0.3
Commercial Municipal 0.7
Industrial Industrial 0.4
Agriculture Agriculture 89.7
DHHL Irrigation/Municipal 2.4
TOTAL w/o Ag* 7.7
TOTAL w/ Ag* 97.4
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
801.4.2.1 Refine Land Use Based Projection
801.4.2.1.1 State Water Projects Plan
The total projected demand to the year 2020 for 22 State Water Projects within the Kohala
ASEA is 3.70 mgd, using 1.79 mgd potable, 1.83 mgd nonpotable, and 0.08 mgd nonpotable
using potable. These demands may account for between 30 percent and 90 percent of the total
water demand in the sector area, depending on the actual agricultural water usage. The project
which will generate the most significant demand, with the exception of DHHL projects, which
are covered separately, is listed in Table 801-12. Projects with large demands greater than 1
mgd may require State funding to develop resources and infrastructure necessary to provide
water service.
801 Kohala Aquifer Sector Area
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Table 801-12: Future State Water Projects to Generate Significant Demands
Project Name
Primary Use
State
Department
2020 Demand
(mgd)
Waimea Irrigation System Nonpotable DOA 1.83
801.4.2.1.2 State Department of Hawaiian Home Lands
The DHHL owns several tracts of land within the Kohala ASEA.
The Kawaihae Tract is comprised of over 10,000 acres of a wide variety of terrain and climate
from the Kohala Coast to the Kohala Mountains. Existing usage of the land includes the 196-lot
Kawaihae Unit 1 residential subdivision, which is temporarily being served by the privately
owned Kohala Ranch water system; and the 90-acre Kaei Hana II industrial subdivision,
currently being served by the DWS Kawaihae-Lalamilo-Puako water system. The rest of the
land is used for cattle and horse grazing. The projected demand of 2.04 mgd of potable water
will be met either through development of new well sources through partnership with DWS or
acquiring a portion of Ouli-1 well production.
The Pauahi and Keoniki Tracts are located northwest of Waimea Village covering 600 and 230
acres, respectively. Upper Lalamilo is a 230-acre tract located on the south side of Kawaihae
Road. All three tracts fall within the service area of the DWS Waimea Water System. DWS has
estimated an allocation of 0.08 mgd of the 0.32 mgd required by the proposed developments;
therefore, DHHL would need to partner with DWS to develop additional sources for the
projected needs.
Two of the three Puukapu Tracts are situated within the Kohala ASEA. Puukapu 2 is located in
the general area above Puukapu Homesteads mauka of Mamalahoa Highway, and Puukapu 3 is
located in the hillside north of Waimea Village within the service area of the DWS Waimea WS.
The projected demand is 0.004 mgd.
The Upolu Point Lot is composed of 37 acres of several existing buildings currently serviced by
the DWS Hawi-Kokoiki Water System. The Waimanu Tract is a 200-acre tract on the eastern
side of the Kohala Mountains with no vehicular access and designated for Conservation use.
Currently there are no recommended actions for either tract regarding water supply resources or
infrastructure.
801.4.2.1.3 Agricultural Water Use and Development Plan
There is no information available in the AWUDP specific to activity within the Kohala ASEA to
further refine projections.
801 Kohala Aquifer Sector Area
Page 801-35
Hawaii County
Water Use and Development Plan Update
801.4.3 Water Use Unit Rates
Water use unit rates are based on the Water System Standards as discussed in Chapter 1, and
single family residential (Low Density Urban category of the General Plan and RS-7.5 and
greater or Single-Family Residential categories of one lot per 7,500 acres or larger of County
Zoning) consumption is 1,000 gallons per unit for South Kohala, and 400 gallons per unit for
North Kohala based on historical consumption data.
801.4.4 5-Year Incremental Water Demand Projection to the Year 2025
The following section presents 5-year incremental water demand projections to the year 2025 for
the Kohala ASEA and the Hawi, Waimanu, and Mahukona ASYAs separately. The projected
low, medium, and high growth rates are listed in Tables 801-13, 801-13a, 801-13b, and 801-13c
for the sector and system areas, respectively, and are graphed in Figures 809-8, 809-8a, and 801-
8b, and 801-8c. Potable and nonpotable water demands are also differentiated.
Figures 801-8, 801-8a, 801-8b, and 801-8c illustrate the magnitude of the sustainable yield, both
LUPAG and Zoning full build-out water use, and water use projection through the year 2025
focusing on Medium Growth Rate B, for the sector and system areas, respectively. Figures 801-
9, 801-9a, 801-9b, and 801-9c show the breakdown of water demand projections by CWRM
categories through the year 2025. Tables 801-14, 801-14a, 801-14b, and 801-14c summarize
these figures for the sector and system areas, respectively.
801.4.4.1 Kohala Aquifer Sector Area
Table 801-13: Water Demand Projection – Kohala Aquifer Sector Area
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 2.3 2.7 3.1 3.7 4.3 6.5 7.6 8.8 10.3 12.0
Potable 2.3 2.7 3.1 3.7 4.3 2.3 2.7 3.1 3.7 4.3
Nonpotable 0.0 0.0 0.0 0.0 0.0 4.2 4.9 5.7 6.6 7.8
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 2.3 2.7 3.2 3.7 4.3 6.5 7.6 8.9 10.5 12.3
Potable 2.3 2.7 3.2 3.7 4.3 2.3 2.7 3.2 3.7 4.3
Nonpotable 0.0 0.0 0.0 0.0 0.0 4.2 4.9 5.7 6.7 7.9
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 2.3 2.8 3.3 3.9 4.6 6.5 7.8 9.2 11.0 13.0
Potable 2.3 2.8 3.3 3.9 4.6 2.3 2.8 3.3 3.9 4.6
Nonpotable 0.0 0.0 0.0 0.0 0.0 4.2 5.0 5.9 7.1 8.4
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
801 Kohala Aquifer Sector Area
Page 801-36
Hawaii County
Water Use and Development Plan Update
Figure 801-8: Water Demand Projection Summary – Kohala Aquifer Sector Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 801-14: Medium Growth Rate B Water Demand Projection by Category – Kohala
Aquifer Sector Area
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 2.3 2.7 3.2 3.7 4.3
Total with Ag* 6.5 7.6 8.9 10.5 12.3
Domestic 0.1 0.1 0.2 0.2 0.2
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 0.0 0.0 0.0 0.0 0.0
Agriculture 4.2 4.9 5.7 6.7 7.9
Military 0.0 0.0 0.0 0.0 0.0
Municipal 2.2 2.6 3.0 3.5 4.1
Potable 2.3 2.7 3.2 3.7 4.3
Nonpotable w/o Ag* 0.0 0.0 0.0 0.0 0.0
Nonpotable w/ Ag* 4.2 4.9 5.7 6.7 7.9
DWS 1.5 1.8 2.1 2.5 2.9
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
2005 2010 2015 2020 2025
YearDemand (mgd)Nonpotable w/ Ag*
Potable
Total w/ Ag*
Total w/o Ag* Potable
Nonpotable w/o Ag*
LEGEND: Growth Rate A Growth Rate B Growth Rate C
801 Kohala Aquifer Sector Area
Page 801-37
Hawaii County
Water Use and Development Plan Update
Figure 801-9: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Kohala Aquifer Sector Area
0
50
100
150
200
250
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 154
LUPAG = 40–208
Zoning = 9–174
Legend*, **
801 Kohala Aquifer Sector Area
Page 801-38
Hawaii County
Water Use and Development Plan Update
Figure 801-10: Medium Growth Rate B Water Demand Projection by Category – Kohala
Aquifer Sector Area
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
Legend*, **
801 Kohala Aquifer Sector Area
Page 801-39
Hawaii County
Water Use and Development Plan Update
801.4.4.2 Hawi Aquifer System Area [80101]
Table 801-13a: Water Demand Projection – Hawi Aquifer System Area [80101]
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 0.5 0.6 0.7 0.9 1.1 2.2 2.6 3.1 3.7 4.4
Potable 0.5 0.6 0.7 0.9 1.1 0.5 0.6 0.7 0.9 1.1
Nonpotable 0.0 0.0 0.0 0.0 0.0 1.7 2.0 2.4 2.8 3.3
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 0.5 0.6 0.8 0.9 1.1 2.2 2.6 3.2 3.8 4.5
Potable 0.5 0.6 0.8 0.9 1.1 0.5 0.6 0.8 0.9 1.1
Nonpotable 0.0 0.0 0.0 0.0 0.0 1.7 2.0 2.4 2.9 3.4
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 0.5 0.6 0.8 0.9 1.1 2.2 2.7 3.3 3.9 4.7
Potable 0.5 0.6 0.8 0.9 1.1 0.5 0.6 0.8 0.9 1.1
Nonpotable 0.0 0.0 0.0 0.0 0.0 1.7 2.0 2.5 3.0 3.6
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
801 Kohala Aquifer Sector Area
Page 801-40
Hawaii County
Water Use and Development Plan Update
Figure 801-8a: Water Demand Projection Summary – Hawi Aquifer System Area
[80101]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 801-14a: Medium Growth Rate B Water Demand Projection by Category – Hawi
Aquifer System Area [80101]
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 0.5 0.6 0.8 0.9 1.1
Total with Ag* 2.2 2.6 3.2 3.8 4.5
Domestic 0.0 0.0 0.0 0.1 0.1
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 0.0 0.0 0.0 0.0 0.0
Agriculture 1.7 2.0 2.4 2.9 3.4
Military 0.0 0.0 0.0 0.0 0.0
Municipal 0.5 0.6 0.7 0.9 1.0
Potable 0.5 0.6 0.8 0.9 1.1
Nonpotable w/o Ag* 0.0 0.0 0.0 0.0 0.0
Nonpotable w/ Ag* 1.7 2.0 2.4 2.9 3.4
DWS 0.5 0.6 0.7 0.9 1.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
2005 2010 2015 2020 2025
YearDemand (mgd)Nonpotable w/o Ag*
Total w/ Ag*
Total w/o Ag* Potable
Potable
Nonpotable w/ Ag*
LEGEND Growth Rate A Growth Rate B Growth Rate C
801 Kohala Aquifer Sector Area
Page 801-41
Hawaii County
Water Use and Development Plan Update
Figure 801-9a: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Hawi Aquifer System Area [80101]
0
10
20
30
40
50
60
70
80
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
Zoning =1–68
LUPAG = 7–74
SY = 27
Legend*,**
Addendum No. 1, 2/3/2012
801 Kohala Aquifer Sector Area
Page 801-42
Hawaii County
Water Use and Development Plan Update
Figure 801-10a: Medium Growth Rate B Water Demand Projection by Category – Hawi
Aquifer System Area [80101]
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
Legend*,**
801 Kohala Aquifer Sector Area
Page 801-43
Hawaii County
Water Use and Development Plan Update
801.4.4.3 Waimanu Aquifer System Area [80102]
Table 801-13b: Water Demand Projection – Waimanu Aquifer System Area [80102]
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 0.1 0.1 0.1 0.1 0.2 0.3 0.4 0.4 0.5 0.5
Potable 0.1 0.1 0.1 0.1 0.2 0.1 0.1 0.1 0.1 0.2
Nonpotable 0.0 0.0 0.0 0.0 0.0 0.2 0.3 0.3 0.3 0.4
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 0.1 0.1 0.1 0.1 0.2 0.3 0.4 0.4 0.5 0.6
Potable 0.1 0.1 0.1 0.1 0.2 0.1 0.1 0.1 0.1 0.2
Nonpotable 0.0 0.0 0.0 0.0 0.0 0.2 0.3 0.3 0.4 0.4
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 0.1 0.1 0.1 0.1 0.2 0.3 0.4 0.4 0.5 0.6
Potable 0.1 0.1 0.1 0.1 0.2 0.1 0.1 0.1 0.1 0.2
Nonpotable 0.0 0.0 0.0 0.0 0.0 0.2 0.3 0.3 0.4 0.4
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
801 Kohala Aquifer Sector Area
Page 801-44
Hawaii County
Water Use and Development Plan Update
Figure 801-8b: Water Demand Projection Summary – Waimanu Aquifer System Area
[80102]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 801-14b: Medium Growth Rate B Water Demand Projection by Category –
Waimanu Aquifer System Area [80102]
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 0.1 0.1 0.1 0.1 0.2
Total with Ag* 0.3 0.4 0.4 0.5 0.6
Domestic 0.0 0.0 0.0 0.0 0.0
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 0.0 0.0 0.0 0.0 0.0
Agriculture 0.2 0.3 0.3 0.4 0.4
Military 0.0 0.0 0.0 0.0 0.0
Municipal 0.1 0.1 0.1 0.1 0.1
Potable 0.1 0.1 0.1 0.1 0.2
Nonpotable w/o Ag* 0.0 0.0 0.0 0.0 0.0
Nonpotable w/ Ag* 0.2 0.3 0.3 0.4 0.4
DWS 0.1 0.1 0.1 0.1 0.1
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
2005 2010 2015 2020 2025
YearDemand (mgd)Nonpotable w/o Ag*
Total w/o Ag* Potable
Potable
Nonpotable w/ Ag*
Total w/ Ag*
LEGEND Growth Rate A Growth Rate B Growth Rate C
801 Kohala Aquifer Sector Area
Page 801-45
Hawaii County
Water Use and Development Plan Update
Figure 801-9b: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Waimanu Aquifer System Area [80102]
0
20
40
60
80
100
120
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 110
LUPAG = 1–10Zoning = 0–9
Legend*,**
Addendum No. 1, 2/3/2012
801 Kohala Aquifer Sector Area
Page 801-46
Hawaii County
Water Use and Development Plan Update
Figure 801-10b: Medium Growth Rate B Water Demand Projection by Category –
Waimanu Aquifer System Area [80102]
0.0
0.1
0.2
0.3
0.4
0.5
0.6
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
Legend*,**
801 Kohala Aquifer Sector Area
Page 801-47
Hawaii County
Water Use and Development Plan Update
801.4.4.4 Mahukona Aquifer System Area [80103]
Table 801-13c: Water Demand Projection – Mahukona Aquifer System Area [80103]
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 1.7 2.0 2.3 2.6 3.0 3.9 4.6 5.3 6.1 7.1
Potable 1.7 2.0 2.3 2.6 3.0 1.7 2.0 2.3 2.6 3.0
Nonpotable 0.0 0.0 0.0 0.0 0.0 2.2 2.6 3.0 3.5 4.0
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 1.7 2.0 2.3 2.7 3.1 3.9 4.6 5.3 6.2 7.2
Potable 1.7 2.0 2.3 2.7 3.1 1.7 2.0 2.3 2.7 3.1
Nonpotable 0.0 0.0 0.0 0.0 0.0 2.2 2.6 3.0 3.5 4.1
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 1.7 2.0 2.4 2.8 3.3 3.9 4.7 5.5 6.5 7.6
Potable 1.7 2.0 2.4 2.8 3.3 1.7 2.0 2.4 2.8 3.3
Nonpotable 0.0 0.0 0.0 0.0 0.0 2.2 2.7 3.1 3.7 4.4
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 801-8c: Water Demand Projection Summary – Mahukona Aquifer System Area
[80103]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
2005 2010 2015 2020 2025
YearDemand (mgd)Potable
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
2005 2010 2015 2020 2025
YearDemand (mgd)Total w/ Ag*
Potable
Nonpotable w/ Ag*
LEGEND: Growth Rate A Growth Rate B Growth Rate C
Total w/o Ag*
Nonpotable w/o Ag*
801 Kohala Aquifer Sector Area
Page 801-48
Hawaii County
Water Use and Development Plan Update
Table 801-14c: Medium Growth Rate B Water Demand Projection by Category –
Mahukona Aquifer System Area [80103]
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 1.7 2.0 2.3 2.7 3.1
Total with Ag* 3.9 4.6 5.3 6.2 7.2
Domestic 0.1 0.1 0.1 0.1 0.1
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 0.0 0.0 0.0 0.0 0.0
Agriculture 2.2 2.6 3.0 3.5 4.1
Military 0.0 0.0 0.0 0.0 0.0
Municipal 1.6 1.9 2.2 2.6 3.0
Potable 1.7 2.0 2.3 2.7 3.1
Nonpotable w/o Ag* 0.0 0.0 0.0 0.0 0.0
Nonpotable w/ Ag* 2.2 2.6 3.0 3.5 4.1
DWS 0.9 1.1 1.3 1.5 1.7
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
801 Kohala Aquifer Sector Area
Page 801-49
Hawaii County
Water Use and Development Plan Update
Figure 801-9c: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Mahukona Aquifer System Area [80103]
0
20
40
60
80
100
120
140
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 17
LUPAG = 33–123
Zoning = 8–97
Legend*, **
801 Kohala Aquifer Sector Area
Page 801-50
Hawaii County
Water Use and Development Plan Update
Figure 801-10c: Medium Growth Rate B Water Demand Projection by Category –
Mahukona Aquifer System Area [80103]
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
801.4.5 DWS Historical Water Consumption Data Projections
DWS supplied water consumption was projected in 5-year increments to the year 2025 based on
DWS historical water system consumption data from 1970 to 2003, as shown on Figure 801-11.
Legend*, **
801 Kohala Aquifer Sector Area
Page 801-51
Hawaii County
Water Use and Development Plan Update
Figure 801-11: DWS Water Demand Projection – Kohala Aquifer Sector Area
Kohala Aquifer Sector Systems
0.0
0.5
1.0
1.5
2.0
2.5
3.0
1970 1980 1990 2000 2010 2020mgdHistorical Projected
Year 2005: 1.70 mgd
Year 2010: 1.84 mgd
Year 2015: 1.97 mgd
Year 2020: 2.11 mgd
Year 2025: 2.24 mgd
This graph combines data for the Hawi,
Halaula, Makapala-Niulii, and Waimea
water systems.
Historical data provided by RW Beck, Inc.
Projections based on historical DWS water consumption data differ greatly from projections
based on population growth rate, although the 2005 estimates are close. This is because the
projected future rate of increase of the population is much higher than that of the historical
demand. DWS may need to supply potable water equivalent to approximately 50 percent of the
total projected water supply for the Kohala ASEA.
801 Kohala Aquifer Sector Area
Page 801-52
Hawaii County
Water Use and Development Plan Update
801.5 RESOURCE AND FACILITY RECOMMENDATIONS
801.5.1 Water Source Adequacy
801.5.1.1 Full Build-Out
Excluding agricultural demands, full development to the maximum density of the County
General Plan and Zoning within the Kohala Aquifer Sector Area (ASEA) is sustainable, with
water demands requiring 26 and 6 percent of the 154 mgd sustainable yield (SY), respectively.
However, the water demands associated with maximum density full build-out LUPAG scenario
within the Mahukona Aquifer System Area (ASYA) will exceed the system area SY of 17 mgd.
The existing Zoning within the Mahukona ASYA will require approximately 45 percent of the
SY. If worst case agricultural demands are included, the LUPAG and Zoning scenarios for the
Kohala ASEA and both the Hawi and Mahukona ASYAs are not sustainable. Water demands
associated with all scenarios within the Waimanu ASYA are sustainable.
801.5.1.2 Twenty-Year Projection
Existing and 20-year projected water demands within the Kohala ASEA are less than 10 percent
of the sector area SY. Existing water demands within the Mahukona ASYA range between 10
and 23 percent of the system area SY, and 20-year projected demands range between 18 and 43
percent of the system area SY. Existing and 20-year projected demands within the Hawi and
Waimanu ASYAs are less than 20 percent and less than 1 percent of the system area sustainable
yields, respectively.
801.5.2 Source Development Requirements
801.5.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, are evaluated to meet projected water demands.
801.5.2.1.1 Conventional Water Resource Measures
801.5.2.1.1.1 Ground Water
Most of the sustainable yield of the Kohala ASEA is within the Waimanu ASYA. It has been
speculated that much of that estimate actually is carried by the Upper and Lower Hamakua Ditch
Systems; however, the 1990 WRPP indicates that undoubtedly a large quantity of groundwater is
developable. Unfortunately, of the three aquifer system areas in the Kohala ASEA, the land over
the Waimanu ASYA is the least accessible and therefore the most difficult area on which to
develop groundwater sources. Most of the high level groundwater is impounded in dikes.
Evidence of the high-level aquifer has been shown by development of high level wells in the
Kohala Forest Reserve and in areas north of Waimea by DWS. Indications are that continued
development of this resource is viable.
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The basal aquifer may also be developed as a potable source. On the leeward side, it may be
brackish within a few miles from the coast; therefore, new wells should be located as far inland
as feasibly possible. DWS has installed a deep well to replace the spring sources in the
Makapala Water System, and has wells planned in the Halaula and Kokoiki areas of the Hawi
Water System.
801.5.2.1.1.2 Surface Water
The Kohala ASEA has one of the most abundant supplies of surface water on the island. One of
the utility courses of action in the General Plan is to “Encourage efforts to improve the Kohala
Ditch System and its use for agricultural purposes.” Farmers generally grow what is feasible in
the area; therefore, it is anticipated that agricultural water use will follow the availability of
irrigation water. Increase in the amount and accessibility of nonpotable water would likely
promote additional usage.
The primary sources of the DWS Waimea Water System are stream diversions. Although large
volumes of storage are necessary to provide adequate supply during dry periods, the available
supply of surface water is plentiful. Infrastructure improvements, such as tapping other streams
above Waimea Village, are an option; however, usage of surface water to supply potable water
requires strict adherence to DOH regulations including treatment and monitoring.
A significant challenge with developing surface water for either potable or nonpotable uses is
transmission. The four major ditch systems on the island originate and obtain sources from the
Kohala ASEA; systems to supply nonpotable source water are already in place but are in need of
repair. The AWUDP includes the study of and proposal of a capital improvement program to
reinstate the Lower Hamakua Ditch, and the Waimea Irrigation System, which is supplied by the
Upper Hamakua Ditch. As previously stated in Chapter 1, the impacts of the October 15, 2006
earthquake are not fully understood; therefore, the extent to which the ditch systems can feasibly
be utilized is not known.
801.5.2.1.1.3 Water Transfer
Some of the source water that is produced in the Kohala ASEA is currently being transferred to
other sectors. Surface water sources originating in the Kohala ASEA supply the DWS Waimea
WS; however, part of the system south of Mamalahoa Highway is located in the West Mauna
Kea Sector. Additionally, there is an unvalved, unmetered connection between DWS’s Waimea
and Haina Water Systems in the vicinity of the Waimea Country Club. The exact amount that is
being transferred is not known.
Transfer of water to the West Mauna Kea ASEA (803) and potentially the Northwest Mauna Loa
ASEA (807) is expected to increase due to limited supply of groundwater in those sectors, and
anticipated growth of the three major resort complexes along the coast. It has been proposed to
construct a large transmission pipeline to transfer at least 20 mgd from the Hawi area to the
Lalamilo Water System. This is one of many alternatives to facilitate the transfer of potable
water. Another alternative might be to develop high-level groundwater in the Waimea area,
801 Kohala Aquifer Sector Area
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which could be transferred via the Waimea WS to the Lalamilo WS. Infrastructure
improvements would likely be required, such as larger mains, pressure reducing valves, and
storage tanks. The high elevation of Waimea would allow most of the water to flow by gravity,
thereby reducing pumping costs.
Potable water also will eventually need to be transferred from the Waimanu ASYA to the
Mahukona ASYA in order to sustain the full build-out demands associated with the General
Plan. Growth trends indicate that this would be in the distant future, but should be considered.
801.5.2.1.2 Alternative Water Resource Enhancement Measures
801.5.2.1.2.1 Rainwater Catchment Systems
Rainwater catchment systems are a viable option in areas that receive abundant rainfall, which
includes the entire sector area except from the leeward coast to about halfway up the slopes of
the Kohala Mountain. Catchment systems are a suitable source of potable water for individual
domestic users in areas outside the limits of municipal water systems, and may continue to be if
implementing a municipal system is not feasible. Generally, these areas are remote and are not
expected to expand significantly, because most development will be concentrated within existing
urban areas. Therefore, usage of this source likely will not increase.
801.5.2.1.2.2 Wastewater Reclamation
Wastewater reclamation is a possible resource enhancement measure, but would be limited to
uses within the immediate vicinity of the treatment facility. The quantity of wastewater available
for reclamation is also dependent on the amount of potable water used. Indications are that the
potential quantity of reclaimed wastewater would be insignificant compared to the magnitude
and availability of other sources of nonpotable water.
801.5.2.1.2.3 Desalination
Desalination of brackish groundwater is a potential alternative, but due to the high cost, likely
would not be used if other sources of potable water are available. The most favorable location
meeting these criteria is along the leeward coast, remote from the municipal water systems, and
where groundwater is brackish. Currently, these areas are classified as “Agricultural” under both
LUPAG and Zoning, and a significant quantity of potable water may not be required.
801.5.2.2 Demand-Side Management
801.5.2.2.1 Development Density Control
The full build-out demand associated with LUPAG is nearly five times that of Zoning, due to the
greater urban area proposed under LUPAG, and due to the difference in urban unit density rates.
In particular, Urban Expansion areas comprise one-third of the LUPAG Urban area. There is
greater flexibility to control the densities of these areas because they are currently undesignated.
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County Planning may consider re-examining proposed urban areas because the full build-out
demands in the Mahukona ASYA cannot be met by the sustainable yield.
801.5.2.2.2 Water Conservation
The average water consumption of all accounts on the DWS system is approximately 550 gpd
per connection, which is slightly higher than the island average. Additionally, the estimated
potable water usage per capita from all sources is approximately 180 gpd.
The concept of water conservation should be stressed everywhere, but focused on the Mahukona
ASYA. Potential demand side-conservation measures include voluntary water reduction,
efficient landscaping infrastructure and practices, and public education.
The DWS Hawi and Makapala Water Systems average less than 15 percent of unaccounted
water. Because of the small quantity produced, this is not considered critical.
801.5.3 Recommended Alternatives
Development of high-level groundwater sources should continue to be the primary source of
potable water, with close monitoring of water levels. Although the cost of drilling and pumping
is expensive, cost savings may be achieved in the transmission process by allowing water to flow
by gravity to lower elevation areas. Basal water sources may be developed to supply localized
areas in the vicinity of Hawi.
Feasibility and cost studies should be initiated to assess the potential to increase development of
surface water for potable water use, if groundwater sources become stressed. Surface water
should continue to be the primary source of nonpotable water. Restoration of the four major
ditch systems should be investigated and planned to meet anticipated future irrigation and
agricultural needs. It is anticipated that the next update to the AWUDP will address these issues
in greater detail.
Due to the availability and abundance of water sources in the Kohala ASEA, potable water
should be developed for the purpose of transfer out of the Sector to the West Mauna Kea (803)
and Northwest Mauna Loa (807) ASEAs, and also within the Sector from the Waimanu ASYA
to the Mahukona ASYA, where shortfalls of potable water supply may arise. A detailed water
balance should be established for the Kohala ASEA; quantities of water transferred into and out
of the sector should be monitored, which would necessitate the installation of meters on all
watermains that cross into other aquifer sector areas. Several alternatives, such as those
described previously, should be examined to determine the most financially and sociably
acceptable method of accomplishing this task.
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802 EAST MAUNA KEA AQUIFER SECTOR AREA
802.1 SECTOR AREA PROFILE
802.1.1 General
The East Mauna Kea Aquifer Sector Area (ASEA) includes the Honokaa, [80201] Paauilo
[80202], Hakalau [80203], and the Onomea [80204] Aquifer System Areas (ASYA), and spans
three districts, capturing most of the northern section of the Hamakua district, and the northern
sections of the North Hilo and South Hilo districts. The sector includes the northern and eastern
slopes of Mauna Kea and most of the northeastern coast of the island from Waipio Bay to Hilo
Bay.
Rainfall is extremely variable throughout the sector area. Rainfall in the coastal areas average
less than 100 inches and up to 150 inches per year, which increases to 300 inches per year in a
lateral band in the 2,000 to 4,000 foot elevation range 5 miles inland of Hilo. The summits of
Mauna Kea experience less than 20 inches per year. The Hakalau ASYA has the highest
sustainable yield of the four system areas at 150 mgd, followed by the Onomea ASYA at 147
mgd, the Paauilo ASYA at 60 mgd, and the Honokaa ASYA at 31 mgd. The total sustainable
yield of the East Mauna Kea ASYA is 388 mgd.
802.1.2 Economy and Population
802.1.2.1 Economy
Agriculture continues to be the primary source of income and employment within the sector area.
The demise of the sugar industry has made lands available for various other crops, including
macadamia nuts, eucalyptus trees, flowers, fruits and vegetables. Large tracts of land are also
used for cattle grazing and logging of native and planted forests. A new 15,000-acre eucalyptus
plantation has created 100 full-time jobs in the sector. State DLNR has partnered with Hawaii
Forestry and Communities Initiative to cultivate 40 acres of State land in Ookala with high value
hardwoods. The project will be managed by several local groups with assistance from State and
Federal agencies.
Visitor accommodations are limited to scattered private bed-and-breakfast operations, with the
exception of a 19-unit hotel in Honokaa.
The Hamakua Energy Partners’ new 60-MW co-generation power plant in Haina is the largest
generating facility on the island, and is anticipated to attract other manufacturing operations that
use thermal energy.
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802.1.2.2 Population
Over half of the population contributing to the demands from the East Mauna Kea ASEA is
within the South Hilo District, and over one third is within the Hamakua District. Population
centers are scattered and are generally tied to former plantation areas, and the marginal growth
over the past 20 years can be attributed to the activities in other sector areas. Scattered
homesteads and ranches are located at higher elevations.
Table 802-1: Historical Population
1980 1990 2000
1980-90
% Change
1990-2000
% Change
13,680 14,997 16,745 9.6 11.7
Data Source: 2000 U.S. Census
Data redistributed and evaluated for East Mauna Kea Aquifer Sector Area
Table 802-2: Population Projection
Growth
Rate 2000 2005 2010 2015 2020
2000-10
% Change
2010-20
% Change
A – Low 16,745 16,920 17,814 18,745 19,779 6.4 11.0
B – Medium 16,745 16,974 17,971 19,022 20,175 7.3 12.3
C – High 16,745 17,682 19,098 20,515 21,991 14.1 15.1
Data Source: County General Plan, February 2005
Data redistributed and evaluated for East Mauna Kea Aquifer Sector Area
802.1.3 Land Use
802.1.3.1 Hawaii County General Plan
The Hawaii County General Plan Land Use Pattern Allocation Guide Map for the East Mauna
Kea ASEA is shown on Figure 802-1. The estimated land use allocation acreage for each
LUPAG designation within the sector area is listed in Table 802-3.
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Table 802-3: LUPAG Map Estimated Land Use Allocation Acreage East Mauna Kea Aquifer
Sector Area
LAND USE PATTERN ACREAGE
% of
TOTAL
High Density Urban 0 0
Medium Density Urban 507 0.1
Low Density Urban 5,634 1.5
Industrial 241 0.1
Important Agricultural Land 121,310 31.4
Extensive Agriculture 103,668 26.8
Orchard 0 0
Rural 380 0.1
Resort/Resort Node 6 0.0
Open 1,738 0.5
Conservation 152,856 39.6
Urban Expansion 65 0.0
University Use 0 0
TOTAL 386,405 100.0
The water utility courses of action for Hamakua, and North Hilo, and South Hilo in the Hawaii
County General Plan relevant to the East Mauna Kea ASEA are as follows:
(a) Continue to co-ordinate programs with State and Federal Agencies to develop a well at
Kukuihaele and Honakaa Hospital to the standards of the DWS.
(b) Investigate groundwater sources in the Honokaa and Kukuihaele areas.
(c) Develop a stand-by well for the Ookala system.
(d) Replace old, sub-standard, or deteriorating lines and storage facilities.
(e) Investigate groundwater sources at Kaieie Mauka, Kulaimano, Saddle Road and Honomu
areas.
(f) Further investigate future ground water resources.
802.1.3.2 Hawaii County Zoning
Hawaii County Zoning for the East Mauna Kea ASEA is shown on Figure 802-2. The estimated
land use allocation acreage for each zoning class within the sector area is listed in Table 802-4.
802 East Mauna Kea Aquifer Sector Area
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Table 802-4: County Zoning Estimated Class Allocation Acreage – East Mauna Kea
Aquifer Sector Area
ZONING CLASS ACREAGE
% of
TOTAL
Single Family Residential 1,926 0.5
Multi-Family Residential
(including duplex) 41 0.0
Residential-Commercial Mixed Use 0 0
Resort 40 0.0
Commercial 71 0.0
Industrial 132 0.1
Industrial-Commercial Mixed 0 0
Family Agriculture 6 0.0
Residential Agriculture 92 0.0
Agriculture 239,937 62.1
Open 1,270 0.3
Project District 0 0
Forest Reserve 140,305 36.3
(road) 2,584 0.7
TOTAL 386,404 100.0
802.2 EXISTING WATER RESOURCES
802.2.1 Ground Water
East Mauna Kea ASEA has a sustainable yield of 388 mgd. According to the CWRM database,
there are 26 production wells in the sector, including 9 municipal, 5 domestic, 4 irrigation, 7
industrial, and 1 other. There are also 33 wells drilled and categorized as “unused”. Refer to
Appendix B for this database. Figure 802-3 shows the well locations.
802.2.2 Surface Water
More perennial streams are located in the East Mauna Kea ASEA than on the rest of the island.
Of the 85 perennial streams classified in the HSA, 60 are continuous, and the other 25 are
intermittent. One gage operated by the USGS is located on the Honolii Stream near Papaikou.
Records from the gage were listed previously in Table 1-8.
There are 62 declared stream diversions in CRWM database shown on Figure 802-4, which
accounts for 30 percent of the 202 declared stream diversions on the island. The stream
diversions with declared flows are listed in Table 802-5.
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Figure 802-3: Well and Tunnel Location
MAP CURRENTLY NOT AVAILABLE ON-LINE
802 East Mauna Kea Aquifer Sector Area
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Figure 802-4: Streams & Diversions
MAP CURRENTLY NOT AVAILABLE ON-LINE
802 East Mauna Kea Aquifer Sector Area
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Table 802-5: Stream Diversions – East Mauna Kea Aquifer Sector Area
FILE REFERENCE TMK STREAM NAME
HAWAII DWS 2-8-003:002 Unnamed Spring Spring diversion, pipe from Maukaloa (Makea). Declared Q =
0.190 MGD.
HAWAII DWS 2-8-010:033 Unnamed/ Unmapped
Spring
Spring diversion, pipe from Akaka Falls Spring. Declared Q =
0.09 MGD.
2-8-011:005 Honomu
Stream diversion, intake from Malamalama Iki Stream (new
entry). SCAP-HA-317 After-the-Fact Permit approved for
intake. Water used to wash down farm equipment. Maximum
Q = 100 gpd.
3-1-003:002 Peleau
Stream diversion, intake from Peleau. (new entry). SCAP-
HA-314 After-the-Fact Permit approved for intake with
maximum Q = 8 gpm.
HAWAII DWS 3-2-002:041 Unnamed/ Unmapped
Spring
Spring diversion, 2 pumps from Chaves Spring. Declared Q
= 0.02 MGD.
GILLMAR JNS 3-3-001:005 Nanue Stream diversion, dam on Nanaue Stream. Declared Q of 1
cubic foot per second; estimated from flow rate.
HAWAII DWS 3-5-004:035 Unnamed/ Unmapped
Spring
Spring diversion, pipe from Kihalani Spring. Declared Q =
0.01 MGD.
HAWAII DWS 3-5-004:050 Unnamed/ Unmapped
Spring
Spring diversion, pipe from Manowaiopae Spring. Declared
Q = 0.05 MGD.
3-6-006:018 Manowaiopae
Stream diversion, upper dam and pipe on Manowaiopae
Stream. Declared Q = 100 gpm; Verified Q = 48 gpm. SCAP-
HA-195 for After-the-Fact permit approved for this diversion.
3-6-006:018 Manowaiopae
Stream diversion, lower dam and pipe on Manowaiopae
Stream (new entry). Declared Q = 100 gpm; Verified Q = 66
gpm. Application for After-the-Fact Permit was denied for
this diversion in SCAP-HA-195.
HAWAII DWS 2-7-005:030 Unnamed/ Unmapped
Spring
Spring diversion, pipe from Kaieie Spring. Declared Q =
0.030 MGD.
802.2.3 Reclaimed Wastewater
There are no wastewater reclamation facilities within the sector area.
802.3 EXISTING WATER USE
802.3.1 General
The total estimated average water use within the East Mauna Kea ASEA from November 2004
through October 2005 based on DWS meter data and CWRM pumpage data and available GIS
data is listed in Table 802-6 and summarized in Figure 802-5, in accordance with CWRM
categories; and indicate the quantities supplied excluding agricultural demands, and the
quantities supplied including worst case agricultural demands (as described in Chapter 2) by the
DWS system and non-DWS systems.
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Table 802-6: Existing Water Use by Categories – East Mauna Kea Aquifer Sector Area
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.29 10.3 2.4
Industrial 0.90 31.7 7.3
Irrigation 0.03 1.1 0.2
Reclaimed WW 0.00 0.0 0.0
Agriculture 9.56 0.0 77.1
Military 0.00 0.0 0.0
Municipal
DWS System 1.62 57.0 13.0
Private Public WS 0.00 0.0 0.0
Total without Ag 2.84 100.0
Total with Ag 12.40 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 802-5: Existing Water Use by Categories – East Mauna Kea Aquifer Sector Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 802-6 generally shows the service areas for the various water systems and indicates the
extent of the DWS water system.
Domestic 10.3%
Industrial 31.7%
Irrigation 1.1%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 0.0%
Municipal
(DWS) 57.0%
Domestic 2.4%
Industrial 7.3%
Irrigation 0.2%
Irrigation (Recl'd
WW) 0.0%
Agriculture 77.1%
Military 0.0%
Municipal
(Non-DWS) 0.0%
Municipal
(DWS) 13.0%
w/o Agricultural Water Use* with Agricultural Water Use*
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802.3.2 Domestic Use
Domestic use or water use by individual households is assumed to be supplied by private
individual rainwater catchment systems. Based on available GIS data, there are 730 such units
or approximately 2,000 people, which is 12 percent of the sector’s population. The estimated
demand is 0.29 mgd. The 5 wells in the CWRM database classified as “Domestic” have not
reported pumpage.
802.3.3 Industrial Use
Hamakua Energy owns two wells for use at the Haina power plant, with a reported pumpage of
0.9 mgd.
802.3.4 Irrigation Use
There are two golf courses within the East Mauna Kea ASEA. The Waimea Country Club is
located west of Waimea Village along Mamahaloa Highway. One well classified as “Irrigation”
located in the vicinity is owned by Otaka Inc. The reported pumpage is 0.03 mgd. It is not
known if the Hamakua Country Club located outside of Honokaa uses irrigation. There is no
reported irrigation usage dedicated to other landscaping activities.
802.3.5 Agricultural Use
The Lower Hamakua Ditch originally was built to service the Hamakua Sugar Company’s
plantation, but was taken over by the HDOA after the closure of the company in 1993. The
system consists of five scattered reservoirs and 14 miles of ditch generally parallel to Hawaii
Belt Road from the Kukuihaele Weir to the Paauilo Reservoir. According to the AWUDP, the
plantation installed service laterals along the length of the ditch, most of which consist entirely of
buried pipelines, and are in the process of being located by the HDOA. The system is not fully
metered, although a USGS gage located 500 feet upstream of the Kukuihaele Weir recorded an
average flow of 6.5 mgd in 2003. Since the closure of the sugar company, only limited farming
has taken place along the ditch system.
802.3.6 Military Use
There is no military use in the East Mauna Kea ASEA.
802.3.7 Municipal Use
Municipal use can be subcategorized into the other water use categories, namely Domestic,
Industrial, Irrigation, Agriculture, and Military, if detailed information is available.
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802.3.7.1 County Water Systems
The DWS has 10 systems in the East Mauna Kea ASEA.
The Haina Water System uses a combination of surface and groundwater sources for its supply.
The surface water supply comes from the Waimea Water Treatment Plant via the Waimea Water
System which crosses into Hamakua from South Kohala via two unmetered connections.
Groundwater is supplied from the Haina Deep Well near Honokaa Town. The system is
widespread, serving the towns of Honokaa and Haina and extending to the scattered mauka
communities, which necessitates 24 storage tanks and 10 booster pump stations.
The Paauilo Water System is a small system serving two zones in the Paauilo area. A single well
and two storage tanks serve the system; however, a one-way, normally closed connection is
available to receive supply from the Haina Water System if necessary.
The Kukuihaele Water System serves the communities of Kukuihaele and Kapulena and relies
on Kukuihaele (Waiulili) Spring for its supply. Two operational zones are served by two booster
pump stations and two storage tanks.
The Ookala Water System is a small former plantation system that provides domestic water
service to Ookala Village. The supply was once purchased from the Hamakua Sugar Co., but is
now obtained from Ookala Well. Storage is achieved through a single concrete tank.
The Laupahoehoe Water System serves the Laupahoehoe community and surrounding areas,
extending west to Waipunalei and east to Kapehu. Like many systems along the Hamakua
Coast, supply was once obtained from high level springs, namely, the Manowaiopae Spring and
the Kihalani Spring (Kuwaikahi Gulch). These springs were not dependable during dry weather
periods; therefore, with the installation of two deep wells in Laupahoehoe, the spring sources
were eventually phased out of service. A single booster pump station, three storage tanks and a
series of pressure reducing valves (PRV) provide service to the six operational zones.
The Ninole Water System is a small system completed in 1977, some of whose services were
formerly plantation housing. The system obtains its supply from Chaves Spring. One booster
pump station pumps treated water from the spring to the distribution system and storage tank.
The Hakalau Water System serves a former plantation community with water from a
combination of the Hakalau Well and the Hakalau Iki Spring. Storage is provided by two tanks
in series downstream of the spring source.
The Honomu Water System has a relatively reliable supply from the Akaka Falls Spring. The
system has one storage tank.
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The Pepeeko Water System obtains its water from the Maukaloa Spring, which is a relatively
reliable source, and the Kulaimano Deep Well to supplement the spring when needed. Two
tanks provide storage for the system.
The Paukaa-Papaikou Water System serves the Papaikou and surrounding communities north to
Kalaoa Camp and south to Paukaa. The system is supplied by two spring sources, the Kaieie
Mauka (Papaikou) and Kaieie Medeiros Springs, and one well source. DWS is currently
developing a well source to replace the unreliable Kaieie Mauka Spring, which often runs dry.
Four storage tanks and two booster pump stations provide service to eight operational zones.
There is also a 6-inch main connecting the Paukaa-Papaikou Water System to the adjacent Hilo
Water System. A normally closed valve allows water to flow in both directions if needed.
DWS water use is subcategorized in Table 802-7, to the extent possible, based on available
meter data, and is depicted in Figure 802-7. “Other Municipal” includes facilities such as
schools, and various commercial, government, medical and nonprofit entities which have mixed
water use and cannot be specifically allocated to the other categories.
Table 802-7: DWS Existing Water Use by Categories – East Mauna Kea Aquifer Sector
Area
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 1.33 82.3
Industrial 0.00 0.0
Irrigation 0.00 0.0
Agriculture 0.10 6.2
Military 0.00 0.0
Other Municipal 0.19 11.5
Total 1.62 100.0
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Figure 802-7: DWS Existing Water Use by Categories – East Mauna Kea Aquifer Sector
Area
Domestic 82.3%
Industrial 0.0%
Irrigation 0.0%
Agriculture 6.2%
Military 0.0%
Other Municipal
11.5%
802.3.7.2 State Water Systems
There are no State water systems in the East Mauna Kea ASEA regulated by the DOH.
802.3.7.3 Federal Water Systems
There are no Federal water systems in the East Mauna Kea ASEA regulated by the DOH.
802.3.7.4 Private Public Water Systems
There are no private public water systems within the East Mauna Kea ASEA regulated by the
Department of Health.
802.3.8 Water Use by Resource
802.3.8.1 Ground Water
Table 802-8 summarizes the current production, potential production (16 and 24-hour
operation), sustainable yield (SY), and percentage of SY for the various productions calculated.
Current production is represented by the highest 12-month moving average (MAV) or the
802 East Mauna Kea Aquifer Sector Area
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highest annual average yield calculated from the actual pumpage data. Potential well production
is based on installed pump capacities, and calculated for both 16 hours of operation a day and 24
hours of operation a day. Data is based on pumpage data reported to CWRM.
Table 802-8: Sustainable Yield – East Mauna Kea Aquifer Sector Area
Sys Code System Area
High
12-Month
MAV
(MGD)
Potential
16 -Hour
Production
(MGD)
Potential
24-Hour
Production
(MGD) SY (MGD)
High
12-Month
MAV SY
(%)
Potential
16-Hour
Production SY
(%)
Potential
24-Hour
Production SY
(%)
2.06 23.86 35.79 388 0.53 6.15 9.22
80201 Honokaa 1.41 2.31 3.46 31 4.55 7.44 11.16
80202 Paauilo 0.14 4.51 6.77 60 0.23 7.52 11.28
80203 Hakalau 0.13 16.17 24.25 150 0.09 10.78 16.17
80204 Onomea 0.38 0.87 1.31 147 0.26 0.59 0.89
Seven spring sources are utilized in six of DWS’s water systems in the East Mauna Kea ASEA.
Two additional spring sources currently are not in use. Spring sources are not included in the
CWRM well database; therefore, are not reflected in Table 802-8. Table 802-9 lists the quantity
of water obtained from each source between November 2004 and October 2005, and the
estimated capacities according to the 2006 DWS 20-Year Water Master Plan.
Table 802-9: Spring Sources – East Mauna Kea Aquifer Sector Area
Source Name DWS Water System
Estimated
Capacity
(mgd)
Water Use
(mgd)
Kukuihaele Spring Kukuihaele 0.144 0.03
Chaves Spring Ninole 0.06 0.02
Hakalau Iki Spring Hakalau 0.046 0.08
Akaka Falls Spring Honomu 0.14 0.05
Maukaloa Spring Pepeeko 0.4 0.00
Kaieie Mauka (Papaikou)
Spring Paukaa-Papaikou 0.03 0.01
Kaieie Medeiros Spring Paukaa-Papaikou 0.02 0.06
Kihalani Spring Laupahoehoe 0.1 N/A
Manowaiopae Laupahoehoe 0.02 N/A
802.3.8.2 Surface Water
Surface water consumption within the sector area includes agricultural users of the Lower
Hamakua Ditch. Actual consumption is not readily available.
802 East Mauna Kea Aquifer Sector Area
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802.3.8.3 Rainwater Catchment
Water consumption calculated for developed parcels that are not supplied by groundwater or
surface water is assumed to be supplied by rainwater catchment. The water use previously
categorized as Domestic Use in Table 802-6 is assumed to be supplied by individual catchment
systems. As stated earlier, there is no reported pumpage for domestic wells.
802.3.8.4 Reclaimed Wastewater
There are no wastewater reclamation facilities in the East Mauna Kea ASEA.
802.4 FUTURE WATER NEEDS
802.4.1 General
Table 802-10 summarizes the LUPAG, Zoning and 5-year incremental water demand projection
scenarios for the total aquifer sector area and the individual aquifer system areas. The
sustainable yield (SY) is presented to draw comparisons.
Table 802-10: Summary of Demand Projections
Growth Rate B Demand Projections (mgd)Without
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total E. Mauna Kea ASEA 388 25.4 8.2 2.8 3.0 3.3 3.5 3.8
80201 – Honokaa ASYA 31 9.5 2.1 1.6 1.8 2.0 2.2 2.4
80202 – Paauilo ASYA 60 2.5 0.5 0.3 0.4 0.4 0.4 0.4
80203 – Hakalau ASYA 150 5.2 2.5 0.3 0.3 0.3 0.3 0.3
80204 – Onomea ASYA 147 8.3 3.0 0.6 0.6 0.6 0.6 0.7
Growth Rate B Demand Projections (mgd)With
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total E. Mauna Kea ASEA 388 405.5 378.1 12.4 13.2 14.0 14.8 15.8
80201 – Honokaa ASYA 31 105.2 92.6 4.0 4.4 4.9 5.3 5.9
80202 – Paauilo ASYA 60 135.6 131.8 3.7 3.9 4.1 4.4 4.6
80203 – Hakalau ASYA 150 98.0 93.1 2.6 2.7 2.8 2.9 3.0
80204 – Onomea ASYA 147 66.6 60.7 2.1 2.1 2.2 2.2 2.3
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
For all aquifer system areas, full build-out water demands excluding agricultural demands are
considerably less than the SY, and the 2025 demand projection excluding agricultural demand is
less than one-tenth the SY. Therefore, analysis of the three demand scenarios does not need to
be broken down by aquifer system areas and thus will be presented for the aquifer sector area
only.
802 East Mauna Kea Aquifer Sector Area
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802.4.2 Full Build-Out Water Demand Projections
The full build-out water demand projections based on the General Plan and County Zoning for
the East Mauna Kea ASEA are listed in Tables 802-11 and 802-12, and reflect refinement as
discussed below. Each land use class is associated with the most appropriate CWRM water use
category.
Table 802-11 Hawaii County General Plan Full Build-Out Water Demand Projection –
East Mauna Kea Aquifer Sector Area
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 20.6
Urban Expansion Domestic/Irrigation/Municipal 0.2
Resort Irrigation/Municipal 0.1
Industrial Industrial 1.0
Agriculture Agriculture 380.1
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 0.2
DHHL Irrigation/Municipal 3.4
TOTAL w/o Ag* 25.4
TOTAL w/ Ag* 405.5
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 802-12: Zoning Full Build-Out Water Demand Projection – East Mauna Kea Aquifer
Sector Area
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 3.9
Resort Irrigation/Municipal 0.2
Commercial Municipal 0.2
Industrial Industrial 0.5
Agriculture Agriculture 370.0
DHHL Irrigation/Municipal 3.4
TOTAL w/o Ag* 8.2
TOTAL w/ Ag* 378.1
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
802.4.2.1 Refine Land Use Based Projection
802.4.2.1.1 State Water Projects Plan
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The total projected demand to the year 2020 for 11 State Water Projects within the East Mauna
Kea ASEA is 0.02 mgd, all requiring potable sources. The project requiring the largest portion
of the total demand is the Honokaa Elementary New 4 Classroom project, by the Department of
Education, at 0.0072 mgd.
802.4.2.1.2 State Department of Hawaiian Home Lands
Seven tracts of land are controlled by the DHHL within the East Mauna Kea ASEA, the most on
the island.
The Kamoku-Kapulena tract is a u-shaped 3,529-acre tract located northeast of Waimea Village
cut by Hawaii Belt and Mamalahoa Highways. The Waikoloa-Waialeale tract lies within the u-
part of the Kamoku-Kapulena tract and is 1,206 acres in area. The Nienie tract is further east of
the Kamoku-Kapulena tract mauka of Mamalahoa Highway and is 7,135 acres in area. Average
rainfall values range between 30 and 75 inches per year. Currently, DHHL has not proposed
water demand for the three tracts.
The Honokaia tract lies in on the west side of the Nienie tract. Ground elevations vary between
2,220 feet at the makai end to 3,440 feet at the mauka end. The 3,243 acres of land are proposed
primarily for agricultural use, but also for residential and commercial use. Water demand is
estimated to be 1.16 mgd.
The Lower Piiohuna tract is bordered by forest reserve northwest of Hilo. The 1,842 acres were
formerly used for sugar cane, but are currently uncultivated. Numerous streams traverse the
tract, and there is plenty of rainfall, averaging between 170 and 250 inches per year. Potential
water supplies are the DWS Hilo Water System, and Wailuku River or other streams and springs
for irrigation water. The proposed land uses of the tract are agricultural and residential with an
estimated demand of 0.89 mgd.
The Honomu and Kuhua tracts combined are 766 acres of former sugar cane land located above
Honomu Village on the coast above Hilo. Average annual rainfall ranges between 150 and 250
inches. The tracts may be serviced by the DWS Honomu Water System; however, the estimated
demand of 1.14 mgd far exceeds the capacity of the water system. There are several spring
sources in the vicinity; however, their potential as sources of irrigation water has not yet been
determined.
The Humuula tract is a 49,100-acre tract of land along the eastern slope of Mauna Kea. Average
rainfall varies with elevation in the tract, ranging from 40 inches along the upper boundary to
112 inches along the lower boundary. The Upper Piiohuna tract is a 7,078-acre tract on the east
side of the Humuula tract. Because there is no potable water system or perennial stream in
feasible proximity, the DHHL Special Report #2 has recommended that individual roof
catchment and storage systems be installed for each unit as developed. The proposed demand is
0.16 mgd.
802 East Mauna Kea Aquifer Sector Area
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802.4.2.1.3 Agricultural Water Use and Development Plan
The AWUDP estimates the potential service area of the Lower Hamakua Ditch System to be
4,765 acres, with a 20-year service area of between 1,070 and 6,240 acres. The AWUDP
estimates that the average agricultural irrigation water unit rate is 3,400 gallons per acre per day,
which translates to a 20-year water requirement of between 3.64 and 21.22 mgd. Because of the
uncertainty of the projected service area, the associated water demands were not used to refine
the full build-out projections.
802.4.3 Water Use Unit Rates
Water use unit rates are based on the Water System Standards as discussed in Chapter 1.
802.4.4 5-Year Incremental Water Demand Projection to the Year 2025
The following section presents 5-year incremental water demand projections to the year 2025 for
the East Mauna Kea ASEA. The projected low, medium, and high growth rates are listed in
Table 802-13, and are graphed in Figure 802-8. Potable and nonpotable water demands are also
differentiated.
Figure 802-9 illustrates the magnitude of the sustainable yield, both LUPAG and Zoning full
build-out water use, and water use projection through the year 2025 focusing on Medium Growth
Rate B. Figure 802-10 shows the breakdown of water demand projections by CWRM categories
through the year 2025. Table 802-14 summarizes these figures.
Table 802-13: Water Demand Projection – East Mauna Kea Aquifer Sector Area
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 2.8 3.0 3.2 3.5 3.7 12.4 13.1 13.8 14.6 15.4
Potable 1.9 2.0 2.1 2.2 2.4 1.9 2.0 2.1 2.2 2.4
Nonpotable 0.9 1.0 1.1 1.2 1.3 10.5 11.1 11.7 12.4 13.1
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 2.8 3.0 3.3 3.5 3.8 12.4 13.2 14.0 14.8 15.8
Potable 1.9 2.0 2.1 2.3 2.4 1.9 2.0 2.1 2.3 2.4
Nonpotable 0.9 1.0 1.1 1.2 1.4 10.5 11.1 11.8 12.6 13.4
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 2.8 3.1 3.4 3.7 4.0 12.4 13.4 14.5 15.5 16.7
Potable 1.9 2.1 2.2 2.4 2.6 1.9 2.1 2.2 2.4 2.6
Nonpotable 0.9 1.0 1.2 1.3 1.4 10.5 11.4 12.2 13.1 14.1
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
802 East Mauna Kea Aquifer Sector Area
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Water Use and Development Plan Update
Figure 802-8: Water Demand Projection Summary – East Mauna Kea Aquifer Sector Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 802-14: Medium Growth Rate B Water Demand Projection by Category – East
Mauna Kea Aquifer Sector Area
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 2.8 3.0 3.3 3.5 3.8
Total with Ag* 12.4 13.2 14.0 14.8 15.8
Domestic 0.3 0.3 0.3 0.3 0.4
Industrial 0.9 1.0 1.1 1.2 1.3
Irrigation 0.0 0.0 0.0 0.0 0.0
Agriculture 9.6 10.1 10.7 11.3 12.0
Military 0.0 0.0 0.0 0.0 0.0
Municipal 1.6 1.7 1.8 1.9 2.1
Potable 1.9 2.0 2.1 2.3 2.4
Nonpotable w/o Ag* 0.9 1.0 1.1 1.2 1.4
Nonpotable w/ Ag* 10.5 11.1 11.8 12.6 13.4
DWS 1.6 1.7 1.8 1.9 2.1
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
2005 2010 2015 2020 2025
YearDemand (mgd)Nonpotable w/o Ag*
Potable
Total w/ Ag*
Total w/o Ag*
Potable
Nonpotable w/ Ag*
LEGEND: Growth Rate A Growth Rate B Growth Rate C
802 East Mauna Kea Aquifer Sector Area
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Figure 802-9: Medium Growth Rate B Water Demand Projections and Full Build-Out –
East Mauna Kea Aquifer Sector Area
0
50
100
150
200
250
300
350
400
450
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 388
LUPAG = 25–405Zoning = 8–378
Legend*, **
802 East Mauna Kea Aquifer Sector Area
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Water Use and Development Plan Update
Figure 802-10: Medium Growth Rate B Water Demand Projection by Category – East
Mauna Kea Aquifer Sector Area
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
802.4.5 DWS Historical Water Consumption Data Projections
DWS supplied water consumption was projected in 5-year increments to the year 2025 based on
DWS historical water system consumption data from 1970 to 2003, as shown on Figure 802-11.
Legend*, **
802 East Mauna Kea Aquifer Sector Area
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Figure 802-11: DWS Water Demand Projection – East Mauna Kea Aquifer Sector Area
East Mauna Kea Aquifer Sector Water Systems
0.0
0.5
1.0
1.5
2.0
2.5
1970 1980 1990 2000 2010 2020mgdHistorical Projected
Year 2005: 1.47 mgd
Year 2010: 1.59 mgd
Year 2015: 1.70 mgd
Year 2020: 1.81 mgd
Year 2025: 1.93 mgd
This graph combines data for the
Paukaa, Papaikou-Kalaoa, Hakalau,
Honomu, Pepeeko, Laupahoehoe,
Ookala, Ninole, Haina, Kukuihaele, and
Haauilo water systems.
Historical data provided by RW Beck, Inc.
Projections based on historical DWS water consumption data are slightly lower than projections
based on population growth rate. Part of the Waimea System is within the East Mauna Kea
ASEA, which is not represented on the graph.
802 East Mauna Kea Aquifer Sector Area
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802.5 RESOURCE AND FACILITY RECOMMENDATIONS
802.5.1 Water Source Adequacy
802.5.1.1 Full Build-Out
Full build-out water demands associated with the maximum density of LUPAG and Zoning land
uses are both sustainable if agricultural demands are not included. The LUPAG full build-out
requires approximately 6 percent sustainable yield of the East Mauna Kea ASEA. The existing
zoning is legally developable, and requires approximately 2 percent of the existing sustainable
yield. If worst case agricultural demands are included, the LUPAG demand exceeds the SY, and
the Zoning demand is 97 percent of the SY.
802.5.1.2 Twenty-Year Projection
Present and 20-year projected water demands are miniscule compared to the SY, even including
worst case agricultural demands.
802.5.2 Source Development Requirements
802.5.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, are evaluated to meet projected water demands.
802.5.2.1.1 Conventional Water Resource Measures
802.5.2.1.1.1 Ground Water
The East Mauna Kea ASEA has the third highest sustainable yield of the sectors on the island.
High level dike water exists in the rift zone section of Mauna Kea, and perched water is common
in the Laupahoehoe series (Refer to Figure 1.4). However, these locations are difficult to access
and at great distances from end users. Basal water is generally found up to 5 miles inland.
Existing potable water wells in the sector are in the vicinity of Hawaii Belt Road up to a few
miles from the coast. The 1990 WRPP indicates that a good deal of basal water is developable,
and specifically in the Paauilo Aquifer System Area the 60 mgd sustainable yield refers to
potable basal groundwater. DWS has several wells planned, including two new sources at
Ahualoa and Paauhau in the Haina Water System, one new source in the Ninole Water System,
one new source and one backup well in the Honomu-Hakalau Water System, one new source in
the Pepeeko Water System, one new source at Kaieie Mauka in the Papaikou Water System, and
a backup source well in each of the Paauilo and Ookala Water Systems.
Spring water is a plentiful resource in the sector area. Due to costs associated with infrastructure
improvements, treatment and monitoring, which is required to meet the rules and regulations of
802 East Mauna Kea Aquifer Sector Area
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the Federal Safe Drinking Water Act (SDWA), the usage of these sources has been reduced.
Implementing new sources may still be more expensive than developing basal groundwater
wells. However, spring sources are available to develop as a secondary potable water resource.
Spring sources that are owned by DWS but currently not in use due to the development of
groundwater sources may also be considered for non-potable use.
802.5.2.1.1.2 Surface Water
Most of the surface water used for non-potable requirements originates in the Kohala ASEA
(ASEA 801) and is transferred through the Upper and Lower Hamakua Ditch Systems. Surface
water can and should be used for localized non-potable uses. The number of stream diversions
registered with the CWRM indicates that this is already taking place.
802.5.2.1.1.3 Water Transfer
As mentioned in the previous section, transfer of non-potable source water into the East Mauna
Kea ASEA from ASEA 801 is already taking place. This is not viewed as a problem considering
the abundance of surface water in the ASEA 801.
Currently, an undetermined quantity of potable water is being transferred into the DWS Haina
System from the DWS Waimea Water System, the sources of which are streams and one high-
level groundwater well in the ASEA 801. Transfer of potable water into the East Mauna Kea
ASEA may continue due to the abundance of potable sources in both sector areas.
802.5.2.1.2 Alternative Water Resource Enhancement Measures
802.5.2.1.2.1 Rainwater Catchment Systems
Most of the developed area within the sector area receives over 60 inches of rainfall per year,
which should be adequate to support rainwater catchment systems. This is confirmed by the
quantity of domestic usage, which currently is 15 percent of all potable water used in the sector
area. Population densities in remote areas where catchment is typically used are not expected to
grow significantly and may continue to be served by catchment.
802.5.2.1.2.2 Wastewater Reclamation
Except for the Haina Water System, most of the public water systems service small populations;
therefore, the amount of reclaimed wastewater generated at each treatment plant would be
minimal. Due to the abundance of other non-potable water from other sources, reclaimed
wastewater is not viewed with large scale development potential.
802.5.2.1.2.3 Desalination
802 East Mauna Kea Aquifer Sector Area
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Desalination plants would be restricted to coastal areas where brackish groundwater can be
drawn. As potable water is readily available in these areas, desalination is not considered a
feasible alternative due to the high cost.
802.5.2.2 Demand-Side Management
802.5.2.2.1 Development Density Control
Full build-out water demand associated with LUPAG is three times that of Zoning; however,
most of the LUPAG Urban area is already classified as “Low Density”. Furthermore, water
demands are miniscule compared to the sustainable yield even with full build-out to maximum
density. Development density control is possible, but not considered necessary in the near
future.
802.5.2.2.2 Water Conservation
The average usage per connection on the DWS water systems is less than 300 gpd per
connection, which is less than the island average. Potable water consumption from all sources
per capita is estimated at 110 gpd, which is considered acceptable. Water usage rates should be
monitored, and water conservation should continue; but currently, additional water conservation
measures are not necessary.
802.5.3 Recommended Alternatives
Basal groundwater source development should continue; and consistent with the General Plan,
sources should be investigated in the Kukuihaele, Honakaa, Kaieie Mauka, Kulaimano, and
Honomu areas with the intention of replacing existing surface water sources. Specifically,
additional groundwater sources should be developed for the Haina Water System so that potable
water transfer from the Waimea Water System is not necessary, as sources in the ASEA 801
supplying the Waimea Water System should be conserved for transfer to the aquifer sector areas
on the leeward coast that could experience deficiencies in water supply in the future. In the
interim, a meter should be installed at the junctions of the Waimea and Haina Water Systems in
order to monitor the quantity of water being transferred. Usage of the existing spring sources for
potable use may continue, provided that necessary infrastructure improvements and treatment
and monitoring required to comply with Federal SDWA regulations are not cost-prohibitive.
Surface water should continue to be the primary source of non-potable water.
The AWUDP has recommended significant improvements to the Lower Hamakua Ditch system
which will properly service future diversified agricultural activities. These recommendations
may change in light of the damage sustained by the ditch systems during the recent earthquake.
803 West Mauna Kea Aquifer Sector Area
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803 WEST MAUNA KEA AQUIFER SECTOR AREA
803.1 SECTOR AREA PROFILE
803.1.1 General
The West Mauna Kea Aquifer Sector Area (ASEA) includes the Waimea Aquifer System Area
(ASYA) [80301]. Its boundaries extend from the saddle area between Mauna Kea and Mauna
Loa to Waimea and along the western shores at Kawaihae to Puako, capturing most of the South
Kohala district and the western portion of the Hamakua district.
Average annual rainfall ranges from 9 inches along the coast to nearly 50 inches, however most
of the sector receives less than 30 inches, making this sector area one of the driest on the island.
The sustainable yield is 24 mgd.
803.1.2 Economy and Population
803.1.2.1 Economy
Tourism has become the leading economic industry in South Kohala. One of South Kohala’s
three luxury resorts, the Mauna Kea Resort, which includes two hotels and ten exclusive
residential neighborhoods, lies within the West Mauna Kea ASEA.
Agriculture also continues to be a major economic contributor. Cattle ranching utilizes most of
the agricultural land area, with pastures running from high mountain slopes to sea level. Parker
Ranch, one of the nation’s largest ranches, spreads approximately 175,000 acres of land. In
addition to producing United States Department of Agriculture (USDA) choice beef from
between 30,000 and 35,000 cattle annually, Parker Ranch’s businesses include visitor activities,
commercial leasing and real estate holdings.
As indicated in the General Plan, “Waimea is one of the most productive areas for vegetable
crops on the Big Island” and “the agricultural industry…has the potential for further expansion.”
The Canada-France-Hawaii Telescope Corporation, which has a telescope atop Mauna Kea, has
a base facility south of Waimea in the West Mauna Kea ASEA with a staff of 51 and an annual
operating budget of $6.2 million. Astronomical facilities within the 11,228-acre Mauna Kea
Science Reserve are located within the West Mauna Kea ASEA. With 13 observatories and 12
of the world’s state-of-the-art telescopes, Mauna Kea is considered the world’s premier site for
ground-based astronomical observatories. Astronomy generates over $619 million in capital
investments and approximately 270 permanent jobs.
803.1.2.2 Population
Nearly all of the population contributing to the water demand of the sector area is within the
South Kohala District. The growth in tourism has followed the dramatic increase in the
803 West Mauna Kea Aquifer Sector Area
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population of South Kohala over the past 30 years; and as a result, South Kohala enjoyed the
lowest unemployment rate and the highest median income in 1997.
Table 803-1: Historical Population
1980 1990 2000
1980-90
% Change
1990-2000
% Change
2,084 4,134 5,939 98.4 43.7
Data Source: 2000 U.S. Census
Data redistributed and evaluated for West Mauna Kea Aquifer Sector Area
Table 803-2: Population Projection
Growth
Rate 2000 2005 2010 2015 2020
2000-10
% Change
2010-20
% Change
A – Low 5,939 7,060 8,153 9,392 10,831 37.3 32.8
B – Medium 5,939 7,082 8,224 9,531 11,048 38.5 34.3
C – High 5,939 7,378 8,740 10,279 12,042 47.2 37.8
Data Source: County General Plan, February 2005
Data redistributed and evaluated for West Mauna Kea Aquifer Sector Area
803.1.3 Land Use
803.1.3.1 Hawaii County General Plan
The Hawaii County General Plan Land Use Pattern Allocation Guide Map for the West Mauna
Kea ASEA is shown on Figure 803-1. The estimated land use allocation acreage for each
LUPAG designation within the sector area is listed in Table 803-3.
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Table 803-3: LUPAG Map Estimated Land Use Allocation Acreage – West Mauna Kea
Aquifer Sector Area
LAND USE PATTERN ACREAGE
% of
TOTAL
High Density Urban 0 0
Medium Density Urban 567 0.3
Low Density Urban 2,516 1.3
Industrial 915 0.5
Important Agricultural Land 47,663 24.8
Extensive Agriculture 73,087 38.1
Orchard 0 0
Rural 927 0.5
Resort/Resort Node 554 0.3
Open 8,283 4.3
Conservation 54,057 28.2
Urban Expansion 3,407 1.8
University Use 0 0
TOTAL 191,976 100.0
The water utility courses of action for South Kohala in the Hawaii County General Plan are as
follows:
(a) Seek alternative sources of water for the Lalamilo system.
(b) Improve and replace inadequate distribution mains and steel tanks.
(c) Continue to seek additional groundwater sources for the Waimea System.
803.1.3.2 Hawaii County Zoning
Hawaii County Zoning for the West Mauna Kea ASEA is shown on Figure 803-2. The
estimated land use allocation acreage for each zoning class within the sector area is listed in
Table 803-4.
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Table 803-4: County Zoning Estimated Class Allocation Acreage – West Mauna Kea
Aquifer Sector Area
ZONING CLASS ACREAGE
% of
TOTAL
Single Family Residential 2,391 1.3
Multi-Family Residential
(including duplex) 332 0.2
Residential-Commercial Mixed Use 0 0
Resort 82 0.0
Commercial 123 0.1
Industrial 39 0.0
Industrial-Commercial Mixed 0 0
Family Agriculture 0 0
Residential Agriculture 648 0.3
Agriculture 125,786 65.5
Open 7,738 4.0
Project District 0 0
Forest Reserve 53,826 28.0
(road) 1,003 0.5
TOTAL 191,969 100.0
803.2 EXISTING WATER RESOURCES
803.2.1 Ground Water
The West Mauna Kea ASEA has a sustainable yield of 24 mgd. According to the CWRM
database, there are 30 production wells in the sector area, including 15 municipal, 11 irrigation, 2
industrial, 2 other. There are also 7 wells drilled and categorized as “unused.” Refer to
Appendix B for this database. Figure 803-3 shows the well locations.
803.2.2 Surface Water
The Waikoloa Stream south of Waimea is classified in the HSA as perennial but intermittent at
lower elevations.
There are 7 declared stream diversions in the CRWM database listed in Table 803-5 and shown
on Figure 803-4; however, flow data is not available for the stream diversions.
803 West Mauna Kea Aquifer Sector Area
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Figure 803-3: Well and Tunnel Location
MAP CURRENTLY NOT AVAILABLE ON-LINE
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Figure 803-4: Streams & Diversions
MAP CURRENTLY NOT AVAILABLE ON-LINE
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Table 803-5: Stream Diversions – West Mauna Kea Aquifer Sector Area
FILE REFERENCE TMK STREAM NAME
STATE PARK HAW 4-4-015:001 Hopukani Spring (East) Spring diversion, pipe from Hopukani Spring
#1. See also new entry for declarant.
STATE PARK HAW 4-4-015:001 Hopukani Spring (West) Spring diversion, pipe from Hopukani Spring
#2. See also new entry for declarant.
STATE PARK HAW 4-4-016:003 Waihu Spring Spring diversion, pipe from Waihu Spring (new
entry).
STATE PARK HAW 4-4-016:003 Liloe Spring Spring diversion, pipe from Liloe Spring (new
entry).
WALLACH K 6-2-009:004 Keanuiomano Stream diversion, pump from Keanuiomano
Stream. Use when stream is running.
BALDWIN E 6-2-009:018 Keanuiomano Stream diversion, 2 pipes from Keanuiomano
Stream. Two pipes at one location.
PARKER RANCH 6-6-001:038 Resevoir Stream diversion, Lihue Intake from reserve
overflow.
803.2.3 Reclaimed Wastewater
There are 2 wastewater reclamation facilities (WWRF) in the sector area. Table 803-6 lists the
WWRF, reclaimed water classification, facility treatment capacity, current reuse amount, and
current application.
Table 803-6: Wastewater Reclamation Facilities – West Mauna Kea Aquifer Sector Area
Wastewater
Reclamation Facility
Reclaimed
Water
Classification
WWRF
Capacity
(MGD)
Current
Reuse
Amount
(MGD)
Irrigation Application
South Kohala
Wastewater Corp. R-2 0.6 0.27
Mauna Kea Golf Course – golf
course irrigation
Waimea Wastewater
Company WRF R-3 0.1 0.045 Parker Ranch – pasture irrigation
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803.3 EXISTING WATER USE
803.3.1 General
The total estimated average water use within the West Mauna Kea ASEA from 2004 to 2005
(DWS meter data and CWRM pumpage data from November 2004 through October 2005,
available GIS data, estimates from the 2003 SWPP, and estimated reclaimed wastewater usage)
is listed in Table 803-7. The Waikoloa private water system operated by the West Hawaii Water
Company supplied the largest quantity of the total estimated water use within the sector area.
Table 803-7 and Figure 803-5 summarize water use in accordance with CWRM categories and
indicate separately the quantities supplied excluding agricultural demands, and the quantities
supplied including worst case agricultural demands (described in Chapter 2) by the DWS system,
non-DWS systems, and reclaimed wastewater.
Table 803-7: Existing Water Use by Categories – West Mauna Kea Aquifer Sector Area
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.01 0.2 0.1
Industrial 0.00 0.0 0.0
Irrigation 0.66 8.5 6.0
Reclaimed WW 0.32 4.1 2.9
Agriculture 3.34 0.0 30.2
Military 0.00 0.0 0.0
Municipal
DWS System 2.17 28.2 19.7
Private Public WS 4.56 59.1 41.2
Total without Ag* 7.71 100.0
Total with Ag* 11.05 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
803 West Mauna Kea Aquifer Sector Area
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Figure 803-5: Existing Water Use by Categories – West Mauna Kea Aquifer Sector Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 803-6 generally shows the service area for the various water systems and indicates the
extent of the DWS water system.
803.3.2 Domestic Use
Domestic use or water use by individual households is nominal, and is assumed to be supplied by
private individual rainwater catchment systems.
803.3.3 Industrial Use
There are two drilled wells classified as “Industrial” in the CWRM database, owned by Mauna
Kea Beach Hotel; however, neither have reported pumpage.
803.3.4 Irrigation Use
Irrigation is based on pumpage reported for private wells categorized by CWRM as irrigation
wells and reclaimed water use as indicated earlier in Table 803-7. Table 803-8 lists the average
private irrigation well pumpage reported to the CWRM or listed in the 2003 SWPP.
Domestic 0.2%
Industrial 0.0%
Irrigation 8.5%
Irrigation (Recl'd
WW) 4.1%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 59.1%
Municipal
(DWS) 28.2%
Domestic 0.1%
Industrial 0.0%
Irrigation 6.0%
Irrigation (Recl'd
WW) 2.9%
Agriculture 30.2%
Military 0.0%
Municipal
(Non-DWS) 41.2%
Municipal
(DWS) 19.7%
w/o Agricultural Water Use* with Agricultural Water Use*
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Table 803-8: Private Irrigation Well Pumpage
Private Irrigation Irrigation Well Pumpage (mgd)
Mauna Lani Resort 0.62
Mauna Kea Properties Not Reported
Arlin Trust 0.01
Hapuna State Recreation Area 0.028*
TOTAL 0.66
*Source: 2003 SWPP, Volume 2, Island of Hawaii
Records indicate that the Mauna Kea Beach Resort has brackish water wells for golf course
irrigation, however none reported pumpage. The Mauna Lani Resort owns three irrigation wells
in the West Mauna Kea ASEA.
The Hapuna State Recreation Area is located south of Kawaihae and is managed by the DLNR,
State Parks division. Potable water demand is supplied by the DWS Waimea Water System.
Nonpotable water is pumped from a single well with a safe source capacity of 0.33 mgd and
stored in a reservoir which feeds the irrigation system. Safe source capacity is described in the
2003 SWPP as two-thirds of the installed pump capacity,
803.3.5 Agricultural Use
Parker Ranch has a vast water system to service its numerous pasture lots, which consists of 175
miles of pipeline, 9 reservoirs, 145 water tanks, 40 ground tanks, 3 water dams and 650 water
troughs. The Ranch also purchases water from the DWS where such supply is available. Since
the sources for the Ranch livestock are stream diversions, yearly consumption varies depending
on the weather and its related rainfall. The Ranch has a prepared master plan for residential,
commercial, and other related uses. It is called the Parker Ranch 20/20 Plan.
The farm lots in Lalamilo and Puukapu utilize the Waimea Irrigation System. The pressurized
distribution system consists of pipelines varying between 8 and 18 inches in diameter.
According to the AWUDP, in 2003 the system drew 0.908 mgd from 117 metered accounts. The
source water for the system is stream diversions from the Kohala Mountain watersheds, which
lie within the Kohala ASEA (801).
803.3.6 Military Use
There is no military use in the West Mauna Kea ASEA.
803.3.7 Municipal Use
Municipal use can be subcategorized into the other water use categories, namely Domestic,
Industrial, Irrigation, Agriculture, and Military, if detailed information is available.
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803.3.7.1 County Water Systems
The DWS has two major water systems that service the sector area. The Waimea Water System
(WS) covers the mauka areas and the Lalamilo WS services the coastal areas. Refer to Figure
803-6.
The Waimea WS described in Chapter 801 spans three aquifer sector areas, serving areas within
the West Mauna Kea ASEA south of Mamalahoa Highway, including the residential lots at
Puukapu-Nienie and Kamuela Airport.
The Lalamilo WS was originally designed to service the small village of Kawaihae. A 2-inch
pipeline transported water from the Waimea WS down to Kawaihae, generally following
Kawaihae Road. In the 1950’s, the State developed the Puako subdivision and a deep draft
harbor at Kawaihae. This necessitated replacement of the existing small lines and extension of
the system to Puako. The small pipeline from Waimea to Kawaihae was replaced with a 6-inch
pipeline and additional storage tanks were erected. In the 1960’s, the Rockefeller development
at Mauna Kea Beach opened a new era for this region. To develop sufficient supply, high level
exploratory deep wells were attempted along Kawaihae Road. This resulted in marginal quality
water with high chloride content. The high chloride content and temperature reflected the
geothermal anomaly which occurs in this area. However, these wells supplemented the limited
supply from Waimea. Water from the wells was blended with the fresh mountain water to
supply the emerging developments. Based on the success of the adjacent Waikoloa deep wells,
the State drilled an exploratory well on the State lands of Lalamilo at an elevation of
approximately 1,200 feet in 1977. The well produced water of good quality with a chloride
content of 78 ppm. Subsequently, additional wells were drilled with financing by the Mauna
Lani Resort developer which allowed Mauna Lani and Mauna Kea resorts to expand their
facilities. The Kawaihae Village area around the harbor has also expanded, and is served
by the Lalamilo WS. The two Parker Wells replaced the two Kawaihae Wells in the late 1990’s.
The system presently services the area from Kawaihae to Mauna Lani in five operational zones,
through two booster pump stations and nine storage tanks.
DWS water use is subcategorized in Table 803-9 to the extent possible based on available meter
data and is depicted in Figure 803-7. “Other Municipal” includes facilities such as schools, and
various commercial, government, medical and nonprofit entities which have mixed water use and
cannot be specifically allocated to the other categories.
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Table 803-9: DWS Existing Water Use by Categories – West Mauna Kea Aquifer Sector
Area
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 0.59 27.3
Industrial 0.00 0.0
Irrigation 0.00 0.0
Agriculture 0.09 4.0
Military 0.00 0.0
Other Municipal 1.49 68.6
Total 2.17 100.0
Figure 803-7: DWS Existing Water Use by Categories – West Mauna Kea Aquifer Sector
Area
Domestic 27.3%
Industrial 0.0%
Irrigation 0.0%
Agriculture 4.0%
Military 0.0%
Other Municipal
68.6%
803.3.7.2 State Water Systems
The DLNR, Division of State Parks owns the Mauna Kea State Park water system located on the
southwestern side of Mauna Kea on Saddle Road. In exchange for water use by the Pohakuloa
Training Area (PTA), the water system sources and transmission lines are maintained by the U.S.
Army. The PTA is located in the Northwest Mauna Loa ASEA (807). Sources of water for the
system are from five springs, namely Upper Hopukani Spring, Hopukani Spring, Waihu Spring,
Lilole Spring and an unnamed spring. The spring water is gravity fed through two above ground
803 West Mauna Kea Aquifer Sector Area
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2-inch galvanized pipelines into three 420,000 gallon steel storage reservoirs, then filtered and
disinfected with sodium hypochlorite prior to distribution. There are 13 service connections
which include the Mauna Kea State Park, the PTA and service to approximately 25 people. The
estimated park demand is 0.015 mgd.
803.3.7.3 Federal Water Systems
There are no Federal water systems in the West Mauna Kea ASEA.
803.3.7.4 Private Public Water Systems
There are two private public water systems within the West Mauna Kea ASEA regulated by the
Department of Health, which supply a significant percentage of the total estimated water use
within the sector. Table 803-10 lists the average pumpage each system reported to the CWRM,
and is assumed to be the system water use.
Table 803-10: Private Public Water System Water Use – West Mauna Kea Aquifer Sector
Area
Private Public Water System
Water Use
(mgd)
Waikoloa 4.50
Waikii Ranch 0.04
The Waikoloa Resort lands were purchased in 1968 from Parker Ranch by Boise Cascade. The
lands are split between the West Mauna Kea ASEA and the Northwest Mauna Loa ASEA (807),
with the higher elevation lands above the beach resort used for residential development within
the former and the oceanfront lands used for resort hotel development within the latter. Five
wells located within the West Mauna Kea ASEA provide potable water for all of the
developments. DOH records indicate that the system serves a population of 9,960 through 1,629
service connections.
The Waikii Ranch is a 2,995-acre ranch lot subdivision at elevations 3,800 feet to 4,800 feet on
the west slopes of Mauna Kea along the Saddle Road. The potable water source is two deep
wells at ground elevations in excess of 4,300 feet with a total pump capacity of 288,000 gallons
per day. The water system also includes two booster pump stations and three concrete reservoirs
and approximately 8 miles of 6-inch ductile iron watermain.
803.3.8 Water Use by Resource
803.3.8.1 Ground Water
Table 803-11 summarizes the current production, potential production (16 and 24-hour
operation), sustainable yield (SY), and percentage of SY for the various productions calculated.
Current production is represented by the highest 12-month moving average (MAV) or the
803 West Mauna Kea Aquifer Sector Area
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highest annual average yield calculated from the actual pumpage data. Potential well production
is based on installed pump capacities, and calculated for both 16 hours of operation a day and 24
hours of operation a day. Data is based on pumpage data reported to CWRM.
Table 803-11: Sustainable Yield – West Mauna Kea Aquifer Sector Area
Sys Code System Area
High
12-Month
MAV
(MGD)
Potential
16 -Hour
Production
(MGD)
Potential
24-Hour
Production
(MGD) SY (MGD)
High
12-Month
MAV SY
(%)
Potential
16-Hour
Production SY
(%)
Potential
24-Hour
Production SY
(%)
9.13 17.56 26.34 24 38.04 73.17 109.75
80301 Waimea 9.13 17.56 26.34 24 38.04 73.17 109.75
Based on available information from the CWRM database, the current groundwater use is over a
third of the sustainable yield. If the installed pumps operate 16-hours a day, close to three-
quarters would be used, and if the installed pumps operate continuously, the sustainable yield
would be exceeded.
803.3.8.2 Surface Water
Parker Ranch has one declared stream diversion in the West Mauna Kea ASEA; however,
consumption is not known.
According to the SWPP, the estimated source capacity from the five springs serving the Mauna
Kea State Park water system is 0.00125 mgd, which is not adequate to meet the existing
consumption of the Park and the PTA.
803.3.8.3 Rainwater Catchment
Water consumption calculated for developed parcels that are not supplied by groundwater or
surface water is assumed to be supplied by rainwater catchment. The water use categorized as
Domestic Use previously in Table 803-7 is assumed to be supplied by individual catchment
systems.
803.3.8.4 Reclaimed Wastewater
Reclaimed wastewater from the two wastewater treatment plants within the West Mauna Kea
ASEA is used for golf course and pasture lot irrigation. Refer to Table 803-6, presented earlier.
803 West Mauna Kea Aquifer Sector Area
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803.4 FUTURE WATER NEEDS
803.4.1 General
Table 803-12 summarizes the LUPAG, Zoning and 5-year incremental water demand projection
scenarios for the total aquifer sector area and the individual aquifer system area. The sustainable
yield (SY) is presented to draw comparisons.
Table 803-12: Summary of Demand Projections
Growth Rate B Demand Projections (mgd)Without
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total W. Mauna Kea ASEA 24 52.1 13.8 7.7 9.0 10.4 12.0 13.9
80301 – Waimea ASYA 24 52.1 13.8 7.7 9.0 10.4 12.0 13.9
Growth Rate B Demand Projections (mgd)With
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total W. Mauna Kea ASEA 24 186.7 150.6 11.0 12.8 14.9 17.2 20.0
80301 – Waimea ASYA 24 186.7 150.6 11.0 12.8 14.9 17.2 20.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
There is only one aquifer system area within the West Mauna Kea ASEA; therefore, demands
presented by aquifer sector area and by aquifer system area are one in the same.
803.4.2 Full Build-Out Water Demand Projections
The full build-out water demand projections based on the General Plan and County Zoning for
the West Mauna Kea ASEA are listed in Tables 803-13 and 803-14, and reflect refinement as
discussed below. Each land use class is associated with the most appropriate CWRM water use
category.
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Table 803-13: Hawaii County General Plan Full Build-Out Water Demand Projection –
West Mauna Kea Aquifer Sector Area
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 22.1
Urban Expansion Domestic/Irrigation/Municipal 15.4
Resort Irrigation/Municipal 9.4
Industrial Industrial 3.7
Agriculture Agriculture 134.6
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 0.9
DHHL Irrigation/Municipal 0.6
TOTAL w/o Ag* 52.1
TOTAL w/ Ag* 186.7
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 803-14: County Zoning Full Build-Out Water Demand Projection – West Mauna
Kea Aquifer Sector Area
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 11.5
Resort Irrigation/Municipal 1.1
Commercial Municipal 0.4
Industrial Industrial 0.2
Agriculture Agriculture 136.8
DHHL Irrigation/Municipal 0.6
TOTAL w/o Ag* 13.8
TOTAL w/ Ag* 150.6
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
803.4.2.1 Refine Land Use Based Projection
803.4.2.1.1 State Water Projects Plan
The total projected demand to the year 2020 for 19 State Water Projects within the West Mauna
Kea ASEA is 15.66 mgd, 0.31 mgd using potable, 15.30 mgd using nonpotable, and 0.06
nonpotable using potable sources. The total demand exceeds the projected 2020 water demand
for the sector area; however, it is anticipated that the nonpotable demands will be supplied by
nonpotable sources. Furthermore, it is anticipated that the next phase of the AWUDP will
examine projections and sources in greater detail. The projects which will generate the most
significant demands, with the exception of DHHL projects, which are covered separately, are
listed in Table 803-15.
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Table 803-15: Future State Water Projects to Generate Significant Demands
Project Name
Primary Use
State
Department
2020 Demand
(mgd)
Future Subdivision in Honokaa Nonpotable DOA 7.00
Future Subdivision in Paauilo Nonpotable DOA 1.25
Waimea/Paauilo Watershed Project Nonpotable DOA 4.00
803.4.2.1.2 State Department of Hawaiian Home Lands
The three Puukapu Sections are existing pre-1994 DHHL tracts totaling about 12,000 acres.
Puukapu 1 is comprised of three parcels totaling 392 acres, and generally located in the southeast
section of Waimea. Some pasture lots have already been awarded. Together the existing and
potential pastoral developments have a potable water need of 0.13 mgd and an irrigation water
need of 0.48 mgd. Potable water supply would be from the DWS Waimea Water System.
Irrigation water supply would be from the Waimea Irrigation System.
803.4.2.1.3 Agricultural Water Use and Development Plan
The AWUDP estimates the 20-year service area of the Waimea Irrigation System between 712
and 880 acres, which, using an estimated 3,400 gpd/acre, translates to a water demand of 2.42 to
2.99 mgd. As discussed, this report presents a range of agricultural nonpotable water use in the
demand projections. It is anticipated that the next phase of the AWUDP will examine the sources
and demand requirements in greater detail.
803.4.3 Water Use Unit Rates
Water use unit rates are based on the Water System Standards as discussed in Chapter 1, and
single family residential (Low Density Urban category of the General Plan and RS-7.5 and
greater or Single-Family Residential categories of one lot per at least 7,500 square foot of
County Zoning) consumption is 2.5 units per lot based on historical consumption data.
803.4.4 5-Year Incremental Water Demand Projection to the Year 2025
The following section presents 5-year incremental water demand projections to the year 2025 for
the West Mauna Kea ASEA. The projected low, medium, and high growth rates are listed in
Table 803-16, and are graphed in Figure 803-8. Potable and nonpotable water demands are also
differentiated.
Focusing on Medium Growth Rate B, Figure 803-9 illustrates the magnitude of the sustainable
yield, both LUPAG and Zoning full build-out water use, and water use projection through the
year 2025. Figure 803-10 shows the breakdown of water demand projections by CWRM
categories through the year 2025. Table 803-17 summarizes these figures.
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Table 803-16: Water Demand Projection – West Mauna Kea Aquifer Sector Area
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 7.7 8.9 10.3 11.8 13.6 11.0 12.8 14.7 16.9 19.5
Potable 6.7 7.8 9.0 10.3 11.9 6.7 7.8 9.0 10.3 11.9
Nonpotable 1.0 1.1 1.3 1.5 1.7 4.3 5.0 5.7 6.6 7.6
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 7.7 9.0 10.4 12.0 13.9 11.0 12.8 14.9 17.2 20.0
Potable 6.7 7.8 9.1 10.5 12.2 6.7 7.8 9.1 10.5 12.2
Nonpotable 1.0 1.1 1.3 1.5 1.8 4.3 5.0 5.8 6.7 7.8
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 7.7 9.1 10.7 12.6 14.7 11.0 13.1 15.4 18.0 21.1
Potable 6.7 8.0 9.4 11.0 12.9 6.7 8.0 9.4 11.0 12.9
Nonpotable 1.0 1.2 1.4 1.6 1.9 4.3 5.1 6.0 7.0 8.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
803 West Mauna Kea Aquifer Sector Area
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Water Use and Development Plan Update
Figure 803-8: Water Demand Projection Summary – West Mauna Kea Aquifer Sector
Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 803-17: Medium Growth Rate B Water Demand Projection by Category – West
Mauna Kea Aquifer Sector Area
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 7.7 9.0 10.4 12.0 13.9
Total with Ag* 11.0 12.8 14.9 17.2 20.0
Domestic 0.0 0.0 0.0 0.0 0.0
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 1.0 1.1 1.3 1.5 1.8
Agriculture 3.3 3.9 4.5 5.2 6.0
Military 0.0 0.0 0.0 0.0 0.0
Municipal 6.7 7.8 9.1 10.5 12.2
Potable 6.7 7.8 9.1 10.5 12.2
Nonpotable w/o Ag* 1.0 1.1 1.3 1.5 1.8
Nonpotable w/ Ag* 4.3 5.0 5.8 6.7 7.8
DWS 2.2 2.5 2.9 3.4 3.9
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
5.0
10.0
15.0
20.0
25.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
5.0
10.0
15.0
20.0
25.0
2005 2010 2015 2020 2025
YearDemand (mgd)Potable
Total w/ Ag*
Nonpotable w/ Ag*
Potable
Total w/o Ag*
Nonpotable w/o Ag*
LEGEND: Growth Rate A Growth Rate B Growth Rate C
803 West Mauna Kea Aquifer Sector Area
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Figure 803-9: Medium Growth Rate B Water Demand Projections and Full Build-Out –
West Mauna Kea Aquifer Sector Area
0
20
40
60
80
100
120
140
160
180
200
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 24
LUPAG = 52–187
Zoning = 14–151
Legend*,**
Addendum No. 1, 2/3/2012
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Figure 803-10: Medium Growth Rate B Water Demand Projection by Category – West
Mauna Kea Aquifer Sector Area
0.0
5.0
10.0
15.0
20.0
25.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
803.4.5 DWS Historical Water Consumption Data Projections
DWS supplied water consumption was projected in 5-year increments to the year 2025 based on
DWS historical water system consumption data from 1970 to 2003, as shown on Figure 803-11.
Legend*, **
803 West Mauna Kea Aquifer Sector Area
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Figure 803-11: DWS Water Demand Projection – West Mauna Kea Aquifer Sector Area
Lalamilo Water System
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
1970 1980 1990 2000 2010 2020mgdHistorical Projected
Year 2005: 3.76 mgd
Year 2010: 4.30 mgd
Year 2015: 4.85 mgd
Year 2020: 5.40 mgd
Year 2025: 5.94 mgd
Historical data and graph provided by RW Beck, Inc.
Over half of the Lalamilo Water System, and a small part of the Waimea Water System are
within the West Mauna Kea ASEA, therefore, the former was included in the graph above; the
latter was not. Projections based on historical DWS water consumption data and projections
based on population growth rate cannot be compared as representation of the same area;
however, the rate of increase based on population projections are significantly greater than the
historical growth rate of the demand.
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803.5 RESOURCE AND FACILITY RECOMMENDATIONS
803.5.1 Water Source Adequacy
803.5.1.1 Full Build-Out
Full build-out water demands associated with the maximum density of LUPAG land uses are not
sustainable. If agricultural demands are not included, the LUPAG full build-out water demand
requires over twice the sustainable yield (SY) of the West Mauna Kea Aquifer Sector Area
(ASEA), and nearly eight times the SY if worst case agricultural demands are included. The
existing zoning is legally developable, and requires nearly 60 percent of the existing sustainable
yield if agricultural demands are not included, and over six times the SY if worst case
agricultural demands are included.
803.5.1.2 Twenty-Year Projection
The 2025 water demand projection is nearly 60 percent of the SY not including agricultural
demands, and over 80 percent of the SY if worst case agricultural demands are included.
Existing water demands range between 32 and 46 percent of the SY of the sector area.
803.5.2 Source Development Requirements
803.5.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, are evaluated to meet projected water demands.
803.5.2.1.1 Conventional Water Resource Measures
803.5.2.1.1.1 Ground Water
Measurements of the chloride content and height of the basal aquifer in the vicinity of the
Lalamilo well field indicate that the quality and potential of this source is lower than the
adjoining Waikoloa well field; however, the two Parker wells have shown good results.
Kawaihae wells also have a high chloride content and indicate the presence of a geothermal
anomaly. Nearby irrigation wells used by Mauna Kea Properties showed high chlorides. These
may be reactivated if needed; however, production must be viewed with caution, because the
high chloride content may be an indication that the potable basal aquifer is overdrawn.
Impact on the basal aquifer is of high concern because of the proximity of the wells to each other
and the large volumes of withdrawal. Although pumpage is not reported to the CWRM, Mauna
Kea Properties owns five wells classified as “Irrigation.” Mauna Lani Resort owns three wells
classified as “Irrigation,” one of which reports pumpage. Overpumping of the lower level
brackish water wells could possibly cause salt water intrusion into the freshwater lens and
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adversely affect the salinity of the nearby potable water wells. Additional nonpotable wells will
need to be carefully placed and monitored.
Exploration should be continued to determine the extent and volume of high level water. The
WRPP indicates that high level dike water occurs at great depth in the Hamakua formation
towards the crest of Mauna Kea. The Waikii Ranch wells at elevation 4,350 feet above sea level,
tap high level water at an elevation over 1,500 feet above sea level.
803.5.2.1.1.2 Surface Water
The Waikoloa Stream and associated tributaries generally run parallel to Kawaihae Road,
flowing into the ocean on the north side of the Mauna Kea Resort. The proximity to
development areas suggests it is a promising resource for both potable and nonpotable uses. The
stream is intermittent at lower elevations. The USGS has several gauges on the stream and its
tributaries. Additional stream flow studies would be required to evaluate the potential as a water
resource.
803.5.2.1.1.3 Water Transfer
Water already is being transferred both out of and into the West Mauna Kea ASEA. All of the
source wells for both the DWS Lalamilo Water System (WS) and the private Waikoloa System
are located in the West Mauna Kea ASEA. Both systems supply developments in the Northwest
Mauna Loa ASEA (807). Conversely, the well and stream sources supplying the DWS Waimea
WS, part of which is in the West Mauna Kea ASEA, are in the Kohala ASEA (801). ASEA 801
has an abundance of both groundwater and surface water. The Waimea and Lalamilo WSs are
interconnected by a valved connection. Development of sources in the ASEA 801 and
subsequent transfer to the DWS Lalamilo WS within the West Mauna Kea ASEA could be easily
accomplished.
803.5.2.1.2 Alternative Water Resource Enhancement Measures
803.5.2.1.2.1 Rainwater Catchment Systems
West Mauna Kea is one of the drier sector areas on the island. Although areas in Waimea near
the northeastern boundary receive upward of 50 inches per year, most of the area in the sector
receives less than 30 inches per year, which is not enough to sustain rainwater catchment
systems.
803.5.2.1.2.2 Wastewater Reclamation
The two wastewater reclamation facilities currently produce 0.315 mgd and are expandable to
0.7 mgd. Effluent from the facility at Mauna Kea Resort is currently combined with brackish
water to irrigate the golf course. Future irrigation uses are likely to follow increased
development of the resort. Proximity to the facility may not be enough to promote usage, as the
purveyor currently charges $0.35 per 1,000 gallons. Reclaimed wastewater from the Waimea
803 West Mauna Kea Aquifer Sector Area
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WRF used on Parker Ranch’s pasture lots is expected to continue, however additional usage will
depend on development in the immediate vicinity requiring nonpotable water.
803.5.2.1.2.3 Desalination
Desalination is a potential source of potable water from brackish wells in the lower lying areas.
Chloride content of existing nonpotable wells is generally less than 500 ppm, which would be
suitable for desalination. Typically, brackish water with chlorides less than 5,000 ppm is
desirable for desalination. As described previously, brackish water should not be overdrawn,
therefore the quantity of water available for desalination may be limited. Minimization of
pumping costs would be desired to make this alternative feasible, thus restricting the service area
to coastal regions such as Mauna Kea Resort and Kawaihae.
803.5.2.2 Demand-Side Management
803.5.2.2.1 Development Density Control
Full build-out of LUPAG demands nearly four times the amount of water than full build-out of
Zoning, largely due to the greater proportion of Urban area in LUPAG. Additionally, Urban
Expansion areas comprise over half of the Urban areas. Therefore, controlling the development
densities of Urban Expansion areas, as well as re-assessing LUPAG Urban area densities could
greatly reduce the full build-out water demand.
803.5.2.2.2 Water Conservation
The extremely high average water use unit rate per connection in the DWS water system of over
4,000 gpd can likely be attributed to the large water users in the Mauna Kea Resort. However,
DWS accounts classified as “Residential” still consume over 1,000 gpd per connection. The
estimated per capita potable water usage from all sources is over 900 gpd, which is also
extremely high. This suggests that either a significant quantity of water is being used by the
transient population or most people are using a considerable amount of water for non-domestic
purposes, such as landscaping. Clearly, there is much room for conservation by resort and
residential users. Requirements for efficient irrigation equipment and practices and usage
restrictions during drier and warmer periods may be implemented. Several measures may be
considered to reduce the residential unit rate consumption, including education, plumbing code
regulation, and a rate structure deterring excessive water use. These measures may be more
strictly enforced, justified by the climate and limited potable water sources.
Unaccounted water amounts to less than 10 percent of the source water produced in the Waimea
WS, therefore supply-side conservation measures to reduce losses would not have a significant
impact compared to the associated costs.
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803.5.3 Recommended Alternatives
Development of potable basal groundwater should proceed with caution in the Lalamilo WS, and
confirmation of its availability should precede expansion of the service area and/or demand in
the system. Consistent with the Utility Courses of Action recommended in the General Plan,
alternative sources of water for the Lalamilo WS should be sought. Studies should be initiated
evaluating these potential alternative sources. Alternatives may include the following:
development of sources in the Waimea area within the Kohala ASEA (801) and transfer of water
via the Waimea WS, development of surface water sources from the Waikoloa Stream, and
desalination of brackish water from low lying wells.
Demand-side water conservation programs should be implemented with the goal of reducing
residential unit consumption rates closer to the island average.
The concept of utilizing the highest quality water for the highest end use should continue to be
followed. Such is evident in the resort complexes where reclaimed wastewater and brackish
water is already used for irrigation purposes. These sources should be expanded as additional
irrigation requirements arise. The feasibility of a nonpotable water system within the resort
should also be explored. A study of the potable water system within the resort would be prudent,
with the objective of identifying potential areas where potable water consumption can be reduced
and/or replaced.
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804 NORTHEAST MAUNA LOA AQUIFER SECTOR AREA
804.1 SECTOR AREA PROFILE
804.1.1 General
The Northeast Mauna Loa Aquifer Sector Area (ASEA) includes the Hilo [80401] and the Keeau
[80402] Aquifer System Areas (ASYA). Geographically, the sector area covers a rectangular
area from a western limit along the summit of Mauna Loa to the base of Mauna Kea to the
coastline stretching from Hilo Bay south to Keeau. The sector includes the southern halves of
the North Hilo and South Hilo districts, as well as northernmost slices of the Puna and Kau
districts. The bulk of urban Hilo and Keeau fall within this sector area.
Coastal areas average less than 150 inches a year in rainfall increasing to over 250 inches per
year in the higher elevations of Kaumana. Near the summit of Mauna Loa, rainfall averages less
than 15 inches per year. The sustainable yield (SY) of the Hilo ASYA is 347 mgd, and the SY of
the Keeau ASYA is 393 mgd, combining for a total SY of 740 mgd for the entire sector area, the
highest of all aquifer sector areas on the island.
804.1.2 Economy and Population
804.1.2.1 Economy
Hilo is the center of business, industry and government in Hawaii County. Although visitor
accommodations have steadily declined in the last 30 years, Hilo still attracts upward of 30
percent of the County’s visitors. The continued growth of the cruise ship industry, with annual
expenditures in the $20 million range, has also made a significant impact on the economy. Other
major sources of income include the international airport, the University of Hawaii at Hilo, and
two shopping centers. Manufacturing operations, such as the processing of fruit, food and
livestock, and garment manufacturing are also located in Hilo.
Sugar used to be the largest single industry in the South Hilo district. Today, the commercial
growing of ornamental plants is the most significant agricultural product, accounting for over
half of the County’s revenues from flowers and nursery products. Bananas and papayas are also
significant agricultural products.
According to the General Plan, “Hilo with its population size, harbor and airport facilities, higher
education complex, and new investment has potential for economic growth. However, many
public facilities…rely heavily on state funds and must compete with other areas of the State,”
and “New economic based activities in East Hawaii are needed if the City is to continue its role
as the island’s commercial and service center in the future.” The General Plan indicates several
projects that could boost the economy, including improvements to Saddle Road, and a post-
harvest fruit treatment plant and a call center, both already in operation.
804 Northeast Mauna Loa Aquifer Sector Area
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804.1.2.2 Population
Most of the population contributing to the demands from the Northeast Mauna Loa ASEA is
within the South Hilo District, specifically within urban Hilo. Much of the growth within the
sector occurred in the Puna District due to the affordability of residences outside Hilo and the job
opportunities in Hilo.
Table 804-1: Historical Population
1980 1990 2000
1980-90
% Change
1990-2000
% Change
37,559 40,860 44,707 8.8 9.4
Data Source: 2000 U.S. Census
Data redistributed and evaluated for Northeast Mauna Loa Aquifer Sector Area
Table 804-2: Population Projection
Growth
Rate 2000 2005 2010 2015 2020
2000-10
% Change
2010-20
% Change
A – Low 44,707 44,341 45,995 47,699 49,622 2.9 7.9
B – Medium 44,707 44,483 46,401 48,402 50,614 3.8 9.1
C – High 44,707 46,339 49,311 52,203 55,171 10.3 11.9
Data Source: County General Plan, February 2005
Data redistributed and evaluated for Northeast Mauna Loa Aquifer Sector Area
804.1.3 Land Use
804.1.3.1 Hawaii County General Plan
The Hawaii County General Plan Land Use Pattern Allocation Guide Map (LUPAG) for the
Northeast Mauna Loa ASEA is shown on Figure 804-1. The estimated land use allocation
acreage for each LUPAG designation within the sector area is listed in Table 804-3.
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Table 804-3: LUPAG Map Estimated Land Use Allocation Acreage – Northeast Mauna
Loa Aquifer Sector Area
LAND USE PATTERN ACREAGE
% of
TOTAL
High Density Urban 850 0.3
Medium Density Urban 1,396 0.6
Low Density Urban 9,350 3.7
Industrial 4,836 1.9
Important Agricultural Land 17,591 7.1
Extensive Agriculture 26,241 10.5
Orchard 0 0
Rural 3,377 1.4
Resort/Resort Node 77 0.0
Open 1,364 0.6
Conservation 178,453 71.6
Urban Expansion 4,922 2.0
University Use 667 0.3
TOTAL 249,124 100.0
The water utility courses of action for South Hilo and Puna in the Hawaii County General Plan
relevant to the Northeast Mauna Loa ASEA are as follows:
(a) Continue to implement water system maintenance and improvement programs in order to
provide the city with a dependable and consistently safe drinking water supply.
(b) Investigate groundwater sources in the Upper Waiakea Uka area.
(c) Further investigate future groundwater sources.
(d) Investigate additional groundwater sources in the Olaa area.
804.1.3.2 Hawaii County Zoning
Hawaii County Zoning for the Northeast Mauna Loa ASEA is shown on Figure 804-2. The
estimated land use allocation acreage for each zoning class within the Northeast Mauna Loa
ASEA is listed in Table 804-4.
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Table 804-4: County Zoning Estimated Class Allocation Acreage – Northeast Mauna Loa
Aquifer Sector Area
ZONING CLASS ACREAGE % of TOTAL
Single Family Residential 5,635 2.3
Multi-Family Residential
(including duplex) 278 0.1
Residential-Commercial Mixed Use 0 0.0
Resort 125 0.1
Commercial 456 0.2
Industrial 2,662 1.1
Industrial-Commercial Mixed 56 0.0
Family Agriculture 48 0.0
Residential Agriculture 473 0.2
Agriculture 57,992 23.3
Open 6,839 2.7
Project District 0 0.0
Forest Reserve 171,792 68.9
(pond) 45 0.0
(river) 11 0.0
(road) 2,730 1.1
TOTAL 249,142 100.0
804.2 EXISTING WATER RESOURCES
804.2.1 Ground Water
Northeast Mauna Loa ASEA has a sustainable yield of 740 mgd. According to the CWRM
database, there are 41 production wells in the sector area, including 15 municipal, 1 irrigation, 19
industrial, 5 other, and 1 domestic. There are also 16 wells drilled and categorized as “unused.”
Refer to Appendix B for this database. Figure 804-3 shows the well locations.
804.2.2 Surface Water
There are 3 streams classified as perennial in the Northeast Mauna Loa ASEA, the Wailuku
River, the Wailoa River, and the Kaahakini Stream. The USGS has 3 active surface water gages
in the sector area, which were listed in Table 1-8. Two of the gages are on the Waiakea Stream,
which flows into the Wailoa River.
There are 10 declared stream diversions in CRWM database listed in Table 804-5 and shown on
Figure 804-4. The only two diversions with declared flows are those owned by DWS.
804 Northeast Mauna Loa Aquifer Sector Area
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Figure 804-3 Well and Tunnel Location
MAP CURRENTLY NOT AVAILABLE ON-LINE
804 Northeast Mauna Loa Aquifer Sector Area
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Figure 804-4 Streams & Diversions
MAP CURRENTLY NOT AVAILABLE ON-LINE
804 Northeast Mauna Loa Aquifer Sector Area
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Table 804-5: Stream Diversions – Northeast Mauna Loa Aquifer Sector Area
FILE REFERENCE TMK STREAM NAME
CALDWELL P 2-3-015:010 Waiuku River Stream diversion, pipe from Waikapu Stream.
HAWAII ELEC LT 2-3-027:003 Wailuku River
Stream diversion, Puueo Hydro Intake. Declared Q was
estimated by the declarant from the number of kilowatt hours
produced.
HAWAII DWS 2-5-009:012 Kahoama Stream diversion, pipe from Kahoama Stream. Declared Q =
4.6 MGD.
MAKANUI C 2-5-014:042 Unnamed Spring Spring div, trench from Unnamed spring.
WENKO ENERGY 2-5-024:016 Unnamed/ Unmapped
Stream diversion for hydro plant, ditch at upper end of
property takes water from Ainako Stream, flows to Hydro
plant on property and returns water to stream at the lower
end of the property.
OKINO PAE 2-5-025:003 Unnamed/ Unmapped
Stream diversion, channel though yard and back to stream.
Diversion is a small inlet from the stream to the garden.
Water returns to the stream a short distance downstream at
edge of parcel.
HAWAII ELEC LT 2-6-009:025 Wailuku River
Stream diversion, Waiau Hydro Intake. Declared Q was
estimated by the declarant from the number of kilowatt hours
produced.
HAWAII DWS 2-6-018:004 Hookelekele Stream diversion, pipe from Hookelekele Stream. Declared
Q = maximum of 5.0 MGD.
MALU AINA FARM 1-7-002:002 Unnamed/ Unmapped Stream diversion, Waterway #2 through parcel (new entry).
MALU AINA FARM 1-7-002:002 Unnamed/ Unmapped Stream diversion, Waterway #3 through parcel (new entry).
804.2.3 Reclaimed Wastewater
There are no wastewater reclamation facilities within the Northeast Mauna Loa ASEA.
804.3 EXISTING WATER USE
804.3.1 General
The total estimated average water use within the Northeast Mauna Loa ASEA from November
2004 through October 2005 based on DWS meter data, available GIS data, estimates from the
2003 SWPP, and CWRM pumpage data is listed in Table 804-6 and summarized in Figure 804-
5 in accordance with CWRM categories and indicate the quantities supplied excluding
agricultural demands, and the quantities supplied including worst case agricultural demands (as
described in Chapter 2) by the DWS system and non-DWS systems. The quantity listed under
the “Industrial (recharge)” category represents brackish groundwater drawn at the HELCO Hill
and Puna Plants and recharged back to the aquifer by injection. This quantity is not counted
towards the existing or projected water use.
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Table 804-6: Existing Water Use by Categories – Northeast Mauna Loa Aquifer Sector
Area
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.41 6.4 4.9
Industrial 0.00 0.0 0.0
Industrial (recharge) 44.95 N/A N/A
Irrigation 0.00 0.0 0.0
Reclaimed WW 0.00 0.0 0.0
Agriculture 1.87 0.0 22.6
Military 0.00 0.0 0.0
Municipal
DWS System 5.96 93.0 72.0
Private Public WS 0.04 0.6 0.4
Total without Ag* 6.41 100.0
Total with Ag* 8.27 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 804-5: Existing Water Use by Categories – Northeast Mauna Loa Aquifer Sector
Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 804-6 generally shows the service area for the various water systems and indicates the
extent of the DWS water system.
w/o Agricultural Water Use*with Agricultural Water Use*
Domestic 6.4%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 0.6%
Municipal
(DWS) 93.0%
Domestic 4.9%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 22.6%
Military 0.0%
Municipal
(Non-DWS) 0.4%
Municipal
(DWS) 72.0%
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804.3.2 Domestic Use
Domestic use or water use by individual households is assumed to be supplied by private
individual rainwater catchment systems or private wells. Based on available GIS data, there are
over 1,000 such developed parcels, which is approximately 2,800 people, or 6 percent of the
sector area population. The estimated demand is 0.41 mgd. The single well classified as
“Domestic” in the CWRM database does not report pumpage.
804.3.3 Industrial Use
HELCO has seven wells for use at their Hill power generation plant south of Hilo International
Airport. Two wells reported to the CWRM a pumpage of 36.7 mgd for use in the Hill 5 and Hill
6 steam turbines. HELCO also has three wells dedicated to the Puna Generating Plant in Keeau
used for cooling. One well reported a pumpage of 8.3 mgd. Because the extracted water for
both plants is returned to the aquifer via injection wells, the pumpage from these wells were not
included in the existing and 20-year projected demand. HELCO has three Shipman wells that
extract saltwater for cooling, and possesses an NPDES permit to pump the water back into
Suisan Harbor.
Jas Glover Limited owns two wells categorized as “Industrial” in the CWRM database for use at
the Glover Quarry; however, pumpage has not been reported.
There are three hydropower plants located on the Wailuku River northeast of Hilo. HELCO’s
Waiau and Puueo plants each utilize a single stream diversion to power their 2 turbines. The
Wailuku River Hydroelectric Power Company sells to HELCO power generated at their 11 MW
facility located at the junction of the Wailuku River and the Kaloheahewa Stream. Wenko
Energy Company utilizes a stream diversion on the Ainako Stream, a tributary to the Wailuku
River, for its hydropower plant and also sells power to HELCO.
804.3.4 Irrigation Use
There are two golf courses in the sector area, the Hilo Municipal Golf Course and the Naniloa
Country Club. Both courses are within the service area of DWS Hilo Water System. Irrigation
systems are not necessary due to the ample rainfall in the region. Fire trucks are used in the
unlikely event of a drought. There are no known irrigation uses dedicated to other landscaping
activities.
804.3.5 Agricultural Use
There is no flow data available on Agricultural use within the sector area. The abundance of
rainfall in the sector provides sufficient moisture for most crops. There is a small amount drawn
from the DWS Hilo Water System from accounts classified as “Agricultural”.
Malu Aina Farm is a 22-acre spiritual retreat also engaging in organic farming and aquaculture,
located southwest of Kurtistown on the border of the Northeast Mauna Loa and the Kilauea
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ASEAs. According to the CWRM database, the farm has three stream diversions, two of which
are in the sector area, and listed previously in Table 804-5. The farm grows a wide variety of
fruits and vegetables.
804.3.6 Military Use
There is no military use in the Northeast Mauna Loa ASEA.
804.3.7 Municipal Use
Municipal use can be subcategorized into the other water use categories, namely Domestic,
Industrial, Irrigation, Agriculture, and Military, if detailed information is available.
804.3.7.1 County Water Systems
The DWS has 2 water systems in the Northeast Mauna Loa ASEA.
The Hilo Water System is the largest on the island, serving all of urban Hilo and surrounding
areas, extending north to Honolii, south to Panaewa, and west to Kaumana City and Waiakea
Homesteads. Seven deep well sources are utilized. These include three Piihouna Wells along
Waianuenue Ave, and three Panaewa Wells off of Hawaii Belt Highway. The Piihonuna Wells
service the northern portion of the system, while the Panaewa Wells service the southern portion.
The Saddle Road A Well servicing the Panaewa area became operational in 2002. The system
was formerly supplied by several spring and surface water sources that are no longer in service,
including the Waiakea-Uka Tunnels, Olaa Flume Spring, Lyman Spring, Kaohama Intake,
Pukamaui Intake and Lauole Intake. The Hilo WS also supplements the adjacent Papaikou
system.
The Olaa-Mt. View Water System is located in the Puna District along Hawaii Belt Road from
Keeau to the Olaa Reservation Lots, and along Keeau-Pahoa Road, servicing areas in the Kilauea
ASEA. The system’s sources are two deep Keeau Wells at the former Puna Sugar Mill, and one
deep well, Olaa 3, further south along Hawaii Belt Road. Water is pumped through a series of
eight booster pump stations and storage tanks spanning 11 service areas.
DWS water use is subcategorized in Table 804-7 to the extent possible based on available meter
data and is depicted in Figure 804-7. “Other Municipal” includes facilities such as schools, and
various commercial, government, medical and nonprofit entities which have mixed water use and
cannot be specifically allocated to the other categories.
804 Northeast Mauna Loa Aquifer Sector Area
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Table 804-7: DWS Existing Water Use by Categories – Northeast Mauna Loa Aquifer
Sector Area
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 3.75 62.9
Industrial 0.00 0.0
Irrigation 0.00 0.0
Agriculture 0.27 4.5
Military 0.00 0.0
Other Municipal 1.94 32.6
Total 5.96 100.0
Figure 804-7: DWS Existing Water Use by Categories – Northeast Mauna Loa Aquifer
Sector Area
Domestic 62.9%
Industrial 0.0%
Irrigation 0.0%
Agriculture 4.5%
Military 0.0%
Other Municipal
32.6%
804.3.7.2 State Water Systems
The Kulani Correctional System is owned by the Department of Public Safety (DPS). It is
located in Kulani, off Stainback Highway. The source of water is a rubber lined sloped
catchment area covering approximately 5 acres. The water is stored in an open rubber lined 5.0
mgd reservoir and treated with a packaged treatment plant. The distribution system includes a
0.36 MG steel storage tank and 12-inch and 8-inch watermains, serving the camp facilities which
include dormitories, administration building, kitchen, mess hall, laundry boiler, saw mill, garage,
804 Northeast Mauna Loa Aquifer Sector Area
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gym, lumber shed, woodwork shop, program building and craft display. The estimated
consumption according to the SWPP based on an inmate population of 217 and a staff of 85 is
0.037 mgd, with a maximum day demand of 0.06 mgd.
804.3.7.3 Federal Water Systems
There are no Federal water systems in the Northeast Mauna Loa ASEA regulated by the DOH.
804.3.7.4 Private Public Water Systems
The Mauna Loa Macadamia Nut Water System is the only private public water system in the
sector area regulated by the DOH. The water system is located on a 114-acre parcel of land
southeast of Hilo, which has a visitor center, processing plant, snack bar and gift shop. There is
also a “nature walk” showcasing the trees and plants that produce various fruits and vegetables.
The primary well source has a pumping capacity of 350 gpm and the secondary source has a
capacity of 500 gpm. The system is disinfected with sodium chloride and utilizes a 5,000 gallon
hydropneumatic tank. DOH records indicate that there are 4 service connections serving a
population of 100. The wells did not report pumpage to the CWRM.
804.3.8 Water Use by Resource
804.3.8.1 Ground Water
Table 804-8 summarizes the current production, potential production (16 and 24-hour
operation), sustainable yield (SY), and percentage of SY for the various productions calculated.
Current production is represented by the highest 12-month moving average (MAV) or the
highest annual average yield calculated from the actual pumpage data. Potential well production
is based on installed pump capacities, and calculated for both 16 hours of operation a day and 24
hours of operation a day. Data is based on pumpage data reported to CWRM.
Table 804-8: Sustainable Yield – Northeast Mauna Loa Aquifer Sector Area
Sys Code System Area
High
12-Month
MAV
(MGD)
Potential
16 -Hour
Production
(MGD)
Potential
24-Hour
Production
(MGD) SY (MGD)
High
12-Month
MAV
SY
(%)
Potential
16-Hour
Production
SY
(%)
Potential
24-Hour
Production
SY
(%)
59.05 62.95 94.43 740 7.98 8.51 12.76
80401 Hilo 42.78 42.15 63.22 347 12.33 12.15 18.22
80402 Keeau 16.27 20.81 31.21 393 4.14 5.29 7.94
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804.3.8.2 Surface Water
Malu Aina Farm described in Section 804.3.5 uses two stream diversions, however flow data is
not available.
804.3.8.3 Rainwater Catchment
Water consumption calculated for developed parcels that are not supplied by groundwater or
surface water is assumed to be supplied by rainwater catchment. The water use categorized as
Domestic Use previously in Table 804-6 is assumed to be supplied by individual catchment
systems.
Kulani Correctional Facility described previously in Section 804.3.7.2 utilizes a rainwater
catchment system. According to the 2003 SWPP, the design capacity is 0.024 mgd, which does
not meet the estimated demand.
The Malu Aina Farm uses rainwater catchment tanks for its potable water supply, however
consumption data is not readily available.
804.3.8.4 Reclaimed Wastewater
There are no wastewater reclamation facilities within the Northeast Mauna Loa ASEA.
804.4 FUTURE WATER NEEDS
804.4.1 General
Table 804-9 summarizes the LUPAG, Zoning and 5-year incremental water demand projection
scenarios for the total aquifer sector area and the individual aquifer system areas. The
sustainable yield (SY) is presented to draw comparisons.
Table 804-9: Summary of Demand Projections
Growth Rate B Demand Projections (mgd)Without
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total N.W. Mauna Loa ASEA 740 118.6 26.3 6.4 6.7 7.0 7.3 7.7
80401 – Hilo ASYA 347 69.2 21.9 4.7 4.8 4.9 5.0 5.2
80402 – Keeau ASYA 393 49.4 4.4 1.7 1.9 2.1 2.3 2.5
Growth Rate B Demand Projections (mgd)With
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total N.W. Mauna Loa ASEA 740 202.6 107.4 8.3 8.7 9.2 9.8 10.4
80401 – Hilo ASYA 347 70.7 28.0 4.7 4.8 4.9 5.1 5.2
80402 – Keeau ASYA 393 132.0 79.4 3.6 3.9 4.3 4.7 5.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
804 Northeast Mauna Loa Aquifer Sector Area
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For both aquifer system areas, full build-out and 2025 projection water demands excluding
agricultural demands are a small fraction the SY. Therefore, analysis of the three demand
scenarios does not need to be broken down by aquifer system areas and thus will be presented for
the aquifer sector area only.
804.4.2 Full Build-Out Water Demand Projections
The full build-out water demand projections based on the General Plan and County Zoning for
the Northeast Mauna Loa ASEA are listed in Tables 804-10 and 804-11, and reflect refinement
as discussed below. Each land use class is associated with the most appropriate CWRM water
use category.
Table 804-10: Hawaii County General Plan Full Build-Out Water Demand Projection –
Northeast Mauna Loa Aquifer Sector Area
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 64.7
Urban Expansion Domestic/Irrigation/Municipal 29.6
Resort Irrigation/Municipal 1.3
Industrial Industrial 17.0
Agriculture Agriculture 84.0
University Irrigation/Municipal 2.7
Rural Irrigation/Municipal 1.4
DHHL Irrigation/Municipal 2.0
TOTAL w/o Ag* 118.6
TOTAL w/ Ag* 202.6
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 804-11: County Zoning Full Build-Out Water Demand Projection – Northeast
Mauna Loa Aquifer Sector Area
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 11.0
Resort Irrigation/Municipal 2.9
Commercial Municipal 1.0
Industrial Industrial 9.4
Agriculture Agriculture 81.2
DHHL Irrigation/Municipal 2.0
TOTAL w/o Ag* 26.3
TOTAL w/ Ag* 107.4
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
804 Northeast Mauna Loa Aquifer Sector Area
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804.4.2.1 Refine Land Use Based Projection
804.4.2.1.1 State Water Projects Plan
The total projected demand to the year 2020 for 46 State Water Projects within the sector area is
4.60 mgd, using 0.86 mgd potable, 3.69 mgd nonpotable, and 0.05 nonpotable using potable
sources. These demands may account for approximately 30 percent of the total water demand in
the sector area. The projects that will generate the most significant demands, with the exception
of DHHL projects, which are covered separately, are listed in Table 804-12. Projects with large
demands greater than 1 mgd may require State funding to develop resources and infrastructure
necessary to provide water service.
Table 804-12: Future State Water Projects to Generate Significant Demands
Project Name
Primary Use
State
Department
2020 Demand
(mgd)
Pacific Aquaculture and Coastal
Resources Center Nonpotable
University of
Hawaii 1.65
Pacific Aquaculture and Coastal
Resources Center, UHH Farm @ Panaewa Nonpotable
University of
Hawaii 0.75
Panaewa Farm Well and Pump Nonpotable
University of
Hawaii 0.35
804.4.2.1.2 State Department of Hawaiian Home Lands
The Keaukaha-Waiakea-Panaewa Tracts are located in urban Hilo between Hilo Bay and the
Puna boundary. The Keaukaha Tract is a mostly vacant 1,700-acre area divided into two tracts
along the northeast coast of Hilo Bay. The Waiakea-Panaewa Tract is south of Hilo airport with
existing residential and farm lots. New post-1994 land transfers include the Old Airport
Terminal, the National Guard Tract and the Puna Boundary lots. The proposed land uses are a
combination of residential, agricultural and industrial uses. The total estimated demand for the
tracts is 2.01 mgd, which would be supplied by the DWS Hilo Water System. The DHHL
Special Report #2 indicates that the Hilo WS may currently have sufficient supply to meet part of
the proposed water requirements; however, full build-out would require additional supply source
to supplement the present capacity of the system.
The Hilo Scattered Lots are comprised of 83 scattered lots throughout urban Hilo. 56 lots were
transferred from the State in 1994, some of which were subdivided. Water service from the Hilo
Water System was already in place for most of the lots. 81 of the 83 lots are proposed for
residential use, with an estimated demand of 0.04 mgd.
804.4.2.1.3 Agricultural Water Use and Development Plan
There is no information available in the AWUDP specific to activity within the sector area to
further refine projections.
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804.4.3 Water Use Unit Rates
Water use unit rates are based on the Water System Standards as discussed in Chapter 1.
804.4.4 5-Year Incremental Water Demand Projection to the Year 2025
The following section presents 5-year incremental water demand projections to the year 2025 for
the Northeast Mauna Loa ASEA. The projected low, medium, and high growth rates are listed in
Table 804-13, and are graphed in Figure 804-8. Potable and nonpotable water demands are also
differentiated.
Figure 804-9 illustrates the magnitude of the sustainable yield, both LUPAG and Zoning full
build-out water use, and water use projection through the year 2025 focusing on Medium Growth
Rate B. Figure 804-10 shows the breakdown of water demand projections by CWRM categories
through the year 2025. Table 804-14 summarizes these figures.
Table 804-13: Water Demand Projection – Northeast Mauna Loa Aquifer Sector Area
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 6.4 6.7 6.9 7.2 7.5 8.3 8.7 9.1 9.6 10.2
Potable 6.4 6.7 6.9 7.2 7.5 6.4 6.7 6.9 7.2 7.5
Nonpotable 0.0 0.0 0.0 0.0 0.0 1.9 2.0 2.2 2.4 2.7
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 6.4 6.7 7.0 7.3 7.7 8.3 8.7 9.2 9.8 10.4
Potable 6.4 6.7 7.0 7.3 7.7 6.4 6.7 7.0 7.3 7.7
Nonpotable 0.0 0.0 0.0 0.0 0.0 1.9 2.0 2.2 2.5 2.7
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 6.4 6.8 7.2 7.7 8.1 8.3 8.9 9.5 10.2 11.0
Potable 6.4 6.8 7.2 7.7 8.1 6.4 6.8 7.2 7.7 8.1
Nonpotable 0.0 0.0 0.0 0.0 0.0 1.9 2.1 2.3 2.6 2.9
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
804 Northeast Mauna Loa Aquifer Sector Area
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Figure 804-8: Water Demand Projection Summary – Northeast Mauna Loa Aquifer Sector
Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 804-14: Medium Growth Rate B Water Demand Projection by Category – Northeast
Mauna Loa Aquifer Sector Area
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 6.4 6.7 7.0 7.3 7.7
Total with Ag* 8.3 8.7 9.2 9.8 10.4
Domestic 0.4 0.4 0.5 0.5 0.5
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 0.0 0.0 0.0 0.0 0.0
Agriculture 1.9 2.0 2.2 2.5 2.7
Military 0.0 0.0 0.0 0.0 0.0
Municipal 6.0 6.3 6.5 6.8 7.2
Potable 6.4 6.7 7.0 7.3 7.7
Nonpotable w/o Ag* 0.0 0.0 0.0 0.0 0.0
Nonpotable w/ Ag* 1.9 2.0 2.2 2.5 2.7
DWS 6.0 6.2 6.5 6.8 7.1
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
2.0
4.0
6.0
8.0
10.0
12.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
5.0
10.0
15.0
20.0
25.0
2005 2010 2015 2020 2025
YearDemand (mgd)Potable
Total w/o Ag*
Non-Potable w/o Ag*
Total w/ Ag*
Potable
LEGEND: Growth Rate A Growth Rate B Growth Rate C
Non-Potable w/ Ag*
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Figure 804-9: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Northeast Mauna Loa Aquifer Sector Area
0
100
200
300
400
500
600
700
800
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 740
LUPAG = 119–203
Zoning = 26–107
Legend*,**
Addendum No. 1, 2/3/2012
804 Northeast Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Figure 804-10: Medium Growth Rate B Water Demand Projection by Category –
Northeast Mauna Loa Aquifer Sector Area
0.0
2.0
4.0
6.0
8.0
10.0
12.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
804.4.5 DWS Historical Water Consumption Data Projections
DWS supplied water consumption was projected in 5-year increments to the year 2025 based on
DWS historical water system consumption data from 1970 to 2003, as shown on Figure 804-11.
Legend*, **
804 Northeast Mauna Loa Aquifer Sector Area
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Figure 804-11: DWS Water Demand Projection – Northeast Mauna Loa Aquifer Sector
Area
Hilo Water System
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
1970 1980 1990 2000 2010 2020mgdHistorical Projected
Year 2005: 6.24 mgd
Year 2010: 6.56 mgd
Year 2015: 6.88 mgd
Year 2020: 7.20 mgd
Year 2025: 7.51 mgd
Historical data provided by RW Beck, Inc.
Projections based on historical DWS water consumption data cannot be compared to projections
based on population growth rate, because the latter includes part of the Mt. View-Olaa Water
System. However, the rate of increase of the two projections is very close. DWS may need to
supply potable water equivalent to as much as half of the total projected water supply for the
sector area.
804 Northeast Mauna Loa Aquifer Sector Area
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804.5 RESOURCE AND FACILITY RECOMMENDATIONS
804.5.1 Water Source Adequacy
804.5.1.1 Full Build-Out
Full development to the maximum density of the County General Plan and Zoning land use
within the Northeast Mauna Loa Aquifer Sector Area (ASEA) can be sustained by conventional
water resources. If agricultural demands are excluded, LUPAG water demands are
approximately 15 percent of the sustainable yield (SY) of the sector area, and existing zoning
requires approximately 3 percent of the SY. Including worst case agricultural demands, the
LUPAG demand is 27 percent of the SY, and the Zoning demand is 14 percent of the SY.
804.5.1.2 Twenty-Year Projection
20-year projected water demands are approximately 1 percent of the sector area SY.
804.5.2 Source Development Requirements
804.5.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, are evaluated to meet projected water demands.
804.5.2.1.1 Conventional Water Resource Measures
804.5.2.1.1.1 Ground Water
At 740 mgd, the Northeast Mauna Loa ASEA has the highest sustainable yield of all aquifer
sector areas on the island. According to the 1990 WRPP, it is reflective of the high annual
rainfall and the infiltrability of the surface rocks. Basal water occurs several miles inland,
followed by high level dike and perched water. Both sources are available in great quantities.
DWS recently commissioned the Saddle Road A Well, which encountered water at an elevation
of nearly 1,000 feet. Whether high level or basal sources are developed will depend on the
location of future development.
The usage of nonpotable groundwater for industrial purposes at the power plants may increase if
expansions to the facilities are warranted. Because most of the water drawn for industrial
purposes is returned to the aquifer, it is expected that such increased usage will not adversely
affect the aquifer; however, it would be prudent to confirm the effects of recharge.
804.5.2.1.1.2 Surface Water
804 Northeast Mauna Loa Aquifer Sector Area
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As mentioned previously, there are several surface water sources in the sector area formerly used
by DWS. New sources are not likely to be developed since groundwater is far more abundant
and is less costly to develop due to the requirements for treatment and monitoring of surface
water, making groundwater the preferred source. Abandoned surface water sources may be
reactivated to meet localized nonpotable demands.
804.5.2.1.1.3 Water Transfer
Water transfer is already taking place; the Hilo Water System (WS) supplements the Papaikou
Water System in the East Mauna Kea ASEA (802). The transfer of water is borne out of
economics due to the magnitude of the Hilo WS, which can easily supplement the much smaller
Papaikou WS, not because of lack of available sources in ASEA 802 in the vicinity of the
Papaikou WS. Since both sector areas have ample source water, the effect of the transfer is
miniscule.
804.5.2.1.2 Alternative Water Resource Enhancement Measures
804.5.2.1.2.1 Rainwater Catchment Systems
Except for the uninhabited areas towards the summit of Mauna Loa, all areas within the sector
area receive enough rainfall to support rainwater catchment systems. A small percentage of
domestic users already rely on catchment, and may continue to do so if extension of the
municipal water system is not feasible.
804.5.2.1.2.2 Wastewater Reclamation
The magnitude of the Hilo Water System would lend nicely to a large scale wastewater
reclamation facility. However, a far-reaching nonpotable reclaimed water system would likely
not be implemented due to the availability of other water sources in most of the sector area,
therefore usage would be confined to locations in close proximity. The need for such a facility
would be contingent on development requiring a significant quantity of nonpotable water in the
immediate vicinity that cannot be sustained by the ambient rainfall.
804.5.2.1.2.3 Desalination
According to the CWRM Well Database, chloride contents of existing wells up to 2 miles inland
are no greater than 300 ppm. Facilities for desalination of brackish groundwater would only be
considered along the coast, out of the service area of the municipal water system. Due to the
high cost of desalination, extension of the existing water system is more practical.
804.5.2.2 Demand-Side Management
804.5.2.2.1 Development Density Control
804 Northeast Mauna Loa Aquifer Sector Area
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Full build-out demands associated with LUPAG maximum density are over four times greater
than that of Zoning. This is in part due to higher maximum density unit rates for Urban areas,
and in part due to the significant amount of land designated as “Urban Expansion.” However,
because of the magnitude of the SY compared to the projected demands, development density
control is not considered critical.
804.5.2.2.2 Water Conservation
The average water consumption per connection to the DWS water system in the sector area is
400 gpd, and the average current potable water consumption per capita from all sources is 145
gpd, both of which are exactly the island average. Demand side water conservation should
continue, but further measures are not considered necessary at this point.
The Hilo Water System is the most inefficient water system on the island. Between 2001 and
2003, in the neighborhood of 50 percent of the source water produced was unaccounted for,
which amounts to approximately 5 mgd. Although this is minimal in comparison to the
sustainable yield of the aquifer sector area, significant long-term cost savings could be achieved
by implementing supply-side conservation measures. These measures include meter inspection
and replacement/repair, leak detection and remediation, and non-revenue water analysis.
804.5.3 Recommended Alternatives
Groundwater should continue to be developed as the primary potable water source in locations of
anticipated development. Specifically, as recommended in the General Plan, groundwater
sources should be investigated in the Waiakea Uka and Saddle Road areas.
Careful monitoring of the aquifer should accompany increased nonpotable water usage through
the HELCO Wells should be due to the enormous quantity drawn and returned to the aquifer
through recharge.
DWS should consider supply-side water conservation measures to reduce the unaccounted water
to acceptable levels. The quantity of production water saved would be less than 1 percent of the
sustainable yield; therefore, these measures would be implemented primarily for cost control.
805 Southeast Mauna Loa Aquifer Sector Area
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805 SOUTHEAST MAUNA LOA AQUIFER SECTOR AREA
805.1 SECTOR AREA PROFILE
805.1.1 General
The Southeast Mauna Loa Aquifer Sector Area (ASEA) includes the Olaa [80501], Kapapala
[80502], Naalehu [80503] and Ka Lae [80504] Aquifer System Areas (ASYA). It covers the
south central portion of the island, primarily in the Kau District, and the northwest section of the
Puna District. The boundaries extend from the summit of Mauna Loa to Mountain View in the
east, along Hawaii Belt Highway to Punaluu, and along the southeastern coastline to Ka Lae.
Coastal areas have an average rainfall of 20 to 50 inches per year, while the areas approaching
the summit of Mauna Loa average as little as 15 inches per year. A pocket of heavier average
rainfall of 158 inches per year occurs at approximately 3,000 feet elevation between Naalehu and
Pahala. Annual rainfall in the Mountain View area averages up to 196 inches. The Olaa ASYA
has the highest SY of the four aquifer system areas at 124 mgd, followed by the Naalehu ASYA
at 117 mgd, the Ka Lae ASYA at 31 mgd, and the Kapapala ASYA at 19 mgd. The total
sustainable yield of the sector area is 291 mgd.
805.1.2 Economy and Population
805.1.2.1 Economy
Agriculture remains the anchor of Kau’s economy. A variety of different products are grown
primarily in the strip from Naalehu to Wood Valley, including macadamia nuts, coffee, orchids,
and vegetables. The macadamia nut industry is one of the most prominent in the district,
boasting Mac Farms of Hawaii in Naalehu, the world’s largest macadamia nut tree orchard.
Cattle ranching is also significant, with large tracts of land utilized by several ranches, including
the 1,595-acre Kahuku Ranch north of Puueo.
The main tourist destination is the Sea Mountain Resort and Golf Course Complex.
Accommodations on the resort are limited to the 56-unit Colony One at Sea Mountain. Other
accommodations are scarce, with bed-and-breakfast operations and the 12-unit Shirakawa Hotel
in Waiohinu as the only options.
805.1.2.2 Population
Most of the population contributing to the demands from the sector area is within the Kau
District. Much of the increase in population can be attributed to the growth in small
communities.
805 Southeast Mauna Loa Aquifer Sector Area
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Table 805-1: Historical Population
1980 1990 2000
1980-90
% Change
1990-2000
% Change
3,044 4,048 5,554 33.0 37.2
Data Source: 2000 U.S. Census
Data redistributed and evaluated for Southeast Mauna Loa Aquifer Sector Area
Table 805-2: Population Projection
Growth
Rate 2000 2005 2010 2015 2020
2000-10
% Change
2010-20
% Change
A – Low 5,554 6,222 6,935 7,721 8,613 24.9 24.2
B – Medium 5,554 6,242 6,997 7,835 8,786 26.0 25.6
C – High 5,554 6,502 7,435 8,451 9,577 33.9 28.8
Data Source: County General Plan, February 2005
Data redistributed and evaluated for Southeast Mauna Loa Aquifer Sector Area
805.1.3 Land Use
805.1.3.1 Hawaii County General Plan
The Hawaii County General Plan Land Use Pattern Allocation Guide Map (LUPAG) for the
Southeast Mauna Loa ASEA is shown on Figure 805-1. The estimated land use allocation
acreage for each LUPAG designation within the sector area is listed in Table 805-3.
LEGEND:Hawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-818FUKUNAGA & ASSOCIATES, INC.Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
INDEX MAP - Island of Hawaii
2 0 21
Miles
2005 Revised GeneralPlan Land Use PatternAllocation Guide
Extensive Agriculture
Important Agricultural Land
Orchard
High Density Urban
Medium Density Urban
Low Density Urban
Industrial
Urban Expansion
Resort
Resort Node
Rural
Conservation
Open
University Use
Pond
Break Water
FIGURE 805-1
AQUIFER SECTOR
S.E. MAUNA LOA - 805Aquifer Systems
Developed Properties
Hawaiian Home Lands
Land Use Pattern Allocation Guide
Olaa - 80501Kapapala - 80502Naalehu - 80503Kalae - 80504
Olaa80501
P A C I F I C O C E A N
Naalehu80503
Kapapala80502
Ninole Cove
Honuapo Bay
Waikapuna Bay
Waikapuna Bay
Ninole Cove
Honuapo Bay
Kaalualu Bay
Ka Lae Pt.
Kalae80504
Kalae80504
Naalehu80503
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-5
Hawaii County
Water Use and Development Plan Update
Table 805-3: LUPAG Map Estimated Land Use Allocation Acreage – Southeast Mauna
Loa Aquifer Sector Area
LAND USE PATTERN ACREAGE
% of
TOTAL
High Density Urban 0 0
Medium Density Urban 416 0.1
Low Density Urban 1,247 0.3
Industrial 74 0.0
Important Agricultural Land 49,788 11.2
Extensive Agriculture 109,885 24.8
Orchard 0 0
Rural 3,843 0.9
Resort/Resort Node 29 0.0
Open 2,596 0.6
Pond 0 0
Conservation 274,153 62.0
Urban Expansion 325 0.1
University Use 0 0
TOTAL 442,356 100.0
The water utility courses of action for Kau in the Hawaii County General Plan relevant to the
Southeast Mauna Loa ASEA are as follows:
(a) Provide additional water system improvement for the currently serviced areas of
Naalehu, Waiohinu, and Pahala.
(b) Pursue groundwater source investigation, exploration and well development at Ocean
View, Pahala, and Waiohinu.
(c) Continue to evaluate growth conditions to coordinate improvements as required to the
existing water system.
(d) Investigate alternative means to finance the extension of water systems to subdivisions
that rely on catchment.
805.1.3.2 Hawaii County Zoning
Hawaii County Zoning for the Southeast Mauna Loa ASEA is shown on Figure 805-2. The
estimated land use allocation acreage for each zoning class within the sector area is listed in
Table 805-4.
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-6
Hawaii County
Water Use and Development Plan Update
Table 805-4: County Zoning Estimated Class Allocation Acreage – Southeast Mauna Loa
Aquifer Sector Area
ZONING CLASS ACREAGE % of TOTAL
Single Family Residential 814 0.2
Multi-Family Residential
(including duplex) 105 0.0
Residential-Commercial Mixed Use 0 0
Resort 40 0.0
Commercial 65 0.0
Industrial 55 0.0
Industrial-Commercial Mixed 0 0
Family Agriculture 0 0
Residential Agriculture 0 0
Agriculture 181,764 41.1
Open 132,804 30.0
Project District 0 0
Forest Reserve 125,143 28.3
(pond) 2 0.0
(road) 1,562 0.4
TOTAL 442,354 100.0
805.2 EXISTING WATER RESOURCES
805.2.1 Ground Water
The Southeast Mauna Loa ASEA has a sustainable yield of 291 mgd. According to the CWRM
database, there are 50 production wells in the sector area, including 6 municipal, 38 irrigation,
and 6 industrial. There are also 11 wells drilled and categorized as “unused.” Refer to
Appendix B for this database. Figure 805-3 shows the well locations. In the Pahala and
Naalehu areas, many of the wells are tunnels dug into the hillsides to develop perched
groundwater sources for fluming sugar cane to the old sugar mill.
The 1994 Kau River Basin Study indicates that the yield of all tunnel sources is in the order of 7
to 8 mgd. Several springs and tunnels are mentioned as potential water sources. Ninole Springs
is the second largest basal spring on the island, having an estimated past discharge of 20 to 25
mgd. Kawaa springs was estimated to have a discharge of 10 mgd, however, there are no
indications that either has been developed as a water source. The output of the springs and
tunnel sources are significantly less during the dry season.
805.2.2 Surface Water
There are no streams classified as perennial in the Southeast Mauna Loa ASEA.
LEGEND:Hawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-8182 0 21
Miles
Agricultural - 1 thru 10 acresAgricultural - 20 acresAgricultural - 35 acresAgricultural - 40 acresAgricultural - 80 acresAgricultural - 200 thru 255 acresAgricultural - 500 acresAgricultural - 600 acresAgricultural - 800 acresAgricultural - 900 acresAgricultural Project DistrictsDowntown Hilo Commercial DistrictCommercial, GeneralCommercial, NeighborhoodCommercial, VillageFamily AgriculturalForest ReserseIndustrial - CommercialIndustrial, GeneralIndustrial, LimitedOpenProject DistrictsResidentail and AgriculturalResidential - Commercial Mixed UseResidential Double-FamilyRes. Multi-Family - 7500-8000 sfRes. Multi-Family - 14,500-20,000 sfRes. Single Family - 7500-10,000 sfRes. Single Family - 15,000-20,000 sfHotel/Resort
Zoning Designations:
A-1a+A-20aA-35aA-40aA-80aA-200+A-500aA-600aA-800aA-900aAPDCDHCGCNCVFAFRMCXMGMLOPDRARCXRDRM-7.5+RM-14.5+RS-7.5+RS-15+V
Developed ParcelsHawaiian Home Lands
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
INDEX MAP - Island of Hawaii
County Zoning
FIGURE 805-2
AQUIFER SECTORS.E. MAUNA LOA - 805Aquifer SystemsOlaa - 80501Kapapala - 80502Naalehu - 80503Kalae - 80504
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-9
Hawaii County
Water Use and Development Plan Update
Figure 805-3: Well and Tunnel Location
MAP CURRENTLY NOT AVAILABLE ON-LINE
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-11
Hawaii County
Water Use and Development Plan Update
Figure 805-4: Streams & Diversions
MAP CURRENTLY NOT AVAILABLE ON-LINE
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-13
Hawaii County
Water Use and Development Plan Update
There are 9 declared stream diversions in CRWM database listed in Table 805-5 and shown on
Figure 805-4. Flow data is not available for these diversions.
Table 805-5: Stream Diversions – Southeast Mauna Loa Aquifer Sector Area
FILE REFERENCE TMK STREAM NAME
KAU INSTREAM 9-5-014:007 Honuapo Pond Spring diversion, hand carry Honuapo Spring Pond and
rights claim.
KAU INSTREAM 9-5-016:006 Kawa Springs Spring diversion, hand carry from Kaalaiki Pond and rights
claim.
KAU INSTREAM 9-5-019:012 Ninole Fishpond
Spring diversion, hand carry from Kauwale Pond. Diversion
at spring-fed smaller (northern) portion of fishpond. Rights
claim.
KAU INSTREAM 9-5-019:012 Ninole Fishpond Spring diversion, hand carry from Puhau Pond. Diversion at
spring-fed main (makai) portion of fishpond. Rights claim.
KAU INSTREAM 9-6-001:003 Kauwila Pond Spring diversion, hand carry from Kauwila Pond and rights
claim.
KAWAIHAE RANCH 9-7-001:001 Haao Spring Spring diversion, use of overflow from County Haao Spring
when available.
KAPAPALA USERS 9-7-001:006 Alili Spring Stream diversion, hand carry from Alili Kapapala Spring and
rights claim.
KAWAIHAE RANCH 9-7-001:020 Mountain House Spring Spring diversion, use of overflow from County Mountain
House Spring.
KAU INSTREAM 9-3-001:003 Palehemo Pond Spring diversion, hand carry from Palehemo Stream and
rights claim.
The Kau Flume System transports perched groundwater from the two Noguchi Tunnels to the
Keaiwa Reservoir north of Pahala. A 2000 study completed by the US Army Corps of Engineers
estimated the yield of the tunnels between 0.2 and 0.6 mgd, depending on rainfall. At the time of
the study, two additional inflows along the flume were not functioning, and the system was in
need of major repairs.
805.2.3 Reclaimed Wastewater
There is one wastewater reclamation facility (WWRF) in the study area. Table 805-6 lists the
WWRF, reclaimed water classification, facility treatment capacity, current reuse amount, and
current application.
Table 805-6: Wastewater Reclamation Facilities – Southeast Mauna Loa Aquifer Sector
Area
Wastewater
Reclamation Facility
Reclaimed
Water
Classification
WWRF
Capacity
(MGD)
Current
Reuse
Amount
(MGD)
Irrigation Application
Punaluu Water &
Sewer R-2 0.125 0.012 Sea Mountain Golf Course
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-14
Hawaii County
Water Use and Development Plan Update
805.3 EXISTING WATER USE
805.3.1 General
The total estimated average water use within the Southeast Mauna Loa ASEA based on DWS
meter data and CWRM pumpage data from November 2004 through October 2005, available
GIS information, DOH records, and estimated reclaimed wastewater usage is listed in Table
805-7. Table 805-7 and Figure 805-5 summarize water use in accordance with CWRM
categories and indicate the quantities supplied excluding agricultural demands, and the quantities
supplied including worst case agricultural demands (as described in Chapter 2) by the DWS
system, non-DWS systems, and reclaimed wastewater.
Table 805-7: Existing Water Use by Categories – Southeast Mauna Loa Aquifer Sector
Area
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.33 27.7 6.9
Industrial 0.00 0.0 0.0
Irrigation 0.26 21.7 5.4
Reclaimed WW 0.01 1.0 0.3
Agriculture 3.58 0.0 75.2
Military 0.00 0.0 0.0
Municipal
DWS System 0.57 47.9 11.9
Private Public WS 0.02 1.7 0.4
Total without Ag* 1.18 100.0
Total with Ag* 4.77 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-15
Hawaii County
Water Use and Development Plan Update
Figure 805-5: Existing Water Use by Categories – Southeast Mauna Loa Aquifer Sector
Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 805-6 generally shows the service area for the various water systems and indicates the
extent of the DWS water system.
805.3.2 Domestic Use
Domestic use or water use by individual households is assumed to be supplied by private
individual rainwater catchment systems. Based on available GIS data, there are 820 such units
serving approximately 2,250 people, which is approximately one-third of the sector’s population.
The estimated demand is 0.33 mgd.
805.3.3 Industrial Use
There are three tunnels and one shaft classified as “Industrial” in the CWRM database. None
have reported pumpage.
805.3.4 Irrigation Use
The Sea Mountain Resort in Punaluu utilizes two sources for its golf course. 0.257 mgd is
supplied by the private Punaluu Water System described below in Section 805.3.7.4, augmented
with 0.012 mgd of reclaimed wastewater from the Punaluu Sewage Treatment Plant.
Domestic 27.7%
Industrial 0.0%
Irrigation 21.7%
Irrigation (Recl'd
WW) 1.0%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 1.7%
Municipal
(DWS) 47.9%
Domestic 6.9%
Industrial 0.0%
Irrigation 5.4%
Irrigation (Recl'd
WW) 0.3%
Agriculture 75.2%
Military 0.0%
Municipal
(Non-DWS) 0.4%
Municipal
(DWS) 11.9%
w/o Agricultural Water Use*with Agricultural Water Use*
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-16
Hawaii County
Water Use and Development Plan Update
The Discovery Harbor Golf Course is located within the service area of the DWS Naalehu-
Waiohinu Water System; however, usage is not known. There are no known irrigation uses
dedicated other landscaping activities in the sector area.
Many of the wells in the CWRM database classified as “Irrigation” are tunnels or shafts that
were used by the sugar plantation to transport sugar by flume to the sugar mill.
805.3.5 Agricultural Use
Over 20 percent of the metered water drawn from the DWS water system is from accounts
classified as “Agricultural;” however, this amounts to only 0.12 mgd.
The Kau River Basin Study indicates that some of the water from the Noguchi Tunnels, described
previously, is diverted for agricultural uses in Wood Valley. The rest of the water flows to the
Keaiwa Reservoir, which supplies the Keaiwa Agricultural Park. The study suggests that there is
a significant amount of water currently used for agricultural purposes, however current flow data
is not readily available.
805.3.6 Military Use
There is no military use in the Southeast Mauna Loa ASEA.
805.3.7 Municipal Use
Municipal use can be subcategorized into the other water use categories, namely Domestic,
Industrial, Irrigation, Agriculture, and Military, if detailed information is available.
805.3.7.1 County Water Systems
The DWS has 2 water systems in the Southeast Mauna Loa ASEA.
The Pahala Water System relies on the Alili Tunnel for its supply and supplements it with water
from the Pahala Well during dry weather. The system has a relatively compact service area in
Pahala Village. The Pahala Deep Well No. 2 was drilled in 2003, but it is currently sealed and
there is no evidence of usage.
The Waiohinu-Naalehu Water System was assumed by DWS after the closure of the sugar
plantation. The system primarily depends on the New Mountain House Tunnel Spring and Haao
Spring for its supply. The Naalehu Well supplements the tunnel and spring sources during dry
weather. The service area is widespread, covering the communities of Waiohinu, Naalehu and
South Point, spanning six service zones through two booster pump stations and nine storage
tanks.
DWS water use is subcategorized in Table 805-8 to the extent possible based on available meter
data and is depicted in Figure 805-7. “Other Municipal” includes facilities such as schools, and
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-19
Hawaii County
Water Use and Development Plan Update
various commercial, government, medical and nonprofit entities which have mixed water use and
cannot be specifically allocated to the other categories.
Table 805-8: DWS Existing Water Use by Categories – Southeast Mauna Loa Aquifer
Sector Area
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 0.37 65.5
Industrial 0.00 0.0
Irrigation 0.00 0.0
Agriculture 0.12 21.3
Military 0.00 0.0
Other Municipal 0.07 13.1
Total 0.57 100.0
Figure 805-7: DWS Existing Water Use by Categories – Southeast Mauna Loa Aquifer
Sector Area
Domestic 65.5%
Industrial 0.0%
Irrigation 0.0%
Agriculture 21.3%
Military 0.0%
Other Municipal
13.1%
805.3.7.2 State Water Systems
There are no State water systems in the Southeast Mauna Loa ASEA regulated by the DOH.
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-20
Hawaii County
Water Use and Development Plan Update
805.3.7.3 Federal Water Systems
There are no Federal water systems in the Southeast Mauna Loa ASEA regulated by the DOH.
805.3.7.4 Private Public Water Systems
The Punaluu Water & Sanitation Company owns the Punaluu water system, which serves the Sea
Mountain Resort and surrounding area. Water is supplied by two Ninole wells and disinfected
with chlorine gas prior to distribution. Storage is provided by the 1.0 MG reservoir north of
Hawaii Belt Road. The service area includes the nursery taps, administration office, tennis
courts, Colony 1 Condos, golf club house, Punaluu Beach Park, Punaluu Village Restaurant, and
the Kalana Estates subdivision north of the highway. According to DOH records, domestic
usage is 0.02 mgd.
805.3.8 Water Use by Resource
805.3.8.1 Ground Water
Table 805-9 summarizes the current production, potential production (16 and 24-hour
operation), sustainable yield (SY), and percentage of SY for the various productions calculated.
Current production is represented by the highest 12-month moving average (MAV) or the
highest annual average yield calculated from the actual pumpage data. Potential well production
is based on installed pump capacities, and calculated for both 16 hours of operation a day and 24
hours of operation a day. Data is based on pumpage data reported to CWRM.
Table 805-9: Sustainable Yield – Southeast Mauna Loa Aquifer Sector Area
Sys Code System Area
High
12-Month MAV
(MGD)
Potential
16 -Hour Production
(MGD)
Potential
24-Hour Production
(MGD) SY (MGD)
High
12-Month
MAV
SY
(%)
Potential
16-Hour
Production
SY
(%)
Potential
24-Hour
Production
SY
(%)
0.22 5.17 7.75 291 0.08 1.78 2.66
80501 Olaa 0.00 0.00 0.00 124 0.00 0.00 0.00
80502 Kapapala 0.00 0.00 0.00 19 0.00 0.00 0.00
80503 Naalehu 0.22 5.17 7.75 117 0.19 4.42 6.62
80504 Ka Lae 0.00 0.00 0.00 31 0.00 0.00 0.00
DWS utilizes two spring and one tunnel source as described previously. Usage between
November 2004 and October 2005 was 0.62 mgd.
805.3.8.2 Surface Water
Flow data is not available for any of the spring and stream diversions listed previously in Table
805-5. As described previously, water usage from the Noguchi Tunnels is not readily available.
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-21
Hawaii County
Water Use and Development Plan Update
805.3.8.3 Rainwater Catchment
Water consumption calculated for developed parcels that are not supplied by groundwater or
surface water is assumed to be supplied by rainwater catchment. The water use previously
categorized as Domestic Use in Table 805-7 is assumed to be supplied by individual catchment
systems.
805.3.8.4 Reclaimed Wastewater
Reclaimed wastewater from the wastewater treatment plant within the Southeast Mauna Loa
ASEA is used for golf course irrigation. Refer to Table 805-6 presented earlier.
805.4 FUTURE WATER NEEDS
805.4.1 General
Table 805-10 summarizes the LUPAG, Zoning and 5-year incremental water demand projection
scenarios for the total aquifer sector area and the individual aquifer system areas. The
sustainable yield (SY) is presented to draw comparisons.
Table 805-10: Summary of Demand Projections
Growth Rate B Demand Projections (mgd)Without
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total S.E. Mauna Loa ASEA 291 13.7 3.7 1.2 1.3 1.5 1.6 1.8
80501 – Olaa ASYA 124 1.5 0.4 0.3 0.3 0.4 0.5 0.5
80502 – Kapapala ASYA 19 0.0 0.0 0.0 0.0 0.0 0.0 0.0
80503 – Naalehu ASYA 117 10.8 2.9 0.7 0.8 0.8 0.9 1.0
80504 – Ka Lae ASYA 31 1.4 0.4 0.2 0.2 0.2 0.3 0.3
Growth Rate B Demand Projections (mgd)With
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total S.E. Mauna Loa ASEA 291 159.3 147.6 4.8 5.3 5.8 6.4 7.1
80501 – Olaa ASYA 124 22.1 20.3 0.8 0.9 1.1 1.3 1.5
80502 – Kapapala ASYA 19 1.0 1.0 0.0 0.0 0.0 0.0 0.0
80503 – Naalehu ASYA 117 113.3 105.1 3.2 3.6 3.9 4.2 4.6
80504 – Ka Lae ASYA 31 22.9 21.3 0.7 0.8 0.8 0.9 1.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
For all aquifer system areas, full build-out and 2025 projection water demands excluding
agricultural demands are a small fraction the SY. Therefore, analysis of the three demand
scenarios does not need to be broken down by aquifer system areas and thus will be presented for
the aquifer sector area only.
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-22
Hawaii County
Water Use and Development Plan Update
805.4.2 Full Build-Out Water Demand Projections
The full build-out water demand projections based on the General Plan and County Zoning for
the Southeast Mauna Loa ASEA are listed in Tables 805-11 and 805-12, and reflect refinement
as discussed below. Each land use class is associated with the most appropriate CWRM water
use category.
Table 805-11: Hawaii County General Plan Full Build-Out Water Demand Projection –
Southeast Mauna Loa Aquifer Sector Area
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 8.8
Urban Expansion Domestic/Irrigation/Municipal 1.7
Resort Irrigation/Municipal 0.5
Industrial Industrial 0.3
Agriculture Agriculture 145.6
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 1.5
DHHL Irrigation/Municipal 0.8
TOTAL w/o Ag* 13.7
TOTAL w/ Ag* 159.3
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 805-12: County Zoning Full Build-Out Water Demand Projection – Southeast
Mauna Loa Aquifer Sector Area
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 2.0
Resort Irrigation/Municipal 0.5
Commercial Municipal 0.2
Industrial Industrial 0.2
Agriculture Agriculture 144.0
DHHL Irrigation/Municipal 0.8
TOTAL w/o Ag* 3.7
TOTAL w/ Ag* 147.6
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
805.4.2.1 Refine Land Use Based Projection
805.4.2.1.1 State Water Projects Plan
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-23
Hawaii County
Water Use and Development Plan Update
The total projected demand to the year 2020 for 7 State Water Projects within the Southeast
Mauna Loa ASEA is 0.05 mgd, using 0.04 mgd potable, and 0.01 nonpotable using potable
sources. These demands account for less than 1 percent of the projected total demand for the
sector area. The project that will generate the most significant demand, with the exception of
DHHL projects, which are covered separately, is listed in Table 805-13.
Table 805-13: Future State Water Projects to Generate Significant Demands
Project Name
Primary Use
State
Department
2020 Demand
(mgd)
Naalehu Elementary New 6 Classroom Potable DOE 0.01
805.4.2.1.2 State Department of Hawaiian Home Lands
There are four tracts in the Southeast Mauna Loa ASEA owned by the DHHL.
The Kamaoa-Puueo Tracts are located in the South Point area covering over 11,000 acres up to
an elevation of about 1,200 feet. Estimated demand for the existing pastoral and farm, and
proposed pastoral lots is 0.38 mgd. The Waiohinu Tract is a small 261-acre tract located on
steep terrain north of Waiohinu. The demand for the proposed agricultural lots and a few
commercial lots is 0.40 mgd. Both tracts would be supplied by the DWS Naalehu-Waiohinu
Water System. DHHL Special Report #2 indicates that an additional well source would be
required to assure reliable and consistent supply.
The Discover Harbor tract was recently acquired by DHHL. It consists of 40 lots within the
Discovery Harbor subdivision northeast of Puueo. The lots are already serviced by the DWS
Naalehu-Waiohinu Water System with an estimated demand of 0.02 mgd.
The Olaa-Kurtistown tract consists of lots in the Kurtistown, Glenwood, and Volcano areas
totaling 707 acres in the Puna District. The total water need 0.03 mgd. Service laterals to the
DWS Olaa-Mt.View WS are already in place for the Kurtistown lots. DHHL Special Report #2
proposes that the remaining lots will be served by rainwater catchment.
805.4.2.1.3 Agricultural Water Use and Development Plan
There is no information available in the AWUDP specific to activity within the Southeast Mauna
Loa ASEA to further refine projections.
805.4.3 Water Use Unit Rates
Water use unit rates are based on the Water System Standards as discussed in Chapter 1.
805 Southeast Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
805.4.4 5-Year Incremental Water Demand Projection to the Year 2025
The following section presents 5-year incremental water demand projections to the year 2025 for
the Southeast Mauna Loa ASEA. The projected low, medium, and high growth rates are listed in
Table 805-14, and are graphed in Figure 805-8. Potable and nonpotable water demands are also
differentiated.
Figure 805-9 illustrates the magnitude of the sustainable yield, both LUPAG and Zoning full
build-out water use, and water use projection through the year 2025 focusing on Medium Growth
Rate B. Figure 805-10 shows the breakdown of water demand projections by CWRM categories
through the year 2025. Table 805-15 summarizes these figures.
Table 805-14: Water Demand Projection – Southeast Mauna Loa Aquifer Sector Area
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 1.2 1.3 1.4 1.6 1.8 4.8 5.2 5.8 6.3 7.0
Potable 0.9 1.0 1.1 1.3 1.4 0.9 1.0 1.1 1.3 1.4
Nonpotable 0.3 0.3 0.3 0.3 0.4 3.9 4.2 4.6 5.1 5.6
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 1.2 1.3 1.5 1.6 1.8 4.8 5.3 5.8 6.4 7.1
Potable 0.9 1.0 1.1 1.3 1.4 0.9 1.0 1.1 1.3 1.4
Nonpotable 0.3 0.3 0.3 0.4 0.4 3.9 4.3 4.7 5.2 5.7
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 1.2 1.3 1.5 1.7 1.9 4.8 5.4 6.0 6.7 7.5
Potable 0.9 1.0 1.2 1.3 1.5 0.9 1.0 1.2 1.3 1.5
Nonpotable 0.3 0.3 0.3 0.4 0.4 3.9 4.3 4.9 5.4 6.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-25
Hawaii County
Water Use and Development Plan Update
Figure 805-8: Water Demand Projection Summary – Southeast Mauna Loa Aquifer Sector
Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 805-15: Medium Growth Rate B Water Demand Projection by Category – Southeast
Mauna Loa Aquifer Sector Area
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 1.2 1.3 1.5 1.6 1.8
Total with Ag* 4.8 5.3 5.8 6.4 7.1
Domestic 0.3 0.4 0.4 0.5 0.6
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 0.3 0.3 0.3 0.4 0.4
Agriculture 3.6 4.0 4.4 4.8 5.3
Military 0.0 0.0 0.0 0.0 0.0
Municipal 0.6 0.6 0.7 0.8 0.9
Potable 0.9 1.0 1.1 1.3 1.4
Nonpotable w/o Ag* 0.3 0.3 0.3 0.4 0.4
Nonpotable w/ Ag* 3.9 4.3 4.7 5.2 5.7
DWS 0.6 0.6 0.7 0.8 0.8
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
2005 2010 2015 2020 2025
YearDemand (mgd)Nonpotable w/o Ag
Potable
Total w/o Ag
Nonpotable w/ Ag
Potable
Total w/ Ag
LEGEND: Growth Rate A Growth Rate B Growth Rate C
805 Southeast Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 805-9: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Southeast Mauna Loa Aquifer Sector Area
0
50
100
150
200
250
300
350
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 291
LUPAG = 14–159Zoning = 4–148
Legend*, **
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-27
Hawaii County
Water Use and Development Plan Update
Figure 805-10: Medium Growth Rate B Water Demand Projection by Category –
Southeast Mauna Loa Aquifer Sector Area
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
805.4.5 DWS Historical Water Consumption Data Projections
DWS supplied water consumption was projected in 5-year increments to the year 2025 based on
DWS historical water system consumption data from 1970 to 2003, as shown on Figure 805-11.
Legend*, **
805 Southeast Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 805-11: DWS Water Demand Projection – Southeast Mauna Loa Aquifer Sector
Area
S.E. Mauna Loa Aquifer Sector Water Systems
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1970 1980 1990 2000 2010 2020mgdHistorical Projected
Year 2005: 0.72 mgd
Year 2010: 0.77 mgd
Year 2015: 0.81 mgd
Year 2020: 0.85 mgd
Year 2025: 0.90 mgd
This graph combines data for the
Waiohinu-Naalehu, and Pahala water
systems.
Historical data provided by RW Beck, Inc.
Projections based on historical DWS water consumption data are quite different than projections
based on population growth rate. The actual 2005 consumption is considerably lower than the
projection based on historical consumption. Also, the projected future growth rate of the
population is much greater than the rate of increase of the historical consumption. DWS may
need to supply potable water equivalent to as much as half of the total projected water supply for
the sector area.
805 Southeast Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
805.5 RESOURCE AND FACILITY RECOMMENDATIONS
805.5.1 Water Source Adequacy
805.5.1.1 Full Build-Out
Full development to the maximum density of the County General Plan and Zoning land uses
within the Southeast Mauna Loa Aquifer Sector Area (ASEA) can be sustained by conventional
water resources. If agricultural demands are excluded, LUPAG water demands amount to less
than 5 percent of the sustainable yield (SY) of the sector area, and existing Zoning requires
approximately 1 percent of the SY. If worst case agricultural demands are included, the LUPAG
and Zoning demand scenarios would require 51 and 55 percent of the SY, respectively.
805.5.1.2 Twenty-Year Projection
20-year projected demands range between less than 1 and 3 percent of the SY of the sector area.
805.5.2 Source Development Requirements
805.5.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, are evaluated to meet projected water demands.
805.5.2.1.1 Conventional Water Resource Measures
805.5.2.1.1.1 Ground Water
The nature of the groundwater is very different between the four aquifer system areas that
comprise the Southeast Mauna Loa ASEA. The Olaa and Kapapala Aquifer System Areas
(ASYA), consist of high level perched and dike water at great depths. Development of this water
would be extremely expensive. The Naalehu and Ka Lae ASYAs, both reaching the southern
coast, contain basal water several miles inland. The Naalehu ASYA contains perched and dike-
impounded high level water further inland.
Development of potable water wells should continue in the Naalehu ASYA, considering most of
the proposed development will occur within this system. DWS has proposed a second well in
Pahala and a well in Waiohinu to meet the needs of the two respective water systems.
Nonpotable wells may be developed to serve localized nonpotable uses as they arise.
The output of the spring and tunnel sources fluctuates throughout the year, and is greatly
diminished during dry periods. Existing potable sources may continue to be used as long as
Federal SDWA regulations are met, however new sources are not likely to be developed due to
805 Southeast Mauna Loa Aquifer Sector Area
Page 805-30
Hawaii County
Water Use and Development Plan Update
the remoteness from proposed development areas. Nevertheless, a significant quantity of water
remains available as an alternative to groundwater wells.
805.5.2.1.1.2 Surface Water
Surface water may continue as the primary resource to supply nonpotable needs. The challenge
concerning surface water is the transmission, not the availability of sources.
805.5.2.1.1.3 Water Transfer
Water is currently being transferred between aquifer system areas within the Southeast Mauna
Loa ASEA, from the Naalehu ASYA to the Ka Lae ASYA, through the DWS Waiohinu-Naalehu
Water System. Refer to Figure 805.6. Potable water sources are readily available in the
Naalehu ASYA; therefore, water transfer is expected to continue and likely increase with
potential Hawaiian Home Lands developments in South Point.
Water transfer may also be considered to supply developments in the southern areas of the
Southwest Mauna Loa ASEA (806). This issue will be examined in greater detail in Chapter
806.
805.5.2.1.2 Alternative Water Resource Enhancement Measures
805.5.2.1.2.1 Rainwater Catchment Systems
Most of the developed areas in the Naalehu ASYA and the eastern half of the Olaa ASYA
receive enough rainfall to support catchment. Individual systems are unlikely to be used if a
municipal water system is available, although a large-scale catchment system may be considered
to supplement a municipal system. The majority of homes using individual catchments in the
sector area are in the eastern portion of the Olaa ASYA outside the extent of the DWS Olaa-Mt.
View Water System. Usage of catchments in these areas could potentially increase if growth
proceeds as planned without extension of the municipal water system.
805.5.2.1.2.2 Wastewater Reclamation
Reclaimed wastewater is currently being used for irrigation of the golf course at the Punaluu
Resort. Usage is not expected to increase without additional development of the resort. In
general, reclaimed wastewater is not considered a significant alternative considering the small
service populations contributing to wastewater flow, and the availability of other nonpotable
sources.
805.5.2.1.2.3 Desalination
Because potable water is available inland, only coastal areas of the Ka Lae ASYA that where
only brackish groundwater exists would be considered for desalination facilities. Potable water
service already extends to the South Point and Discovery Harbor areas; furthermore, unit costs
805 Southeast Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
would be extremely high considering the small service area. Desalination is unlikely to be
implemented in favor of conventional alternatives, such as upgrading the existing source and
transmission infrastructure.
805.5.2.2 Demand-Side Management
805.5.2.2.1 Development Density Control
Full build-out demands associated with LUPAG maximum density are nearly four times greater
than that of Zoning. Additional sources will eventually be required, however, these demands are
sustainable by conventional resources. Therefore, control of development density is not
considered critical.
805.5.2.2.2 Water Conservation
The average water use per connection to the DWS water system is 400 gpd, and the average
current potable water usage per capita from all sources is approximately 150 gpd, both of which
are exactly island averages. Demand-side water conservation should continue, but measures do
not need to be implemented.
The water not accounted for in the DWS Waiohinu-Naalehu Water System ranges between 20
and 40 percent, which is high. The total quantity of water unaccounted for amounts to less than
0.25 mgd, therefore supply-side conservation should be planned, but need not be a high priority.
805.5.3 Recommended Alternatives
Potable groundwater development should continue in the Naalehu ASYA to suit anticipated
development. Consistent with the General Plan, groundwater source investigation and well
development should proceed at Pahala and Waiohinu.
Surface water sources should be developed to meet anticipated nonpotable water demands.
Existing irrigation systems should be evaluated to determine the extent of infrastructure
improvements and additional source development required to attain optimal function. It is
anticipated that the next phase of the update to the AWUDP will address these issues in greater
detail, specifically considering the Kau Flume System.
Because the sustainable yield of the sector is large compared to the projected demands, and can
be reasonably developed, the potential exists to transfer potable water to the neighboring
Southwest Mauna Loa ASEA if potable water sources cannot be feasibly developed there.
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-1
Hawaii County
Water Use and Development Plan Update
806 SOUTHWEST MAUNA LOA AQUIFER SECTOR AREA
806.1 SECTOR AREA PROFILE
806.1.1 General
The Southwest Mauna Loa Aquifer Sector Area (ASEA) includes the Manuka [80601], Kaapuna
[80602] and the Kealakekua [80603] Aquifer System Areas (ASYA), encompassing the entire
South Kona District, the southeastern portion of the North Kona District, and the western portion
of the Kau District. The boundaries extend from the summit of Mauna Loa to the western shores
near Kealakekua, and along the western coastline to the southern tip of the island at Ka Lae.
Rainfall varies from an average of less than 20 inches per year in some coastal areas to 125
inches per year in higher elevation areas above Honaunau. Rainfall in the Kaapuna and
Kealakekua ASYAs are diurnal rather than orthographic due to Mauna Loa blocking the
tradewinds. The three aquifer system areas have similar sustainable yields, with the Kaapuna
ASYA at 50 mgd, the Manuka ASYA at 42 mgd, and the Kealakekua ASYA at 38 mgd. The
total sustainable yield for the entire sector area is 130 mgd.
806.1.2 Economy and Population
806.1.2.1 Economy
Agriculture is the most important economic activity within the sector area. Coffee and
macadamia nuts are the primary industries, with over 4,000 acres of macadamia nut orchards,
and the famed “coffee belt” mauka of Mamalahoa Highway. Although the coffee industry has
proven to be volatile; the number of coffee farms and corresponding sales have fluctuated,
varying from a low of $3.7 million in 1992 to $16.2 million in 1997; nevertheless it remains one
of the principals of Kona’s economy. Both products’ industries include processing operations.
South Kona accounts for 20 to 25 percent of the macadamia nut processing statewide. Cattle
ranching and growing of citrus fruits and bananas are also important within the sector area.
Tourism does not play a large part in the sector’s economy. Visitor accommodations are limited;
the 88-unit Manago Hotel in Captain Cook is the largest establishment for overnight visitors.
The 730-lot and golf course Hokulia development and 80-unit lodge is under construction.
806.1.2.2 Population
More than three quarters of the population contributing to the demands from the Southwest
Mauna Loa ASEA is within the South Kona District, and the balance is from the Kau District.
The growth of the Ocean Point Community has and will continue to be significant.
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-2
Hawaii County
Water Use and Development Plan Update
Table 806-1: Historical Population
1980 1990 2000
1980-90
% Change
1990-2000
% Change
7,430 9,553 11,068 28.6 15.9
Data Source: 2000 U.S. Census
Data redistributed and evaluated for Southwest Mauna Loa Aquifer Sector Area
Table 806-2: Population Projection
Growth
Rate 2000 2005 2010 2015 2020
2000-10
% Change
2010-20
% Change
A – Low 11,068 12,938 14,280 15,727 17,331 29.0 21.4
B – Medium 11,068 12,980 14,407 15,959 17,684 30.2 22.7
C – High 11,068 13,521 15,310 17,212 19,276 38.3 25.9
Data Source: County General Plan, February 2005
Data redistributed and evaluated for Southwest Mauna Loa Aquifer Sector Area
806.1.3 Land Use
806.1.3.1 Hawaii County General Plan
The Hawaii County General Plan Land Use Pattern Allocation Guide Map (LUPAG) for the
Southwest Mauna Loa ASEA is shown on Figure 806-1. The estimated land use allocation
acreage for each LUPAG designation within the sector area is listed in Table 806-3.
LEGEND:Hawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-818FUKUNAGA & ASSOCIATES, INC.Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
INDEX MAP - Island of Hawaii
2 0 21
Miles
2005 Revised GeneralPlan Land Use PatternAllocation Guide
Extensive Agriculture
Important Agricultural Land
Orchard
High Density Urban
Medium Density Urban
Low Density Urban
Industrial
Urban Expansion
Resort
Resort Node
Rural
Conservation
Open
University Use
Pond
Break Water
FIGURE 806-1
AQUIFER SECTOR
S.W. MAUNA LOA - 806Aquifer Systems
Developed Properties
Hawaiian Home Lands
Land Use Pattern Allocation Guide
Manuka - 80601Kaapuna - 80602Kealakekua - 80603
Kauna Pt.
Kau Loa Pt.
Okoe Bay
Ka Lae Pt.
Ka Lae Pt.
Manuka80601
P A C I F I C O C E A N
Manuka80601
Okoe Bay
Loa Pt.
Kealakekua Bay
Kaapuna80602
Kealakekua80603
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-5
Hawaii County
Water Use and Development Plan Update
Table 806-3: LUPAG Map Estimated Land Use Allocation Acreage Southwest Mauna Loa
Aquifer Sector Area
LAND USE PATTERN ACREAGE
% of
TOTAL
High Density Urban 0 0
Medium Density Urban 370 0.1
Low Density Urban 1,291 0.3
Industrial 0 0
Important Agricultural Land 36,622 9.2
Extensive Agriculture 141,946 35.6
Orchard 1,224 0.3
Rural 10,631 2.7
Resort/Resort Node 25 0.0
Open 4,362 1.1
Pond 0 0
Conservation 201,685 50.6
Urban Expansion 273 0.1
University Use 0 0
TOTAL 398,429 100.0
The water utility courses of action for South Kona and Kau in the Hawaii County General Plan
relevant to the sector area are as follows:
(a) Continue to pursue groundwater source investigation, exploration and development in
areas that would provide for anticipated growth and an efficient and economic system
operation.
(b) Continue to evaluate growth conditions to coordinate improvements as required to the
existing water system in accordance with the South Kona Water System Master Plan.
(c) Pursue groundwater source investigation, exploration and well development at Ocean
View.
(d) Investigate alternative means to finance the extension of water systems to subdivisions
that rely on catchment.
806.1.3.2 Hawaii County Zoning
Hawaii County Zoning for the Southwest Mauna Loa ASEA is shown on Figure 806-2. The
estimated land use allocation acreage for each zoning class within the sector area is listed in
Table 806-4.
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-6
Hawaii County
Water Use and Development Plan Update
Table 806-4: County Zoning Estimated Class Allocation Acreage – Southwest Mauna Loa
Aquifer Sector Area
ZONING CLASS ACREAGE
% of
TOTAL
Single Family Residential 445 0.11
Multi-Family Residential
(including duplex) 60.00
Residential-Commercial Mixed Use 0 0
Resort 15 0.00
Commercial 123 0.03
Industrial 0 0
Industrial-Commercial Mixed 0 0
Family Agriculture 13 0.00
Residential Agriculture 150 0.04
Agriculture 215,929 54.20
Open 136,581 34.28
Project District 23 0.01
Forest Reserve 42,949 10.78
(road) 2,194 0.55
TOTAL 398,429 100.00
806.2 EXISTING WATER RESOURCES
806.2.1 Ground Water
Southwest Mauna Loa ASEA has a sustainable yield of 130 mgd. According to the CWRM
database, there are 16 production wells in the sector, including 5 municipal, 5 irrigation, 4
domestic, and 2 other. There are also 2 wells drilled and categorized as “unused”. Refer to
Appendix B for this database. Figure 806-3 shows the well locations.
806.2.2 Surface Water
There are no streams classified as perennial in the sector area. The Kiilae Stream flowing into
Kauhako Bay at Hookena is intermittent.
There are 4 declared stream diversions in the CRWM database listed in Table 806-5 and shown
on Figure 806-4. The two Kiilae Stream diversions have declared flows, the other two do not.
LEGEND:Hawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-8182 0 21
Miles
Agricultural - 1 thru 10 acresAgricultural - 20 acresAgricultural - 35 acresAgricultural - 40 acresAgricultural - 80 acresAgricultural - 200 thru 255 acresAgricultural - 500 acresAgricultural - 600 acresAgricultural - 800 acresAgricultural - 900 acresAgricultural Project DistrictsDowntown Hilo Commercial DistrictCommercial, GeneralCommercial, NeighborhoodCommercial, VillageFamily AgriculturalForest ReserseIndustrial - CommercialIndustrial, GeneralIndustrial, LimitedOpenProject DistrictsResidentail and AgriculturalResidential - Commercial Mixed UseResidential Double-FamilyRes. Multi-Family - 7500-8000 sfRes. Multi-Family - 14,500-20,000 sfRes. Single Family - 7500-10,000 sfRes. Single Family - 15,000-20,000 sfHotel/Resort
Zoning Designations:
A-1a+A-20aA-35aA-40aA-80aA-200+A-500aA-600aA-800aA-900aAPDCDHCGCNCVFAFRMCXMGMLOPDRARCXRDRM-7.5+RM-14.5+RS-7.5+RS-15+V
Developed ParcelsHawaiian Home Lands
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
INDEX MAP - Island of Hawaii
County Zoning
FIGURE 806-2
AQUIFER SECTORS.W. MAUNA LOA - 806Aquifer SystemsManuka - 80601Kaapuna - 80602Kealakekua - 80603
Kauna Pt.
Kau Loa Pt.
Okoe Bay
Ka Lae Pt.
Ka Lae Pt.
Manuka80601 P A C I F I C O C E A N
Manuka80601
Okoe Bay
Loa Pt.
Kaapuna80602
Kealakekua80603
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-9
Hawaii County
Water Use and Development Plan Update
Figure 806-3: Well and Tunnel Location
MAP CURRENTLY NOT AVAILABLE ON-LINE
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-11
Hawaii County
Water Use and Development Plan Update
Figure 806-4: Streams & Diversions
MAP CURRENTLY NOT AVAILABLE ON-LINE
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-13
Hawaii County
Water Use and Development Plan Update
Table 806-5: Stream Diversions – Southwest Mauna Loa Aquifer Sector Area
FILE REFERENCE TMK STREAM NAME
CARLSMITH DW 8-9-010:004 Unnamed Spring Spring diversion, pipe from Kalihi Spring.
MCCANDLESS
RAN 8-5-001:002 Kiilae
Stream diversion Pipe #1 from Kiilae Stream. See also new
entry for Pipe #2. Delcared Q of 4.0 MG is the total for both
pipes.
MCCANDLESS
RAN 8-5-001:002 Kiilae Stream diversion, Pipe #2 from Kiilae Stream (new entry).
Declared Q of 4.0 MG is the total for both pipes.
TANOAI A 8-3-011:043 Unnamed/ Unmapped
Stream diversion, pump from Wailapa Stream. Stream is
noted to be located 150 ft from house, but not shown on
USGS. Lat/long taken at location of structure on USGS.
806.2.3 Reclaimed Wastewater
There are no wastewater reclamation facilities in the Southwest Mauna Loa ASEA.
806.3 EXISTING WATER USE
806.3.1 General
The total estimated average water use within the Southwest Mauna Loa ASEA from 2004 to
2005 (DWS meter data and CWRM pumpage data from November 2004 through October 2005
and available GIS data) is listed in Table 806-6. Table 806-6 and Figure 806-5 summarize
water use in accordance with CWRM categories and indicate separately the quantities supplied
excluding agricultural demands, and the quantities supplied including worst case agricultural
demands (as described in Chapter 2) by the DWS system and non-DWS systems.
Table 806-6: Existing Water Use by Categories – Southwest Mauna Loa Aquifer Sector
Area
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.73 28.6 13.2
Industrial 0.00 0.0 0.0
Irrigation 0.71 27.7 12.7
Reclaimed WW 0.00 0.0 0.0
Agriculture 3.01 0.0 53.9
Military 0.00 0.0 0.0
Municipal
DWS System 1.12 43.7 20.1
Private Public WS 0.00 0.0 0.0
Total without Ag* 2.57 100.0
Total with Ag* 5.57 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-14
Hawaii County
Water Use and Development Plan Update
Figure 806-5: Existing Water Use by Categories – Southwest Mauna Loa Aquifer Sector
Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 806-6 generally shows the service area for the various water systems and indicates the
extent of the DWS water system.
806.3.2 Domestic Use
Domestic use or water use by individual households is assumed to be supplied by private
individual rainwater catchment systems or private wells. Based on available GIS data, there are
1,731 developed parcels serving approximately 4,700 people, which is 37 percent of the sector
area population. The estimated demand is 0.73 mgd. None of the four wells classified as
“Domestic” in the CWRM database report pumpage.
806.3.3 Industrial Use
There is no reported industrial usage in the CWRM well database.
806.3.4 Irrigation Use
Irrigation is based on pumpage reported for private wells categorized by CWRM as irrigation
wells. Table 806-7 indicates the average for private irrigation well pumpage reported to CWRM
or listed in the 2003 SWPP.
Domestic 28.6%
Industrial 0.0%
Irrigation 27.7%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 0.0%
Municipal
(DWS) 43.7%
Domestic 13.2%
Industrial 0.0%
Irrigation 12.7%Irrigation (Recl'd
WW) 0.0%
Agriculture 53.9%
Military 0.0%
Municipal
(Non-DWS) 0.0%
Municipal
(DWS) 20.1%
w/o Agricultural Water Use*with Agricultural Water Use*
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-17
Hawaii County
Water Use and Development Plan Update
Table 806-7: Private Irrigation Well Pumpage
Private Irrigation Irrigation Well Pumpage (mgd)
Mac Farms Hawaii 0.16
Kona Horizons Ltd. 0.01
1250 Oceanside Partners 0.54
TOTAL 0.71
There are no golf courses located within the Southwest Mauna Loa ASEA.
806.3.5 Agricultural Use
According to the 2003 South Kona Watershed Irrigation System Study (SKWIS), the agricultural
water usage within the 15,000-acre study area immediately south of the Papa Bay Homesteads is
supplied by catchment systems. Water trucks have provided water from the DWS South Kona
Water System during drought periods, which may contribute to the 0.12 mgd drawn from the
DWS water system from accounts classified as “Agricultural.”
806.3.6 Military Use
There is no military use in the Southwest Mauna Loa ASEA.
806.3.7 Municipal Use
Municipal use can be subcategorized into the other water use categories, namely Domestic,
Industrial, Irrigation, Agriculture, and Military, if detailed information is available.
806.3.7.1 County Water Systems
The DWS has one system in the Southwest Mauna Loa ASEA. The South Kona Water System
interconnects with the North Kona Water System a short distance from the district boundary at
Konawaena School. The principal source for the water system is the Keei Well field, however
three of the four wells are used as backup only. In 1997, the Halekii Well at Kealakekua was
brought into service. The water system extends south to Hookena, a distance of 16 miles. Eight
booster pump stations, nine storage tanks and over twenty PRV’s allow eleven operational zones
to be serviced. A connection to the North Kona System exists along Mamalahoa Highway. The
normally closed valve may be opened in case of emergencies.
DWS water use is subcategorized in Table 806-8 to the extent possible based on available meter
data and is depicted in Figure 806-7. “Other Municipal” includes facilities such as schools, and
various commercial, government, medical and nonprofit entities which have mixed water use and
cannot be specifically allocated to the other categories.
806 Southwest Mauna Loa Aquifer Sector Area
Page 806-18
Hawaii County
Water Use and Development Plan Update
Table 806-8: DWS Existing Water Use by Categories – Southwest Mauna Loa Aquifer
Sector Area
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 0.75 66.7
Industrial 0.00 0.0
Irrigation 0.00 0.0
Agriculture 0.16 14.2
Military 0.00 0.0
Other Municipal 0.21 19.1
Total 1.12 100.0
Figure 806-7: DWS Existing Water Use by Categories – Southwest Mauna Loa Aquifer
Sector Area
Domestic 66.7%
Industrial 0.0%
Irrigation 0.0%
Agriculture 14.2%
Military 0.0%
Other Municipal
19.1%
806.3.7.2 State Water Systems
There are no State water systems in the Southwest Mauna Loa ASEA regulated by the DOH.
806.3.7.3 Federal Water Systems
There are no Federal water systems in the Southwest Mauna Loa ASEA regulated by the DOH.
806 Southwest Mauna Loa Aquifer Sector Area
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806.3.7.4 Private Public Water Systems
There are no private public water systems in the Southwest Mauna Loa ASEA regulated by the
DOH.
806.3.8 Water Use by Resource
806.3.8.1 Ground Water
Table 806-9 summarizes the current production, potential production (16 and 24-hour
operation), sustainable yield (SY), and percentage of SY for the various productions calculated.
Current production is represented by the highest 12-month moving average (MAV) or the
highest annual average yield calculated from the actual pumpage data. Potential well production
is based on installed pump capacities, and calculated for both 16 hours of operation a day and 24
hours of operation a day. Data is based on pumpage data reported to CWRM.
Table 806-9: Sustainable Yield – Southwest Mauna Loa Aquifer Sector Area
Sys Code System Area
High
12-Month
MAV
(MGD)
Potential
16 -Hour
Production
(MGD)
Potential
24-Hour
Production
(MGD) SY (MGD)
High
12-Month
MAV
SY
(%)
Potential
16-Hour
Production
SY
(%)
Potential
24-Hour
Production
SY
(%)
2.38 6.92 10.38 130 1.83 5.32 7.98
80601 Manuka 0.16 0.79 1.18 42 0.38 1.87 2.81
80602 Kaapuna 0.01 0.40 0.60 50 0.02 0.80 1.20
80603 Kealakekua 2.17 5.73 8.60 38 5.71 15.09 22.63
806.3.8.2 Surface Water
The 15,000-acre McCandless Ranch near Kalahiki uses two diversions of the Kiilae Stream with
a total declared flow of 8.0 mgd; however, the actual quantity used is not readily available.
806.3.8.3 Rainwater Catchment
Water consumption calculated for developed parcels that are not supplied by groundwater or
surface water is assumed to be supplied by rainwater catchment. The water use previously
categorized as Domestic Use in Table 806-6 is assumed to be supplied by individual catchment
systems.
As mentioned previously, the SKWIS Study indicates that catchment reservoir systems are
utilized by agricultural users to supplement natural precipitation.
806 Southwest Mauna Loa Aquifer Sector Area
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806.3.8.4 Reclaimed Wastewater
There is no reclaimed wastewater usage in the sector area.
806.4 FUTURE WATER NEEDS
806.4.1 General
Table 806-10 summarizes the LUPAG, Zoning and 5-year incremental water demand projection
scenarios for the total aquifer sector area and the individual aquifer system areas. The
sustainable yield (SY) is presented to draw comparisons.
Table 806-10: Summary of Demand Projections
Growth Rate B Demand Projections (mgd)Without
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total S.W. Mauna Loa ASEA 130 18.0 1.5 2.6 2.8 3.2 3.5 3.9
80601 – Manuka ASYA 42 7.7 0.0 0.5 0.6 0.7 0.7 0.8
80602 – Kaapuna ASYA 50 0.0 0.0 0.3 0.3 0.3 0.4 0.4
80603 – Kealakekua ASYA 38 10.3 1.4 1.7 1.9 2.2 2.4 2.7
Growth Rate B Demand Projections (mgd)With
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total S.W. Mauna Loa ASEA 130 142.5 123.1 5.6 6.2 6.8 7.6 8.4
80601 – Manuka ASYA 42 33.2 25.2 1.2 1.3 1.4 1.6 1.7
80602 – Kaapuna ASYA 50 40.8 40.4 1.3 1.4 1.6 1.8 2.0
80603 – Kealakekua ASYA 38 68.5 57.5 3.1 3.4 3.8 4.3 4.7
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
For all aquifer system areas, full build-out water demands excluding agricultural demands are
considerably less than the SY, and the 2025 demand projections excluding agricultural demands
are less than 10 percent of the system area SY. Therefore, analysis of the three demand
scenarios does not need to be broken down by aquifer system areas and thus will be presented for
the aquifer sector area only.
806.4.2 Full Build-Out Water Demand Projections
The full build-out water demand projections based on the General Plan and County Zoning for
the Southwest Mauna Loa ASEA are listed in Tables 806-11 and 806-12, and reflect refinement
as discussed below. Each land use class is associated with the most appropriate CWRM water
use category.
806 Southwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Table 806-11: Hawaii County General Plan Full Build-Out Water Demand Projection –
Southwest Mauna Loa Aquifer Sector Area
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 9.8
Urban Expansion Domestic/Irrigation/Municipal 1.4
Resort Irrigation/Municipal 0.4
Industrial Industrial 0.0
Agriculture Agriculture 124.5
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 6.4
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 18.0
TOTAL w/ Ag* 142.5
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 806-12: County Zoning Full Build-Out Water Demand Projection – Southwest
Mauna Loa Aquifer Sector Area
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 1.0
Resort Irrigation/Municipal 0.0
Commercial Municipal 0.4
Industrial Industrial 0.0
Agriculture Agriculture 121.6
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 1.5
TOTAL w/ Ag* 123.1
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
806.4.2.1 Refine Land Use Based Projection
806.4.2.1.1 State Water Projects Plan
The total projected demand to the year 2020 for 15 State Water Projects within the Southwest
Mauna Loa ASEA is 0.12 mgd, using 0.02 mgd potable, and 0.10 mgd nonpotable using potable
sources. These projects may account for 3 percent of the total projected water demand in the
sector area. The projects that will generate the most significant demands are listed in Table 806-
13.
806 Southwest Mauna Loa Aquifer Sector Area
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Table 806-13: Future State Water Projects to Generate Significant Demands
Project Name
Primary Use
State
Department
2020 Demand
(mgd)
Kealakekua Bay Ship
Nonpotable
using Potable State Parks 0.08
Kona Civic Center
Nonpotable
using Potable
DAGS –
Planning 0.02
806.4.2.1.2 State Department of Hawaiian Home Lands
There are no tracts of land in the Southwest Mauna Loa ASEA owned by the DHHL.
806.4.2.1.3 Agricultural Water Use and Development Plan
There is no information available in the AWUDP specific to activity within the Southwest
Mauna Loa ASEA to further refine projections.
806.4.3 Water Use Unit Rates
Water use unit rates are based on the Water System Standards as discussed in Chapter 1, and
single family residential (Low Density Urban category of the General Plan and RS-7.5 and
greater or Single-Family Residential categories of one lot per at least 7,500 acres of County
Zoning) consumption is based on 1.5 units per lot.
806.4.4 5-Year Incremental Water Demand Projection to the Year 2025
The following section presents 5-year incremental water demand projections to the year 2025 for
the Southwest Mauna Loa ASEA. The projected low, medium, and high growth rates are listed
in Table 806-14, and are graphed in Figure 806-8. Potable and nonpotable water demands are
also differentiated.
Focusing on Medium Growth Rate B, Figure 806-9 illustrates the magnitude of the sustainable
yield, both LUPAG and Zoning full build-out water use, and water use projection through the
year 2025. Figure 806-10 shows the breakdown of water demand projections by CWRM
categories through the year 2025. Table 806-15 summarizes these figures.
806 Southwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Table 806-14: Water Demand Projection – Southwest Mauna Loa Aquifer Sector Area
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 2.6 2.8 3.1 3.4 3.8 5.6 6.1 6.8 7.5 8.2
Potable 1.9 2.0 2.3 2.5 2.7 1.9 2.0 2.3 2.5 2.7
Nonpotable 0.7 0.8 0.9 0.9 1.0 3.7 4.1 4.5 5.0 5.5
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 2.6 2.8 3.2 3.5 3.9 5.6 6.2 6.8 7.6 8.4
Potable 1.9 2.1 2.3 2.5 2.8 1.9 2.1 2.3 2.5 2.8
Nonpotable 0.7 0.8 0.9 1.0 1.1 3.7 4.1 4.6 5.1 5.6
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 2.6 2.9 3.3 3.7 4.1 5.6 6.3 7.1 7.9 8.9
Potable 1.9 2.1 2.4 2.6 3.0 1.9 2.1 2.4 2.6 3.0
Nonpotable 0.7 0.8 0.9 1.0 1.1 3.7 4.2 4.7 5.3 5.9
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 806-8: Water Demand Projection Summary – Southwest Mauna Loa Aquifer Sector
Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
2005 2010 2015 2020 2025
YearDemand (mgd)Nonpotable w/o Ag*
Potable
Total w/o Ag*
Nonpotable w/ Ag*
Potable
Total w/ Ag*
LEGEND: Growth Rate A Growth Rate B Growth Rate C
806 Southwest Mauna Loa Aquifer Sector Area
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Table 806-15: Medium Growth Rate B Water Demand Projection by Category – Southwest
Mauna Loa Aquifer Sector Area
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 2.6 2.8 3.2 3.5 3.9
Total with Ag* 5.6 6.2 6.8 7.6 8.4
Domestic 0.7 0.8 0.9 1.0 1.1
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 0.7 0.8 0.9 1.0 1.1
Agriculture 3.0 3.3 3.7 4.1 4.5
Military 0.0 0.0 0.0 0.0 0.0
Municipal 1.1 1.2 1.4 1.5 1.7
Potable 1.9 2.1 2.3 2.5 2.8
Nonpotable w/o Ag* 0.7 0.8 0.9 1.0 1.1
Nonpotable w/ Ag* 3.7 4.1 4.6 5.1 5.6
DWS 1.1 1.2 1.4 1.5 1.7
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
806 Southwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Figure 806-9: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Southwest Mauna Loa Aquifer Sector Area
0
20
40
60
80
100
120
140
160
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 130
LUPAG = 18–143
Zoning = 1–123
Legend*, **
806 Southwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Figure 806-10: Medium Growth Rate B Water Demand Projection by Category –
Southwest Mauna Loa Aquifer Sector Area
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
806.4.5 DWS Historical Water Consumption Data Projections
DWS supplied water consumption was projected in 5-year increments to the year 2025 based on
DWS historical water system consumption data from 1970 to 2003, as shown on Figure 806-11.
Legend*, **
806 Southwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Figure 806-11: DWS Water Demand Projection – Southwest Mauna Loa Aquifer Sector
Area
South Kona Water System
0.0
0.5
1.0
1.5
2.0
2.5
3.0
1970 1980 1990 2000 2010 2020mgdHistorical Projected
Year 2005: 1.3 mgd
Year 2010: 1.5 mgd
Year 2015: 1.7 mgd
Year 2020: 1.9 mgd
Year 2025: 2.0 mgd
Historical data and graph provided by RW Beck, Inc.
Projections based on historical DWS water consumption data are slightly lower than projections
based on population growth rate, primarily because the projected demand for 2005 is lower than
actual data. The growth rate; however, is consistent with the projections for the total sector area,
and indicates that DWS may need to supply potable water of as much as half of the total
projected water supply for the Southwest Mauna Loa ASEA.
806 Southwest Mauna Loa Aquifer Sector Area
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806.5 RESOURCE AND FACILITY RECOMMENDATIONS
806.5.1 Water Source Adequacy
806.5.1.1 Full Build-Out
Full development to the maximum density of the County General Plan land use within the
Southwest Mauna Loa Aquifer Sector Area (ASEA) can be sustained by conventional water
resources. If agricultural demands are excluded, LUPAG water demands amount to less than 15
percent of the sustainable yield (SY) of the sector area, and the existing Zoning requires
approximately 1 percent of the sector area SY. If worst case agricultural demands are included,
the LUPAG demand scenario would exceed the SY, and Zoning demand scenario would require
95 percent of the SY.
806.5.1.2 Twenty-Year Projection
Existing demands range between 2 and 3 percent of the SY of the sector area, and 20-year
projected demands range between 4 and 7 percent of the SY.
806.5.2 Source Development Requirements
806.5.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, are evaluated to meet projected water demands.
806.5.2.1.1 Conventional Water Resource Measures
806.5.2.1.1.1 Ground Water
The basal groundwater lens extends at least six miles inland, is thin, difficult to develop, and a
significant portion may be brackish according to the WRPP. The existence of high-level water
has been shown by the development of the DWS Halekii and Keei 4 Wells in the Kealakekua
Aquifer System Area (ASYA). Further inland, high level water is present at 1,000 to 1,500 feet
beneath the ground surface. High level groundwater remains the most viable resource and
should continue to be developed. DWS has planned another high level well further south of the
existing Halekii Well. As no wells have been drilled mauka of Mamalahoa Highway south of
Keei in the sector area, the potential for high level groundwater is uncertain and needs to be
investigated further.
Potable basal water is one of the many potential options to the Ocean View area. Multiple wells
with smaller pumping rates spread out would be necessary to avoid drawing brackish water.
The 2003 SKWIS study indicates that either high level potable sources or low level nonpotable
sources may be developed to supply a future agricultural irrigation system in the study area,
806 Southwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
which is split by Mamalahoa Highway and is bound by Ocean View to the south and Papa Bay
Homesteads to the north. The service area may also be extended to supply the Ocean View area.
806.5.2.1.1.2 Surface Water
Surface water is not considered a viable resource as shown by the limited number of stream
diversions and the lack of perennial streams in the sector area.
806.5.2.1.1.3 Water Transfer
One of the alternatives to supply potable water to the southern areas in the Manuka ASYA
proposed for development is to develop sources in the Southeast Mauna Loa ASEA (805) and
transfer water to the Southwest Mauna Loa ASEA. As described in the 2004 Kau to South Kona
Water Master Plan, several water transfer alternatives might be considered, including different
combinations of development of wells north of South Point and extension of the DWS
Waiohinu-Naalehu System, construction of a pipeline to deliver such sources to South Point, and
standpipes north of the South Point area to reduce water hauler distances.
Water transfer may also be considered to supply nonpotable water for agricultural purposes.
Should DWS abandon tunnel sources in the Naalehu Aquifer System, which may be under
surface water influence, in favor of groundwater sources due to Federal Safe Drinking Water Act
requirements, these sources may be available to transfer to areas proposed for development in the
Manuka ASYA.
806.5.2.1.2 Alternative Water Resource Enhancement Measures
806.5.2.1.2.1 Rainwater Catchment Systems
Some of the area within the sector area proposed for development receives sufficient rainfall to
support catchment, however most do not. Notably, the Ocean View area, which relies on
individual rainwater catchment systems, receives less than 60 inches of rainfall per year, which is
generally less than adequate. Evidence of this inadequacy is Ocean View’s frequent dependency
on hauled water.
Rainwater catchment systems may be used to supplement nonpotable sources. Runoff could be
to collected from land and road areas and stored in ponds, which in turn could be used for
irrigation or fire protection.
806.5.2.1.2.2 Wastewater Reclamation
Wastewater reclamation facilities can only be implemented if a sanitary collection system and a
wastewater treatment facility exist. Currently, only areas in the Kealakekua ASYA have such
systems in place. In future development areas, community planning may structure land uses
requiring nonpotable water around the placement of a wastewater treatment and wastewater
reclamation facility. Wastewater flows would need to be large enough to justify the cost of a
806 Southwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
reclamation facility. Projections indicate the population of the sector area is expected to grow by
8,000 over the next 20 years; therefore, this alternative might become feasible.
806.5.2.1.2.3 Desalination
Although costly, desalination of brackish groundwater might be one of the more cost-effective
alternatives in southern areas of the Manuka ASYA. Chloride content in the Kahuku Well was
reported at 300 ppm, which is promising. Desalination of water with such low chlorides would
require significantly less energy.
806.5.2.2 Demand-Side Management
806.5.2.2.1 Development Density Control
Full build-out demands associated with LUPAG maximum density are over ten times greater
than that of Zoning. The Ocean View area is classified as “Rural” in the LUPAG. The area
consists of over 12,000 subdivided lots, almost all of which are one acre in size; therefore, the
density assumption of 1 lot per acre for LUPAG “Rural” designations is consistent.
Urban LUPAG areas only exist in the Kealakekua ASYA, where potable water sources are
available. Water requirements associated with development of these areas to the maximum
density area less than 10 mgd, which is less than 5 percent of the SY; therefore, development
density control in these locations is not necessary.
806.5.2.2.2 Water Conservation
The average water consumption per connection to the DWS system in the Southwest Mauna Loa
ASEA is over 500 gpd per connection, which is higher than the island average; however, the
average potable water consumption per capita from all sources is estimated at 145 gpd, which is
exactly the island average. Water conservation should continue; however, strict demand-side
conservation practices do not need to be implemented. Some measures include voluntary water
conservation during dry periods, education programs, and requirement for more efficient
landscaping practices.
806.5.3 Recommended Alternatives
Exploration and development of high-level groundwater sources should continue as the primary
source to meet potable water requirements in the Kealakekua ASYA, and for potential transfer to
the Hualalai ASEA (809).
DWS should strive to reduce the average consumption per connection closer to the island
average. Although sources are readily available, conservation efforts would make available
more source water to transfer to the Hualalai ASEA (809).
806 Southwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Alternatives to supply potable and nonpotable water to the area in the Manuka ASYA proposed
for development should be considered in conjunction with public input to determine near term
and far term water supply strategies.
807 Northwest Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
807 NORTHWEST MAUNA LOA AQUIFER SECTOR AREA
807.1 SECTOR AREA PROFILE
807.1.1 General
The Northwest Mauna Loa Aquifer Sector Area (ASEA) includes the Anaehoomalu [80701]
Aquifer System Area (ASYA). It extends from the summit of Mauna Loa, northwest to the
western shores of Anaehoomalu; and spans three districts, capturing the southern coastal portion
of the South Kohala District, the northeastern portion of the North Kona District and the southern
portion of the Hamakua District.
Average rainfall ranges from 10 inches along the coast to 45 inches in the low-lying areas
between Mauna Kea and Mauna Loa. The sustainable yield is 30 mgd.
807.1.2 Economy and Population
807.1.2.1 Economy
Tourism has become the leading economic industry in South Kohala. Two of South Kohala’s
three luxury resorts lie within the Northwest Mauna Loa ASEA. The Mauna Lani Resort
includes a hotel and several condominium resorts and villas. The Waikoloa Resort includes two
hotels and six condominium resorts on 1,150 acres. Both resorts sport two golf courses and other
amenities.
The Pohakuloa Military Training Area (PTA) is also located in the saddle area between Mauna
Kea and Mauna Loa within the southern portion of the sector area. The PTA consists of 108,863
acres, however much of this is designated as a conservation district. As the largest training area
in Hawaii, Pohakuloa can be used to accomplish nearly all of the varying types of training
required by the military forces. A support area of 600 acres containing logistic and
administrative facilities plus quarters for approximately 2,000 troops is located to the north at the
base of Mauna Kea.
807.1.2.2 Population
Nearly all of the population contributing to the demands from the sector area is within the South
Kohala District. The growth in tourism has followed the dramatic increase in the population of
South Kohala over the past 30 years; and as a result, South Kohala enjoyed the lowest
unemployment rate and the highest median income on the island in 1997.
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Table 807-1: Historical Population
1980 1990 2000
1980-90
% Change
1990-2000
% Change
173 344 494 98.8 43.6
Data Source: 2000 U.S. Census
Data redistributed and evaluated for Northwest Mauna Loa ASEA
Table 807-2: Population Projection
Growth
Rate 2000 2005 2010 2015 2020
2000-10
% Change
2010-20
% Change
A – Low 494 587 678 781 901 37.2 32.9
B – Medium 494 589 684 793 919 38.5 34.4
C – High 494 614 727 855 1,002 47.2 37.8
Data Source: County General Plan, February 2005
Data redistributed and evaluated for Northwest Mauna Loa ASEA
807.1.3 Land Use
807.1.3.1 Hawaii County General Plan
The Hawaii County General Plan Land Use Pattern Allocation Guide Map (LUPAG) for the
sector area is shown on Figure 807-1. The estimated land use allocation acreage for each
LUPAG designation within the Sector is listed in Table 807-3.
Table 807-3: LUPAG Map Estimated Land Use Allocation Acreage – Northwest Mauna
Loa Aquifer Sector Area
LAND USE PATTERN ACREAGE
% of
TOTAL
High Density Urban 0 0
Medium Density Urban 99 0.05
Low Density Urban 343 0.17
Industrial 155 0.08
Important Agricultural Land 2,079 1.02
Extensive Agriculture 23,100 11.31
Orchard 0 0
Rural 44 0.02
Resort/Resort Node 2,551 1.25
Open 5,472 2.68
Conservation 163,573 80.08
Urban Expansion 6,842 3.35
University Use 0 0
TOTAL 204,257 100.00
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
The water utility courses of action for South Kohala in the Hawaii County General Plan relevant
to the Northwest Mauna Loa ASEA are as follows:
(a) Seek alternative sources of water for the Lalamilo system.
(b) Improve and replace inadequate distribution mains and steel tanks.
807.1.3.2 Hawaii County Zoning
Hawaii County Zoning for the sector area is shown on Figure 807-2. The estimated land use
allocation acreage for each zoning class within the sector area is listed in Table 807-4.
Table 807-4: County Zoning Estimated Class Allocation Acreage – Northwest Mauna Loa
Aquifer Sector Area
ZONING CLASS ACREAGE
% of
TOTAL
Single Family Residential 349 0.17
Multi-Family Residential
(including duplex) 1,222 0.60
Residential-Commercial Mixed Use 0 0
Resort 234 0.11
Commercial 127 0.06
Industrial 2 0.00
Industrial-Commercial Mixed 0 0
Family Agriculture 0 0
Residential Agriculture 868 0.42
Agriculture 32,869 16.09
Open 60,274 29.51
Project District 0 0
Forest Reserve 107,774 52.76
(road) 537 0.26
TOTAL 204,254 100.00
807.2 AVAILABLE WATER RESOURCES
807.2.1 Ground Water
The Northwest Mauna Loa ASEA has a sustainable yield of 30 mgd. According to the CWRM
database, there are 19 production wells in the sector, including 11 irrigation, 1 industrial, and 7
other. Refer to Appendix B for this database. Figure 807-3 shows the well locations.
807.2.2 Surface Water
There are no declared stream diversions in the sector area in CRWM database.
807 Northwest Mauna Loa Aquifer Sector Area
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807.2.3 Reclaimed Wastewater
There are 2 wastewater reclamation facilities (WWRF) in the study area. Table 807-5 lists the
WWRF, reclaimed water classification, facility treatment capacity, current reuse amount, and
current application.
Table 807-5: Wastewater Reclamation Facilities – Northwest Mauna Loa Aquifer Sector
Area
Wastewater
Reclamation Facility
Reclaimed
Water
Classification
WWRF
Capacity
(MGD)
Current
Reuse
Amount
(MGD)
Irrigation Application
Waikoloa Beach
Resort WRF R-2 1.3 0.5 Beach Resort/Golf Course
Mauna Lani WWRF R-2 0.75 0.25 Nursery/Sod Farm/Composting
807.3 EXISTING WATER USE
807.3.1 General
The total estimated average water use within the Northwest Mauna Loa ASEA from November
2004 through October 2005 based on DWS meter data, CWRM pumpage data, available GIS
data, SWPP estimates, and estimated reclaimed wastewater usage is listed in Table 807-6 and
summarized in Figure 807-5 in accordance with CWRM categories; and indicate the quantities
supplied excluding agricultural demands, and the quantities supplied including worst case
agricultural demands (as described in Chapter 2) by the DWS system and non-DWS systems.
Table 807-6: Existing Water Use by Categories – Northwest Mauna Loa Aquifer Sector
Area
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.00 0.0 0.0
Industrial 0.00 0.0 0.0
Irrigation 5.05 63.3 62.0
Reclaimed WW 0.75 9.4 9.2
Agriculture 0.18 0.0 2.2
Military 0.03 0.4 0.4
Municipal
DWS System 2.14 26.9 26.3
Private Public WS 0.00 0.0 0.0
Total without Ag* 7.97 100.0
Total with Ag* 8.15 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
807 Northwest Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 807-3: Well and Tunnel Location
MAP CURRENTLY NOT AVAILABLE ON-LINE
807 Northwest Mauna Loa Aquifer Sector Area
Page 807-11
Hawaii County
Water Use and Development Plan Update
Figure 807-4: Streams & Diversions
MAP CURRENTLY NOT AVAILABLE ON-LINE
807 Northwest Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 807-5: Existing Water Use by Categories – Northwest Mauna Loa Aquifer Sector
Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 807-6 generally shows the service area for the various water systems and indicates the
extent of the DWS water system.
807.3.2 Domestic Use
Domestic use or water use by individual households is assumed to be supplied by private
individual rainwater catchment systems. However, there is no evidence of such usage within the
sector.
807.3.3 Industrial Use
There is no reported industrial usage in the CWRM well database.
807.3.4 Irrigation Use
Irrigation accounts for nearly two-thirds of the water used in the sector area, and is based on
pumpage reported for private wells categorized by CWRM as irrigation wells and reclaimed
water use as indicated in previously Table 807-6. Table 807-7 indicates the average for private
irrigation well pumpage reported to CWRM.
Domestic 0.0%
Industrial 0.0%
Irrigation 63.3%
Irrigation (Recl'd
WW) 9.4%
Agriculture 0.0%
Military 0.4%
Municipal
(Non-DWS) 0.0%
Municipal
(DWS) 26.9%
Domestic 0.0%
Industrial 0.0%
Irrigation 62.0%
Irrigation (Recl'd
WW) 9.2%
Agriculture 2.2%
Military 0.4%
Municipal
(Non-DWS) 0.0%
Municipal
(DWS) 26.3%
w/o Agricultural Water Use*with Agricultural Water Use*
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Table 807-7: Private Irrigation Well Pumpage
Private Irrigation Irrigation Well Pumpage (mgd)
Mauna Lani Resort 1.56
Waikoloa 2.56
Parker Ranch 0.83
TOTAL 5.05
The Mauna Lani Resort maintains seven brackish water wells for golf course irrigation, four of
which are located in the Northwest Mauna Loa ASEA.
The Waikoloa Resort lands were purchased in 1968 from Parker Ranch by Boise Cascade. The
lands are split between the Northwest Mauna Loa ASEA and the West Mauna Kea ASEA (803),
with the higher elevation lands above the beach resort used for residential development within
the former and the oceanfront lands used for resort hotel development within the latter. Six wells
located within the Northwest Mauna Loa ASEA provide brackish water for golf course
irrigation.
807.3.5 Agricultural Use
There is no agricultural usage from known sources in the sector area.
807.3.6 Military Use
One of the county’s two military water systems is located at the Pohakuloa Training Area (PTA)
in the saddle region between Mauna Kea and Mauna Loa. Not including the small permanent
staff, the population of this military training camp fluctuates with the number of troops involved
in the training being held at a specific time and water demand fluctuates accordingly. For
example, the population can increase up to 5,000 troops for major exercises, usually held during
May to October. The average day demand estimated in the Hawaii SWPP is 30,000 gpd with a
peak during training periods of 80,000 gpd. The system obtains its water from the Mauna Kea
State Park Water System, which is supplied by five springs in the West Mauna Kea ASEA.
During periods of high consumption, additional water is hauled by private and military tankers
from municipal systems either in Hilo or Kamuela.
807.3.7 Municipal Use
Municipal use can be subcategorized into the other water use categories, namely Domestic,
Industrial, Irrigation, Agriculture, and Military, if detailed information is available.
807.3.7.1 County Water Systems
The Lalamilo Water System described in Chapter 803 services the Mauna Lani Resort. DWS
records indicate that the Mauna Lani Bay Hotel is one of the largest single water users served by
DWS.
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
DWS water use is subcategorized in Table 807-8 to the extent possible based on available meter
data and is depicted in Figure 807-7. “Other Municipal” includes facilities such as schools, and
various commercial, government, medical and nonprofit entities which have mixed water use and
cannot be specifically allocated to the other categories.
Table 807-8: DWS Existing Water Use by Categories – Northwest Mauna Loa Aquifer
Sector Area
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 0.75 34.9
Industrial 0.00 0.2
Irrigation 0.17 8.1
Agriculture 0.00 0.0
Military 0.00 0.0
Other Municipal 1.22 56.8
Total 2.14 100.0
Figure 807-7: DWS Existing Water Use by Categories – Northwest Mauna Loa Aquifer
Sector Area
Domestic 34.9%
Industrial 0.2%
Irrigation 8.1%
Agriculture 0.0%
Military 0.0%
Other Municipal
56.8%
807.3.7.2 State Water Systems
There are no State water systems in the Northwest Mauna Loa ASEA.
807 Northwest Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
807.3.7.3 Federal Water Systems
The PTA Water System described in Section 807.3.6 is the only Federal water system in the
Northwest Mauna Loa ASEA.
807.3.7.4 Private Public Water Systems
Potable water wells supplying the Waikoloa Water System described in Chapter 803 are located
in the West Mauna Kea ASEA (803); however, the water system service area extends into the
Northwest Mauna Loa ASEA to the Waikoloa Resort.
807.3.8 Water Use by Resource
807.3.8.1 Ground Water
Table 807-9 summarizes the current production, potential production (16 and 24 hour operation),
sustainable yield (SY), and percentage of SY for the various productions calculated. Current
production is represented by the highest 12-month moving average (MAV) or the highest annual
average yield calculated from the actual pumpage data. Potential well production is based on
installed pump capacities, and calculated for both 16 hours of operation a day and 24 hours of
operation a day. Data is based on pumpage data reported to CWRM.
Talbe 807-9: Sustainable Yield – Northwest Mauna Loa Aquifer Sector Area
Sys Code System Area
High
12-Month
MAV (MGD)
Potential
16 -Hour
Production (MGD)
Potential
24-Hour
Production (MGD) SY (MGD)
High
12-Month
MAV
SY (%)
Potential
16-Hour
Production
SY (%)
Potential
24-Hour
Production
SY (%)
4.13 10.61 15.91 30 13.77 35.36 53.03
80701 Anaehoomalu 4.13 10.61 15.91 30 13.77 35.36 53.03
807.3.8.2 Surface Water
There are no known surface water uses in the Northwest Mauna Loa ASEA.
807.3.8.3 Rainwater Catchment
Water consumption calculated for developed parcels that are not supplied by groundwater or
surface water is assumed to be supplied by rainwater catchment. According to available GIS
information, no such parcels exist within the sector area.
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
807.3.8.4 Reclaimed Wastewater
Reclaimed wastewater from the two wastewater treatment plants within the Northwest Mauna
Loa ASEA is used for golf course, landscaping, nursery, sod farm and compost irrigation. Refer
to Table 807-5 presented earlier.
807.4 FUTURE WATER NEEDS
807.4.1 General
Table 807-10 summarizes the LUPAG, Zoning and 5-year incremental water demand projection
scenarios for the total aquifer sector area and the individual aquifer system area. The sustainable
yield (SY) is presented to draw comparisons.
Table 807-10: Summary of Demand Projections
Growth Rate B Demand Projections (mgd)Without
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total N.W. Mauna Loa ASEA 30 81.7 11.0 8.0 9.3 10.7 12.4 14.4
80701 – Anaehoomalu ASYA 30 81.7 11.0 8.0 9.3 10.7 12.4 14.4
Growth Rate B Demand Projections (mgd)With
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total N.W. Mauna Loa ASEA 30 88.7 18.1 8.2 9.5 11.0 12.7 14.7
80701 – Anaehoomalu ASYA 30 88.7 18.1 8.2 9.5 11.0 12.7 14.7
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
There is only one aquifer system area within the Northwest Mauna Loa ASEA; therefore,
demands presented by aquifer sector area and by aquifer system area are one in the same.
807.4.2 Full Build-Out Water Demand Projections
The full build-out water demand projections based on the General Plan and County Zoning for
the Northwest Mauna Loa ASEA are listed in Tables 807-11 and 807-12, and reflect refinement
as discussed below. Each land use class is associated with the most appropriate CWRM water
use category.
807 Northwest Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Table 807-11: Hawaii County General Plan Full Build-Out Water Demand Projection –
Northwest Mauna Loa Aquifer Sector Area
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 3.4
Urban Expansion Domestic/Irrigation/Municipal 34.2
Resort Irrigation/Municipal 43.4
Industrial Industrial 0.6
Agriculture Agriculture 7.1
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 0.0
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 81.7
TOTAL w/ Ag* 88.7
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 807-12: County Zoning Full Build-Out Water Demand Projection – Northwest
Mauna Loa Aquifer Sector Area
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 7.3
Resort Irrigation/Municipal 3.3
Commercial Municipal 0.4
Industrial Industrial 0.1
Agriculture Agriculture 7.1
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 11.0
TOTAL w/ Ag* 18.1
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
807.4.2.1 Refine Land Use Based Projection
807.4.2.1.1 State Water Projects Plan
There is only one State Water Project within the Northwest Mauna Loa ASEA. The projected
demand required by the Puako Boat Ramp in the year 2020 is 0.005 mgd of potable water.
807.4.2.1.2 State Department of Hawaiian Home Lands
There are no tracts of land owned by the DHHL within the Northwest Mauna Loa ASEA.
807.4.2.1.3 Agricultural Water Use and Development Plan
807 Northwest Mauna Loa Aquifer Sector Area
Page 807-21
Hawaii County
Water Use and Development Plan Update
There is no information available in the AWUDP specific to activity within the Northwest
Mauna Loa ASEA to further refine projections.
807.4.3 Water Use Unit Rates
Water use unit rates are based on the Water System Standards as discussed in Chapter 1, and
single family residential (Low Density Urban category of the General Plan and RS-7.5 and
greater or Single-Family Residential categories of one lot per at least 7,500 square foot of
County Zoning) consumption is 2.5 units per lot based on historical consumption data.
807.4.4 5-Year Incremental Water Demand Projection to the Year 2025
The following section presents 5-year incremental water demand projections to the year 2025 for
the Northwest Mauna Loa ASEA. The projected low, medium, and high growth rates are listed
in Table 807-13, and are graphed in Figure 807-8. Potable and nonpotable water demands are
also differentiated.
Figure 807-9 illustrates the magnitude of the sustainable yield, both LUPAG and Zoning full
build-out water use, and water use projection through the year 2025 focusing on Medium Growth
Rate B. Figure 807-10 shows the breakdown of water demand projections by CWRM categories
through the year 2025. Table 807-14 summarizes these figures.
Table 807-13: Water Demand Projection – Northwest Mauna Loa Aquifer Sector Area
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 8.0 9.2 10.6 12.2 14.1 8.2 9.4 10.8 12.5 14.4
Potable 2.2 2.5 2.9 3.3 3.8 2.2 2.5 2.9 3.3 3.8
Nonpotable 5.8 6.7 7.7 8.9 10.3 6.0 6.9 8.0 9.2 10.6
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 8.0 9.3 10.7 12.4 14.4 8.2 9.5 11.0 12.7 14.7
Potable 2.2 2.5 2.9 3.4 3.9 2.2 2.5 2.9 3.4 3.9
Nonpotable 5.8 6.7 7.8 9.0 10.5 6.0 6.9 8.1 9.3 10.8
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 8.0 9.4 11.1 13.0 15.2 8.2 9.7 11.4 13.3 15.6
Potable 2.2 2.6 3.0 3.5 4.2 2.2 2.6 3.0 3.5 4.2
Nonpotable 5.8 6.9 8.1 9.5 11.1 6.0 7.1 8.3 9.8 11.4
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Figure 807-8: Water Demand Projection Summary – Northwest Mauna Loa Aquifer Sector
Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 807-14: Medium Growth Rate B Water Demand Projection by Category – Northwest
Mauna Loa Aquifer Sector Area
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 8.0 9.3 10.7 12.4 14.4
Total with Ag* 8.2 9.5 11.0 12.7 14.7
Domestic 0.0 0.0 0.0 0.0 0.0
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 5.8 6.7 7.8 9.0 10.5
Agriculture 0.2 0.2 0.2 0.3 0.3
Military 0.0 0.0 0.0 0.0 0.1
Municipal 2.1 2.5 2.9 3.3 3.9
Potable 2.2 2.5 2.9 3.4 3.9
Nonpotable w/o Ag* 5.8 6.7 7.8 9.0 10.5
Nonpotable w/ Ag* 6.0 6.9 8.1 9.3 10.8
DWS 2.1 2.5 2.9 3.3 3.9
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
2005 2010 2015 2020 2025
YearDemand (mgd)Total w/o Ag*
Potable
Nonpotable w/o Ag*
Total w/ Ag*
Potable
Nonpotable w/ Ag*
LEGEND: Growth Rate A Growth Rate B Growth Rate C
807 Northwest Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 807-9: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Northwest Mauna Loa Aquifer Sector Area
0
10
20
30
40
50
60
70
80
90
100
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
LUPAG = 82–89
SY = 30
Zoning = 11–18
Legend*, **
807 Northwest Mauna Loa Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 807-10: Medium Growth Rate B Water Demand Projection by Category –
Northwest Mauna Loa Aquifer Sector Area
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
807.4.5 DWS Historical Water Consumption Data Projections
DWS supplied water consumption was projected in 5-year increments to the year 2025 based on
DWS historical water system consumption data from 1970 to 2003, as shown on Figure 807-11.
Legend*, **
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
Figure 807-11: DWS Water Demand Projection – Northwest Mauna Loa Aquifer Sector
Area
Lalamilo Water System
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
1970 1980 1990 2000 2010 2020mgdHistorical Projected
Year 2005: 3.76 mgd
Year 2010: 4.30 mgd
Year 2015: 4.85 mgd
Year 2020: 5.40 mgd
Year 2025: 5.94 mgd
Historical data provided by RW Beck, Inc.
Projections based on historical DWS water consumption data cannot be compared to projections
based on population growth rate, because the Lalamilo Water System spans the Northwest
Mauna Loa and West Mauna Kea (803) ASEAs. The projected rate of growth of the future
population is slightly higher than the rate of increase based on historical consumption.
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
807.5 RESOURCE AND FACILITY RECOMMENDATIONS
807.5.1 Water Source Adequacy
807.5.1.1 Full Build-Out
The full development to the maximum density of the County General Plan land use within the
Northwest Mauna Loa ASEA cannot be sustained by water sources in the sector area if
agricultural demands are not included. Full build-out water demands based on LUPAG are
nearly three times the sustainable yield of sector area. The existing Zoning requires
approximately one third of the existing sustainable yield. If worst case agricultural demands are
included, the LUPAG demand is three times the SY, and the Zoning demand is 60 percent of the
SY.
807.5.1.2 Twenty-Year Projection
Existing demands are less than 30 percent of the SY, and 20-year projected demands are close to
50 percent of the SY.
807.5.2 Source Development Requirements
807.5.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, are evaluated to meet projected water demands.
807.5.2.1.1 Conventional Water Resource Measures
807.5.2.1.1.1 Ground Water
According to the 1990 Water Resources Protection Plan, the basal lens extends at least five
miles inland, and approximately 10 miles from the coast high level water may occur at great
depth. Due to the remoteness and high cost of developing the high level aquifer, exploitation of
this resource to supply existing developed areas and adjacent expansion areas is not likely. High
level water may be utilized should localized development occur in areas over the high-level
aquifer.
The basal aquifer is thin in most accessible areas which would prevent development of potable
water. However, additional brackish water may be developed to some extent as evidenced by the
irrigation wells located along Queen Kaahumanu Highway. Care should be exercised to avoid
overdrawing which may lead to intrusion of saltwater in the wells. Chloride levels should be
continuously monitored.
807.5.2.1.1.2 Surface Water
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
There are no perennial streams nor are there any registered stream diversions in the Northwest
Mauna Loa ASEA, therefore surface water is not a viable water resource enhancement measure.
807.5.2.1.1.3 Water Transfer
Currently, all potable water is obtained from the West Mauna Kea ASEA (803) by water transfer
via the DWS Lalamilo Water System, which supplies the Mauna Lani Resort, and the private
Waikoloa System, which supplies the Waikoloa Resort. An undetermined quantity of water is
also transferred into ASEA 803 from the Kohala ASEA (801) through the Waimea SystemDue to
the difficulty in developing potable sources in the Northwest Mauna Loa ASEA, additional water
transfer from the ASEA 803 will continue ; however, the feasibility of developing additional
sources in the ASEA 803 for transfer needs to be examined further.
807.5.2.1.2 Alternative Water Resource Enhancement Measures
807.5.2.1.2.1 Rainwater Catchment Systems
The Northwest Mauna Loa ASEA is the driest on the island. Most of the sector area receives
between 10 and 30 inches of rainfall per year, which is not sufficient to support rainwater
catchment systems. This is not considered a viable alternative.
807.5.2.1.2.2 Wastewater Reclamation
The two existing wastewater reclamation facilities currently reuse 0.75 mgd but are expandable
to 2.05 mgd. Reuse of the up to 75% of the capacity of a WWRF is generally the maximum
percentage achievable. The facilities use wastewater from the two major resort developments,
Mauna Lani and Waikoloa, which together account for nearly all of the potable water used in the
sector area. Increase in reclaimed wastewater production is therefore limited by the amount of
water used by and hence growth of the two resorts. However, reclaimed wastewater is currently
used for irrigation purposes within the resort complexes, and since increased irrigation uses are
expected to follow additional development of the resorts, expansion of the existing facilities is a
logical choice.
807.5.2.1.2.3 Desalination
Desalination of groundwater from brackish wells in the lower lying areas may be considered.
The chloride content of the existing irrigation wells is generally less than 1,000 ppm, indicating
that the brackish water from the aquifer is suitable for desalination. However, there are limits to
the amount of water that can be drawn without degrading the water table. As in the West Mauna
Kea ASEA (803), the service area would be limited to the coastal regions, such as in the vicinity
of the Mauna Lani and the Waikoloa Resorts.
807.5.2.2 Demand-Side Management
807.5.2.2.1 Development Density Control
807 Northwest Mauna Loa Aquifer Sector Area
Page 807-28
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Water Use and Development Plan Update
The water requirements of full-build out under maximum density LUPAG are over eight times
greater than those of legally developable land under Zoning, largely due to the difference in areas
of land classified as “Resort” and “Urban/Residential.” Proposed land uses according to the
General Plan should therefore be examined in greater detail. In particular, there is nearly 7,000
acres designated as “Urban Expansion.” Control of the density of these future expansion areas
could conserve a significant quantity of water.
807.5.2.2.2 Water Conservation
Water use unit rates for users on the DWS Water System in the sector area are the highest on the
island. Accounts classified as “Residential” use an average of over 2,700 gpd per connection,
and the average usage for all accounts is over 6,300 gpd per connection, although this average is
likely greatly skewed by the large hotel and resort users. The per capita potable water
consumption unit rate is not a reliable indicator of average water usage since nearly all of the
potable water demand is from the transient population. Nonetheless, existing residential usage is
over six times the island average. Both resort complexes include private villa and mansion style
homes that possibly use potable water for landscaping.
Water purveyors could easier justify implementing conservation measures in the Northwest
Mauna Loa ASEA than any other sector area, because it is the driest sector area on the island.
Financial conservation measures, such as a rate structure incorporating higher unit costs for
increased usage, may not be effective, because many of the end users are in a higher income
bracket and are not likely to be deterred by cost. Water conservation measures such as water
restrictions during drier and/or warmer periods, and implementation of requirements for more
efficient irrigation practices would be most effective.
807.5.3 Recommended Alternatives
The lack of conventional water sources places the emphasis on water conservation. Average
usage in the Northwest Mauna Loa ASEA is the highest on the island; the demand can be
reduced considerably by lowering per unit usage rates closer to the island average.
Transfer of potable water from the West Mauna Kea ASEA (803) to the Northwest Mauna Loa
ASEA must continue, and may be increased in the near term to supply the projected demands.
However, existing sources in the ASEA 803 will not be adequate past 2010.
Brackish groundwater should be developed to satisfy nonpotable needs, but should be preceded
by studies evaluating the potential of brackish water sources.
Wastewater reclamation should be emphasized due to the limited availability of groundwater and
non-existence of surface water sources. It may be prudent for County Planning to consider
linking additional development in the vicinity of the resort complexes that require irrigation to
increase in wastewater reclamation capacity to ensure that nonpotable water demands are met by
nonpotable sources. Because of the compactness of the two major resort developments, studies
should be undertaken to investigate the possibility of combining reclaimed wastewater and
807 Northwest Mauna Loa Aquifer Sector Area
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Water Use and Development Plan Update
brackish groundwater sources into a nonpotable water system to satisfy the nonpotable needs.
This, along with other alternatives consistent with the concept of using the highest quality water
for the highest intended use, should be considered.
In light of the fact that the sustainable yield is not fully developable, and maximum density
LUPAG full build-out demands cannot be sustained by existing sources, it is important that a
long-range water plan for the Northwest Mauna Loa ASEA be developed, in which all of the
recommended alternatives are evaluated.
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
808 KILAUEA AQUIFER SECTOR AREA
808.1 SECTOR AREA PROFILE
808.1.1 General
The Kilauea Aquifer Sector Area (ASEA) includes the Pahoa [80801], Kalapana [80802], Hilina
[80803], and Keaiwa [80804] Aquifer System Areas (ASYA). It captures most of the Puna
District and the southeastern portion of the Kau District, and extends along most of the island’s
southeastern coastline as far south as Kuhua Bay outside Punaluu. The sector area includes most
of the Kilauea Crater and Hawaii Volcanoes National Park.
Average annual rainfall in coastal areas ranges from less than 40 inches along the dryer, southern
coastline to 118 inches along the windward or eastern coastline. Average annual rainfall at the
summit of Kilauea is as low as 20 inches, and in the Mountain View area is almost 200 inches.
The Pahoa ASYA has by far the highest SY of the four system areas at 435 mgd, followed by the
Kalapana ASYA at 157 mgd, the Keaiwa ASYA at 17 mgd, and the Hilina ASYA at 9 mgd. The
total sustainable yield of the Kilauea ASEA is 618 mgd.
808.1.2 Economy and Population
808.1.2.1 Economy
Agriculture is the primary economic function in the Puna District. Papayas in the Kapoho area,
flowers in the Pahoa and Kapoho areas, and bananas are the principal products. Truck farming
in the Volcano area is also significant. The majority of the State’s papayas and bananas are
grown in Puna.
There are some tourist attractions in the sector area, including Hawaii Volcanoes National Park;
however, these have had little impact on the economy, evident by the limited number of tourist
accommodations and roadside stands.
The Puna Geothermal Venture (PGV) plant located outside of Kapoho generates 30-MW of
electricity using three geothermal wells. Plans are already under way to expand the facility to
double its output. Currently, PGV employs 30 people. The geothermal industry is promising, as
waste geothermal heat may be used for a variety of different functions, which may attract other
business to the sector area.
808.1.2.2 Population
Nearly all of the population contributing to the demands from the Kilauea ASEA is within the
Puna District. The rate of growth of Puna’s population has slowed, but still ranks as the island’s
highest. The growth can be attributed to the affordability of residences outside of Hilo and the
job opportunities in Hilo. Puna’s status as a “bedroom community” for Hilo is evident from
much slower growth in employment, and the worsening traffic on its roads leading into Hilo.
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Table 808-1: Historical Population
1980 1990 2000
1980-90
% Change
1990-2000
% Change
9,385 16,587 25,007 76.7 50.8
Data Source: 2000 U.S. Census
Data redistributed and evaluated for Kilauea Aquifer Sector Area
Table 808-2: Population Projection
Growth
Rate 2000 2005 2010 2015 2020
2000-10
% Change
2010-20
% Change
A – Low 25,007 28,916 33,688 39,158 45,561 34.7 35.2
B – Medium 25,007 29,009 33,986 39,736 46,471 35.9 36.7
C – High 25,007 30,218 36,116 42,858 50,656 44.4 40.3
Data Source: County General Plan, February 2005
Data redistributed and evaluated for Kilauea Aquifer Sector Area
808.1.3 Land Use
808.1.3.1 Hawaii County General Plan
The Hawaii County General Plan Land Use Pattern Allocation Guide Map (LUPAG) for the
Kilauea ASEA is shown on Figure 808-1. The estimated land use allocation acreage for each
LUPAG designation within the sector area is listed in Table 808-3.
Table 808-3: LUPAG Map Estimated Land Use Allocation Acreage – Kilauea Aquifer
Sector Area
LAND USE PATTERN ACREAGE
% of
TOTAL
High Density Urban 0 0
Medium Density Urban 410 0.1
Low Density Urban 6,218 1.8
Industrial 42 0.0
Important Agricultural Land 26,719 7.5
Extensive Agriculture 93,911 26.2
Orchard 0 0
Rural 27,211 7.6
Resort/Resort Node 4 0.0
Open 2,587 0.7
Conservation 199,697 55.8
Urban Expansion 1,072 0.3
University Use 0 0
TOTAL 357,871 100.0
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
The water utility courses of action for Puna in the Hawaii County General Plan relevant to the
Kilauea ASEA are as follows:
(a) Continue to improve inadequate water system facilities.
(b) Water source investigation and exploration should be continued in order to provide
service for anticipated needs.
(c) Investigate additional groundwater sources in the Olaa area.
(d) Investigate alternative means to finance the extension to subdivisions that rely on
catchment.
808.1.3.2 Hawaii County Zoning
Hawaii County Zoning for the Kilauea ASEA is shown on Figure 808-2. The estimated land use
allocation acreage for each zoning class within the sector area is listed in Table 808-4.
Table 808-4: County Zoning Estimated Class Allocation Acreage – Kilauea Aquifer Sector
Area
ZONING CLASS ACREAGE
% of
TOTAL
Single Family Residential 2,041 0.6
Multi-Family Residential
(including duplex) 4 0.0
Residential-Commercial Mixed Use 0 0
Resort 1 0.0
Commercial 40 0.0
Industrial 0 0
Industrial-Commercial Mixed 9 0.0
Family Agriculture 8 0.0
Residential Agriculture 137 0.0
Agriculture 179,106 50.1
Open 139,914 39.1
Project District 0 0
Forest Reserve 31,857 8.9
(road) 4,571 1.3
TOTAL 357,688 100.0
808.2 AVAILABLE WATER RESOURCES
808.2.1 Ground Water
Kilauea ASEA has a sustainable yield of 618 mgd. According to the CWRM database, there are
45 production wells in the sector, including 8 municipal, 8 irrigation, 19 domestic, and 10 other.
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
There are also 19 wells drilled and categorized as “unused”. Refer to Appendix B for this
database. Figure 808-3 shows the well locations.
808.2.2 Surface Water
There are no perennial streams in the sector area. There is 1 declared stream diversion in
CRWM database listed in Table 808-5 and shown on Figure 808-4.
Table 808-5: Stream Diversions – Kilauea Aquifer Sector Area
FILE REFERENCE TMK STREAM NAME
MALU AINA FARM 1-7-002:002 Unnamed/ Unmapped Stream diversion, waterway from Malu Aina Stream. See
also two new entries for declarant.
808.2.3 Reclaimed Wastewater
There are no wastewater reclamation facilities within the Kilauea ASEA.
808.3 EXISTING WATER USE
808.3.1 General
The total estimated average water use within the Kilauea ASEA from November 2004 through
October 2005 based on DWS meter data, available GIS data, DOH records, and CWRM
pumpage data is listed in Table 808-6. Table 808-6 and Figure 808-5 summarize water use in
accordance with CWRM categories and indicate the quantities supplied excluding agricultural
demands, and the quantities supplied including worst case agricultural demands (as described in
Chapter 2) by the DWS system, non-DWS systems.
808 Kilauea Aquifer Sector Area
Page 808-9
Hawaii County
Water Use and Development Plan Update
Figure 808-3: Well and Tunnel Location
MAP CURRENTLY NOT AVAILABLE ON-LINE
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 808-4: Streams & Diversions
MAP CURRENTLY NOT AVAILABLE ON-LINE
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Table 808-6: Existing Water Use by Categories – Kilauea Aquifer Sector Area
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 2.69 61.6 40.9
Industrial 0.00 0.0 0.0
Irrigation 0.00 0.0 0.0
Reclaimed WW 0.00 0.0 0.0
Agriculture 2.22 0.0 33.7
Military 0.00 0.0 0.0
Municipal
DWS System 0.70 16.0 10.6
Private Public WS 0.98 22.4 14.8
Total without Ag* 4.37 100.0
Total with Ag* 6.58 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 808-5: Existing Water Use by Categories – Kilauea Aquifer Sector Area
Figure 808-6 generally shows the service area for the various water systems and indicates the
extent of the DWS water system.
808.3.2 Domestic Use
Domestic use or water use by individual households is assumed to be supplied by private
individual rainwater catchment systems or private wells. Based on available GIS data, there are
6,668 such parcels which would serve an estimated 18,000 people or nearly two-thirds of the
Domestic 61.6%Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 22.4%
Municipal
(DWS) 16.0%
Domestic 40.9%
Industrial 0.0%
Irrigation 0.0%
Irrigation (Recl'd
WW) 0.0%
Agriculture 33.7%
Military 0.0%
Municipal
(Non-DWS) 14.8%Municipal
(DWS) 10.6%
with Agricultural Water Use* w/o Agricultural Water Use*
808 Kilauea Aquifer Sector Area
Page 808-14
Hawaii County
Water Use and Development Plan Update
sector area population. The estimated demand from rainwater catchment usage of 2.7 mgd is by
far the most of all sector areas on the island. None of the 19 wells in the CWRM database
classified as “Domestic” have reported pumpage.
808.3.3 Industrial Use
There are no wells classified as “Industrial” in the CWRM database.
Puna Geothermal Venture has two wells classified as “Other” and one well classified as
“Observation,” which are used as monitoring wells to conduct chemical analyses on the
groundwater twice a year. PGV also has three production wells which extract geothermal fluid
and three injection wells which return the used fluid. Because the temperature of the fluid is
greater than 150 degrees Fahrenheit, the wells are regulated by the Land Division, Engineering
Branch of the DLNR.
808.3.4 Irrigation Use
There is one golf course in the sector area. The Volcano Golf & Country Club is situated along
Hawaii Belt Road opposite Hawaii Volcanoes National Park. There is no irrigation system;
rainfall in the area is sufficient to maintain the course.
There are no known irrigation uses dedicated other landscaping activities.
808.3.5 Agricultural Use
Although agricultural activity is significant in the sector area, abundant ambient rainfall is
sufficient for most of the agricultural products, such as papayas and bananas. According to
DWS records, a significant portion of the water consumed in the Kapoho and Kalapana Water
Systems is by accounts classified as “Agricultural;” however, altogether this amounts to less than
0.1 mgd.
808.3.6 Military Use
The Kilauea Military Camp is located within the Kilauea ASEA. The camp is a resort facility for
active and retired military personnel and their families, including 90-1, 2 and 3 bedroom cottages
and apartments, and several amenities including restaurants, stores, sports and games. The camp
has 100 full-time employees. DOH records indicate that water is supplied via catchment;
however, details of the system and consumption are not known.
808.3.7 Municipal Use
Municipal use can be subcategorized into the other water use categories, namely Domestic,
Industrial, Irrigation, Agriculture, and Military, if detailed information is available.
808 Kilauea Aquifer Sector Area
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Water Use and Development Plan Update
808.3.7.1 County Water Systems
The DWS has 3 water systems in the Kilauea ASEA.
The Olaa-Mt. View Water System described in Chapter 804 services areas in the Kilauea ASEA
south of Hawaii Belt Road and along Keeau-Pahoa Road to Kaloli Drive. The water system is
connected along Keeau-Pahoa Drive to the Pahoa Water System, allowing water to flow in either
direction.
The Pahoa Water System obtains its water from two wells at Keonepoko Nui and two wells at
the Pahoa well field. Both sources have good quality water with chloride content between 4 and
27 ppm. The water system services six operational zones in the Pahoa area using one booster
pump station and four storage tanks.
The Kapoho Water System formerly depended on an infiltration gallery type of well, and now
relies entirely on the Pahoa Water System for its supply. A single tank provides storage for the
water system.
The Kalapana Water System obtains its water supply from two wells located at the southwesterly
edge of Keauohana Forest Reserve near the Pahoa-Kalapana Highway. The water has a
relatively high chloride content of between 107 and 124 ppm. The water system’s service area
runs from the forest reserve along the highway to Kaimu area and along the coastal road to
Queens Bath area. However, the lava flow has buried long segments of the highway and
watermains and destroyed many residences in the area. Presently, two operational zones are
serviced using two storage tanks. There are no booster pump stations in the water system.
DWS water use is subcategorized in Table 808-7 to the extent possible based on available meter
data and is depicted in Figure 808-7. “Other Municipal” includes facilities such as schools, and
various commercial, government, medical and nonprofit entities which have mixed water use and
cannot be specifically allocated to the other categories.
Table 808-7: DWS Existing Water Use by Categories – Kilauea Aquifer Sector Area
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 0.43 71.6
Industrial 0.00 0.4
Irrigation 0.00 0.0
Agriculture 0.00 0.0
Military 0.00 0.0
Other Municipal 0.17 28.1
Total 0.61 100.0
808 Kilauea Aquifer Sector Area
Page 808-18
Hawaii County
Water Use and Development Plan Update
Figure 808-7: DWS Existing Water Use by Categories – Kilauea Aquifer Sector Area
Domestic 71.6%Industrial 0.4%
Irrigation 0.0%
Agriculture 0.0%
Military 0.0%
Other Municipal
28.1%
808.3.7.2 State Water Systems
There are no State water systems in the Kilauea ASEA regulated by the DOH.
808.3.7.3 Federal Water Systems
There are two federal water systems in the Kilauea ASEA regulated by the DOH.
The Kilauea Military Camp water system described in Section 808.3.6 is operated by the U.S.
Military Joint Forces.
The Hawaii Volcanoes National Park water system is operated by the Department of the Interior.
DOH records indicate that a catchment supplies water to the system, which serves several
buildings, including the Kilauea Visitor Center, the restrooms at Thurston Lava Tube, Volcano
House restaurant and hotel, USGS Volcano Observatory, Namakani Paio Compound, park
offices and workshops, and park staff residences. The average demand is 0.027 mgd.
808.3.7.4 Private Public Water Systems
There are two private public water systems in the Kilauea ASEA regulated by the DOH.
808 Kilauea Aquifer Sector Area
Page 808-19
Hawaii County
Water Use and Development Plan Update
The Hawaiian Beaches Water System includes a 100,000 gallon steel tank serving approximately
3,388 people through 1,059 service connections to residential lots. The average pumpage from
one well is 0.82 mgd. The Hawaiian Shores subdivision is comprised primarily of residential
lots, with lots dedicated to parks, recreation center and water yard. The water system includes
one well and storage tank serving approximately 400 service connections. The average pumpage
from one well is 0.13 mgd. The two systems are connected by a valve that may be opened in an
emergency situation.
808.3.8 Water Use by Resource
808.3.8.1 Ground Water
Table 808-8 summarizes the current production, potential production (16 and 24-hour
operation), sustainable yield (SY), and percentage of SY for the various productions calculated.
Current production is represented by the highest 12-month moving average (MAV) or the
highest annual average yield calculated from the actual pumpage data. Potential well production
is based on installed pump capacities, and calculated for both 16 hours of operation a day and 24
hours of operation a day. Data is based on pumpage data reported to CWRM.
Table 808-8: Sustainable Yield – Kilauea Aquifer Sector Area
Sys Code System Area
High
12-Month
MAV (MGD)
Potential
16 -Hour
Production (MGD)
Potential
24-Hour
Production (MGD) SY (MGD)
High
12-Month
MAV
SY (%)
Potential
16-Hour
Production
SY (%)
Potential
24-Hour
Production
SY (%)
1.53 5.53 8.29 618 0.25 0.89 1.34
80801 Pahoa 1.47 3.53 5.30 435 0.34 0.81 1.22
80802 Kalapana 0.06 1.99 2.99 157 0.04 1.27 1.90
80803 Hilina 0.00 0.00 0.00 9 0.00 0.00 0.00
80804 Keaiwa 0.00 0.00 0.00 17 0.00 0.00 0.00
808.3.8.2 Surface Water
There are no known surface water uses in the sector area.
808.3.8.3 Rainwater Catchment
Water consumption calculated for developed parcels that are not supplied by groundwater or
surface water is assumed to be supplied by rainwater catchment. The water use previously
categorized as Domestic Use in Table 808-7 is assumed to be supplied by individual catchment
systems.
808 Kilauea Aquifer Sector Area
Page 808-20
Hawaii County
Water Use and Development Plan Update
808.3.8.4 Reclaimed Wastewater
There are no wastewater reclamation facilities within the Kilauea ASEA.
808.4 FUTURE WATER NEEDS
808.4.1 General
Table 808-9 summarizes the LUPAG, Zoning and 5-year incremental water demand projection
scenarios for the total aquifer sector area and the individual aquifer system areas. The
sustainable yield (SY) is presented to draw comparisons.
Table 808-9: Summary of Demand Projections
Growth Rate B Demand Projections (mgd)Without
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total Kilauea ASEA 618 36.5 4.6 4.4 5.1 6.0 7.0 8.2
80801 – Pahoa ASYA 435 33.3 3.8 3.8 4.4 5.2 6.1 7.1
80802 – Kalapana ASYA 157 3.1 0.8 0.6 0.7 0.8 0.9 1.1
80803 – Hilina ASYA 9 0.0 0.0 0.0 0.0 0.0 0.0 0.0
80804 – Keaiwa ASYA 17 0.1 0.0 0.0 0.0 0.0 0.0 0.0
Growth Rate B Demand Projections (mgd)With
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total Kilauea ASEA 618 127.3 94.5 6.6 7.7 9.0 10.4 12.2
80801 – Pahoa ASYA 435 67.6 37.6 4.6 5.4 6.3 7.4 8.6
80802 – Kalapana ASYA 157 53.1 50.4 1.8 2.1 2.5 2.9 3.4
80803 – Hilina ASYA 9 0.0 0.0 0.0 0.0 0.0 0.0 0.0
80804 – Keaiwa ASYA 17 6.6 6.5 0.2 0.2 0.2 0.2 0.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
For all aquifer system areas, full build-out and 2025 projection water demands excluding
agricultural demands are a small fraction the SY. Therefore, analysis of the three demand
scenarios does not need to be broken down by aquifer system areas and thus will be presented for
the aquifer sector area only.
808.4.2 Full Build-Out Water Demand Projections
The full build-out water demand projections based on the General Plan and County Zoning for
the Kilauea ASEA are listed in Tables 808-10 and 808-11, and reflect refinement as discussed
below. Each land use class is associated with the most appropriate CWRM water use category.
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Table 808-10: Hawaii County General Plan Full Build-Out Water Demand Projection –
Kilauea Aquifer Sector Area
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 20.7
Urban Expansion Domestic/Irrigation/Municipal 3.3
Resort Irrigation/Municipal 0.2
Industrial Industrial 0.2
Agriculture Agriculture 90.8
University Irrigation/Municipal 0
Rural Irrigation/Municipal 10.9
DHHL Irrigation/Municipal 1.4
TOTAL w/o Ag* 36.5
TOTAL w/ Ag* 127.3
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Table 808-11: County Zoning Full Build-Out Water Demand Projection – Kilauea Aquifer
Sector Area
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 3.1
Resort Irrigation/Municipal 0.0
Commercial Municipal 0.1
Industrial Industrial 0.0
Agriculture Agriculture 89.9
DHHL Irrigation/Municipal 1.4
TOTAL w/o Ag* 4.6
TOTAL w/ Ag* 94.5
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
808.4.2.1 Refine Land Use Based Projection
808.4.2.1.1 State Water Projects Plan
The total projected demand to the year 2020 for 23 State Water Projects within the Kilauea
ASEA is 1.71 mgd, using 0.23 mgd potable, 1.47 mgd nonpotable, and 0.01 nonpotable using
potable sources. These demands account for up to 25 percent of the projected total demand for
the sector area. The projects that will generate the most significant demands, with the exception
of DHHL projects, which are covered separately, are listed in Table 808-12.
808 Kilauea Aquifer Sector Area
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Water Use and Development Plan Update
Table 808-12: Future State Water Projects to Generate Significant Demands
Project Name
Primary Use
State
Department
2020 Demand
(mgd)
Hawaiian Paradise Park Elementary
School Potable DOE 0.06
Keeau High School 2nd Increment Potable DOE 0.048
808.4.2.1.2 State Department of Hawaiian Home Lands
The Makuu Tract consists of two pre-1994 sections with a total area of 2,000 acres; including
Makuu 1 north of Pahoa Village below the highway, and Makuu-2 above the highway, and the
Makai section along the coast south of Hawaiian Paradise Park Subdivison. DHHL has proposed
demands only for the mauka sections. The total average demand for the existing farm lots, and
the proposed agricultural, residential and commercial lots is 1.38 mgd. Water would be supplied
by the DWS Pahoa Water System, which pumped 0.55 mgd of its 4 wells’ 1.91 mgd pump
capacity in 2005.
Keonepoko is a small tract a short distance south of Makuu-1. No demands have been proposed
by DHHL.
808.4.2.1.3 Agricultural Water Use and Development Plan
There is no information available in the AWUDP specific to activity within the Kilauea ASEA to
further refine projections.
808.4.3 Water Use Unit Rates
Water use unit rates are based on the Water System Standards as discussed in Chapter 1.
808.4.4 5-Year Incremental Water Demand Projection to the Year 2025
The following section presents 5-year incremental water demand projections to the year 2025 for
the Kilauea ASEA. The projected low, medium, and high growth rates are listed in Table 808-
13, and are graphed in Figure 808-8. Potable and nonpotable water demands are also
differentiated.
Figure 808-9 illustrates the magnitude of the sustainable yield, both LUPAG and Zoning full
build-out water use, and water use projection through the year 2025 focusing on Medium Growth
Rate B. Figure 808-10 shows the breakdown of water demand projections by CWRM categories
through the year 2025. Table 808-14 summarizes these figures.
808 Kilauea Aquifer Sector Area
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Water Use and Development Plan Update
Table 808-13: Water Demand Projection – Kilauea Aquifer Sector Area
Without Agricultural Demands* (mgd) With Agricultural Demands* (mgd)
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 4.4 5.1 5.9 6.9 8.0 6.6 7.6 8.9 10.3 11.9
Potable 4.4 5.1 5.9 6.9 8.0 4.4 5.1 5.9 6.9 8.0
Nonpotable 0.0 0.0 0.0 0.0 0.0 2.2 2.6 2.9 3.4 3.9
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 4.4 5.1 6.0 7.0 8.2 6.6 7.7 9.0 10.4 12.2
Potable 4.4 5.1 6.0 7.0 8.2 4.4 5.1 6.0 7.0 8.2
Nonpotable 0.0 0.0 0.0 0.0 0.0 2.2 2.6 3.0 3.4 4.0
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 4.4 5.2 6.2 7.3 8.6 6.6 7.8 9.3 10.9 12.9
Potable 4.4 5.2 6.2 7.3 8.6 4.4 5.2 6.2 7.3 8.6
Nonpotable 0.0 0.0 0.0 0.0 0.0 2.2 2.6 3.1 3.6 4.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 808-8: Water Demand Projection Summary – Kilauea Aquifer Sector Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
2005 2010 2015 2020 2025
YearDemand (mgd)Nonpotable w/o Ag*
Potable Total w/o Ag*
Nonpotable w/ Ag*
Potable
Total w/ Ag*
LEGEND: Growth Rate A Growth Rate B Growth Rate C
808 Kilauea Aquifer Sector Area
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Water Use and Development Plan Update
Table 808-14: Medium Growth Rate B Water Demand Projection by Category – Kilauea
Aquifer Sector Area
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 4.4 5.1 6.0 7.0 8.2
Total with Ag* 6.6 7.7 9.0 10.4 12.2
Domestic 2.7 3.1 3.7 4.3 5.0
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 0.0 0.0 0.0 0.0 0.0
Agriculture 2.2 2.6 3.0 3.4 4.0
Military 0.0 0.0 0.0 0.0 0.0
Municipal 1.7 2.0 2.3 2.7 3.1
Potable 4.4 5.1 6.0 7.0 8.2
Nonpotable w/o Ag* 0.0 0.0 0.0 0.0 0.0
Nonpotable w/ Ag* 2.2 2.6 3.0 3.4 4.0
DWS 0.7 0.8 1.0 1.1 1.3
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
808 Kilauea Aquifer Sector Area
Page 808-25
Hawaii County
Water Use and Development Plan Update
Figure 808-9: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Kilauea Aquifer Sector Area
0
100
200
300
400
500
600
700
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
LUPAG = 36–127
SY = 618
Zoning = 5–95
Legend*, **
808 Kilauea Aquifer Sector Area
Page 808-26
Hawaii County
Water Use and Development Plan Update
Figure 808-10: Medium Growth Rate B Water Demand Projection by Category –
Kilauea Aquifer Sector Area
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
808.4.5 DWS Historical Water Consumption Data Projections
DWS supplied water consumption was projected in 5-year increments to the year 2025 based on
DWS historical water system consumption data from 1970 to 2003, as shown on Figure 808-11.
Legend*, **
808 Kilauea Aquifer Sector Area
Page 808-27
Hawaii County
Water Use and Development Plan Update
Figure 808-11: DWS Water Demand Projection – Kilauea Aquifer Sector Area
Kilauea Aquifer Sector Water Systems
0.0
0.5
1.0
1.5
2.0
2.5
1970 1980 1990 2000 2010 2020mgdHistorical Projected
Year 2005: 1.40 mgd
Year 2010: 1.56 mgd
Year 2015: 1.71 mgd
Year 2020: 1.87 mgd
Year 2025: 2.02 mgd
This graph combines data for the Olaa-
Mt.View, Pahoa, and Kapoho-Kalapana
water systems.
Historical data provided by RW Beck, Inc.
Projections based on historical DWS water consumption data cannot be compared to projections
based on population growth rate, because most of the Olaa-Mt.View Water System is within the
Northeast Mauna Loa ASEA. However, the projected rate of growth of the future population is
considerably higher than the rate of increase based on historical consumption.
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
808.5 RESOURCE AND FACILITY RECOMMENDATIONS
808.5.1 Water Source Adequacy
808.5.1.1 Full Build-Out
Full development to the maximum density of the County General Plan and Zoning land use
within the Kilauea Aquifer Sector Area (ASEA)can be sustained by conventional water resources
if agricultural demands are not included. Water demands associated with the LUPAG scenario
amount to approximately 5 percent of the sustainable yield (SY) of the sector area, and the
existing zoning requires less than 1 percent of the SY. If worst case agricultural demands are
included, the LUPAG and Zoning full build-out water demand scenarios would require 21 and
15 percent of the SY, respectively.
808.5.1.2 Twenty-Year Projection
Existing and 20-year projected water demands are insignificant compared to the SY of the sector
area. Existing water demands are approximately 1 percent of the SY, and 2025 projected
demands range between 1 and 2 percent of the SY.
808.5.2 Source Development Requirements
808.5.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, are evaluated to meet projected water demands.
808.5.2.1.1 Conventional Water Resource Measures
808.5.2.1.1.1 Ground Water
Because of the continuing activity of Kilauea, and the youth of the geology, the groundwater
relationships are complex. Basal water exists along the coast of the Kalapana Aquifer System
Area (ASYA) and extends several miles inland. This is evidenced by the development of
existing potable water wells. Geothermal fluids also exist, and interestingly, are being developed
a few miles from existing potable water wells. Large volumes of high-level water exist in the rift
zone of Kilauea, but is likely accessible only in the Pahoa ASYA. Exploratory wells in the
Glenwood area of the adjacent Southeast Mauna Loa ASEA (805) have tapped high level water
at over 1,000 feet, however, high level potable water wells have yet to be put in service. Based
on chloride content of existing wells, development of basal groundwater sources should continue
at least a few miles inland of the coast. Undoubtedly, based on the measured head in the existing
wells, a large volume of basal water exists.
As indicated in the 1999 Central Puna Water Master Plan, it may be more economical to
develop high level water instead of basal water. In systems serving multiple pressure zones, high
808 Kilauea Aquifer Sector Area
Page 808-29
Hawaii County
Water Use and Development Plan Update
level water would be pumped at a higher elevation and thus may be transmitted downhill by
gravity and a series of pressure reducing valves, whereas basal water would require initial
pumping and a series of booster pumps.
808.5.2.1.1.2 Surface Water
Surface water is nearly non-existent in the Kilauea ASEA; there are no perennial streams and
only one registered stream diversion. Surface water sources are not considered a viable water
resource.
808.5.2.1.1.3 Water Transfer
Some degree of water transfer is already taking place. The service area of the DWS Olaa-Mt.
View Water System, sources for which are in the Northeast Mauna Loa ASEA (804), extends
into the Kilauea ASEA. The water transfer is not a concern as the DWS demands in the water
system are insignificant compared to the large sustainable yield of both aquifer sector areas.
Potable sources may be developed in either sector area and transferred to the other sector areas
without impacting the aquifer.
808.5.2.1.2 Alternative Water Resource Enhancement Measures
808.5.2.1.2.1 Rainwater Catchment Systems
The Kilauea ASEA is unique in that most of the residents within the sector area rely on rainwater
catchment systems as their sole potable water source. Most significantly, units within the 89-
square foot area in Central Puna comprised of 12 subdivisions, with the exception of the
immediate vicinity of Keeau-Pahoa Road, all utilize individual catchment systems. Except for
the uninhabited Hilina and Keaiwa ASYAs, the sector area receives sufficient ambient rainfall to
support catchment systems.
Larger scale rainwater catchment systems are also an option to supply nonpotable needs if
necessary. Many agricultural crops and irrigation needs can be satisfied by the ambient rainfall.
808.5.2.1.2.2 Wastewater Reclamation
Wastewater reclamation facilities are not considered a viable option at this time due to the small
service population of the municipal wastewater systems in the sector area. However, the
potential population of the Central Puna area, with an estimated 30,000 lots, could justify a
wastewater reclamation facility. Additionally, availability of reclaimed wastewater could help
supplement the significant contingent of 1-acre lots in the area that engage in live-grow
operations.
808.5.2.1.2.3 Desalination
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
The potential for desalination plants exist where brackish water is present from the coastline to a
few miles inland. In general, these areas typically are not served by a municipal water system,
have small service populations, and significant growth is not anticipated. In these areas, it is
probably more cost-effective to extend the municipal water system rather than construct
desalination facilities.
808.5.2.2 Demand-Side Management
808.5.2.2.1 Development Density Control
Full build-out demands associated with LUPAG maximum density are nearly eight times greater
than that of Zoning. The discrepancy results from vast areas classified as Rural in the LUPAG,
compared to Agricultural in Zoning. Many of these lots will likely be used for family
agricultural operations or residential dwellings. Additional sources eventually will be required;
however, these demands are sustainable by conventional resources. Development density of the
Rural designation was assumed to be 1 unit per acre, which is considerably lower than the island
average Urban and Residential land use unit density rates; therefore, development density control
is not considered necessary.
808.5.2.2.2 Water Conservation
The average water consumption per connection to the DWS water system in the Kilauea ASEA
is 550 gpd, which is higher than the island average, but the average consumption of DWS
accounts classified as “Residential” is less than 400 gpd per connection. The average potable
water consumption per capita from all sources is 150 gpd, which is acceptable.
The DWS Pahoa and Kalapana Water Systems have a significant percentage of water not
accounted for, with the Kalapana Water System having between 30 and 50 percent of the water
produced unaccounted. Although source production is still adequate to meet the projected
demands, and the amount of water lost is insignificant compared to the SY of the sector area, it
would be prudent for DWS to examine the economic impact of the water losses.
Demand and supply side conservation measures should continue to be stressed, but strict
enforcement is not critical at this point.
808.5.3 Recommended Alternatives
Consistent with the utility goals for the Puna District stated in the General Plan, alternative
means to finance the extension of water systems to subdivision that rely on catchment should be
considered. A feasibility study to investigate both the need and desire for a municipal water
system, either by extension of the existing system, or new system altogether, would be prudent.
The key consideration is that a municipal system should not be imposed on residents if it is not
desired.
808 Kilauea Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Groundwater sources in Olaa also should be investigated. A cost-benefit analysis would
determine whether to seek high level or basal potable water sources. Currently, DWS has
planned a new production well in the center of Mountain View. An observation well in the
vicinity indicates that high-level water over 1,000 feet in elevation should be expected.
809 Hualalai Aquifer Sector Area
Page 809-1
Hawaii County
Water Use and Development Plan Update
809 HUALALAI AQUIFER SECTOR AREA
809.1 SECTOR AREA PROFILE
809.1.1 General
The Hualalai Aquifer Sector Area (ASEA) includes the entire Hualalai shield volcano and is
surrounded by Mauna Loa. The sector area is divided into the Keahou [80901] and Kiholo
[80902] Aquifer System Areas (ASYA) along Hualalai’s main northwest-southeast rift zone.
Average rainfall in the Keahou ASYA ranges from less than 20 inches along the northwest coast
to about 125 inches in the Kahaluu Forest Reserve, resulting in a sustainable yield of 38 mgd.
Average rainfall in the Kiholo ASYA varies from less than 10 inches at the coast to 45 inches at
mid-elevation, making this system area one of the driest on the island, with a sustainable yield of
18 mgd. The total sustainable yield for the Hualalai ASEA is 56 mgd.
809.1.2 Economy and Population
809.1.2.1 Economy
North Kona continues to be a major visitor industry area with direct national and international
flights to the recently expanded Kona International Airport at Keahole, and contains over 45
percent of the total number of hotel rooms on the island.
Part of the Kona coffee belt lies within the Hualalai ASEA. The “coffee belt” has the ideal
climate without the need for irrigation for this crop. The demand and value of Kona coffee
continues to grow and has steadily increased to over $16 million in 1997.
North Kona supports many other industries, including timber, fishing, and quarrying,
manufacturing, service, wholesale and retail activities. According to the County General Plan,
Kona is considered the center for government, commercial and industrial activities for West
Hawaii. Additionally, Kona is also home to “big-box” retailers such as Costco, K-Mart, and
WalMart and international sporting events such as the IronMan Triathlon, the Hawaiian
International Billfish Tournament, and the Senior PGA Tournament of Champions at the
Hualalai Resort.
The Natural Energy Laboratory of Hawaii Authority (NELHA) is an ocean science and
technology park located at Keahole Point. In 2003, the facility hosted 34 projects, employed 206
employees, and together with its tenants, provides a total economic impact of approximately $40
million a year.
809.1.2.2 Population
Most of the North Kona district population lies within the Hualalai ASEA. The population
growth rate in the area has decreased since the rapid growth of the 70’s and 80’s.
809 Hualalai Aquifer Sector Area
Page 809-2
Hawaii County
Water Use and Development Plan Update
Table 809-1: Historical Population
1980 1990 2000
1980-90
% Change
1990-2000
% Change
13,565 21,987 28,163 62.1 28.1
Data source: 2000 U.S. Census
Data redistributed and evaluated for the Hualalai Aquifer Sector Area.
The population projection for the sector area in five-year increments for low, medium and high
growth cases show slower growth than in the past. According to the County General Plan,
growth in North Kona will be closely associated with the growth of the visitor and agricultural
industries.
Table 809-2: Population Projection
Growth
Rate 2000 2005 2010 2015 2020
2000-10
% Change
2010-20
% Change
A – Low 28,163 29,966 33,277 36,874 40,895 18.2 22.9
B – Medium 28,163 30,061 33,571 37,417 41,712 19.2 24.2
C – High 28,163 31,315 35,676 40,356 45,468 26.7 27.4
Data source: County General Plan, February 2005
Data redistributed and evaluated for the Hualalai Aquifer Sector Area.
809.1.3 Land Use
809.1.3.1 Hawaii County General Plan
The Hawaii County General Plan Land Use Pattern Allocation Guide (LUPAG) map for the
Hualalai ASEA is shown on Figure 809-1. The estimated land use allocation acreage for each
LUPAG designation within the sector area is listed in Table 809-3.
809 Hualalai Aquifer Sector Area
Page 809-5
Hawaii County
Water Use and Development Plan Update
Table 809-3: LUPAG Map Estimated Land Use Allocation Acreage – Hualalai Aquifer
Sector Area
LAND USE PATTERN ACREAGE % of TOTAL
High Density Urban 459 0.23
Medium Density Urban 1,493 0.75
Low Density Urban 6,167 3.09
Industrial 3,895 1.95
Important Agricultural Land 22,017 11.04
Extensive Agriculture 59,595 29.87
Orchard 379 0.19
Rural 995 0.50
Resort/Resort Node 2,482 1.24
Open 6,123 3.07
Conservation 83,676 41.94
Urban Expansion 11,770 5.90
University Use 462 0.23
TOTAL 199,512 100.00
The water utility courses of action for North Kona, as put forth in the Hawaii County General
Plan, are as follows:
(a) Continue to pursue groundwater source investigation, exploration and development in
areas that would provide for anticipated growth and an efficient and economic system
operation.
(b) Continue to evaluate growth conditions to coordinate improvements as required to the
existing water system in accordance with the North Kona Water System Master Plan.
(c) Explore and develop a well in Waiaha.
809.1.3.2 Hawaii County Zoning
Hawaii County Zoning for the Hualalai ASEA is shown on Figure 809-2. The estimated land
use allocation acreage for each zoning class within the sector area is listed in Table 809-4.
809 Hualalai Aquifer Sector Area
Page 809-6
Hawaii County
Water Use and Development Plan Update
Table 809-4: County Zoning Estimated Class Allocation Acreage – Hualalai Aquifer
Sector Area
ZONING CLASS ACREAGE
% of
TOTAL
Single Family Residential 2,679 1.36
Multi-Family Residential
(including duplex) 1,115 0.57
Residential-Commercial Mixed Use 24 0.01
Resort 639 0.32
Commercial 691 0.35
Industrial 2,509 1.27
Industrial-Commercial Mixed 205 0.10
Family Agriculture 230 0.12
Residential Agriculture 468 0.24
Agriculture 110,152 55.96
Open 62,555 31.78
Project District 1,743 0.89
Forest Reserve 13,850 7.04
(road) 2,713 1.36
TOTAL 199,572 100.00
809.2 EXISTING WATER RESOURCES
809.2.1 Ground Water
The Hualalai ASEA has a sustainable yield of 56 mgd. According to the CWRM database and
additional update information, there are 65 production wells in the sector area, including 21
municipal, 18 irrigation, 1 industrial and 25 other wells. There are also 24 wells drilled, and
categorized as “unused.” Refer to Appendix B for the well database. Figure 809-3 shows the
well locations. The industrial well is owned by Hawaiian Electric Light Company, Inc. and
pumps brackish water for cooling, and the majority of the “other” wells are used for aquaculture
or resort water features.
High-level groundwater was encountered in the early 1990’s within the Keauhou ASYA, which
is reflected in the WRPP sustainable yield; however the extent to which it could be developed
was not known. Exploratory drilling at elevations above 1600 feet mean sea level (msl)
encountered water elevations ranging from 25+ feet msl to 460+feet msl. Notably, 10 of the
municipal wells and 14 of the irrigation wells were drilled between 1990 and 2002, as this new
resource was rapidly developed. Growth in the area and the associated increase in demand for
water supplies led to competition among large landowners/developers for the new sources of
water supply and well sites. The CWRM became concerned over proper planning, well
placement and associated problems of well interference; and with the help and partnership
Kiholo80902
Keauhou80901
Honokohau
Kailua Bay
Makako Bay
Kailua Kona
Mahaiula Bay
Kiholo Bay
Kaupulehu
Kukio
Makalawena
KapalaoaWeliweli
Waiulua Bay
Anaehoomalu Bay
Kealakekua Bay
Keawakaheka Bay
Keauhou
LEGEND:
County Zoning
INDEX MAP - Island of Hawaii
P A C I F I C O C E A N
2 0 21
Miles
Agricultural - 1 thru 10 acresAgricultural - 20 acresAgricultural - 35 acresAgricultural - 40 acresAgricultural - 80 acresAgricultural - 200 thru 255 acresAgricultural - 500 acresAgricultural - 600 acresAgricultural - 800 acresAgricultural - 900 acresAgricultural Project DistrictsDowntown Hilo Commercial DistrictCommercial, GeneralCommercial, NeighborhoodCommercial, VillageFamily AgriculturalForest ReserseIndustrial - CommercialIndustrial, GeneralIndustrial, LimitedOpenProject DistrictsResidentail and AgriculturalResidential - Commercial Mixed UseResidential Double-FamilyRes. Multi-Family - 7500-8000 sfRes. Multi-Family - 14,500-20,000 sfRes. Single Family - 7500-10,000 sfRes. Single Family - 15,000-20,000 sfHotel/Resort
Zoning Designations:
Aquifer SystemsKeauhou - 80901Kiholo - 80902
AQUIFER SECTORHUALALAI - 809
A-1a+A-20aA-35aA-40aA-80aA-200+A-500aA-600aA-800aA-900aAPDCDHCGCNCVFAFRMCXMGMLOPDRARCXRDRM-7.5+RM-14.5+RS-7.5+RS-15+V
Developed Parcels
FIGURE 809-2
Hawaiian Home Lands
FUKUNAGA & ASSOCIATES, INC.Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814Hawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-818
809 Hualalai Aquifer Sector Area
Page 809-9
Hawaii County
Water Use and Development Plan Update
Figure 809-3: Well Location
MAP CURRENTLY NOT AVAILABLE ON-LINE
809 Hualalai Aquifer Sector Area
Page 809-11
Hawaii County
Water Use and Development Plan Update
of the private sector, undertook the task to collect and analyze data, and continues to monitor
groundwater in West Hawaii.
809.2.2 Surface Water
Waiaha Stream is the only perennial stream in the area, due to the high permeability of the
basaltic lava flows from Mauna Loa and Hualalai volcanoes. In the wettest part of the rainbelt, a
few small springs may occur, such as Waiaha Springs; however, the small and intermittent
springs can sustain only small needs. There are 8 declared stream diversions in the CWRM
database listed in Table 809-5 and shown on Figure 809-4; however, flow data is not available.
Table 809-5: Stream Diversions – Hualalai Aquifer Sector Area
FILE REFERENCE TMK STREAM NAME
PALANI RANCH 7-4-001:003 Unnamed Stream diversion, Pipe #1 from tributary of Waiaha
Stream and rights claim.
GOMES J 7-5-014:002 Waiaha Stream diversion, pipe in concrete from Waiaha
Stream.
PALANI RANCH 7-6-001:002 Unnamed Stream diversion, Pipe #2 from tributary of Waiaha
stream and rights claim.
PALANI RANCH 7-6-001:002 Tributary to Waiaha Stream diversion, pipe from Waiaha Tributary and
rights claim (new entry).
TWIGG-SMITH C 7-7-005:002 Unnamed/ Unmapped Stream diversion, mauka dam on Unnamed stream
and rights claim. See new entries for 2 other dams.
TWIGG-SMITH C 7-7-005:002 Unnamed/ Unmapped Stream diversion, makai dam on Unnamed (new
entry).
TWIGG-SMITH C 7-7-005:002 Unnamed/ Unmapped Stream diversion, old Hawaiian dam on Unnamed
(new entry).
WALL RANCH 7-9-008:010 Unnamed/ Unmapped Stream diversion, pipe from Kawanui Stream.
809.2.3 Rainwater Catchment
The first potable water wells in the Hualalai ASEA were drilled in 1959 and were placed in
service in 1967. Prior to these sources, potable water was supplied primarily from individual
rainwater catchment systems. Rainwater catchment remains a viable resource for the area.
809.2.4 Reclaimed Wastewater
There are three wastewater reclamation facilities (WWRF) in the study area. Table 809-6 lists
the WWRF, reclaimed water classification, facility treatment capacity, current reuse amount, and
current application.
809 Hualalai Aquifer Sector Area
Page 809-12
Hawaii County
Water Use and Development Plan Update
Table 809-6: Wastewater Reclamation Facilities – Hualalai Aquifer Sector Area
Wastewater
Reclamation Facility
Reclaimed
Water
Classification
WWRF
Capacity
(MGD)
Current
Reuse
Amount
(MGD)
Irrigation Application
Heeia R-2 1.8 0.5
Kona and Alii Country Club Golf
Course
Kealakehe R-2 1.3 0.06 Swing Zone Driving Range
Kona International
Airport R-1 0.14 0.03 Landscape
809.3 EXISTING WATER USE
809.3.1 General
The following section presents the total estimated average water use within the Hualalai ASEA,
and the Keauhou and Kiholo ASYAs separately. Estimated water use from 2004 to 2005 was
estimated using DWS meter data and CWRM pumpage data from November 2004 through
October 2005, available GIS data, and estimated reclaimed wastewater usage, and are listed for
the sector and system areas in Tables 809-7, 809-7a, and 809-7b, respectively. Tables 809-7,
809-7a, and 809-7b and Figures 809-5, 809-5a, and 809-5b summarize water use in accordance
with CWRM categories. The tables and figures also indicate separately the quantities supplied
excluding agricultural demands, and the quantities supplied including worst case agricultural
demands (as described in Chapter 2) by the DWS system, non-DWS systems, and reclaimed
wastewater for the sector area and system areas, respectively.
809 Hualalai Aquifer Sector Area
Page 809-13
Hawaii County
Water Use and Development Plan Update
Figure 809-4: Streams & Diversions
MAP CURRENTLY NOT AVAILABLE ON-LINE
809 Hualalai Aquifer Sector Area
Page 809-15
Hawaii County
Water Use and Development Plan Update
Table 809-7: Existing Water Use by Categories – Hualalai Aquifer Sector Area
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.39 2.5 2.4
Industrial 0.07 0.4 0.4
Irrigation 3.02 19.3 18.5
Reclaimed WW 0.59 3.8 3.6
Agriculture 0.70 0.0 4.3
Military 0.00 0.0 0.0
Municipal
DWS System 9.45 60.5 57.9
Private Public WS 2.10 13.4 12.9
Total without Ag* 15.62 100.0
Total with Ag* 16.33 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 809-5: Existing Water Use by Categories – Hualalai Aquifer Sector Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Domestic 2.5%
Industrial 0.4%
Irrigation 19.3%
Irrigation (Recl'd
WW) 3.8%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 13.4%
Municipal
(DWS) 60.5%
Domestic 2.4%
Industrial 0.4%
Irrigation 18.5%
Irrigation (Recl'd
WW) 3.6%
Agriculture 4.3%
Military 0.0%
Municipal
(Non-DWS) 12.9%
Municipal
(DWS) 57.9%
w/o Agricultural Water Use* with Agricultural Water Use*
809 Hualalai Aquifer Sector Area
Page 809-16
Hawaii County
Water Use and Development Plan Update
Table 809-7a: Existing Water Use by Categories – Keauhou Aquifer System Area [80901]
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.35 3.1 3.0
Industrial 0.07 0.6 0.6
Irrigation 0.38 3.4 3.2
Reclaimed WW 0.59 5.2 4.9
Agriculture 0.71 0.0 5.9
Military 0.00 0.0 0.0
Municipal
DWS System 9.44 83.4 78.5
Private Public WS 0.48 4.2 4.0
Total without Ag* 11.31 100.0
Total with Ag* 12.02 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 809-5a: Existing Water Use by Categories – Keauhou Aquifer System Area
[80901]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Domestic 3.1%
Industrial 0.6%
Irrigation 3.4%
Irrigation (Recl'd
WW) 5.2%
Agriculture 0.0%
Military 0.0%
Municipal
(Non-DWS) 4.2%Municipal
(DWS) 83.4%
Domestic 3.0%
Industrial 0.6%
Irrigation 3.2%
Irrigation (Recl'd
WW) 4.9%
Agriculture 5.9%
Military 0.0%
Municipal
(Non-DWS) 4.0%
Municipal
(DWS) 78.5%
with Agricultural Water Use*w/o Agricultural Water Use*
809 Hualalai Aquifer Sector Area
Page 809-17
Hawaii County
Water Use and Development Plan Update
Table 809-7b: Existing Water Use by Categories – Kiholo Aquifer System Area [80902]
CWRM Water Use
Category
Water Use
(MGD)
Percent of Total
without Ag*
Percent of Total
with Ag*
Domestic 0.04 0.9 0.9
Industrial 0.00 0.0 0.0
Irrigation 2.64 61.2 61.2
Reclaimed WW 0.00 0.0 0.0
Agriculture 0.00 0.0 0.0
Military 0.00 0.0 0.0
Municipal
DWS System 0.01 0.2 0.2
Private Public WS 1.62 37.6 37.6
Total without Ag* 4.31 100.0
Total with Ag* 4.31 100.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 809-5b: Existing Water Use by Categories – Kiholo Aquifer System Area [80902]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 809-6 shows the approximate service area for the various water systems and indicates the
extent of the DWS water system.
809.3.2 Domestic Use
Domestic use or water use by individual households is minimal, and is assumed to be supplied
by private individual rainwater catchment systems.
Domestic 0.9%
Industrial 0.0%
Irrigation 61.2%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%Municipal
(Non-DWS) 37.6%
Municipal
(DWS) 0.2%
Domestic 0.9%
Industrial 0.0%
Irrigation 61.2%
Irrigation (Recl'd
WW) 0.0%
Agriculture 0.0%
Military 0.0%Municipal
(Non-DWS) 37.6%
Municipal
(DWS) 0.2%
with Agricultural Water Use w/o Agricultural Water Use
809 Hualalai Aquifer Sector Area
Page 809-18
Hawaii County
Water Use and Development Plan Update
809.3.3 Industrial Use
Industrial use is minimal. Hawaiian Electric Light Company, Ltd. has one well in the Keauhou
ASYA, which is used for cooling and combustion. Unlike at the HELCO Hilo plant, this water
is not injected back into the ground.
809.3.4 Irrigation Use
Irrigation makes up a significant portion of the water used in the Hualalai ASEA. Estimated
irrigation use is based on pumpage reported for private wells categorized by CWRM as irrigation
wells and reclaimed water use as indicated previously in Table 809-6. Table 809-8 lists the
average private irrigation well pumpage reported to CWRM.
Table 809-8: Private Irrigation Well Pumpage – Hualalai Aquifer Sector Area
Private Irrigation Irrigation Well Pumpage (mgd)
Big Island Country Club Not reported
Bishop Estate 0.09
Kona Country Club 0.15
Kona Village 0.10
Hualalai Resort 1.23
Kukio 1.01
Otaka Inc./Kaneyoshi 0.14
West Hawaii Landfill 0.30
TOTAL 3.02
809.3.5 Agricultural Use
Estimated agricultural water use within the Hualalai ASEA is relatively low considering the
amount of agricultural activity within the area. A portion of the Kona coffee belt is within the
Hualalai ASEA; however, coffee cultivation relies primarily on ambient or available rainfall for
production. Agricultural use in the amount of 1.2 mgd is supplied by DWS.
Aquaculture is a notable industry with the Natural Energy Laboratory of Hawaii Authority
(NELHA) located within the Hualalai ASEA. This facility primarily uses deep cold seawater.
Uwajima Fisheries, Inc. is a commercial tenant of NELHA, and grows coldwater flounder,
highly prized for Hawaii's sashimi and sushi markets; and also conducts semi-intensive
polyculture of moi (a type of Pacific threadfin fish), milkfish and ogo (seaweed). Uwajima
Fisheries owns 11 brackish water wells; however, pumpage data is not available. Cyanotech
Corporation also is a commercial tenant of NELHA, and uses cold seawater in their patented
Ocean Chill Drying process to grow microalgae. Cyanotech Corporation owns 2 wells used for
net washing and dust control. Pumpage data also is not available.
LEGEND:
FUKUNAGA & ASSOCIATES, INC.
Consulting Engineers1388 Kapiolani Boulevard, Honolulu, Hawaii 96814
Water SystemandService Area
INDEX MAP - Island of Hawaii
2 0 21
Miles
Aquifer SystemsKiholo - 80901Keauhou - 80902
AQUIFER SECTOR
HUALALAI - 809
Private Water System Service Area
Possible Catchment Area(Building Value > $10000)
DWS Water System Service Area
Aquifer Boundary
DWS Water SystemHawaii CountyDepartment of Water SupplyDWS UPDATE TO THE WATER USEAND DEVELOPMENT PLANJob No. 2003-818North Kona
Waikoloa
Kukio Utility Company
Keauhou80901
Kiholo80902
Puuwaawaa Water Works
Kaupulehu
FIGURE 809-6
809 Hualalai Aquifer Sector Area
Page 809-21
Hawaii County
Water Use and Development Plan Update
Military Use
There is no military use in the Hualalai ASEA.
809.3.6 Municipal Use
Municipal use is subcategorized into the other water use categories, namely Domestic, Industrial,
Irrigation, Agriculture, and Military, if detailed information is available.
809.3.6.1 County Water Systems
The County Department of Water Supply has one system in North Kona. It is the second largest
system on the island. The average water sale from November 2004 through October 2005 was
previously listed in Table 809-7. The system is supplied by ground water sources, including 10
wells and the Kahaluu inclined shaft.
The Kona Water System extends from the Kona International Airport south to the South Kona
boundary where interconnection with the South Kona Water System is made. The Kona districts
were without any County water systems until funds were provided by the Legislature in 1951.
The first increment of the North Kona Water System was completed in 1953. Surface water
from Waiaha Stream was diverted into large storage tanks located in Waiaha above Mamalahoa
Highway, filtered, then piped down to Kailua by a small transmission line to large tanks above
Kailua Village. This provided the impetus for the resort development which occurred in
subsequent years. The first potable water wells were placed in service in 1967. Expansion of the
system, mainly through legislative funds, continued for years. Most of the small pipelines
initially installed have been replaced with larger mains. The system expanded to Keauhou,
permitting the development of hotels along this coastline. Expansion to Kona International
Airport opened up a new area for development, such as the Honokohau Small Boat Harbor. The
expansion program did not neglect the existing farming community in the mauka areas, as the
system eventually was extended to service the North Kona District from Kalaoa Homesteads to
the South Kona boundary, a distance of over 18 miles.
DWS water use is subcategorized in Table 809-9 to the extent possible based on available meter
data. There is no DWS water system in the Kiholo ASYA. This use is depicted in Figure 809-7.
“Other Municipal” subcategory includes facilities such as schools, and various commercial,
government, medical and nonprofit entities which have mixed water use and cannot be
specifically allocated to the other categories.
809 Hualalai Aquifer Sector Area
Page 809-22
Hawaii County
Water Use and Development Plan Update
Table 809-9: DWS Existing Water Use by Categories – Hualalai Aquifer Sector Area
CWRM Water Use
Category
DWS Purveyed
Water Use
(MGD) Percent of Total
Domestic 5.20 55.0
Industrial 0.00 0.0
Irrigation 0.06 0.6
Agriculture 1.20 12.7
Military 0.00 0.0
Other Municipal 2.99 31.6
Total 9.45 100.0
Figure 809-7: DWS Existing Water Use by Categories – Hualalai Aquifer Sector Area
Industrial 0%
Military 0%
Domestic 55.0%
Irrigation 0.6%
Agriculture 12.7%
Other Municipal
31.6%
809.3.6.2 State Water Systems
There are no State water systems in the Hualalai ASEA.
809.3.6.3 Federal Water Systems
There are no Federal water systems in the Hualalai ASEA.
809 Hualalai Aquifer Sector Area
Page 809-23
Hawaii County
Water Use and Development Plan Update
809.3.6.4 Private Public Water Systems
There are three private public water systems within the Hualalai ASEA regulated by the
Department of Health. These systems supply a significant percentage of the total estimated
water use within the sector area.Table 809-10 lists the average pumpage of each system
reported to the CWRM. This pumpage is assumed to be the system water use.
Table 809-10: Private Public Water System Water Use – Hualalai Aquifer Sector Area
Private Public Water System
Water Use
(mgd)
Napuu Water, Inc. 0.04
Hualalai Development Company 1.33
Kukio Utility Company 0.73
Napuu Water, Inc. (NWI) is a member owned non-profit cooperative responsible for providing
water to the rural communities of Puuwaawaa, Puuanahulu, and Puu Lani Ranch. The NWI
serves a combined community population of 330 people with 147 connections, including 132
residential connections, 3 cattle ranchers with 7 connections, 5 DLNR, Division of Forestry and
Wildlife connections including the 5 MG Puuwaawaa reservoir, the Big Island Country Club, the
HELCO Puuanahulu substation, and the Puuanahulu Volunteer Fire Station.
The Hualalai Development Company owns several wells that serve the Hualalai Resort and Kona
Village Resort. These include eight brackish wells categorized as “Other” which are assumed to
be used for resort water features; five wells for irrigation; and four wells currently dedicated as
potable water sources which are treated by a 1 MGD reverse osmosis water treatment plant.
Potable water needs for ultimate build-out is anticipated to require two additional wells, two
additional reservoirs and increased capacity of the reverse osmosis water treatment plant to 3
MGD. Pumpage from the “Other” wells is not reported, and irrigation pumpage is noted in the
previous section on Irrigation Use.
WB Kukio Resorts, LLC owns wells which are operated by Kukio Utility Company. These
include three brackish wells for irrigation, and two wells categorized as “Other” and used as
“Lagoon” wells. WB Kukio Resorts LLC also acquired the five Huehue Ranch wells drilled
from the late 80’s through the early 90’s and continues to serve the Huehue Ranch area. These
wells require corrosion control and disinfection (not desalination), and the water serving the
private oceanfront club and residential community is treated at a new 1.27 MGD reverse osmosis
water treatment plant, which will be expanded to 1.7 MGD in the next phase. Irrigation
pumpage is noted in the previous section on Irrigation Use.
809.3.7 Water Use by Resource
809.3.7.1 Ground Water
Table 809-11 summarizes the current production, potential production (16 and 24 hour
operation), sustainable yield (SY), and percentage of SY for the various productions calculated.
Addendum No. 1, 2/3/2012
809 Hualalai Aquifer Sector Area
Page 809-24
Hawaii County
Water Use and Development Plan Update
Current production is represented by the highest 12-month moving average (MAV) or the
highest annual average yield calculated from the actual pumpage data. Potential well production
is based on installed pump capacities, and calculated for both 16 hours of operation a day and 24
hours of operation a day. Data is based on pumpage data reported to CWRM.
Table 809-11: Sustainable Yield and Pumpage – Hualalai Aquifer Sector Area
Sys Code System Area
High
12-Month
MAV
(MGD)
Potential
16 -Hour
Production
(MGD)
Potential
24-Hour
Production
(MGD) SY (MGD)
High
12-Month
MAV
SY
(%)
Potential
16-Hour
Production
SY
(%)
Potential
24-Hour
Production
SY
(%)
15.55 32.79 49.18 56 27.77 58.55 87.82
80901 Keauhou 11.49 16.58 24.87 38 30.24 43.63 65.45
80902 Kiholo 4.06 16.21 24.31 18 22.56 90.04 135.06
809.3.7.2 Surface Water
There is no flow data available for surface water use within the Hualalai ASEA. Due to the
limited availability of surface water, use is assumed to be minimal.
809.3.7.3 Rainwater Catchment
Water consumption calculated for developed parcels that are not supplied by groundwater or
surface water is assumed to be supplied by rainwater catchment. The water use categorized as
Domestic Use in Table 809-7 is assumed to be supplied by individual catchment systems.
809.3.7.4 Reclaimed Wastewater
Three wastewater reclamation facilities within the Hualalai ASEA supply reclaimed wastewater
for irrigation use, as previously indicated in Table 809-7.
809.4 FUTURE WATER NEEDS
809.4.1 General
Table 809-12 summarizes the LUPAG, Zoning and 5-year incremental water demand projection
scenarios for the total aquifer sector area and the individual aquifer system areas. The
sustainable yield (SY) is presented to draw comparisons.
809 Hualalai Aquifer Sector Area
Page 809-25
Hawaii County
Water Use and Development Plan Update
Table 809-12: Summary of Demand Projections
Growth Rate B Demand Projections (mgd)Without
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total – Hualalai ASEA 56 206.9 42.3 15.6 17.5 19.5 21.7 24.2
80901 – Keauhou ASYA 38 170.8 39.1 11.3 12.6 14.1 15.7 17.5
80902 – Kiholo ASYA 18 36.1 3.2 4.3 4.8 5.4 6.0 6.7
Growth Rate B Demand Projections (mgd)With
Agricultural Demand*
SY
(mgd)
LUPAG
(mgd)
Zoning
(mgd)2005 2010 2015 2020 2025
Total – Hualalai ASEA 56 281.6 114.8 16.3 18.2 20.3 22.7 25.3
80901 – Keauhou ASYA 38 245.4 111.6 12.0 13.4 15.0 16.7 18.6
80902 – Kiholo ASYA 18 36.2 3.2 4.3 4.8 5.4 6.0 6.7
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
LUPAG water demands excluding agricultural demands for the Hualalai ASEA and both aquifer
system areas exceed the respective SY. Zoning water demands excluding agricultural demands
for the Keauhou ASYA exceed its SY; however, for the Kiholo ASYA are less than its SY.
Analysis of the three demand projection scenarios will be presented for the aquifer sector area
and for each of the aquifer system areas.
809.4.2 Full Build-Out Water Demand Projections
The full build-out water demand projections based on the General Plan and County Zoning for
the Hualalai ASEA are listed in Tables 809-13 and 809-14, and reflect refinement as discussed
below. Each land use class is associated with the most appropriate CWRM water use category.
Table 809-13: Hawaii County General Plan Full Build-Out Water Demand Projection –
Hualalai Aquifer Sector Area
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 73.1
Urban Expansion Domestic/Irrigation/Municipal 71.7
Resort Irrigation/Municipal 42.2
Industrial Industrial 15.6
Agriculture Agriculture 74.7
University Irrigation/Municipal 1.8
Rural Irrigation/Municipal 1.0
DHHL Irrigation/Municipal 1.5
TOTAL w/o Ag* 206.9
TOTAL w/ Ag* 281.6
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
809 Hualalai Aquifer Sector Area
Page 809-26
Hawaii County
Water Use and Development Plan Update
Table 809-14: County Zoning Full Build-Out Water Demand Projection – Hualalai Aquifer
Sector Area
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 18.0
Resort Irrigation/Municipal 8.9
Commercial Municipal 2.1
Industrial Industrial 12.0
Agriculture Agriculture 72.5
DHHL Irrigation/Municipal 1.5
TOTAL w/o Ag* 42.3
TOTAL w/ Ag* 114.8
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
The full build-out water demand projections based on the General Plan and County Zoning for
the Keauhou Aquifer System Area are listed in Tables 809-13a and 809-14a.
Table 809-13a: Hawaii County General Plan Full Build-Out Water Demand Projection –
Keauhou Aquifer System Area [80901]
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 71.5
Urban Expansion Domestic/Irrigation/Municipal 69.7
Resort Irrigation/Municipal 10.2
Industrial Industrial 15.6
Agriculture Agriculture 74.6
University Irrigation/Municipal 1.8
Rural Irrigation/Municipal 0.4
DHHL Irrigation/Municipal 1.5
TOTAL w/o Ag* 170.8
TOTAL w/ Ag* 245.4
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
809 Hualalai Aquifer Sector Area
Page 809-27
Hawaii County
Water Use and Development Plan Update
Table 809-14a: County Zoning Full Build-Out Water Demand Projection – Keauhou
Aquifer System Area [80901]
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 17.0
Resort Irrigation/Municipal 6.8
Commercial Municipal 2.0
Industrial Industrial 12.0
Agriculture Agriculture 72.5
DHHL Irrigation/Municipal 1.5
TOTAL w/o Ag* 39.1
TOTAL w/ Ag* 111.6
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
The full build-out water demand projections based on the General Plan and County Zoning for
the Kiholo Aquifer System Area are listed in Tables 809-13b and 809-14b.
Table 809-13b: Hawaii County General Plan Full Build-Out Water Demand Projection –
Kiholo Aquifer System Area [80902]
LUPAG Class CWRM Category
Water Demand
(mgd)
Urban Domestic/Irrigation/Municipal 1.6
Urban Expansion Domestic/Irrigation/Municipal 2.0
Resort Irrigation/Municipal 32.0
Industrial Industrial 0.0
Agriculture Agriculture 0.1
University Irrigation/Municipal 0.0
Rural Irrigation/Municipal 0.6
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 36.1
TOTAL w/ Ag* 36.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
809 Hualalai Aquifer Sector Area
Page 809-28
Hawaii County
Water Use and Development Plan Update
Table 809-14b: County Zoning Full Build-Out Water Demand Projection – Kiholo
Aquifer System Area [80902]
Zoning Class CWRM Category
Water Demand
(mgd)
Residential Domestic/Irrigation/Municipal 1.0
Resort Irrigation/Municipal 2.1
Commercial Municipal 0.1
Industrial Industrial 0.0
Agriculture Agriculture 0.0
DHHL Irrigation/Municipal 0.0
TOTAL w/o Ag* 3.2
TOTAL w/ Ag* 3.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
809.4.2.1 Refine Land Use Based Projection
809.4.2.1.1 State Water Projects Plan
The total projected demand to the year 2020 for 30 State Water Projects listed in the Hawaii
SWPP, 2003, within the Hualalai ASEA is 4.99 mgd of potable water. These demands may
account for over 20 percent of the water demands within the sector area. The projects which will
generate the most significant demands, with the exception of DHHL projects, which are covered
separately, are listed in Table 809-15. Projects with large demands greater than 1 mgd may
require State funding to develop resources and infrastructure necessary to provide water service.
Table 809-15: Future State Water Projects to Generate Significant Demands
Project Name
Primary Use
State
Department
2020 Demand
(mgd)
Natural Energy Laboratory of Hawaii Potable NELHA 1.80
Kona International Airport Master Plan Potable
Department of
Transportation 0.24
809.4.2.1.2 State Department of Hawaiian Home Lands
Three tracts within the Hualalai ASEA were transferred from the State Housing and Community
Development Corporation (HCDC) to DHHL in 1994. The Keahuolu and Honokohau tracts
include 350 acres of land anticipated for residential and commercial development. The
Kealakehe tract is a 55-acre portion of the Villages of Laiopua anticipated for 236 residential
units. In 2004, the DHHL obtained the remainder of the Villages of Laiopua from HCDC and
the State of Hawaii, Department of Land and Natural Resources (DLNR). The entire Villages of
Laiopua has an estimated potential of 2,000 residential units, which corresponds to an average
daily demand of 0.8 mgd. The total potable water requirement of all DHHL tracts based on the
809 Hualalai Aquifer Sector Area
Page 809-29
Hawaii County
Water Use and Development Plan Update
2002 DHHL Water Resources report, and refined with updated information from DHHL, is 1.46
mgd.
809.4.2.1.3 Agricultural Water Use and Development Plan
There is no information available in the AWUDP specific to activity within the Hualalai ASEA
to further refine projections.
809.4.3 Water Use Unit Rates
Water use unit rates are based on the Water System Standards as discussed in Chapter 2,
Technical Approach, and single family residential (Low Density Urban category of the General
Plan and RS or Single-Family Residential category of County Zoning) consumption is 400
gallons per unit and 2.5 units per lot based on historical consumption data for the area.
809.4.4 5-Year Incremental Water Demand Projections to the Year 2025
The following section presents 5-year incremental water demand projections to the year 2025 for
the Hualalai ASEA and the Keauhou and Kiholo ASYA separately. The projected low, medium,
and high growth rates are listed in Tables 809-16, 809-16a, and 809-16b for the sector and
system areas, respectively, and are graphed in Figures 809-8, 809-8a, and 809-8b. Potable and
nonpotable water demands are also differentiated.
Figures 809-9, 809-9a, and 809-9b illustrate the magnitude of the sustainable yield, both
LUPAG and Zoning full build-out water use, and water use projection through the year 2025
focusing on Medium Growth Rate B, for the sector and system areas, respectively. Figures 809-
10, 809-10a, and 809-10b show the breakdown of water demand projections by CWRM
categories through the year 2025. Tables 809-17, 809-17a, and 809-17b summarize these
figures for the sector and system areas, respectively.
809 Hualalai Aquifer Sector Area
Page 809-30
Hawaii County
Water Use and Development Plan Update
809.4.4.1 Hualalai Aquifer Sector Area
Table 809-16: Water Demand Projection – Hualalai Aquifer Sector Area
Without Agricultural Demands* With Agricultural Demands*
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 15.6 17.3 19.2 21.3 23.7 16.3 18.1 20.1 22.3 24.7
Potable 11.9 13.3 14.7 16.3 18.1 11.9 13.3 14.7 16.3 18.1
Nonpotable 3.7 4.1 4.5 5.0 5.6 4.4 4.9 5.4 6.0 6.6
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 15.6 17.5 19.5 21.7 24.2 16.3 18.2 20.3 22.7 25.3
Potable 11.9 13.3 14.9 16.6 18.5 11.9 13.3 14.9 16.6 18.5
Nonpotable 3.7 4.1 4.6 5.1 5.7 4.4 4.9 5.5 6.1 6.8
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 15.6 17.8 20.1 22.7 25.5 16.3 18.6 21.0 23.7 26.7
Potable 11.9 13.6 15.4 17.3 19.5 11.9 13.6 15.4 17.3 19.5
Nonpotable 3.7 4.2 4.7 5.3 6.0 4.4 5.0 5.7 6.4 7.2
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 809-8: Water Demand Projection Summary – Hualalai Aquifer Sector Area
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
5.0
10.0
15.0
20.0
25.0
30.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
5.0
10.0
15.0
20.0
25.0
30.0
2005 2010 2015 2020 2025
YearDemand (mgd)Total w/ Ag*
Potable
Nonpotable w/ Ag*
Total w/o Ag*
Potable
Nonpotable w/o Ag*
LEGEND: Growth Rate A Growth Rate B Growth Rate C
809 Hualalai Aquifer Sector Area
Page 809-31
Hawaii County
Water Use and Development Plan Update
Table 809-17: Medium Growth Rate B Water Demand Projection by Category – Hualalai
Aquifer Sector Area
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 15.6 17.5 19.5 21.7 24.2
Total with Ag* 16.3 18.2 20.3 22.7 25.3
Domestic 0.4 0.4 0.5 0.5 0.6
Industrial 0.1 0.1 0.1 0.1 0.1
Irrigation 3.6 4.0 4.5 5.0 5.6
Agriculture 0.7 0.8 0.9 1.0 1.1
Military 0.0 0.0 0.0 0.0 0.0
Municipal 11.5 12.9 14.4 16.0 17.9
Potable 11.9 13.3 14.9 16.6 18.5
Nonpotable w/o Ag* 3.7 4.1 4.6 5.1 5.7
Nonpotable w/ Ag* 4.4 4.9 5.5 6.1 6.8
DWS 9.4 10.6 11.8 13.1 14.6
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
809 Hualalai Aquifer Sector Area
Page 809-32
Hawaii County
Water Use and Development Plan Update
Figure 809-9: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Hualalai Aquifer Sector Area
0
50
100
150
200
250
300
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 56
LUPAG = 207–282
Zoning = 43–115
Legend*, **
809 Hualalai Aquifer Sector Area
Page 809-33
Hawaii County
Water Use and Development Plan Update
Figure 809-10: Medium Growth Rate B Water Demand Projection by Category –
Hualalai Aquifer Sector Area
0.0
5.0
10.0
15.0
20.0
25.0
30.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
Legend*, **
809 Hualalai Aquifer Sector Area
Page 809-34
Hawaii County
Water Use and Development Plan Update
809.4.4.2 Keauhou Aquifer System Area [80901]
Table 809-16a: Water Demand Projection – Keauhou Aquifer System Area [80901]
Without Agricultural Demands* With Agricultural Demands*
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 11.3 12.6 13.9 15.4 17.1 12.0 13.4 14.8 16.4 18.2
Potable 10.3 11.4 12.6 14.0 15.5 10.3 11.4 12.6 14.0 15.5
Nonpotable 1.0 1.2 1.3 1.4 1.6 1.7 1.9 2.2 2.4 2.6
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 11.3 12.6 14.1 15.7 17.5 12.0 13.4 15.0 16.7 18.6
Potable 10.3 11.5 12.8 14.3 15.9 10.3 11.5 12.8 14.3 15.9
Nonpotable 1.0 1.2 1.3 1.4 1.6 1.7 2.0 2.2 2.4 2.7
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 11.3 12.9 14.6 16.4 18.5 12.0 13.7 15.5 17.5 19.7
Potable 10.3 11.7 13.2 14.9 16.8 10.3 11.7 13.2 14.9 16.8
Nonpotable 1.0 1.2 1.3 1.5 1.7 1.7 2.0 2.3 2.5 2.9
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 809-8a: Water Demand Projection Summary – Keauhou Aquifer System Area
[80901]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
5.0
10.0
15.0
20.0
25.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
5.0
10.0
15.0
20.0
25.0
2005 2010 2015 2020 2025
YearDemand (mgd)Nonpotable w/ Ag*
Potable
Total w/ Ag*
Nonpotable w/o Ag*
Total w/o Ag*
Potable
LEGEND: Growth Rate A Growth Rate B Growth Rate C
809 Hualalai Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Table 809-17a: Medium Growth Rate B Water Demand Projection by Category –
Keauhou Aquifer System Area [80901]
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 11.3 12.6 14.1 15.7 17.5
Total with Ag* 12.0 13.4 15.0 16.7 18.6
Domestic 0.4 0.4 0.4 0.5 0.5
Industrial 0.1 0.1 0.1 0.1 0.1
Irrigation 1.0 1.1 1.2 1.3 1.5
Agriculture 0.7 0.8 0.9 1.0 1.1
Military 0.0 0.0 0.0 0.0 0.0
Municipal 9.9 11.1 12.3 13.8 15.3
Potable 10.3 11.5 12.8 14.3 15.9
Nonpotable w/o Ag* 1.0 1.2 1.3 1.4 1.6
Nonpotable w/ Ag* 1.7 2.0 2.2 2.4 2.7
DWS 9.4 10.5 11.7 13.1 14.6
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
809 Hualalai Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 809-9a: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Keauhou Aquifer System Area [80901]
0
50
100
150
200
250
300
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 38
LUPAG = 171–246
Zoning = 39–112
Legend*, **
809 Hualalai Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 809-10a: Medium Growth Rate B Water Demand Projection by Category –
Keauhou Aquifer System Area [80901]
0.0
5.0
10.0
15.0
20.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
Legend*, **
809 Hualalai Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
809.4.4.3 Kiholo Aquifer System Area [80902]
Table 809-16b: Water Demand Projection – Kiholo Aquifer System Area [80902]
Without Agricultural Demands* With Agricultural Demands*
GROWTH RATE A 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 4.3 4.8 5.3 5.9 6.5 4.3 4.8 5.3 5.9 6.5
Potable 1.7 1.9 2.1 2.3 2.5 1.7 1.9 2.1 2.3 2.5
Nonpotable 2.6 2.9 3.2 3.6 4.0 2.6 2.9 3.2 3.6 4.0
GROWTH RATE B 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 4.3 4.8 5.4 6.0 6.7 4.3 4.8 5.4 6.0 6.7
Potable 1.7 1.9 2.1 2.3 2.6 1.7 1.9 2.1 2.3 2.6
Nonpotable 2.6 3.0 3.3 3.7 4.1 2.6 3.0 3.3 3.7 4.1
GROWTH RATE C 2005 2010 2015 2020 2025 2005 2010 2015 2020 2025
Total 4.3 4.9 5.5 6.3 7.0 4.3 4.9 5.5 6.3 7.0
Potable 1.7 1.9 2.2 2.4 2.7 1.7 1.9 2.2 2.4 2.7
Nonpotable 2.6 3.0 3.4 3.8 4.3 2.6 3.0 3.4 3.8 4.3
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
Figure 809-8b: Water Demand Projection Summary – Kiholo Aquifer System Area
[80902]
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
2005 2010 2015 2020 2025
YearDemand (mgd)0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
2005 2010 2015 2020 2025
YearDemand (mgd)Total w/o Ag*
Nonpotable w/o Ag*
Potable
Total w/ Ag*
Nonpotable w/ Ag*
Potable
LEGEND: Growth Rate A Growth Rate B Growth Rate C
809 Hualalai Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Table 809-17b: Medium Growth Rate B Water Demand Projection by Category – Kiholo
Aquifer System Area [80902]
Water Use
Category
2005
(mgd)
2010
(mgd)
2015
(mgd)
2020
(mgd)
2025
(mgd)
Total without Ag* 4.3 4.8 5.4 6.0 6.7
Total with Ag* 4.3 4.8 5.4 6.0 6.7
Domestic 0.0 0.0 0.0 0.0 0.0
Industrial 0.0 0.0 0.0 0.0 0.0
Irrigation 2.6 3.0 3.3 3.7 4.1
Agriculture 0.0 0.0 0.0 0.0 0.0
Military 0.0 0.0 0.0 0.0 0.0
Municipal 1.7 1.8 2.1 2.3 2.6
Potable 1.7 1.9 2.1 2.3 2.6
Nonpotable w/o Ag* 2.6 3.0 3.3 3.7 4.1
Nonpotable w/ Ag* 2.6 3.0 3.3 3.7 4.1
DWS 0.0 0.0 0.0 0.0 0.0
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
809 Hualalai Aquifer Sector Area
Page 809-40
Hawaii County
Water Use and Development Plan Update
Figure 809-9b: Medium Growth Rate B Water Demand Projections and Full Build-Out –
Kiholo Aquifer System Area [80902]
0
5
10
15
20
25
30
35
40
2005 2010 2015 2020 2025
YearDemand (mgd)LUPAG w/o Ag
LUPAG w/ Ag
Zoning w/o Ag
Zoning w/ Ag
SY
B Total w/o Ag
B Total w/ Ag
B Potable
B N-P w/o Ag
B N-P w/ Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** The LUPAG and Zoning scenarios represent demand from full build-out to the maximum density allowed and are
not associated with a timeline. The B scenario represents the 5-year incremental demand based on Growth Rate B
population projections, with “Potable” representing the potable component, “N-P” representing the nonpotable
component and “Total” representing the sum of the two.
SY = 18
Zoning = 3
LUPAG = 36 Legend*, **
809 Hualalai Aquifer Sector Area
Page 809-41
Hawaii County
Water Use and Development Plan Update
Figure 809-10b: Medium Growth Rate B Water Demand Projection by Category – Kiholo
Aquifer System Area [80902]
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
2005 2010 2015 2020 2025
YearMGD Potable
N-P w/ Ag
N-P w/o Ag
Domestic
Industrial
Irrigation
Agriculture
Military
Municipal
Tot w/ Ag
Tot w/o Ag
* Demand scenarios without and with agricultural demands represent the potential minimum and maximum
agricultural demand, respectively, with the expectation that the actual demand will fall somewhere in between.
** ”N-P” represents the nonpotable component of the demand.
809.4.5 DWS Historical Water Consumption Data Projections
DWS supplied water consumption was projected in 5-year increments to the year 2025 based on
DWS historical water system consumption data from 1970 to 2003, as shown in Figure 809-11.
Legend*, **
809 Hualalai Aquifer Sector Area
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Hawaii County
Water Use and Development Plan Update
Figure 809-11: DWS Water Demand Projection – Hualalai Aquifer Sector Area
North Kona Water System
0
2
4
6
8
10
12
14
16
18
1970 1980 1990 2000 2010 2020mgdHistorical Projected
Year 2005: 10.3 mgd
Year 2010: 11.7 mgd
Year 2015: 13.1 mgd
Year 2020: 14.5 mgd
Year 2025: 15.8 mgd
Historical data and graph provided by RW Beck, Inc.
Projections based on historical DWS water consumption data are slightly higher than projections
based on population growth rate primarily because the projected demand for 2005 is higher than
actual data. The growth rate, however is consistent with the projections for the total sector area,
and indicates that DWS may need to supply potable water equivalent to over 50 percent of the
total projected water supply for the Hualalai ASEA.
809 Hualalai Aquifer Sector Area
Page 809-43
Hawaii County
Water Use and Development Plan Update
809.5 RESOURCE AND FACILITY RECOMMENDATIONS
809.5.1 Water Source Adequacy
809.5.1.1 Full Build-Out
The full development of the County General Plan land use maximum density within the Hualalai
Aquifer Sector Area (ASEA) cannot be sustained by conventional water resources, even if
agricultural demands are not included. The existing zoning would require over twice the existing
sustainable yield of the Hualalai ASEA if agricultural demands are included, and over 75 percent
of the SY if agricultural demands are not included. Demands from existing zoning for the
Keauhou Aquifer System Area (ASYA) would exceed its SY even if agricultural demands are
not included.
809.5.1.2 Twenty-Year Projection
Present water requirements are less than 30 percent of the Hualalai ASEA sustainable yield.
This is expected to increase to between 43 and 45 percent by 2025. The percentage of current
and projected water requirements of the sustainable yield within the Keauhou and Kiholo
ASYAs are similar.
809.5.2 Source Development Requirements
809.5.2.1 Supply-Side Management
Supply-side management, including conventional water resource measures and alternative water
resource enhancement measures, are evaluated to meet projected water demands.
809.5.2.1.1 Conventional Water Resource Measures
809.5.2.1.1.1 Ground Water
Until the implementation of the high-level Kalaoa Well in 1992, only basal well sources served
the DWS system. However, the permeability of the ground and the low hydraulic gradient of the
basal water table does not permit wells with high yields, which was evidenced with the rise in
chloride content of the Kahaluu Shaft. Small clusters of basal wells with smaller yields spread
out over a large area would be required.
Discovery of high-level ground water has triggered significant potable ground water resource
development in the Hualalai ASEA with seemingly promising potential. Most of the high-level
wells discovered within the Hualalai ASEA are located in the Keauhou ASYA. However, there
is also evidence of the occurrence of high-level ground water in the Kiholo ASYA. The 2003
report “A Study of the Ground-Water Conditions in North and South Kona and South Kohala
Districts” by the CWRM found that some of the high-level wells studied showed a slow decline
of water levels. The report also suggests that more than one geological mechanism may have
Addendum No. 1, 2/3/2012
809 Hualalai Aquifer Sector Area
Page 809-44
Hawaii County
Water Use and Development Plan Update
created the high-level aquifer, and that the flux of the aquifer flows in a north-south direction
with Keopu being the drain. Due to these uncertainties associated with the high-level aquifer,
development of this resource accompanied by advance studies would be prudent.
There are several potable water wells drilled which are unused, most of which are owned by
private entities. DWS has one well drilled, a second well planned, and is negotiating with
private developers for additional water resources which are already drilled. Because the high-
level aquifer lies within ground elevations above the 1,600 foot elevation, installation of new
wells would require drill depths in the 1,500-foot range, which would be substantially more
costly than wells in the basal aquifer. Energy costs would also be much greater due to the high
pumping head. The 1995 “North Kona Water Master Plan” by Fukunaga & Associates
suggested a water development shaft at Keopu-Puuhonua in lieu of a cluster of wells. A near
horizontal tunnel would head inland to a point above the high-level aquifer where shallow
vertical wells could be implemented. Limited well tests in the area suggest low drawdown and
rapid recovery of the aquifer.
Plans for future nonpotable water sources are not available. Current usage of existing brackish
wells primarily for irrigation purposes indicate brackish water is available in areas generally
makai of Mamalahoa Highway.
809.5.2.1.1.2 Surface Water
Surface water in the Hualalai ASEA is extremely limited. The spring sources in the vicinity of
Waiaha Stream may continue to provide localized needs but cannot be developed on a larger
scale. Surface water thus is not deemed a viable resource.
809.5.2.1.1.3 Water Transfer
Water requirements in the Keauhou ASYA will approach the system area’s sustainable yield
faster than in the Kiholo ASYA. The privately owned Huehue Ranch Water System has wells in
both system areas, therefore water transfer is already occurring between system areas. The DWS
North Kona Water System is contained entirely within the Keauhou ASYA. Development of
sources in the Kiholo ASYA would require extension of the existing water system.
Water transfer from the adjacent Southwest Mauna Loa ASEA (806) is an option to provide
water without increasing source production in the sector area. The 2025 potable water projection
for ASEA 806 is 2.6 mgd, and the potential 16-hour production of all potable water wells is 3.5
mgd, suggesting that up to 0.9 mgd may be transferred without stressing the existing sources in
ASEA 806. Because the sustainable yields of the ASEA 806 and more specifically the
Kealakekua ASYA (80603) far exceed the projected demands, developing additional sources in
the adjacent ASYA 80603 and transferring water into the Hualalai ASEA is a viable option.
The DWS North Kona Water System is already connected to the South Kona Water System in
ASEA 806 by a valve. Minor infrastructure changes would be needed to allow regular water
transfer.
Addendum No. 1, 2/3/2012
809 Hualalai Aquifer Sector Area
Page 809-45
Hawaii County
Water Use and Development Plan Update
809.5.2.1.2 Alternative Water Resource Enhancement Measures
809.5.2.1.2.1 Rainwater Catchment Systems
Most of the area within the Hualalai ASEA does not receive enough rainfall to support individual
catchments, although these may be viable in the wetter areas of the rainbelt mauka of
Mamalahoa Highway, such as within the vicinity of the Kahaluu Forest Reserve. These areas are
mainly zoned for Agricultural uses and are remote from the municipal water system; therefore,
catchment may be an option for satisfying the domestic water needs of family agriculture users.
Because most of the urban areas within the sector area are within the service area of a municipal
system, use of catchments as a sole source is unlikely; however, utilizing catchment systems to
supplement a municipal system might be a feasible alternative.
809.5.2.1.2.2 Wastewater Reclamation
The existing wastewater reclamation facilities have the potential capacity to produce
approximately 2 mgd of reclaimed wastewater for additional approved nonpotable uses. Effluent
reuse is dependent upon viable users within close proximity to the wastewater reclamation
facilities; otherwise, this is not a cost-effective alternative. Accordingly, smaller satellite
facilities combining a wastewater treatment plant and reclamation facility could be implemented.
This would require a carefully coordinated planning effort by several stakeholders, including
community development groups, and County Planning, DWS, and Department of Environmental
Management staff. Key factors to consider would include service area, proposed land use, costs,
and public opinion. Such facilities would be more effective to implement in new communities
rather than retrofitting or replacing existing systems; therefore, incorporating the analysis of this
alternative at the planning level is desirable.
809.5.2.1.2.3 Desalination
Desalination is a costly, but viable resource enhancement measure. Generally, desalination
plants favor economies of scale, so a single larger plant would be more cost-effective than
several smaller satellite plants. Preferable locations would be at moderate ground elevations to
reduce drilling and pumping costs, and outside the influence of potable water wells. As most of
the potable wells are located in a band mauka of Mamalahoa Highway, the area between Queen
Kaahumanu Highway and Mamalahoa Highway might be a suitable location for brackish water
wells. To reduce transmission system pumping costs, the service area would need to be
restricted to lower elevations.
809.5.2.2 Demand-Side Management
809.5.2.2.1 Development Density Control
The full build-out water demand projections are extremely high in comparison with the aquifer
sector area sustainable yield. The General Plan and existing zoning should be assessed in light
of the fact that the water resources may not be able to sustain the ultimate and potential planned
809 Hualalai Aquifer Sector Area
Page 809-46
Hawaii County
Water Use and Development Plan Update
development. The full build-out demand is based on worst-case scenario development densities;
therefore, reduction of current planned development densities should be considered. Preliminary
proposals for the Kona Community Development Plan currently being prepared by Wilson
Okamoto Corp. indicate urban densities in the 6 to 8 development units per acre range, which
would lead to significantly less demand than the ultimate scenarios presented.
809.5.2.2.2 Water Conservation
According to metering records, the average usage of DWS accounts in the Hualalai ASEA is
over 1,000 gpd per connection, with average usage of over 600 gpd per connection for residential
users, and over 5,000 gpd per connection for non-residential users, both of which are
considerably higher than planning level standards. Potable water usage averaged per capita for
the aquifer sector area is approximately 350 gpd. Average consumption for purely domestic
purposes is generally around 100 gpd per capita; therefore, it can be assumed that a significant
quantity, potentially as much as 250 gpd per capita, is being used for irrigation purposes.
Consumption could be significantly reduced through end-user conservation. A number of
measures may be implemented to facilitate end-user conservation, including water restrictions
during drier periods, public education, and more efficient landscaping practices. Water
purveyors could more easily justify implementing conservation measures in the Hualalai ASEA
than most other ASEAs, because it is one of the driest and warmest areas on the island, and
considering the volume of water used.
The DWS North Kona Water System is one of the most efficient on the island, having 97% of its
source water production accounted for by metering records. The costs to implement practices to
account for non-revenue water would not justify the minimal savings in source water.
809.5.3 Recommended Alternatives
Continued groundwater development is recommended; however, exploitation of the aquifer
sustainable yield, especially of the high-level aquifer, should be closely monitored in both
Aquifer System Areas. The forthcoming update to the Water Resource Protection Plan may
provide further insight into the extent to which the high-level aquifer can be developed.
Groundwater development in the adjacent Kealakekua ASYA (80603) and subsequent transfer of
water is also recommended if sources in the Keauhou ASYA become stressed.
The Kaloko-Honokohau National Historic Park is a 1,200-acre site located makai of Queen
Kaahumanu Highway. The park encompasses extraordinary and unique cultural and natural
resources which include terrestrial ecosystems, coral reef ecosystems, and significant
archeological sites such as modified anchialine pools and significant Hawaiian fishponds. It has
been brought to the attention of the CWRM that groundwater quality and discharge are vital to
the sustainability of these resources, and concerns have been raised over the potential cumulative
effects that increased groundwater extraction may have on these resources. The WUDP proposes
additional monitoring and studies to comprehensively evaluate the impacts on the park’s
resources, and utilization of this information to coordinate responsible planning of resource
development.
Addendum No. 1, 2/3/2012
809 Hualalai Aquifer Sector Area
Page 809-47
Hawaii County
Water Use and Development Plan Update
The concept of using the highest quality water for the highest end use cannot be emphasized
enough. According to DWS metering records, 1.19 mgd was drawn by users classified as
agricultural, which could be satisfied by nonpotable sources. Other non-residential uses
comprise a large portion of the potable water consumed, some of which could also be supplied
by nonpotable water, such as irrigation for commercial developments. Further studies on the
feasibility of transferring nonpotable users to nonpotable sources, and the other aforementioned
alternative water resource enhancement measures would be prudent. The benefits and
drawbacks of each alternative, along with input from the various stakeholders, should be
considered to develop an optimal combination of resource enhancement measures.
Water conservation is the responsibility of the community but must be facilitated by the water
purveyors. It is recommended that the Department of Water Supply, being the largest provider
of potable water in the Hualalai Aquifer Sector Area, develop water conservation programs,
primarily aimed at demand-side measures in order to reduce the average consumption per user
closer to the island-wide average.
Addendum No. 1, 2/3/2012
SUMMARY OF CONCLUSIONS AND GENERAL RECOMMENDATIONS
Page 4-1
Hawaii County
Water Use and Development Plan Update
4 SUMMARY OF CONCLUSIONS AND GENERAL RECOMMENDATIONS
Specific recommendations were presented for each aquifer sector area in Chapter 3; however, the
Hawaii Water Use and Development Plan Update promotes several common key themes which
are applicable island-wide.
1) Reserve the Highest Quality of Water for the Most Valuable End Use
The highest quality water should be reserved for the most valuable end use, thus the “need” for
water is emphasized. Potable water is considered the highest quality water; and the sustenance
of life is considered the most valuable end use. Landscaping is viewed as a luxury, not a
necessity for life; hence, usage of potable water for landscaping is considered unessential and is
discouraged. Lower quality nonpotable water, such as reclaimed wastewater, brackish
groundwater and untreated surface water, should be utilized for landscaping and agriculture
where feasible, thereby reserving potable water for human consumption. Usage of nonpotable
water can be promoted by installing nonpotable systems in the proximity of concentrated
development. Proper community planning and development is necessary to ensure the success of
this process.
2) Promote Water Conservation
Water should not be considered a commodity to be bought and sold, but rather, a public trust and
a valuable resource, which is the right of all people to share responsibly. Potable water usage
above the County standard of 400 gpd per household is considered excessive, and is therefore
discouraged. Both end users and water purveyors should work together to conserve potable
water. End users can follow the demand-side conservation practices described in Chapter 2 to
reserve potable water only for the sustenance of life, and water purveyors can follow the supply-
side conservation measures described in Chapter 2. County Planning can to an extent limit
future development water usage in potential water-short areas through land use and zoning
policies and by requiring LEED certified construction.
3) Initiate More Monitoring and Studies
The data and analyses presented in the WUDP are based on groundwater hydrologic units;
therefore, the accuracy of these units is essential. Additional monitoring and studies are
recommended to determine the “safe” sustainable yields of groundwater. The aquifer system
area sustainable yields currently are being updated in the WRPP; subsequent updates to the
WUDP should reflect the updated sustainable yields. The Framework also requires data and
analyses to be based on surface water hydrologic units; therefore, additional information on
surface water hydrologic units is required for future updates of the WUDP. Permitted use of
stream diversions is “status quo” until instream flow standards have been determined.
Data and analysis presented within each aquifer sector area chapter is specific to the individual
aquifer sector area. However, as demonstrated by the water transfers, source availability and
Summary of Conclusions and General Recommendations
Page 4-2
Hawaii County
Water Use and Development Plan Update
water usage are not confined within each individual aquifer sector area, but rather, are
interrelated between neighboring aquifer sector areas. Particularly in West Hawaii, there are
areas that will eventually begin to see significant competition for water resources. As such, it is
expected that the magnitude and extent of water transfers will increase in the future. Figures 4-1
and 4-2 show the location of present and expected future water transfers, respectively. Because
of these interdependencies, it is strongly recommended that regional studies be initiated that
examine such issues in greater depth and on a broader scale.
The WUDP proposes to create overall resource management practices that, where possible, will
include obtaining water development easements and sites for well fields, water tanks, reservoirs,
and transmission lines, as well as identifying hydraulic service zones on State lands to facilitate
strategic transmission between hydrologic zones proximate to lands designated for growth.
Qualified utility development of these resources will facilitate a long-term management and
protection strategy to the benefit of the greater community. Such development, whether on
government or privately-owned lands, will preclude undue competition for the resources as they
become more limited. To promote aquifer integrity, future updates of the WUDP should
promote a policy of well-planned source development.
The Department of Water Supply, as the largest purveyor of potable water on the island, plays a
key role in the use and protection of water resources. The goals and policies of DWS are
described in detail in Appendix C.
Water development coordination and cooperation between public and private sectors are
emphasized to assist the success of future planning. Involvement of collaborative and advisory
groups has had a positive impact on water resources planning, and it is encouraged that these
groups continue to provide input and insight.
REFERENCES
Page R-1
Hawaii County
Water Use and Development Plan Update
REFERENCES
“20-Year Water Master Plan, County of Hawaii, Department of Water Supply,” prepared for
County of Hawaii, Department of Water Supply; by R.W. Beck, Inc., June 2006.
“2002 Census of Agriculture, Farm and Ranch Irrigation Survey (2003), Volume 3, Special
Studies, Part 1,” prepared by U.S. Department of Agriculture, National Agricultural Statistics
Service, November 2004.
“2002 Census of Agriculture, Hawaii State and County Data, Volume 1, Geographic Area
Series, Part 11,” prepared by U.S. Department of Agriculture, National Agricultural Statistics
Service, June 2004.
“A Study of the Ground-Water Conditions in North and South Kona and South Kohala Districts,
Island of Hawaii, 1991-2002,” prepared for State of Hawaii, Department of Land and Natural
Resources, Commission on Water Resource Management; by Glenn R. Bauer, September 2003.
“Agricultural Water Use and Development Plan,” prepared for State of Hawaii, Department of
Agriculture; by Water Resource Associates, Honolulu, HI, December 2003.
“Bulletin 9, Geology and Ground-Water Resources of the Island of Hawaii,” prepared for Hawaii
Division of Hydrography; by Harold T. Stearns and Gordon A. Macdonald, 1946.
“Central Puna Water Master Plan, Puna District, Island of Hawaii,” prepared for County of
Hawaii, Department of Water Supply; by Roy Takemoto in coordination with Hilo Engineering,
Inc., and Waimea Water Services, Inc., Hilo, HI, March 1999.
“County of Hawaii, General Plan 10-Year Review, Infrastructure Assessment Report,” prepared
for County of Hawaii, Planning Department; by Roy Takemoto in association with Raymond
Suefuji and Maptech, Inc., Hilo, HI, December 2000.
“Final Reconnaissance Report, Hawaii Water Management, Kau Irrigation System, Island of
Hawaii,” prepared by U.S. Army Corps of Engineers, Honolulu District, Fort Shafter, HI,
October 2000.
“Final Report, Kau to South Kona Water Master Plan,” prepared for County of Hawaii, Office of
the Mayor; by Townscape, Inc., Honolulu, HI, September 2004.
“Growing Coffee in Hawaii,” prepared for University of Hawaii at Manoa, College of Tropical
Agriculture and Human Resources; by H. C. Bittenbender and Virginia Easton Smith, 2004.
“Guidelines on Rainwater Catchment Systems for Hawaii,” prepared for University of Hawaii at
Manoa, College of Tropical Agriculture and Human Resources; by Patricia S. H. Macomber,
2004.
REFERENCES
Page R-2
Hawaii County
Water Use and Development Plan Update
“Hawaii County General Plan,” prepared by County of Hawaii, Planning Department, February
2005.
“Hawaii County Water Use and Development Plan,” prepared for State of Hawaii, Department
of Land and Natural Resources, Commission on Water Resource Management; by Megumi Kon,
Inc., December 1991.
“Kau River Basin Study,” prepared for County of Hawaii and Kau Soil and Water Conservation
District; by U.S. Department of Agriculture, Soil Conservation Service, Honolulu, HI, February
1994.
“North Kohala Community Development Plan,” prepared for County of Hawaii; by Phillips,
Brandt, Reddick Assoc. (Hawaii), Inc., November 1984.
“North Kona Water Master Plan, Final Report,” prepared for State of Hawaii, Department of
Land and Natural Resources, Division of Water and Land Development; by Fukunaga &
Associates, Inc., Honolulu, HI, June 1995.
“Reassessment of Ground-Water Recharge and Simulated Ground-Water Availability for the
Hawi Area of North Kohala, Hawaii, Water-Resources Investigations Report 02-4006,” prepared
by U.S. Department of the Interior, U.S. Geological Survey, Honolulu, HI, 2002.
“South Kona Water Master Plan,” prepared for County of Hawaii, Department of Water Supply;
by Fukunaga & Associates, Inc., Honolulu, HI, March 1999.
“South Kona Watershed Irrigation System Preliminary Feasibility Study,” prepared for U.S.
Department of Agriculture, Natural Resource Conservation Service, and State of Hawaii,
Department of Agriculture; by Belt Collins Hawaii, Ltd., Honolulu, HI, with Dr. Richard Bowen
and Dr. Kent Fleming, December 2003.
“Special Report #2, Water Resources, Island of Hawaii,” prepared for State of Hawaii,
Department of Hawaiian Home Lands; by Megumi Kon, Inc., Hilo, HI, April 2002.
“State Water Projects Plan, Volume 2: SWPP for Island of Hawaii,” prepared for State of
Hawaii, Department of Land and Natural Resources, Commission on Water Resource
Management; by Fukunaga & Associates, Inc., Honolulu, HI, February 2003.
“The State of Hawaii Data Book 2005, a Statistical Abstract,” prepared by State of Hawaii,
Department of Business, Economic Development & Tourism, 1995.
“Water Resources Data, Hawaii and other Pacific Areas, Water Year 2003, Water-Data Report
HI-03-1, Volume 1. Hawaii,” prepared by U.S. Department of the Interior, U.S. Geological
Survey, in cooperation with State of Hawaii, Department of Land and Natural Resources,
Commission on Water Resource Management, Honolulu, HI, 2005.
REFERENCES
Page R-3
Hawaii County
Water Use and Development Plan Update
“Water Resources Protection Plan, Volumes 1 and 2,” prepared for State of Hawaii, Department
of Land and Natural Resources, Commission on Water Resource Management; by George A.L.
Yuen and Associates Inc., June 1990.
“Well Development Plan – Phase 1, Well Source Report for Ocean View at Kahuku, Hawaii,”
prepared for Ocean View Water Committee; by Waimea Water Services, Inc., Kamuela, HI,
March 1997.
APPENDIX A
County of Hawaii General Plan
February 2005
Goals and Policies
APPENDIX A: County of Hawaii, General Plan 2005, Goals and Policies
Page A-1
Hawaii County
Water Use and Development Plan Update
The following list includes only the goals and policies pertinent to the County of Hawaii Water
Use and Development Plan.
A.1 ECONOMIC
A.1.1 Economic Goals:
(a) Provide residents with opportunities to improve their quality of life through economic
development that enhances the County’s natural and social environments.
(b) Economic development and improvement shall be in balance with the physical, social,
and cultural environments of the island of Hawaii.
(c) Strive for diversity and stability in the economic system.
(d) Provide an economic environment that allows new, expanded, or improved economic
opportunities that are compatible with the County’s cultural, natural and social
environment.
(e) Strive for an economic climate that provides its residents an opportunity for choice of
occupation.
(f) Strive for diversification of the economy by strengthening existing industries and
attracting new endeavors.
(g) Strive for full employment.
(h) Promote and develop the island of Hawaii into a unique scientific and cultural model,
where economic gains are in balance with social and physical amenities. Development
should be reviewed on the basis of total impact on the residents of the County, not only in
terms of immediate short run economic benefits.
A.1.2 Economic Policies:
(a) Assist in the expansion of the agricultural industry through the protection of important
agricultural lands, development of marketing plans and programs, capital improvements
and continued co-operation with appropriate State and Federal agencies.
(b) Encourage the expansion of the research and development industry by working with and
supporting the University of Hawaii at Hilo and West Hawaii, the Natural Energy
Laboratory at Hawaii Authority and other agencies’ programs that support sustainable
economic development in the County of Hawaii.
Appendix A: County of Hawaii, General Plan 2005, Goals and Policies
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Hawaii County
Water Use and Development Plan Update
(c) Encourage the development of a visitor industry that is in harmony with the social,
physical, and economic goals of the residents of the County.
(d) Require a study of the significant cultural, social and physical impacts of large
developments prior to approval.
(e) Encourage the sustainable development of the fishing industry, various forms of
aquaculture, and other fresh and sea water-based activities.
(f) Support all levels of educational, employment and training opportunities and institutions.
(g) Capital improvements program shall improve the quality of existing commercial and
industrial areas.
(h) The land, water, air, sea, and people shall be considered as essential resources for present
and future generations and should be protected and enhanced through the use of
economic incentives.
(i) Continue to encourage the research, development and implementation of advanced
technologies and processes.
(j) Support the development of high technology industries.
(k) Continue to encourage development and utilization of by-products from alternate energy
conversion processes.
(l) Identify and encourage primary industries that are consistent with the social, physical,
and economic goals of the residents of the County.
(m) Encourage active liaison with the private sector with respect to the County’s requirements
for establishing businesses on the island.
(n) Encourage the development of the retirement industry.
(o) Promote a distinctive industry for the island of Hawaii to enable government, business
and travel industries to promote the County of Hawaii as an entity unique within the State
of Hawaii.
(p) Identify the needs of the business community and take actions that are necessary to
improve the business climate.
(q) Support research and development that would lead to the removal of marketing
restrictions on Hawaiian fruits and other perishables.
Appendix A: County of Hawaii, General Plan 2005, Goals and Policies
Page A-3
Hawaii County
Water Use and Development Plan Update
(r) Assist in the development of a film and video industry program to market Big Island sites
and co-ordinate film and video activities on the Big Island.
(s) Assist the further development of agriculture through the protection of important
agricultural lands.
(t) Assist in the promotion of the agricultural industry whose products are recognized as
being produced on the island of Hawaii.
(u) Encourage the establishment of open farmers markets to allow local agricultural
producers to market their products.
(v) Assist in the co-operative marketing and distribution endeavors to expand opportunities
for local agricultural products for export as well as to the local market.
(w) Encourage the further development of the overseas capacity of Hilo International Airport
for the exportation of agricultural crops.
(x) Encourage the health/wellness industry.
(y) Encourage new industries that provide favorable benefit-cost relationships to the people
of the County. Benefit-cost relationships include more than fiscal considerations.
A.2 ENVIRONMENTAL
A.2.1 Environemental Quality Goals:
(a) Define the most desirable use of land within the County that achieves an ecological
balance providing residents and visitors the quality of life and an environment in which
the natural resources of the island are viable and sustainable.
(b) Maintain and, if feasible, improve the existing environmental quality of the island.
(c) Control pollution.
A.2.2 Environmental Quality Policies (Applicable to Water):
(a) Take positive action to further maintain the quality of the environment.
(b) Reinforce and strengthen established standards where it is necessary, principally by
initiating, recommending, and adopting ordinances pertaining to the control of pollutants
that affect the environment.
Appendix A: County of Hawaii, General Plan 2005, Goals and Policies
Page A-4
Hawaii County
Water Use and Development Plan Update
(c) Advise the public of environmental conditions and research undertaken on the island’s
environment.
(d) Encourage the concept of recycling agricultural, industrial, and municipal waste material.
(e) Encourage the State to establish air and water quality monitoring stations in areas of
existing and potential urban growth.
(f) Participate in watershed management projects to improve stream and coastal water
quality and encourage local communities to develop such projects.
(g) Work with the appropriate agencies to adopt appropriate measures and provide incentives
to control point and non-point sources of pollution.
(h) Require golf courses to implement best management practices to limit leaching of
nutrients to groundwater in areas where they may affect streams or coastal ecosystems.
(i) Require implementation of the management measures contained in Hawaii’s Coastal
Nonpoint Pollution Control Program as a condition of land use permitting.
(j) Review the County grading and grubbing ordinances to ensure that they adequately
address potential erosion and runoff problems.
A.3 NATURAL RESOURCES
A.3.1 Natural Resources Goals (Applicable to Water):
(a) Protect and conserve the natural resources from undue exploitation, encroachment and
damage.
(b) Protect and effectively manage Hawaii’s open space, watersheds, shoreline, and natural
areas.
(c) Ensure that alterations to existing land forms, vegetation, and construction of structures
cause minimum adverse effect to water resources, and scenic and recreational amenities
and minimum danger of floods, landslides, erosion, siltation, or failure in the event of an
earthquake.
A.3.2 Natural Resources Policies (Applicable to Water):
(a) Encourage a program of collection and dissemination of basic data concerning natural
resources.
(b) Co-ordinate programs to protect natural resources with other governmental agencies.
Appendix A: County of Hawaii, General Plan 2005, Goals and Policies
Page A-5
Hawaii County
Water Use and Development Plan Update
(c) Encourage public and private agencies to manage the natural resources in a manner that
avoids or minimizes adverse effects on the environment and depletion of energy and
natural resources to the fullest extent.
(d) Encourage an overall conservation ethic in the use of Hawaii’s resources by protecting,
preserving, and conserving the critical and significant natural resources of the County of
Hawaii.
(e) Encourage the protection of watersheds, forest, brush, and grassland from destructive
agents and uses.
(f) An identification of forest lands suitable for watershed purposes should be conducted
jointly by County, appropriate State and Federal agencies, and private landowners.
(g) Encourage appropriate State agencies to review and designate forest and watershed areas
into the conservation district during State land use boundary comprehensive reviews.
(h) Ensure that activities authorized or funded by the County do not damage important
natural resources.
(i) Within the Kona high rainfall/fog-drip belt, ground disturbing activities such as excessive
soil compaction and excessive removal of vegetative cover should be minimized and
mitigated consistent with management strategies that encourage the retention of existing
forested and pasture areas, reforestation, minimal coverage by the impervious surfaces
and other strategies that encourage effective infiltration to groundwater.
A.4 PUBLIC UTILITIES
A.4.1 Public Utilities Goals:
(a) Ensure that properly regulated, adequate, efficient and dependable public and private
utility services are available to users.
(b) Maximize efficiency and economy in the provision of public utility services.
(c) Design public utility facilities to fit into their surroundings or concealed from public
view.
A.4.2 Public Utilities Policies (Applicable to Water):
(a) Water system improvements shall correlate with the County’s desired land use
development system.
(b) All water systems shall be designed and built to Department of Water Supply standards.
Appendix A: County of Hawaii, General Plan 2005, Goals and Policies
Page A-6
Hawaii County
Water Use and Development Plan Update
(c) Improve and replace inadequate systems.
(d) Water sources shall be adequately protected to prevent depletion and contamination from
natural and man-made occurrences of events.
(e) Water system improvements should first be installed in areas that have established needs
and characteristics, such as occupied dwellings, agricultural operations and other uses, or
in areas adjacent to them if there is need for urban expansion.
(f) A co-ordinated effort by County, State and private interests shall be developed to identify
sources of additional water supply and be implemented to ensure the development of
sufficient quantities of water for existing and future needs of high growth areas and
agricultural production.
(g) The fire prevention systems shall be co-ordinated with water distribution systems in order
to ensure water supplies for fire protection services.
(h) Develop and adopt standards for individual water catchment units.
(i) Co-operate with the State Department of Health to develop standards and/or guidelines
for the construction and use of rainwater catchment systems to minimize the intrusion of
any chemical and microbiological contaminants.
(j) Co-operate with appropriate State and Federal agencies and the private sector to develop,
improve and expand agricultural water systems in appropriate areas on the island.
(k) Promote the use of ground water sources to meet State Department of Health water
quality standards.
(l) Continue to participate in the United States Geological Survey’s exploratory well drilling
program.
(m) Seek State and Federal funds to assist in financing projects to bring the County into
compliance with the Safe Drinking Water Act.
(n) Develop and adopt a water master plan that will consider water yield, present and future
demand, alternative sources of water, guidelines and policies for the issuing of water
commitments.
(o) Expand programs to provide for agricultural irrigation water.
Appendix A: County of Hawaii, General Plan 2005, Goals and Policies
Page A-7
Hawaii County
Water Use and Development Plan Update
A.5 LAND USE
A.5.1 Land Use Goals:
(a) Designate and allocate land uses in appropriate proportions of mix and in keeping with
the social, cultural, and physical environments of the County.
(b) Protect and encourage the intensive and extensive utilization of the County’s important
agricultural lands.
(c) Protect and preserve forest, water, natural and scientific reserves and open areas.
A.5.2 Land Use Policies (Applicable to Water):
(a) Zone urban-types of uses in areas with ease of access to community services and
employment centers and with adequate public utilities and facilities.
(b) Promote and encourage the rehabilitation and use of urban areas that are serviced by
basic community faculties and utilities.
(c) Allocate appropriate requested zoning in accordance with the existing or projected needs
of neighborhood, community, region and County.
(d) Encourage urban development within existing zoned areas already served by basic
infrastructure, or close to such areas, instead of scattered development.
APPENDIX B
CWRM
Island of Hawaii
Well Database
(as of October 2005)
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgdHAWI AQUIFER SYSTEM [80101]80101 7345-01 Aamakoa Gu TH 2 Kohala Sugar ROT 3 171 255 UNU 1964 73 6.8 25 3780101 7549-02 Alaalae Gu TH-7 Kohala Sugar ROT 3 362 84 UNU 1965 73 5.2 25 2580101 7549-01 Alaalae Shaft Kohala Sugar DUG 75 UNU 1900 4680101 7145-05 Amau Tunnel Kohala Sugar TUN 1000 IRR 1939 4680101 7247-01 Bond 1 Tunnel Hawaii Dws TUN 978 MUN 1937 46 5-3-005:028 70080101 7247-02 Bond 2 Tunnel Kohala Sugar TUN 1450 MUN 1934 4680101 7148-01 Cowpen 1 Tunnel Kohala Sugar TUN 1700 IRR 4680101 7148-02 Cowpen 2 Tunnel Kohala Sugar TUN 1740 IRR 4680101 7148-03 Cowpen 3 Tunnel Kohala Sugar TUN 1740 IRR 4680101 7248-01 Dr Bond Tunnel Kohala Sugar TUN 968 IRR 7480101 7448-03 Gusman Gu TH 5 Kohala Sugar ROT 3 306 402 UNU 1964 73 6.2 12 3380101 7347-02 Halaula Kohala Sugar PER 16 342 505 IND 1948 72 7.8 26 43 120080101 7347-05 Halaula B U S G S ROT 10 628 730 OBS 1989 89 11.4 19 5-3-004:80101 7347-03 Halaula Makai E U S G S ROT 8 341 405 OBS 1989 89 9.8 5-3-004:00580101 7347-04 Halaula Mauka B U S G S ROT 8 630 730 OBS 1989 89 11.4 5-3-004:80101 7346-01 Halawa Gu TH 1 Kohala Sugar ROT 3 170 267 UNU 1964 73 7.4 54 54 5-3-008:02680101 7246-01 Halawa Tunnel Kohala Sugar TUN 1000 IRR 1938 4680101 7248-03 Hapahapai Tunnel Hawaii Dws TUN 1350 MUN 1935 46 5-3-001:009 3580101 7445-01 Hapuu Bay D U S G S ROT 8 109 460 OBS 1989 89 7.2 5-3-007:01080101 7449-01 Hawi Kohala Sugar TUN 500 84 UNU 189880101 7449-02 Hawi 1 Hawaii Dws PER 12 542 591 MUN 1975 5-5-002:089 400 0.29 0.6480101 7349-01 Hawi 2 Hawaii Dws ROT 18 791 847 MUN 1993 97 7.16 20 5-5-016:018 700 0.25 0.6580101 7549-03 Hawi Makai I U S G S ROT 10 299 436 OBS 1989 89 2.280101 7449-03 Hawi Obs H U S G S ROT 8 541 585 OBS 1989 89 7 21 5-5-002:02380101 7650-01 Hoea Shaft Kohala Sugar SHF 52 61 UNU 1900 74 2 87580101 7448-07 Honopueo F U S G S ROT 10 415 429 OBS 1989 89 8 36 5-4-004:80101 7347-01 Iole-Bond Tunnel Kohala Sugar TUN 650 MUN 4680101 7147-05 J D Bond Tunnel Kohala Sugar TUN 1500 IRR 1935 4680101 7248-02 Kaala Tunnel Kohala Sugar TUN 1025 IRR 1934 4680101 7147-01 Kay Tunnel Kohala Sugar TUN 1700 IRR 4680101 7147-07 Koelling Tunnel Kohala Sugar TUN 1600 MUN 1937 4680101 7448-06 Kohala Obs F U S G S ROT 8 412 440 OBS 1989 89 8.21 5-4-009:00180101 7446-01 Kohala Shaft Kohala Sugar SHF 123 135 IRR 1900 3441 694080101 7348-01 Kohala Sugar Kohala Sugar TUN 900 IRR80101 7047-01 Lindsay Tunnel Hawaii Dws TUN 2150 MUN 1933 72 5-3-002:00180101 7345-05 Makapala Hawaii Dws PER 10 399 547 UNU 2002 02 8.73 40 5-2-005:01080101 7345-03 Makapala A U S G S ROT 12 396 495 OBS 1989 89 10.3 5-2-005:80101 7345-04 Makapala Obs A U S G S ROT 8 395 440 OBS 1989 89 10.2 5-2-005:01080101 7245-01 Maulua Tunnel Hawaii Dws TUN 750 MUN 1939 46 5-2-005:00180101 7147-02 Mcgill 1 Tunnel Kohala Sugar TUN 2000 SLD 4680101 7147-04 Mcgill 2 Tunnel Kohala Sugar TUN 2060 IRR 1932 4680101 7147-03 Mcgill 3 Tunnel Kohala Sugar TUN 2040 IRR 1932 4680101 7145-02 Murphy Tunnel Hawaii Dws TUN 1250 MUN 46 5-2-005:001 37Hawaii CountyWater Use and Development Plan UpdatePage B-1
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80101 7148-05 Olding Tunnel Kohala Sugar TUN 1600 IRR 4680101 7145-04 Paa Tunnel Kohala Sugar TUN 1200 IRR 1939 4680101 7248-04 Pahei Tunnel Kohala Sugar TUN 1000 IRR 1939 4680101 7145-03 Puu Mini Tunnel Kohala Sugar TUN 1200 MUN 1937 4680101 7448-01 Union Mill Kohala Sugar ROT 4 420 425 UNU 1898 6880101 7448-04 Union Mill 1 Kohala Sugar PER 16 311 412 IND 1965 72 7 47 73 185080101 7448-05 Union Mill 2 Kohala Sugar PER 16 420 522 IND 1969 72 129 185080101 7451-02 Upolu J-B U S G S ROT 10 567 632 OBS 1989 89 4.2 5-5-006:00380101 7451-01 Upolu Obs J-A U S G S ROT 8 567 632 OBS 1989 89 4.2 5-5-006:00380101 7552-01 Upolu TH 6 Kohala Sugar ROT 3 293 360 UNU 1964 73 2.8 349 155080101 7652-01 Waikane Shaft Kohala Sugar SHF 33 42 IRR 1920 66 208080101 7345-02 Waikani Gu TH 3 Kohala Sugar ROT 3 161 265 UNU 1964 73 25 2980101 7145-01 Waikani Tunnel Kohala Sugar TUN 1500 MUN 4680101 7146-01 Waipunalau Tunnel Kohala Sugar TUN 1600 MUN 1934 4680101 7148-04 Watt 1 Tunnel Hawaii Dws TUN 1750 MUN 72 14 5-3-001:00880101 7147-06 Watt 2 Tunnel Kohala Sugar TUN 1700 IRR 1936 46Total - Hawi Aquifer System [80101]0.54 1.29WAIMANU AQUIFER SYSTEM [80102]80102 6843-04 Honokane TH 2 Kohala Ditch ROT 2 1031 90 196480102 6843-06 Honokane 1 State Doa80102 6843-07 Honokane 3 State Doa 197680102 6843-01 Honokane Nui Tun Kohala Sugar TUN 1535 IRR 193280102 6843-02 Honokane Nui Tun Kohala Sugar TUN 1229 IRR 193280102 6843-03 Honokane Nui Tun Kohala Sugar TUN 950 IRR 193280102 6844-01 Honokane TH 1 Kohala Ditch ROT 2 965 150 UNU 1964 7380102 6843-05 Honokane TH 3 Kohala Ditch ROT 2 1050 300 UNU 1964 7380102 6743-02 Honokane TH 4 Kohala Ditch ROT 2 1196 150 UNU 1964 7380102 6743-01 Honokane Tunnel Kohala Sugar TUN 1900 IRR 1941 7280102 6340-05 Kohala TH 1 State Land ROT 6 103 LOS 198780102 6440-02 Kohala TH 3 State Land ROT 2 160 LOS 198780102 6440-01 Kohala TH 4 State Land ROT 130 LOS 198780102 6440-03 Kohala TH 5 State Land ROT 2 105 LOS 1987801026734-01 Kukuihaele A Hawaii Dws MUN 1966 4-8-007:030 100 0.00 0.0080102 6536-01 Lalakea Gulch Tu Kohala Sugar TUN 2200 UNU 4680102 7144-01 Opaepilau 1 Tunn Kohala Sugar TUN 1100 OTH 1934 4680102 7144-02 Opaepilau 2 Tun Kohala Sugar TUN 1182 IRR 1934 4680102 7244-01 Pae Tunnel Kohala Sugar TUN 720 IRR 1937 4680102 6745-01 Puu Laalaau TH Kahua Ranch 14 3950 151 UNU 1962 72 5-9-002:00180102 6337-01 Puukapu State Land ROT 16 3023 1744 MUN 1987 96 1740 9 6-3-001:004 100080102 6337-02 Puukapu Shallow State Land PER 12 3020 355 UNU 1993 93 6-3-001:004Total - Waimanu Aquifer System [80102]0.00 0.00MAHUKONA AQUIFER SYSTEM [80103]Hawaii CountyWater Use and Development Plan UpdatePage B-2
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80103 6249-01 Akau 1 Akau H ROT 4 25 30 IRR 1981 81 6-1-002:061 2780103 6752-01 Heffner 1 Heffner C ROT 6 162 169 UNU 1999 99 1.5 2500 5-8-001:009 080103 6550-01 Kahua Max Sherrod PER 8 675 700 IRR 1986 86 3.7 260 5-9-008:006 2180103 6853-01 Kaiholena 1 Kaiholena LLC ROT 8 405 415 IRR 2000 00 0.85 3000 5-8-001:016 6080103 6448-01 Kawaihae State Dowrm ROT 1341 1465 UNU 1990 90 1 2500 6-1-001:00380103 6250-02 Kawaihae HELCO 4 49 180 SLD 1974 98 6-1-006:00380103 6147-01 Kawaihae 3 State Dowald ROT 8 982 1046 UNU 1963 73 4.6 22980103 6250-01 Kawaihae TH HELCO ROT 1 78 500 SLD 1974 9880103 6549-03 Kawaihae-DHHL State DHHL ROT 18 1651 1700 UNU 1992 92 6.3 6-1-001:00380103 6451-02 Kawamata 1 Kawamata N PER 6 238 245 IRR 1987 87 2.6 1235 1245 5-9-005:015 4080103 6451-03 Kawamata 2 Kawamata N PER 6 395 405 IRR 1987 87 6.7 700 700 5-9-006:008 4580103 6340-01 Kohakohau TH 1 State Dowald ROT 3 3910 100 OTH 1964 7380103 6340-02 Kohakohau TH 2 State Dowald ROT 3 3850 100 OTH 1964 7380103 6340-03 Kohakohau TH 3 State Dowald ROT 3 3770 100 196480103 6341-02 Kohakohau TH 4 State Dowald ROT 3 3790 100 OTH 1964 7380103 6341-03 Kohakohau TH 5 State Dowald ROT 3 3850 100 OTH 1964 7380103 6450-01 Kohala Estates Place V A PER 4 395 412 UNU 1980 80 1320 5-9-006:00980103 6549-01 Kohala Ranch 1 Kohala J V ROT 12 1460 1550 MUN 1979 86 7.25 25 653250.32 0.4380103 6549-02 Kohala Ranch 2 Kohala J V ROT 12 1449 1560 MUN 1982 86 70 5-9-001:010 700 0.36 0.4180103 6649-01 Kohala Ranch 3 Kohala J V ROT 18 1840 1925 UNU 1989 136 5-9-010:04480103 6649-02 Kohala Ranch 4 Kohala J V ROT 18 1746 1830 UNU 1993 17.7 5-9-013:08580103 6340-04 Kohala TH 2 State Land ROT 6 105 LOS 1987801037352-01 Kukuipahu A Kukuipahu Ranch ROT 6 800 830 UNU 2003 03 2.95 275 5-6-001:019 080103 6148-03 M Kea Bch M Kea Bch Htl OTH80103 7154-01 Mahukona Hawaii R R Co PER 25 800 OTH 1881 4680103 7352-02 Miller 1 Miller L ROT 8 475 493 DOM 2004 05 2.57 340 5-6-001:111 15080103 6953-02 Paoo-Gordy Gordy D PER 6 148 155 UNU 2001 01 1.53 5-7-001:020 080103 6953-01 Paoo-Reardon Reardon M PER 6 37 40 IRR 1986 86 0.1 5600 5-7-001:005 2580103 6239-02 Parker Ranch 1 R Smart Trust ROT 14 2822 1679 UNU 1994 94 1264 7 6-4-001:05080103 6341-01 Waiaka Gulch TH State Dowald ROT 3 3613 924 OTH 1964 7380103 6141-01 Waiakaa Tank U S G S ROT 4 2506 1507 OBS 1999 99 1243 6-6-001:07080103 6451-01 Waiakailio TH Kahua Ranch ROT 2 60 90 UNU 1963 7280103 6450-04 Waika-Fischer Fischer P & S PER 6 653 670 IRR 1996 96 2 230 5-9-008:019 1680103 6450-05 Waika-Keanaholu Place Virgil A PER 8 370 383 IRR 1996 96 2.81 960 5-9-005:005 4880103 6238-01 Waimea U S Government PER 8 2855 890 UNU 1944 4480103 6240-02 Waimea Exploratory State Dlnr ROT 16 2969 2000 UNU 2000 00 1263 6 6-5-001:00380103 6240-01 Waimea Obs. U S G S ROT 4 2970 2016 OBS 1991 91 6-5-001:00380103 6450-02 Walsh Lot 39 Walsh B T PER 12 801 835 IRR 1984 5-9-007:004 80Total - Mahukona Aquifer System [80103]0.68 0.84HONOKAA AQUIFER SYSTEM [80201]80201 6331-01 Ahualoa Plant U S G S ROT 12 1725 SLD 2004 04 4-6-011:038 080201 6528-02 Enserch 1 Hamakua Energy ROT 14 450 486 IND 1998 00 3.46 145 4-5-002:023 700 0.42 0.7880201 6528-03 Enserch 2 Hamakua Energy ROT 12 451 491 IND 2000 01 2.71 85 4-5-020:056 700 0.48 0.90Hawaii CountyWater Use and Development Plan UpdatePage B-3
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80201 6528-01 Haina Hawaii Dws ROT 12 855 909 MUN 1979 83 4.51 57 4-5-002:048 400 0.37 0.41802016428-01 Honokaa A State Dowald 14 1452 OBS 1993 96 12 4-5-019:020 0802016428-02 Honokaa B State Land Division ROT 14 1335 1800 UNU 2003 03 42 100 4-5-019:020 0 0.00 0.0080201 6734-03 Kukuihaele Hawaii Dws ROT 12 955 1005 MUN 2002 02 5.78 450 4-8-008:026 0 0.00 0.0080201 6235-01 Waimea C C Otaka Inc ROT 14 2814 1415 IRR 1991 92 1657 4-7-007:007 500 0.03 0.05Total - Honokaa Aquifer System [80201]1.30 2.14PAAUILO AQUIFER SYSTEM [80202]80202 6424-01 Hamakua 2 Hamakua Sugar UNU 4-4-002:00480202 5917-01 Humuula Tunnel Laupahoehoe Su TUN 1600 UNU80202 6016-01 Island Dairy Island Dairy Inc ROT 8 538 600 UNU 2001 01 10.07 60 3-9-001:002 080202 5816-02 Kaawalii Gu Tun1 Laupahoehoe Su TUN 2010 UNU80202 5816-03 Kaawalii Gu Tun2 Laupahoehoe Su TUN 2000 UNU80202 5816-01 Kaawalii Tunnel Laupahoehoe Su TUN 2000 UNU 4680202 6121-02 Kainehe Str Tun Laupahoehoe Su TUN 1200 UNU80202 6122-01 Kanui Gulch Tun Laupahoehoe Su TUN 1350 UNU80202 6017-01 Kaula Gulch Tun1 Laupahoehoe Su TUN 1200 UNU80202 6017-02 Kaula Gulch Tun2 Laupahoehoe Su TUN 1200 UNU80202 6017-03 Kaula Gulch Tun3 Laupahoehoe Su TUN 1200 UNU80202 6017-04 Kaula Gulch Tun4 Laupahoehoe Su TUN 640 UNU80202 6121-01 Kawaiili Str Tun Laupahoehoe Su TUN 1500 UNU80202 6220-01 Kukaiau Laupahoehoe Su 12 245 265 UNU80202 6222-01 Manienie Gu Tun Laupahoehoe Su TUN 700 UNU 83280202 6017-05 Ookala Hawaii Dws ROT 12 641 700 MUN 1995 96 7.67 10 3-9-001:034 250 0.03 0.0680202 6117-01 Ookala Shaft Laupahoehoe Su SHF 300 600 IND 1937 72 6 10 279 250080202 6322-01 Paauilo Laupahoehoe Su PER 12 175 UNU 1894 4680202 6122-02 Paauilo Gu Tun Laupahoehoe Su TUN 1540 UNU80202 6122-03 Paauilo Gu Tun Laupahoehoe Su TUN 1580 UNU80202 6321-01 Paauilo Mill Laupahoehoe Su PER 12 215 217 UNU 189480202 6321-02 Paauilo Shaft Laupahoehoe Su SHF 273 626 IRR 1944 02 3 60 320 4-3-001:002 70080202 6222-02 Paauilo Str Tun Laupahoehoe Su TUN 1060 UNU80202 6222-03 Paauilo Str Tun Laupahoehoe Su TUN 700 UNU80202 6223-01 Paauilo-DWS Hawaii Dws ROT 12 1054 1148 MUN 1985 94 11.6 4-3-007:006 300 0.09 0.1580202 6119-01 Puumaile Str Tun Laupahoehoe Su TUN 800 UNU80202 6120-01 Puumaile Str Tun Laupahoehoe Su TUN 1075 UNU80202 6120-02 Puumaile Str Tun Laupahoehoe Su TUN 1075 UNU80202 6120-03 Puumaile Str Tun Laupahoehoe Su TUN 850 UNU80202 6323-01 Slaughter House Hamakua Sugar PER 14 509 575 IND 1987 4-3-005:002 950Total - Paauilo Aquifer System [80202]0.12 0.21HAKALAU AQUIFER SYSTEM [80203]80203 5206-02 Buyers Buyers J W A ROT 5 89 105 DOM 1997 03 39.38 16 2-8-015:001 1580203 5005-03 Cooling 1 Hilo Cst Proc PER 26 77 381 IND 1971 72 8 110 9000 2-8-007:001 520080203 5005-04 Cooling 2 Hilo Cst Proc PER 26 74 375 IND 1972 72 6.83 372 9000 2-8-007:001 5200Hawaii CountyWater Use and Development Plan UpdatePage B-4
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80203 5005-05 Cooling 3 Hilo Cst Proc PER 26 76 380 IND 1972 72 6.8 285 9000 2-8-007:001 520080203 5307-01 Hakalau School Hawaii Dws PER 10 235 317 MUN 1976 11.9 10 2-9-002:005 50 0.00 0.0080203 Honomu Hawaii Dws UNU 2005 05 2-8-013:05580203 5716-01 Kapili Str Tun Laupahoehoe Su TUN 2075 UNU 4680203 5206-03 Kiko 1 Parisi C PER 6 110 UNU 2004 04 2-8-013:010 0 0.00 0.0080203 5814-01 Laupahoehoe 1 Hawaii Dws ROT 10 659 700 MUN 1968 72 5.93 115 128 3-6-003:035 100 0.01 0.1180203 5814-02 Laupahoehoe 2 Hawaii DWS ROT 12 665 711 MUN 1979 83 3-6-003:036 300 0.11 0.1580203 5005-02 Makai Dom Hilo Cst Proc PER 18 247 309 DOM 1947 72 11.03 18 22 2-8-007:001 25080203 5005-01 Mauka Dom Hilo Cst Proc PER 13 304 333 DOM 1946 11.43 16 2-8-007:001 50080203 5307-02 Wailea-Hamakua C Santos R J ROT 4 101 130 1981 80 2-9-003:00180203 5307-03 Wailea-Mccully Mccully J W ROT 5 163 182 IRR 1994 94 72.5 2-9-003:013 25Total - Hakalau Aquifer System [80203]0.12 0.26ONOMEA AQUIFER SYSTEM [80204]80204 4606-01 Honolii Str Tun M Kea Sugar Co TUN 57580204 4708-03 Kaieie Mauka Hawaii Dws ROT 14 1130 1300 UNU 2002 02 27 3 120 2-7-002:003 0.00 0.0080204 4708-02 Kaieie Mauka U S G S ROT 4 1134 1030 OBS 1999 99 2-7-002:00380204 4708-01 Kapue Stream Tun Mauna Kea Agri TUN 1275 UNU80204 4906-01 Kawainui Str Tun Mauna Kea Agri TUN 600 OTH 89 2-7-007:00180204 4806-01 Kim 1 Kim Y S ROT 6 402 420 UNU 2001 01 19.8 20 2-7-009:017 080204 5006-01 Kulaimano Hawaii Dws PER 12 378 492 MUN 1976 12.29 7 2-8-007:076 300 0.18 0.2180204 4905-02 Lutkenhouse Lutkenhouse D PER 5 152 162 IRR 1993 93 26.2 20 2-7-010:001 2080204 4805-01 Onomea 1 Rogers H ROT 6 319 350 DOM 1998 98 21.4 15 2-7-010:003 1680204 4905-01 Onomea-Doty Doty J PER 8 256 308 DOM 1990 10 2-7-010:027 10080204 4607-01 Pahoehoe Str Tun Mauna Kea Agri TUN 900 UNU80204 4706-01 Papaikou Hawaii Dws PER 12 369 425 MUN 1972 21 4 15 2-7-037:0443750.20 0.23Total - Onomea Aquifer System [80204]0.38 0.44WAIMEA AQUIFER SYSTEM [80301]80301 6049-06 Arlin Trust Arlin Trust PER 8 92 111 IRR 1996 02 2.32 830 6-2-002:024 40 0.01 0.0280301 5949-01 Camp Drewes U S MC DUG 90 UNU 1944 56080301 6047-04 Hapuna 3 Mauna Kea Properties ROT 12 720 765 IRR 2003 04 4.94 200 6-2-001:051 45080301 5948-01 Hapuna Bch Park State Parks ROT 10 244 268 IRR 1970 73 2.6 43080301 6049-07 Hoffee Hoffee J ROT 8 54 157 OTH 2000 00 6-2-014:001 45080301 6148-01 Kawaihae 1 Hawaii Dws PER 10 583 601 MUN 1961 74 4.4 302 385 6-2-001:061 15080301 6048-01 Kawaihae 2 Mauna Kea Prop PER 10 392 430 UNU 1961 73 3.3 504 6-2-013:01480301 6148-02 Kawaihae 4 Hawaii Dws ROT 10 583 601 MUN 1969 72 4.4 330 460 6-2-001:061 45080301 5946-01 Lalamilo A Hawaii Dws ROT 12 1172 1277 MUN 1977 8.2 78 6-6-001:068 700 0.04 0.2180301 5946-02 Lalamilo B Hawaii Dws ROT 16 1088 1164 MUN 1980 81 6.6 32 6-6-001:066 1000 0.69 1.2580301 5946-03 Lalamilo C Hawaii Dws ROT 16 1087 1158 MUN 1980 81 7.6 55 6-6-001:067 1000 0.49 0.7880301 5946-04 Lalamilo D Hawaii DWS PER 16 1085 1144 MUN 1985 89 7 60 6-6-001:069 1000 0.00 0.0080301 6049-04 M Kea Bch M Kea Bch Htl PER 18 82 93 OTH 1971 7280301 6048-02 M Kea Bch Htl 1 Mauna Kea Prop ROT 10 340 376 IRR 1963 72 4.5 75080301 6049-01 M Kea Bch Htl 2 Mauna Kea Prop PER 12 188 218 IRR 1963 72 2 700 6-2-001:056Hawaii CountyWater Use and Development Plan UpdatePage B-5
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80301 6049-02 M Kea Bch Htl 3 M Kea Bch Htl PER 14 40 76 IND 1960 72 280080301 6049-03 M Kea Bch Htl 4 M Kea Bch Htl ROT IND 1972 72 525080301 5849-02 Mauna Lani 8 Mauna Lani Resort ROT 12 147 165 IRR 1999 02 2.85 6-8-001:052 55080301 5849-03 Mauna Lani 9 Mauna Lani Resort ROT 12 143 161 IRR 1999 02 6-8-001:052 45080301 5749-01 North Mauna Lani Res ROT 12 93 100 IRR 1991 92 2 600 6-8-001:052 450 0.62 1.4980301 6046-01 Ouli 1 Nansay Haw Inc ROT 14 1302 1400 UNU 1989 89 13.6 6-2-001:7580301 6049-05 Ouli A Mauna Kea Prop PER 14 300 340 UNU 1979 3.2 6-2-001:01980301 6048-03 Ouli B Mauna Kea Prop PER 14 315 347 UNU 1980 2.9 6-2-001:07880301 6047-01 Ouli C Mauna Kea Prop ROT 12 724 764 IRR 1990 93 4.6 6-2-001:051 45080301 6047-02 Ouli D Mauna Kea Prop ROT 12 706 758 IRR 1991 92 4.3 6-2-001:051 45080301 5745-02 Parker 4 Waikoloa Water ROT 12 1203 1231MUN1969 73 16 30 30 6-8-002:0198000.50 0.7480301 5745-01 Parker 5 Waikoloa Water ROT 12 1207 1242MUN1969 73 16 30 30 6-8-002:0198000.77 1.2280301 4534-01 Pohakuloa TH State Dowald ROT 3 6000 350 UNU 1969 7280301 5849-01 Puako 3 Parker Ranch DUG 66 27 IRR 6480301 5239-01 Waikii 1 Waikii Ranch ROT 13 4260 4350MUN1983 87 1509 18 6-7-001:003 100 0.03 0.0580301 5239-02 Waikii 2 Waikii Ranch ROT 6 4260 3300MUN1988 88 1280 6-7-001:003 100 0.01 0.0480301 5745-03 Waikoloa 1 Waikoloa Water PER 16 1196 1330 MUN 1988 89 17 30 30 6-8-002:01914000.86 2.0780301 5546-01 Waikoloa 2 Waikoloa Water ROT 16 1193 1317 MUN 1989 91 8 70 6-8-002:017 1000 0.99 1.2180301 5546-02 Waikoloa 3 Waikoloa Water ROT 16 1217 1285 MUN 1991 97 7.23 25 6-8-002:017 1000 1.38 1.6580301 5545-01 Waikoloa DW-6 West Hawaii Water Co. ROT 16 1319 1390 UNU 2004 04 6.8 85 6-8-002:017 080301 5846-01 Waikoloa MLR 1 Mauna Lani Res ROT 20 1147 1242 MUN 1992 99 6-8-001:04610001.711.6980301 5846-02 Waikoloa MLR 2 Mauna Lani Res ROT 20 1178 1275 MUN 1993 98 6.3 6-8-001:04510001.52 1.69Total - Waimea Aquifer System [80301]9.62 14.11HILO AQUIFER SYSTEM [80401]80401 4203-13 Glover Quarry A Jas Glover Ltd DUG 72 23 25 IND 1948 84 13 60080401 4203-14 Glover Quarry B Jas Glover Ltd DUG 72 23 25 IND 1948 84 13 35080401 4203-12 Helco Kan 6-4 HELCO ROT 30 49 210 IND 1974 74 6 2-2-058:019 625080401 4203-05 Hill Unit 5A HELCO 29 50 200 IND 1965 72 28 2-2-058:019 4500 14.90 19.4580401 4203-06 Hill Unit 5B HELCO 29 50 200 IND 1965 72 6.5 24 2-2-058:019 450080401 4203-07 Hill Unit 5C HELCO 29 50 585 IND 1965 72 2-2-058:019 450080401 4203-09 Hill Unit 6A HELCO ROT 32 55 210 IND 1974 74 6 2-2-058:019 625080401 4203-10 Hill Unit 6B HELCO ROT 32 55 210 IND 1973 74 6 2-2-058:019 6250 21.78 27.0080401 4203-11 Hill Unit 6C HELCO DUG 72 43 20 OTH 1974 6 2-2-058:01980401 4202-01 Hilo Airport 1 HIARNG PER 16 59 76 UNU 1944 50 4 186 2-1-012:02980401 4202-02 Hilo Airport 2 HIARNG PER 71 55 UNU 1944 50 5 2-1-012:13180401 4203-08 Kanoelehua Disp HELCO DUG 192 39 33 OTH 1965 7280401 4010-01 Kaumana U S G S ROT 4 1796 1397 OBS 1995 95 996.8 2-5-002:02480401 4211-01 Olaa Flume Tun Hawaii Dws TUN 1960 MUN 73 1960 2-5-001:013 300080401 4306-01 Piihonua A Hawaii Dws PER 18 278 423 MUN 1973 42.1 2 2-3-026:009 2100 1.34 2.1780401 4306-02 Piihonua B Hawaii Dws PER 18 278 445 MUN 1987 42.3 2 2-3-026:009 2100 2.01 2.9380401 4208-01 Piihonua C Hawaii Dws PER 20 975 1032 MUN 1995 98 263.9 2 2-5-009:003 2100 1.21 1.4280401 4206-01 Ponohawai 3 Isf Develop Co PER 12 380 465 UNU 1993 93 243 2-3-044:00980401 4110-01 Saddle Road A Hawaii Dws ROT 20 1910 1400 MUN 1998 02 950.6 2 2-5-041:047 700 0.39 0.44Hawaii CountyWater Use and Development Plan UpdatePage B-6
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80401 4304-01 Shipman 1A, 1B HELCO 54 12 20 IND 1943 72 2-1-001:024 saltwater80401 4304-02 Shipman 2 HELCO DUG 84 10 26 UNU 1957 83 2-1-001:02480401 4304-03 Shipman 3 HELCO DUG 10 20 IND 1971 72 2-1-001:024 saltwater 0.56 3.5380401 4304-04 Shipman 4A, 4B HELCO DUG 10 20 IND 1970 72 2-1-001:024 saltwater80401 4203-15 Waiakea Hawaiian Host PER 8 81 130 IND 1987 8.75 2180401 4203-04 Waiakea 4 HELCO PER 16 47 201 SLD 1961 72 7.06 2280401 4007-01 Waiakea Monitor Okahara & Assc ROT 7 915 955 OBS 1991 91 257.6 2-4-006:03480401 4203-01 Waiakea TH 1 HELCO 5 40 54 UNU 1960 6.7 480401 4203-02 Waiakea TH 2 HELCO 5 41 55 UNU 1960 9.1 680401 4203-03 Waiakea TH 3 HELCO 5 41 56 OTH 1960 5.8 480401 4204-01 Waiakea Village Hawn Rsrt Vill PER 14 35 IND 1971 73 700Total - Hilo Aquifer System [80401]42.19 56.94KEEAU AQUIFER SYSTEM [80402]80402 3802-06 Hawaiian Natural Hawaii Brewery Dev Co. ROT 10 226 251 DOM 1981 98 14 1-6-141:001 23080402 3800-01 Keaau W H Shipman PER 10 40 60 SLD 1950 7280402 3802-01 Keaau 1 Hawaii Dws 12 215 450 MUN 1921 72 9 1-6-003:055 1020 0.01 0.0780402 3802-02 Keaau 2 Hawaii Dws 12 215 450 MUN 1921 72 5 1-6-003:055 1000 0.13 0.2380402 3900-01 Keaau Orchard 1 Mauna Loa Mac PER 8 92 137MUN1949 67 8.5 31 13635080402 3900-02 Keaau Orchard 2 Mauna Loa Mac PER 12 95 129MUN1964 8.1 207 24850080402 3801-01 Keaau Recharge Puna Sugar DUG 120 70 OTH 7280402 3804-01 Keaau-Shipman W H Shipman PER 12 552 698 OTH 1987 87 32.8 1-6-003:007 10080402 4189-01 Kings Landing 1 Paradise Park 10 36 58 UNU 1959 72 3.4 1-6-001:02580402 4100-01 Kings Landing 2 Watumull Inv PER 10 46 54 UNU 1971 89 6 280 380 1-6-001:02580402 4002-01 Kings Landing 3 Watumull Inv PER 12 120 133 UNU 1972 72 9.7 16 1-6-001:00280402 3810-01 Middle Flume Tun Puna Sugar TUN 2100 IND 1900 4280402 3810-02 Middle Flume Tun Puna Sugar TUN 2050 IND 1900 4280402 3810-04 Middle Flume Tun Puna Sugar TUN 2150 UNU 190080402 3810-03 Middle Flume Tun Puna Sugar TUN 2150 190080402 3505-01 Mt View TH 1 ROT 1125 158 UNU 193680402 3504-01 Mt View TH 10 ROT 815 150 UNU 193680402 3308-01 Mt View TH 4 ROT 1905 117 UNU 193680402 3508-01 Mt View TH 5 ROT 1940 155 UNU 193680402 3406-01 Mt View TH 6 ROT 1445 160 UNU 193680402 3306-01 Mt View TH 7 ROT 1530 106 UNU 193680402 3603-01 Olaa 3 Hawaii Dws PER 16 602 664 MUN 1988 0 1-6-003:08712750.87 1.0580402 3702-01 Olaa Shaft Puna Sugar SHF 120 220 203 IND 1936 66 14.5 1-6-003:005 280080402 4003-01 Panaewa 1 Hawaii Dws PER 16 206 306 MUN 1963 72 13.12 8 2-2-048:00617002.10 2.4380402 4003-02 Panaewa 2 Hawaii Dws PER 18 201 302 MUN 1968 72 13.1 2-2-048:006 2200 2.14 2.5680402 4003-03 Panaewa Deep 3 Hawaii Dws PER 18 206 303 MUN 1983 85 12.2 2-2-048:006 2100 1.18 2.4880402 3802-03 Puna Plnt Pump 1 HELCO ROT 16 214 379 IND 1969 69 28 8 1-6-003:005 2800 8.28 11.0080402 3802-04 Puna Plnt Pump 2 HELCO ROT 16 214 371 IND 1969 69 19.7 8 6 1-6-003:005 280080402 3802-05 Puna Plnt Pump 3 HELCO ROT 16 214 375 IND 1969 69 8 1-6-003:005 280080402 4003-04 Toyama Gardens Toyama Gardens PER 10 195 235 IRR 1988 89 8 14 2-2-048:013Hawaii CountyWater Use and Development Plan UpdatePage B-7
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80402 3809-01 Waiakea-Uka Tun Hawaii Dws TUN 1550 MUN 1890 72 2-4-008:80402 3809-02 Waiakea-Uka Tun Hawaii Dws TUN 1560 MUN 1890 72 2-4-008:Total - Keeau Aquifer System [80402]14.71 19.82OLAA AQUIFER SYSTEM [80501]80501 3010-01 Flagg 1 Flagg C E ROT 14 2654 1537 UNU 1997 97 1491 4 1-8-011:06380501 3117-01 Kulani Prison State Of Haw PER 8 5080 80 UNU 1947 66 500080501 3207-01 Mt View TH 2 ROT 1810 58 UNU 193680501 3207-02 Mt View TH 3 ROT 1835 160 UNU 193680501 3207-03 Mt View TH 9 ROT 1685 139 UNU 193680501 3207-04 Olaa-Mt. View U S G S ROT 4 1687 1143 OBS 1995 95 1008 1-8-005:01880501 2714-03 Volcano A State Dowald PER 3802 245 SLD 1976 76 357780501 2815-02 Volcano B State Dowald PER 8 3865 365 SLD 1977 77 353280501 2715-02 Volcano TH 3 State Dowald ROT 1 3838 350 OBS 73 349580501 2815-01 Volcano TH-1 State Dowald 375 1973 1-9-001:00980501 2715-01 Volcano TH2 State Dowald ROT 3 3910 400 SLD 1973 7380501 2714-01 Volcano TH-4 State Dowald ROT 3 3802 328 OBS 1973 73 362080501 2714-02 Volcano TH5 State Dowald 3 3802 500 OBS 1976 76 3577Total - Olaa Aquifer System [80501]0.00 0.00KAPAPALA AQUIFER SYSTEM [80502]No inventory in this systemNAALEHU AQUIFER SYSTEM [80503]80503 1331-01 Alili Tunnel Hawaii Dws TUN 2900 MUN 1930 74 9-7-001:018 31080503 1530-01 Double Arch Tunn Kau Agri Co TUN 3700 IRR80503 1630-04 Fault Tunnel Kau Agri Co TUN 3500 IRR80503 1333-03 Fukuda Tunnel Kau Agri Co TUN 3000 IRR80503 1229-03 H Brothers Hester E PER 1170 UNU 2004 04 0805030537-01 Haao Tunnel Kau Agri Co TUN 2300 IRR 9-7-001:00180503 1630-03 Heio Tunnel Kau Agri Co TUN 3600 IRR80503 0533-02 Honuapo 1 Kau Agri Co PER 14 94 130 IRR 1965 2 156 580 115080503 0632-01 Honuapo 2 Kau Agri Co PER 14 103 140 UNU 1965 74 2.9 62480503 0533-03 Honuapo 3 Kau Agri Co PER 14 89 125 IRR 1965 3.2 115080503 0533-01 Honuapo Mill Kau Agri Co ROT 3 22 34 UNU 1946 74 122080503 1730-03 Horita Tunnel Kau Agri Co TUN 4150 IRR80503 1529-01 Ipuu Ridge Tun Kau Agri Co TUN 2600 IRR80503 1530-04 Kaalaala Gu Tunn Kau Agri Co TUN 3250 IRR80503 0536-01 Kahilipali Tun Kau Agri Co TUN 2250 IND 192280503 0436-01 Kapuna Tunnel Kau Agri Co TUN 1900 IRR80503 1232-01 Kaumaikeohu Tun Kawaihae Ranch TUN 2750 IND 192980503 1332-01 Kaumaikeohu Tun Kau Agri Co TUN 2900 IRR 192980503 1729-01 Makakupu Tun 1 Kau Agri Co TUN 3600 IRR 9-7-001:00180503 1729-02 Makakupu Tun 2 Kau Agri Co TUN 3700 IRR 1929 9-7-001:001Hawaii CountyWater Use and Development Plan UpdatePage B-8
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80503 0933-01 Makanau Tun 1 Kawaihae Ranch TUN 1750 IND80503 0833-01 Makanau Tun 2 Kau Sugar TUN 1500 9-5-018:00180503 1730-01 Makua Rch Tun Kau Agri Co TUN 4300 IRR80503 1333-01 Moaula Gluch Tun Kau Agri Co TUN 3500 IRR80503 1333-02 Moaula Trib Tun Kau Agri Co TUN 3100 IRR80503 1530-02 Mudflow 3 Tunnel Kau Agri Co TUN 3500 IRR80503 1630-08 Mudflow Tun 2 Kau Agri Co TUN 3500 IRR80503 1530-03 Mudflow Tunnel Kau Agri Co TUN 3400 IRR80503 0335-01 Naalehu 1 Hawaii DWS PER 12 748 896 MUN 1971 71 10 11 9-5-022:0074400.04 0.2080503 0936-01 New Mtnhouse Tun Hawaii DWS TUN 3400 MUN 1925 46 15 9-7-001:001 45080503 1033-01 Ninole Kau Agri Co ROT 1 2000 877 IRR 196980503 0831-02 Ninole A Kau Agri Co PER 18 128 172MUN1969 5.7 130 183 9-5-019:011 150080503 0831-03 Ninole B Kau Agri Co PER 18 128 172MUN1971 4.87 147 9-5-019:01180503 0831-01 Ninole Gu TH-1 Hawaiiana Inv ROT 3 123 174 OBS 1968 68 4 114 174 9-5-019:01180503 1033-02 Ninole-Wailau 1 Kau Agri Co ROT 3 1792 859 IRR 196880503 1032-01 Ninole-Wailau 3 Kau Agri Co ROT 1 1280 941 IRR 196980503 1630-05 Noguchi 1 Tunnel ML Mac Orchards L.P. TUN 3400 IRR 9-7-001:00180503 1630-10 Noguchi 2 Tunnel ML Mac Orchards L.P. TUN 3450 2480 IRR 1930 9-7-001:00180503 1630-09 Noguchi Mauka Tu ML Mac Orchards L.P. TUN 3600 IRR 1922 9-7-001:00180503 0836-01 Old Mtnhouse Tun Kau Agri Co TUN 3070 IRR 192880503 1229-01 Pahala Hawaii Dws ROT 10 1112 938 MUN 1974 76 383.6 7 9-6-005:0483800.03 0.1180503 1129-01 Pahala 2 Brewer Orchard PER 18 671 820 IRR 1974 75 14 15080503 1229-02 Pahala Deep 2 Hawaii Dws 1112 260 SLD 03 9-6-005:048 080503 1128-01 Pahala Shaft ML Mac Orchards L.P. SHF 774 547 IND 1947 72 22880503 1630-06 Piikea Gul Tun 1 Kau Agri Co TUN 4150 IRR80503 1630-07 Piikea Gul Tun 2 Kau Agri Co TUN 3900 IRR80503 1136-01 Plant N Spr Tun Kau Agri Co TUN 3650 IRR 1928805030830-01 Punaluu Hawaiiana Inv 10 22 20 SLD 1972 73 21280503 1333-04 Shirakura Tunnel Kau Agri Co TUN 3700 IRR 192980503 0436-02 Tanaka Tunnel Kau Agri Co TUN 2100 IRR 192380503 1035-01 Vischer Tunnel Kau Agri Co TUN 2150 IRR80503 0437-01 Waiohinu Expl U S G S ROT 4 1299 972 OBS 1994 94 1014 9-5-005:00280503 1630-01 Weda 1 Tunnel Kau Agri Co TUN 3700 IRR80503 1730-02 Weda 2 Tun 1 Kau Agri Co TUN 3750 IRR80503 1630-02 Weda 2 Tunnel Kau Agri Co TUN 3600 IRR80503 1629-01 Weda 3 Tunnel Kau Agri Co TUN 3400 IRRTotal - Naalehu Aquifer System [80503]0.07 0.31KA LAE AQUIFER SYSTEM [80504]80504 8836-01 Kaalualu TH 1 Kawaihae Ranch ROT 2 40 IND 1966 70080504 8837-01 Kaalualu TH 2 Kawaihae Ranch ROT 2 40 IND 1966 70080504 0240-01 Kau Citrus 1 Bassan M ROT 10 1690 1690 UNU 00 239.9 6 9-3-004:02780504 0139-01 Kau Expl. State Dowrm PER 14 1259 1325 UNU 1990 90 7.2 9-3-003:01480504 8540-01 South Point U S Army ROT 6 51 64 UNU 1941 46 600Hawaii CountyWater Use and Development Plan UpdatePage B-9
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80504 0339-01 South Point Tank U S G S ROT 4 1944 1946 OBS 1997 97 436.1 9-3-004:024Total - Ka Lae Aquifer System [80504]0.00 0.00MANUKA AQUIFER SYSTEM [80601]80601 0247-01 FMT 1 Thibedeau F M 612 612 DOM 92 7.85 9-2-192:042 2080601 0246-01 Kahuku Hawaii Kau Rch PER 8 1037 1095 UNU 87 9.5 300 9-2-001:07280601 0953-01 Okoe Mac Farms Haw PER 12 848 880 IRR 1980 84 3.8 700 3-7-012:002 800 0.16 0.5180601 8741-01 Pali O Kulani TH ROT 2 1967 2Total - Manuka Aquifer System [80601]0.16 0.51KAAPUNA AQUIFER SYSTEM [80602]80602 1953-01 Kaohe 2 S Kona Magoon Estate ROT 8 206 226 DOM 1965 65 1530 2300 15080602 2354-01 Kealia-O'Shea O'Shea D Dug 9 13 DOM 1994 94 2640 8-5-005:009 20080602 1154-01 Milolii-Hceoc Hceoc DUG 60 5 SLD 9680602 1652-01 Opihihale Kona Horizons, Ltd ROT 12 1201 1222 IRR 1993 99 2.6 110 8-7-014:006 65 0.01 0.02Total - Kaapuna Aquifer System [80602]0.01 0.02KEALAKEKUA AQUIFER SYSTEM [80603]80603 3155-02 Halekii-DWS Hawaii Dws ROT 20 1747 1747 MUN 1993 97 484.5 8-1-001:028 1400 0.80 0.9380603 3155-03 Hoku 1 1250 Oceanside ROT 14 1155 1196 IRR 2002 03 51.18 15 8-1-004:056 780 0.42 0.5880603 3056-01 Hokukano Irr 1 Oceanside 1250 ROT 14 811 849 IRR 1993 02 4 300 7-9-012:003 600 0.11 0.2180603 3156-01 Hokukano Irr 2 1250 Oceanside ROT 14 751 791 IRR 2000 02 1.29 900 1040 8-1-004:003 600 0.01 0.1280603 3157-01 Hokukano Mon 1 Hokulia PER 2 46 OBS 2000 00 8-1-004:003 080603 3057-01 Hokukano Mon 2 Hokulia PER 2 106 OBS 2000 00 8-1-004:003 080603 3153-01 Hokukano Ranch Hokukano Ranch Inc. PER 16 2530 1350 DOM 1996 96 1300 7-9-001:001 40080603 3153-02 Hokukano Ranch 2 Hokukano Ranch Inc. PER 13 2875 1675 UNU 2004 04 1316 7-9-001:001 080603 2554-01 Honaunau S Kona Bishop Estate PER 10 193 1956 1140806033255-02 Kainaliu Test State Land ROT 18 1542 1600 UNU 1993 93 306.5 5 7-9-009:01080603 3155-01 Kealakekua Obs. U S G S ROT 4 1741 1505 OBS 1991 91 8-1-001:02880603 2753-03 Keei 4 Hawaii Dws ROT 18 1347 1343 MUN 1992 357.7 10 8-3-011:008 1000 0.74 0.8680603 2753-01 Keei A Hawaii Dws PER 12 744 791 MUN 1958 72 2.75 96 210 8-3-008:0673200.00 0.0180603 2753-02 Keei B Hawaii Dws PER 12 737 774 MUN 1963 72 2.29 99 344 8-3-008:070 375 0.00 0.0280603 2653-01 Keei C Hawaii Dws PER 12 882 913 MUN 1978 85 4.25 22 78 8-3-008:041 500 0.00 0.0380603 2755-01 Napoopoo Thompson W 2 45 40 OTH 1955 7480603 2855-01 Napoopoo Thompson W DUG 72 20 20 OTH 1939 74Total - Kealakekua Aquifer System [80603]2.08 2.76ANAEHOOMALU AQUIFER SYSTEM [80701]80701 5648-03 Aina Lea 1 Bridge Aina Lea LLC PER 15 597 637 UNU 1992 4.4 750 6-8-001:036807015751-02 Cogen Salt 1 Fairmont Orchid Hawaii ROT 18 10 80 OTH 2001 02 6-8-022:008 3500807015751-04 Cogen Salt 2 Fairmont Orchid Hawaii PER 18 12 80 IND 2004 04 6-8-022:008 saltwater80701 5650-02 Culvert Mauna Lani Res ROT 12 124 160 IRR 1991 92 875 6-8-001:052 350 0.25 0.3380701 5650-01 Entrance Mauna Lani Res ROT 8 137 180 IRR 1991 92 2 910 6-8-001:052 250 0.04 0.1880701 5850-01 Fabyonic # 1 Fabyonic Properties LLC DUG 6 7 17 UNU 2001 01 2 1500 6-9-002:023 0Hawaii CountyWater Use and Development Plan UpdatePage B-10
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80701 5452-02 Fifty-One Ft STP Waikoloa Util DUG 72 51 53 IRR 1980 80 900 6-8-001:029 350 0.38 0.4180701 5750-03 Fire Station Mauna Lani Res PER 12 60 70 IRR 1988 88 1.3 6-8-001:052 425 0.44 0.6180701 5651-01 Highway Mauna Lani Res PER 12 121 130 IRR 1988 92 2 6-8-001:052 425 0.48 0.56807014959-04 Hualalai Salt 4 Hualalai Dev ROT 12 5 40 OTH 1995 96 900 7-2-003:004 110080701 5651-02 Mauna Lani SW 1 Mauna Lani Res PER 18 45 310 OTH 1991 91 1.8 6-8-001:052 300080701 5651-03 Mauna Lani SW 2 Mauna Lani Res PER 18 28 188 OTH 1991 1.5 6-8-001:05280701 5452-01 Nursery Waikoloa Util DUG 40 40 IRR 1980 80 920 6-8-001:032 900 0.43 0.7180701 5548-01 Parker 1 Waikoloa Water PER 10 813 865 IRR 1968 72 6.1 600 6-8-002:027 450 0.45 0.6180701 5648-01 Parker 2 TH Waikoloa Water ROT 3 620 651 UNU 1968 72 5.1 6-8-002:02780701 5553-01 Parker 6 Waikoloa Util UNU80701 4532-01 Pohakuloa TH State Dowald ROT 5 6375 1001 UNU 1965 6580701 5750-01 Puako 4 Parker Ranch TUN 37 36 IRR 64 2.8 590 0.83 1.7180701 5750-02 Puako 6 Parker Ranch DUG 66 51 55 UNU 64 3 57080701 5347-01 Puu Anahulu State Land ROT 1517 1548 UNU 94 7-1-003:00180701 5452-03 Resort 1 Waikoloa Util PER 12 51 62 IRR 1988 88 1 720 6-8-001:005 350 0.34 0.5380701 5552-01 Resort Irr 2 Waikoloa Util PER 12 81 91 IRR 1988 90 720 6-8-001:005 700 0.56 0.7580701 5750-04 Stp Mauna Lani ResOTH90 0.35 0.4680701 5551-01 Waikoloa Irr 3 Waikoloa Util PER 12 92 110 IRR 1990 90 2 585 6-8-001:005 500 0.50 0.7480701 5553-02 Waikoloa Saltwtr Waikoloa Util PER 12 30 160 OTH 1990 90 0.2 18000 6-9-007:023 35080701 5553-03 Waikoloa SW Hilton Waikoloa PER 16 24 170 OTH 1997 98 17280 6-9-007:014 3000Total - Anaehoomalu Aquifer System [80701]5.05 7.60PAHOA AQUIFER SYSTEM [80801]80801 Bartlett Bartlett M DOM 2005 05 1-5-062:08680801 3587-05 Bazin Bazin B PER 6 95 DOM 2002 02 38 1-5-028:144 080801 3487-01 Bloemen Bloemen R H V PER 6 110 IRR 2004 04 1-5-026:164 3080801 Camp Camp R & T DOM 2005 05 1-5-054:01880801 3787-02 Chesnut Chesnut J A ROT 5 78 85 DOM 1997 97 7 70 1-5-053:029 2580801 Connie St. Laurence P DOM 2005 05 1-5-059:05780801 3389-02 Diamond Diamond R & L ROT 6 411 426 UNU 2002 02 11.58 20 1-5-017:012 0 0.00 0.0080801 Fenn Fenn I J DOM 2005 05 1-5-055:12980801 Gapp Gapp J DOM 2005 05 1-5-060:07680801 3486-01 Golden Glattauer Lawrence PER 6 130 UNU 2004 04 1-5-027:158 080801Hale O Kai Taylor B UNU 2004 04 1-5-057:08880801 3588-01 Hawn Paradise 1 Watamull Inv PER 12 145 168 UNU 1981 89 8.08 40 1-5-047:17380801 3185-01 Hawn Shores 1 Hwn Sh Comm 8 402 446MUN1964 10.6 18 165000.82 0.8880801 3185-02 Hawn Shores 2 Hwn Sh Comm ROT 10 380 430MUN1971 28 500 0.13 0.1480801 3587-03 Hwn Par Pk-Olmst Olmstead M G ROT 4 107 DOM 1995 95 1-5-049:078 3080801 3081-01 Kapoho Airstrip Hawaii Dws PER 8 287 337 UNU 1961 73 3.2 331 1-4-002:04580801 3589-01 Keaau-Hay Hay G & D ROT 4 195 200 IRR 1995 95 60 1-5-037:005 6080801 3687-03 Keaau-May May J D ROT 6 57 70 DOM 2000 00 1.54 250 1-5-056:099 20 0.00 0.0080801 3389-01 Keaau-Pahoa Rd Hawaii Dws PER 8 427 475 UNU 1960 19 6 12 1-6-009:32180801 2987-01 Keonepoko Iki Hawaii DWS ROT 16 711 740 UNU 2000 00 16.46 10 1-5-008:00680801 3188-01 Keonepoko Nui 1 Hawaii Dws PER 14 603 650 MUN 1977 77 15.11 0 7 1-5-008:001 680 0.00 0.00Hawaii CountyWater Use and Development Plan UpdatePage B-11
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80801 3188-02 Keonepoko Nui 2 State DHHL ROT 16 604 650 MUN 1997 99 16.77 10 1-5-008:001 730 0.45 0.5580801 Love Love D DOM 2005 05 1-5-052:09880801 3487-02 Luawai St. Laurence P ROT 6 135 DOM 2005 05 1-5-026:226 080801 3585-01 Makuu I Intercontl Dev ROT 8 20 30 OTH 1991 92 4.5 315 1-5-010:033 20080801 3585-02 Makuu II Intercontl Dev PER 8 10 256 OTH 1992 92 1-5-010:033 20080801 3686-01 McDonald McDonald J ROT 5 47 IRR 1997 97 325 1-5-056:001 13808013687-06 Monica 1 O' Sullivan J ROT 6 41 DOM 2003 04 234 1-5-057:024 080801 3206-01 Mt View TH 8 ROT 1565 150 UNU 193680801 Noni Kai Fix P UNU 2004 04 1-5-054:04980801 2986-01 Pahoa Battery 2A Hawaii Dws PER 8 711 755 MUN 1960 72 17.8 6 1-5-003:040 200 0.03 0.1080801 2986-02 Pahoa Battery 2B Hawaii Dws PER 705 754 MUN 1960 72 17.8 27 1-5-003:040 380 0.07 0.1980801 3787-01 Pryor Pryor J ROT 5 76 85 IRR 1997 97 6.4 70 1-5-053:049 2580801 3081-02 Puna Therml TH 4 Haw Therml Pwr PER 14 250 290 UNU 196180801 3489-01 Rozett Rozett Nursery PER 6 275 273 IRR 1999 99 14.29 21 1-5-025:081 5080801 3586-03 Shea Shea R ROT 6 34 42 DOM 2002 03 3 140 1-5-056:035 1580801 3485-02 Silverstein Silverstein R 6 79 IRR 1995 95 1-5-010:022 1080801 3688-03 Travis Travis J ROT 6 92 100 UNU 2002 02 4 60 1-5-053:118 080801 3500-01 Wai Pahoehoe Hawaii Dws PER 12 311 361 UNU 1961 16.18 6 1-6-004:04880801 3688-04 Watson Watson R ROT 6 103 108 DOM 2002 03 5.18 1-5-052:073 1280801 Webb Webb C DOM 2005 05 1-5-052:193Total - Pahoa Aquifer System [80801]1.50 1.86KALAPANA AQUIFER SYSTEM [80802]80802 2685-01 Ashida No. Geo Barnwell Gedco ROT 802 8300 UNU 1980 87 8 46080802 2883-01 Hgp-A Geo Nat Energy Lab ROT 600 6455 OTH 1976 8780802 3080-01 Kapoho Crater Hawaii Dws DUG 66 38 46 UNU 1965 72 3.2 64 190 1-4-091:01180802 2983-01 Kapoho PGV MW1 Puna Geo Ventr ROT 10 610 720 OTH 1990 91 8 20 25080802 2983-02 Kapoho PGV MW3 Puna Geo Ventr ROT 13 610 720 OTH 1991 91 16 18 125080802 2883-03 Kapoho St 1 Geo Puna Geo Ventr ROT 619 7290 OTH 1981 87 11.3 120080802 2883-04 Kapoho St 2 Puna Geo Ventr ROT 718 8605 OTH 1982 8780802 2883-06 Kapoho St. 1-A Puna Geo Ventr ROT 1985 11 109880802 2487-01 Keauohana 1 Hawaii Dws PER 8 752 802 MUN 1961 76 2.94 72 1-2-009:0392000.02 0.0680802 2487-02 Keauohana 2 Hawaii Dws PER 12 753 803 MUN 1970 72 3.1 124 124 1-2-009:0393400.03 0.0580802 2883-02 Lanipuna 1 Geo Barnwell Geo ROT 600 8389 OTH 1981 8780802 2883-05 Lanipuna 6 Geo Barnwell Geo ROT 600 4956 OTH 1984 8780802 2783-01 Malama Ki State Dowald PER 8 274 319 UNU 1962 73 0.9 5530 660080802 2881-01 Pohoiki Puna Oneloa Co Inc ROT 4 132 140 OTH 1973 88 5 722 2300 1-4-002:06980802 2102-01 Pulama State Dowald PER 8 230 250 UNU 1963 73 3.3 278 270 1-1-001:00980802 2883-07 Puna Geo MW2 Puna Geo Ventr ROT 4 588 640 OBS 1991 91 18.7 37080802 2686-01 Puna Therml TH 1 Haw Therml Pwr PER 14 1009 217 UNU 1961 7380802 2686-02 Puna Therml TH 2 Haw Therml Pwr PER 14 1035 558 UNU 1961 7380802 2982-01 Puna Therml TH 3 Haw Therml Pwr PER 18 563 690 UNU 196180802 2979-02 Vacationland #1 Harms A B ROT 6 6 13 SLD 2000 01 250 1-4-070:028 080802 2979-03 Vacationland #2 Harms A B ROT 6 11 19 SLD 2000 01 250 1-4-070:027 0Hawaii CountyWater Use and Development Plan UpdatePage B-12
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80802 2979-04 Vacationland #3 Harms A B ROT 6 12 19 SLD 2000 01 250 1-4-070:015 080802 2979-05 Vacationland #4 Harms A B ROT 6 12 25 SLD 2000 01 250 1-4-070:028 080802 2979-06 Vacationland 1A Harms A B ROT 6 7 12 DOM 2002 0.56 1-4-067:039 1280802 2979-07 Vacationland 2A Harms A B ROT 6 12 15 DOM 2002 02 1.5 1-4-070:027 12808022979-08 Vacationland 3A Harms A B ROT 6 12 15 DOM 2002 02 0.9 1-4-070:015 1280802 2979-09 Vacationland 4A Harms A B ROT 6 12 15 DOM 2002 02 1.13 1-4-070:028 12Total - Kalapana Aquifer System [80802]0.05 0.11HILINA AQUIFER SYSTEM [80803]80803 2317-01 Haw Vol Nat Pk Haw Vol Nat Pk ROT 14 3606 4127 OBS 1973 73 1806Total - Hilina Aquifer System [80803]0.00 0.00KEAIWA AQUIFER SYSTEM [80804]80804 1128-02 Palima ML Mac Orchards L.P. PER 18 304 375 IRR 1970 8.7 9 1280804 0830-02 Punaluu TH-2 Kau Agri Co ROT 3 56 90 IRR 1968 240 240Total - Keaiwa Aquifer System [80804]0.00 0.00KEAUHOU AQUIFER SYSTEM [80901]80901 4461-01 Cooper Cooper M B 4 185 UNU 1985 90 2300 7-3-049:00580901 3957-04 Doutor Coffee #1 Doutor Coffee Co. ROT 12 1445 1462 IRR 2001 01 43.03 10 3-7-011:023 23080901 4463-04 Dust Control Cyanotech Corp 22 OTH 1987 8780901 3657-01 Holualoa Hawaii Dws ROT 14 1123 1172 MUN 1983 84 5.64 18 7-6-006:018 500 0.57 0.7180901 4060-01 Honokohau Quarry Honokohau Prop ROT 6 121 137 OTH 1995 95 2 500 7-4-028:026 2580901 4158-02 Honokohau-DWS Hawaii Dws ROT 20 1681 1735 MUN 1991 98 109.5 8 7-4-006:00612001.60 1.9380901 4258-03 Hualalai Expl Hawaii Dws ROT 18 1683 1822 MUN 1993 98 292.9 5 7-3-006:00312000.96 1.4280901 4559-01 Huehue Ranch 1 Huehue Ranch PER 10 1579 1690 MUN 1985 88 7.8 60 7-2-006:009 350 0.20 0.2780901 4459-01 Huehue Ranch 2 Huehue Ranch ROT 14 1534 1642 MUN 1991 03 7.3 151 7-2-006:009 570 0.28 0.4180901 4459-02 Huehue Ranch 4 Huehue Ranch ROT 14 1533 1625 MUN 1992 92 7 110 7-2-006:0094900.00 0.0080901 3557-01 Kahaluu A Hawaii Dws ROT 12 833 878 MUN 1959 74 4.34 40 97 7-8-009:054 700 0.89 1.0380901 3557-02 Kahaluu B Hawaii Dws ROT 12 839 881 MUN 1959 74 3.2 13 230 7-8-009:067 700 0.01 0.0380901 3557-03 Kahaluu C Hawaii Dws ROT 12 834 868 MUN 1969 70 4.66 8 78 7-8-009:077 700 0.56 0.8180901 3557-04 Kahaluu D Hawaii Dws ROT 14 855 905 MUN 1970 74 4 8 112 7-8-009:0767200.96 1.0980901 3457-04 Kahaluu Deep Monitor State Cwrm PER 8 308 738 OBS 2000 00 1.86 7-8-010:028 080901 3557-05 Kahaluu Shaft Hawaii Dws SHF 156 590 595 MUN 1976 77 4 34 344 7-8-010:054 4200 3.53 4.4280901 4061-01 Kaho Obs 3 Natl Park Serv ROT 2 37 52 OBS 1996 96 2.5 7-4-008:01080901 4161-01 Kaho Obs. 1 Natl Park Serv ROT 2 23 34 OBS 1996 96 0.5 7-4-008:01080901 4161-02 Kaho Obs. 2 Natl Park Serv ROT 2 55 69 OBS 1996 96 2.7 7-4-008:01080901 3758-01 Kailua Kona Hawaii Dws PER 6 595 615 UNU 1944 49 3.32 463 600 7-5-017:01180901 3255-01 Kainalu Obs. U S G S ROT 1693 1543 OBS 1991 91 420 18 7-9-008:00380901 4358-01 Kalaoa A Hawaii Dws ROT 14 1799 1850 MUN 1990 91 237.9 10 12 7-3-004:005 300 0.00 0.0680901 3858-01 Kalaoa Keopu Deep State Cwrm ROT 8 736 1310 OBS 2001 01 7-5-010:016 080901 4360-01 Kalaoa N Kona State Dowald ROT 10 680 702 UNU 1968 72 3.2 600 7-3-010:03380901 4160-01 Kaloko Irr 1 Tokyo Grn Haw PER 12 565 584 UNU 1985 92 2.5 940 7-3-009:01780901 4160-02 Kaloko Irr 2 Tokyo Grn Haw PER 12 542 561 UNU 1985 92 1.5 955 7-3-009:017Hawaii CountyWater Use and Development Plan UpdatePage B-13
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80901 3759-01 Kaneyoshi Irr Kaneyoshi Co Ltd ROT 5 37 47 IRR 1999 99 0.8 5000 7-5-020:024 7580901 4461-02 Keahole Helco HELCO PER 12 208 253 IND 1993 04 1 5900 7-3-010:002 500 0.07 0.1480901 4462-05 Keahole MW-11 State Dot-Airp ROT 2 140 172 OBS 1996 96 1.4 7-3-043:00380901 4462-06 Keahole MW-13A State Dot-Airp ROT 2 55 83 OBS 96 2.4 7-3-043:00380901 4462-07 Keahole MW-13B State Dot-Airp ROT 2 55 64 OBS 96 2.4 7-3-043:00380901 4463-01 Keahole MW-14A State Dot-Airp ROT 2 21 50 OBS 96 2.6 7-3-043:00380901 4463-02 Keahole MW-14B State Dot-Airp ROT 2 21 40 OBS 96 2.6 7-3-043:00380901 4463-03 Keahole MW-14C State Dot-Airp ROT 2 21 30 OBS 1996 96 2.6 7-3-043:00380901 4363-01 Keahole Point 1 Uwajima Fisheries ROT 4 15 32 OTH 1989 89 1 15000 7-3-043:003 25080901 4363-10 Keahole Point 10 Uwajima Fisheries ROT 4 15 32 OTH 1989 89 1 15000 7-3-043:003 25080901 4363-11 Keahole Point 11 Uwajima Fisheries ROT 4 50 OTH 7-3-043:00380901 4363-12 Keahole Point 12 Uwajima Fisheries ROT 4 50 OTH 7-3-043:00380901 4363-02 Keahole Point 2 Uwajima Fisheries ROT 4 15 32 OTH 1989 89 1 15000 7-3-043:003 25080901 4363-03 Keahole Point 3 Uwajima Fisheries ROT 4 15 32 OTH 1989 89 1 15000 7-3-043:003 25080901 4363-04 Keahole Point 4 Uwajima Fisheries ROT 4 15 32 OTH 1989 90 1 15000 7-3-043:003 25080901 4363-05 Keahole Point 5 Uwajima Fisheries ROT 4 15 32 OTH 1989 90 1 15000 7-3-043:003 25080901 4363-06 Keahole Point 6 Uwajima Fisheries ROT 4 15 32 OTH 1989 90 1 15000 7-3-043:003 25080901 4363-07 Keahole Point 7 Uwajima Fisheries ROT 4 15 32 UNU 1989 89 1 15000 7-3-043:00380901 4363-08 Keahole Point 8 Uwajima Fisheries ROT 4 15 32 OTH 1989 89 1 15000 7-3-043:003 25080901 4363-09 Keahole Point 9 Uwajima Fisheries ROT 4 15 32 OTH 1989 89 1 15000 7-3-043:003 25080901 4462-02 Keahole-DOT State Dot-Airp PER 8 134 165 OTH 1992 93 1.5 382580901 4057-01 Keahuola QLT 1 Hawaii Dws ROT 16 1765 1787 MUN 1994 96 187.8 10 7-4-002:0069601.09 1.4080901 3457-01 Keauhou 1 Bishop Estate PER 10 175 193 IRR 1956 92 7-8-010:002 450 0.09 0.2080901 3357-01 Keauhou 2 Bishop Estate ROT 10 385 430 UNU 1966 97 0.00 0.0080901 3457-02 Keauhou A Hawaii Dws PER 16 723 765 UNU 1985 87 2.9 7-8-010:05080901 3456-01 Keauhou B Kam Inv Corp PER 14 1018 1047 UNU 1989 89 3.5 7-8-010:00680901 3457-03 Keauhou Irr 3 Otaka Inc PER 12 366 387 IRR 1985 7-8-010:077 500 0.14 0.2880901 3355-01 Keauhou-Kam 2 Kam Inv Corp Rot 18 1618 1585 UNU 1991 91 278.1 5 7-8-004:01580901 3355-02 Keauhou-Kam 3 Kam Inv Corp ROT 18 1658 1658 UNU 1992 92 386 5 7-8-004:07580901 3355-03 Keauhou-Kam 4 Kam Inv Corp ROT 18 1650 1650 UNU 1994 94 228 6 7-8-002:00180901 3357-04 Keauhou-Kona C C Otaka Inc PER 12 397 415 IRR 1990 90 2 7-8-010:051 470 0.15 0.2780901 3957-01 Keopu-Puuhonua Haseko-Hawaii ROT 14 1675 1706 UNU 1993 93 47 10 7-5-001:00180901 4458-01 Kohanaiki 1 Nansay Hawaii ROT 14 1799 1952 UNU 1991 91 9.9 35 7-2-005:00180901 4458-02 Kohanaiki 2 Nansay Hawaii ROT 18 1800 1880 UNU 1991 91 10.2 15 7-2-005:00180901 3957-02 Komo Monitor U S G S ROT 4 1601 1623 OBS 1991 91 7-5-001:05580901 3859-01 McCaskill Mc Caskill J UNU 1942 89 7-5-018:019 080901 4363-13 Net Washing Cyanotech Corp ROT 36 26 OTH 1987 87 7-3-043:042 8080901 3657-02 Pahoehoe Hawaii Dws PER 16 1146 1180 UNU 1990 92 4.28 400 7-7-006:01880901 4059-01 Palani State Dowald PER 12 800 853 SLD 1958 72 1.6 2800 430080901 3857-04 Waiaha-DWS Hawaii DWS ROT 20 1542 1752 UNU 2000 00 59.56 10 7-5-015:01580901 3857-01 Waiaha-DWS Hawaii Dws ROT 20 1602 SLD 00 7-5-014:016Total - Keauhou Aquifer System [80901]11.10 14.47KIHOLO AQUIFER SYSTEM [80902]Hawaii CountyWater Use and Development Plan UpdatePage B-14
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80902 4959-05 Beach Pool Hualalai Dev PER 6 3 8 OTH 1996 96 0.3 7-2-003:005 15080902 4950-01 Big Island C C 1 Big Isle C C ROT 16 2105 2181 IRR 1992 95 8 43 7-1-005:02670080902 4950-02 Big Island C C 2 Big Isle C C ROT 16 2130 2208 IRR 1995 96 11.41 7-1-005:041 70080902 4959-08 Fitness Center Hualalai Dev ROT 6 13 26 OTH 1996 96 7-2-003:005 10080902 4859-01 Hualalai Makai Hualalai Dev ROT 10 250 270 UNU 1994 94 1.6 7-2-003:00680902 4959-01 Hualalai Salt 1 Hualalai Dev ROT 12 3 40 OTH 1995 96 2400 7-2-003:004 110080902 4959-02 Hualalai Salt 2 Hualalai Dev ROT 12 3 40 OTH 1995 96 2500 7-2-003:004 110080902 4959-03 Hualalai Salt 3 Hualalai Dev ROT 12 4 80 OTH 1995 96 2800 7-2-003:004 110080902 4558-01 Huehue Ranch 3 Huehue Ranch PER 14 1519 1598 MUN 1991 91 7 7-2-004:007 570 0.24 0.5280902 4558-02 Huehue Ranch 5 Huehue Ranch ROT 14 1529 1600 MUN 1992 92 22.5 35 7-2-004:014 570 0.01 0.0280902 4856-01 Kaupulehu Hualalai Develoment ROT 12 934 985 IRR 2001 01 5.39 250 7-2-003:003 590 0.60 0.8180902 4757-01 Kaupulehu Irr 1 Kaupulehu Land Co. PER 12 848 975 IRR 1991 94 2.8 250 7-2-003:003 350 0.11 0.3080902 4757-02 Kaupulehu Irr 2 Kaupulehu Land Co. PER 12 868 980 IRR 1990 95 6 7-2-003:003 550 0.52 0.7680902 4757-03 Kaupulehu Irr 3 Kekaha Venture ROT 12 888 1000 IRR 2001 02 3.91 220 7-2-003:003 55080902 4757-04 Kaupulehu Irr 4 Kekaha Venture ROT 12 915 1013 IRR 2002 02 2.56 240 7-2-003:003 55080902 4658-01 Kaupulehu Pot 1 Kaupulehu Wtr ROT 12 1343 1440 MUN 1981 96 6.9 38 7-2-003:003 450 0.33 0.5380902 4658-02 Kaupulehu Pot 2 Kaupulehu Wtr ROT 12 1343 1444 MUN 1986 95 7 7-2-003:003 450 0.25 0.3680902 4657-01 Kaupulehu Pot 3 Hualalai Dev ROT 16 1321 1421 MUN 1999 99 5.8 110 7-2-003:0034500.30 0.5680902 4657-02 Kaupulehu Pot 4 Kaupulehu Makai ROT 16 1345 1454 MUN 2002 02 4.81 190 7-2-003:003 450 0.45 0.6680902 4657-03 Kaupulehu Pot 5 Kaupulehu Makai ROT 16 1335 1416 UNU 2004 04 5.16 90 7-2-003:003 080902 4759-01 KI-1 Wb Kukio Llb PER 14 591 610IRR1990 01 1.6 590 7-2-004:0165000.31 0.3380902 4759-02 KI-2 Wb Kukio Llb PER 12 551 570IRR1991 00 1.2 460 7-2-004:016 500 0.38 0.4080902 4759-03 KI-3 Wb Kukio Llb PER 16 592 618IRR1992 01 0 720 7-2-004:0165000.32 0.3680902 4953-01 Kiholo State Dowald ROT 12 932 971 UNU 1972 73 2.6 340 7-1-002:00180902 4858-01 Kona Village 1 Pia-Kona Ltd ROT 4 501 528 UNU 1960 74 0.8 385 410 7-2-003:00380902 4858-02 Kona Village 2 Kona Vil Assoc ROT 8 503 523IRR1968 72 1.8 593 7-2-003:003 232 0.01 0.0880902 4858-03 Kona Village 3 Kona Vil Assoc ROT 10 500 534IRR1973 73 2.8 300 830 7-2-003:003 174 0.09 0.1780902 4859-03 Kukio Lagoon 1 WB Kukio Resorts DUG 72 7 12 OTH 2002 03 0.94 7-2-016:002 150080902 4959-19 Kukio Lagoon 2 WB Kukio Resorts DUG 72 8 12 OTH 2002 03 0.94 7-2-016:003 150080902 4960-04 Kukio Obs A Huehue Ranch DUG 2 3 10 OBS 1991 91 0.5 7-2-004:005 080902 4960-03 Kukio Obs B Huehue Ranch DUG 2 3 15 OBS 1991 91 0.11 7-2-004:005 080902 4959-10 Kukio Obs C WB Kukio Resort ROT 2 9 20 OBS 2001 01 0.25 7-2-004:005 080902 4959-13 Kukio Obs C Huehue Ranch DUG 2 9 20 SLD 1991 01 0.25 7-2-004:005 080902 4960-01 Kukio Obs D WB Kukio Resort ROT 2 8 18 OBS 2001 01 0.25 7-2-004:005 080902 4959-16 Kukio Obs D Huehue Ranch DUG 2 7 18 SLD 1991 01 0.47 7-2-004:005 080902 4959-11 Kukio Obs E WB Kukio Resort ROT 2 8 20 OBS 2001 01 0.25 7-2-004:005 080902 4959-14 Kukio Obs E Huehue Ranch DUG 2 9 20 SLD 1991 01 0.53 7-2-004:005 080902 4959-12 Kukio Obs F WB Kukio Resort ROT 2 7 17 OBS 2001 0.5 7-2-004:005 080902 4959-15 Kukio Obs F Huehue Ranch DUG 2 7 15 SLD 1991 01 0.53 7-2-004:005 080902 4959-06 Main Pool Hualalai Dev PER 6 4 11 OTH 1996 96 1 7-2-003:005 9080902 4760-01 Maniniowali 1 Maniniowali Equity Co., ROT 12 281 UNU 2002 02 7-2-004:018 080902 4959-07 Palm Grove Hualalai Dev PER 6 3 9 OTH 1996 96 1.1 7-2-003:004 6080902 4850-01 Puu Lani Puuwaawaa Rch ROT 10 2314 6800MUN1978 92 18.8 60 7-1-006:019 72 0.02 0.0380902 4650-01 Puu Waawaa Puuwaawaa Rch ROT 7 2550 5595MUN1978 92 231.6 45 7-1-001:002 74 0.02 0.06Hawaii CountyWater Use and Development Plan UpdatePage B-15
Appendix B: CWRM Island of Hawaii Well Database (as of October 2005)Aquifer System Well No. Well Name Owner User TypeCasing Dia.Ground Elev.Well DepthUse Cat.Yr. Drill.Use Yr.Init. HeadInit. Chl.Max. Chl. TMKPump CapacityAverage PumpageHigh Avg. Pumpagein. ft. ft. ft. ppm ppm gpm mgd mgd80902 4959-20 Raptor Residence Raptor Residence LLC PER 8 5 65 UNU 2003 03 1.5 17119 7-2-017:001 080902 4959-09 Ryan Salt Hitherandthirthering ROT 4 60 OTH 1999 7-2-011:008 080902 5352-01 West Haw Landfil Waste Mgmt Haw ROT 8 192 220IRR1993 94 2 910 7-1-003:001 100 0.30 2.33Total - Kiholo Aquifer System [80902]4.26 8.28TOTAL - ISLAND93.94 131.97Hawaii CountyWater Use and Development Plan UpdatePage B-16
APPENDIX C
Description of the
County of Hawaii
Department of Water Supply
APPENDIX C: Description of the County of Hawaii Department of Water Supply
Page C-1
Hawaii County
Water Use and Development Plan Update
-Ka Wai A Kane!
Water…Our most Precious Resource!
The County of Hawai'i Department of Water Supply
“The Department of Water Supply does not sell water; water is free – the department sells
service…the charges collected by the Department of Water Supply are to cover the cost of
pumping, treating, storing, and delivering potable water.”
Water Board
The Department of Water Supply (DWS) is a semi-autonomous agency of the County of
Hawai‘i, which is governed by rules and regulations adopted by a nine-member Water Board.
The board members are selected by the county mayor to represent the nine council districts
around the county. As such, the county council is not involved in the Department of Water
Supply’s budgetary or policy decisions. The Water Board makes policy decisions, approves all
of DWS’ contracts and sets the budget for the Department. While each of the nine council
districts are represented, the Board members do not so much advocate for their own particular
districts as they do work together for the benefit of all DWS customers. The board also hires the
Water Manager who runs the day to day operations of the Department. Currently, the Water
Manager is Milton D. Pavao, P.E.
Function
The primary function of the Department is to deliver safe, clean, good tasting, potable water to
its customers throughout its 24 water systems and 67 sources located around the island. Because
of the immense size of the Big Island and the isolated nature of many of the communities, these
individual water systems are typically not interconnected, except in the more densely populated
districts of South Hilo and Kona. The Department continually strives to provide highly
dependable, excellent quality water at a reasonable cost. The Department is fortunate to have
dedicated water system operators. They routinely have to work late at night, weekends and
Holidays to provide seamless service to DWS customers, and occasionally have to put their jobs
ahead of their personal lives during emergencies and difficult times.
Revenues
The Department operates and maintains its water systems with revenues generated wholly
through the sales of its water service. The DWS does not receive any money from the County’s
General Fund. It does not receive any property taxes or other taxes. DWS is purely customer-
driven and must operate on revenue from the service it provides. In 2008, the Department had
approximately 41,000 accounts serving well over 100,000 residents. Rates are structured such
that monthly rates from customers pay only for normal operations and maintenance. Another
fee, which is known as a facilities charge (FC), is a one-time charge to new customers for the
privilege of connecting to the Department’s water system infrastructure in order to obtain county
water service (where available). Water systems are expensive and the existing infrastructure was
paid for by past and current customers. The FC paid by the new customer is simply a “buy-in” to
the existing water system. Over time, the FC monies help to provide for major capital
improvement projects including new wells, reservoirs and transmission lines. An example of
Appendix C: Description of the County of Hawaii Department of Water Supply
Page C-2
Hawaii County
Water Use and Development Plan Update
such a project is the recent construction of a two-million gallon reservoir and production well in
the Waiaha region in Kona.
Other Funds and Expenditures
For the past 15 plus years, the Department has not received any state appropriations. It has only
received revolving fund loans provided by the U.S. Environmental Protection Agency (USEPA)
via the state Department of Health for certain projects. Those funds are minimal and are used
only to help update and bring the existing water systems into compliance with the USEPA’s
often changing criteria. In 2007, a $25M General Obligation Bond was secured by DWS in
order to complete several critical, major water supply projects, including the Palani Road
Transmission Waterline Project. Already underway, when completed, this $12.3M project will
bring high quality, excellent tasting water from wells located above the Mamalahoa Highway
down into Kailua-Kona. These wells produce very high quality water pumped from perched
aquifers and the new pipeline will allow transmission of this water to large segments of North
Kona, improving water quality for many of DWS’ existing customers. For 2010, DWS is
securing another $30M bond to carry out several more critical source, storage and transmission
projects around the island.
There are many financial challenges associated with providing water service, including fixed
costs and legal mandates that must be covered by DWS revenues. A good part of DWS
operating funds are used to ensure that the water quality provided to our existing customers is in
compliance with EPA standards. These standards are getting stricter over time. DWS spends
more than $600,000.00 a year to test the water to ensure compliance. EPA mandates often
require large expenditures from capital funds for well development and upgrades to existing
water sources.
DWS is Hawaii Electric Light Company’s (HELCO) biggest customer. It may be surprising for
many to learn that 1/3 or more of DWS’ total budget goes to pay HELCO for energy costs. In
2007 that amounted to $16.5 million dollars primarily to pay for the energy to operate the
department’s well and booster pumps around the island. The Water Board has recently approved
a new policy giving the Department the ability to make adjustments every two months to the
power cost portion of the customer billing as needed. This will allow DWS to better track
changes in the energy costs, either up or down, which are administered by HELCO to DWS.
Previously, the power cost adjustment only occurred annually. Power rates have been trending
downward more recently and the power cost portion of customer billing has been reduced to
follow suit.
Subdivisions and System Expansion
County Subdivision code requires that new subdivisions have a water system meeting county
standards. Therefore, most expansion of the county water systems is accomplished by land
owners and developers in conjunction with building their own projects, by adding onto and tying
in to the county’s existing water system infrastructure. When the proposed growth from new a
development exceeds the water availability in a particular area, the developers are also
responsible for adding source, storage, and transmission to provide the water needed for their
own projects and allow them to move forward.
Appendix C: Description of the County of Hawaii Department of Water Supply
Page C-3
Hawaii County
Water Use and Development Plan Update
DWS’ financial structure does not provide funding for significant expansion of its water systems
to reach new customers in non-service areas, including existing subdivisions that were
subdivided previously without water, prior to current subdivision code. Water rates and facilities
charges are structured only to maintain the facilities and service of existing water systems. The
rates do not provide for the high cost of expanding water systems in order to take on limited
numbers of additional customers. It is important to note that because DWS does not receive any
funding from property taxes, anyone not receiving county water is not paying into the county
water system. Only DWS’ customers pay into the water systems. DWS cannot put the financial
burden of extending infrastructure to serve limited numbers of new customers spread out in
scattered areas onto its existing customer base. Not when the cost to expand infrastructure is too
great compared to the return gained by adding those new customers. If DWS did so, the
department could go bankrupt or the water rates charged to existing and new customers would
need to be drastically increased to pay for system expansion. Spending tens of thousands,
hundreds of thousands, or even millions of dollars extending the water systems to pick up
relatively low numbers of additional customers would never be cost effective or fair for our
existing customers. It does not make economic sense. DWS’ greater responsibility is to its
existing customer base. DWS has to keep water costs as low as financially responsible. Instead,
the financial burden of expansion is placed on the applicants wishing to become new customers
and obtain water service from the county. The investment on the part of the land owners is
typically compensated by an increase in the value of their properties because of the availability
of county water. The cost of expanding county water systems needs to be borne by those
benefitting directly from the new service, both in terms of the convenience and increased
property values. Usually, landowners and homeowners who bought property without access to
county water paid a proportionately lower price for their property than landowners and
homeowners whose property has county water. Accordingly, the annual real property tax
assessment of a lot without water also tends to be lower than a lot enhanced by having access to
county water.
Improvement Districts
In the past, DWS has acquired or accepted substandard water systems from others, such as the
old camp systems from the sugar cane days. Many years later, DWS is still in the process of
paying to upgrade some of these systems to meet DWS standards. Nowadays, it is a requirement
that any privately owned water systems wishing to be given over to DWS, must first be brought
up to all DWS standards before the Water Board will accept the dedication of the system.
Another way that the county’s water systems expand is through the efforts of existing
communities using external funding such as low interest loans and the USDA’s Rural
Development Loan Grant program. Using a mechanism known as Improvement Districts (ID’s),
these low interest loans and federal grant funds can be made available to the communities
desiring county water service. DWS encourages and works with those existing subdivision
communities that wish to go through the ID process in order to become new DWS customers.
An example is the Kona Coastview/ Wonderview subdivision. In that case, the Improvement
District process, in combination with the USDA Rural Development Loan Grant Program,
provided the funding to construct an upgraded water system meeting DWS standards to replace
the existing sub-standard water system. By reconstructing a water system and meeting all of the
county’s water system standards, the subdivision’s community was able to turn the system over
Appendix C: Description of the County of Hawaii Department of Water Supply
Page C-4
Hawaii County
Water Use and Development Plan Update
to DWS, who will then operate and maintain the water system in perpetuity and provide service
to the community.
Out-of-Bounds Service
Currently, DWS does have an “Out-of-Bounds” policy, which may allow individual property
owners to obtain county water even though their property does not front a county waterline or
they may not be within a DWS pressure service zone. Where possible, these owners are limited
to just one equivalent unit (EU) of water, which is adequate to serve a single-family residence.
An EU allows a maximum day usage of 600 gallons for any one day. Maximum day usage is
defined as 1.5 times the average day use, therefore one EU allows for an average day usage of
400 gallons.
To obtain an “Out of Bounds” service, the owners must sign a DWS policy agreement
recognizing the customer’s responsibilities in these cases, which may include obtaining legal
easements over neighboring properties to run customer-maintained, private waterlines from the
Department’s water meter to their property. In addition, when the property is partially or
completely outside of the pressure service zone, the owner is also required to execute an
Elevation Agreement stating that the owner understands and accepts that the pressure to the
property may be substandard and recognizes all conditions, limitations, and requirements placed
upon the owner. When serving properties located outside the service pressure zone, the
Department’s water meter itself still needs to be located within the pressure service zone.
These “Out-of-Bounds” policies can lead to what are commonly known as “spaghetti lines”
servicing some neighborhoods. Although there are a number of negative issues associated with
these “spaghetti lines”, this practice accommodates as many members of the community as
possible without imposing extreme financial hardship on them by, instead, imposing greater
responsibility upon the customer.
Land Applications and Water Commitments
New private development projects require water and the Hawaii County Planning Department
works to ensure that water is available when considering approval of any changes in current
zoning. When applications for projects affecting land use are submitted to the County Planning
Department, such as for change of zone, subdivision, boundary amendments, additional farm
dwellings, ohana dwellings, special management areas, etc., DWS is consulted as to whether
water is available to meet the needs of the subject project. Copies of the applications are
submitted to the Water Resources and Planning (WRAPS) branch of the Engineering
Department. Water availability is researched for the subject area and WRAPS provides a letter
to the Planning Department stating whether water is available for the proposed project and what
improvements may be required to make water available. When looking at proposed projects,
DWS often requires water usage demand calculations, which must include average day usage
and peak hour flow rates, provided by the developer’s engineer for DWS review and approval.
Based on those calculations and the water availability policy for the subject area, DWS
determines if it can support a particular project. If the water source, storage and transmission
capabilities of the existing water system are adequate to meet the requirements of the project, the
developer is then responsible for extending the water system infrastructure to serve the project.
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Hawaii County
Water Use and Development Plan Update
This includes, but is not limited to, water lines of sufficient size and capacity to provide adequate
pressure and flow to meet both domestic needs and fire protection.
DWS is not part of the building permit approval process. DWS is not generally consulted for
building projects when there are no required changes to land use or zoning classification. On
rare occasions, this has led to conflict when adequate water has not been available to projects
already approved by the building department but most developers do come in beforehand to
check with DWS to verify water is available before building their project. It is strongly
recommended by the Department that they do so.
When applications are filed and it is determined that adequate water is available, which may or
may not require onsite and offsite water system infrastructure improvements to be constructed at
the expense of the applicant, the Department is able to provide water commitments to the
applicant. Water commitments ensure that the water that is deemed to be available to the project
at the time of the request is reserved and therefore will still be available to the project at the time
of completion. This is important because water availability can change without notice. Water
commitments are not issued unless a water commitment deposit of $150.00 per equivalent unit
(EU) of water is paid to DWS. The commitment expires after three years but DWS, at its
discretion, may extend water commitments a year at a time by an additional payment of $150.00
per EU, so long as tangible progress has been made on the project. Money paid as a deposit for
water commitments and extensions will later be applied toward the customer’s payment of the
prevailing facilities charges at the time service is granted.
Water commitments go with the land and are not sellable, tradable, transferable or otherwise
exchangeable, except upon rare approval by the Water Board and only to adjacent lands served
by the same water system.
Water Availability and Developer Contributions
The Department’s water availability policy varies around the island as different supply sources,
system robustness, demand and potential demand based on zoning type, are encountered. The
Department sets water availability policy based on the existing water system and the projects
currently under construction relative to factors particular to an area or system, per the Rules and
Regulations set forth and adopted by the Water Board:
“If the Department, on the basis of population data, availability of water, existence of
water sources, waterlines or other facilities, engineering requirements, and other related
and relevant data, anticipates that a consumer, developer or subdivider can be provided
with sufficient water for the estimated usage of a proposed new project or development,
meeting the Department’s minimum standards, the Department may commit to the
consumer, developer or subdivider that there is, or it is anticipated that there will be,
sufficient water to service the proposed new project or development. The Department, in
giving such a water commitment, may impose time limits and other conditions for the use
of such commitment upon the consumer, developer or subdivider, as the Department
deems necessary. The Board may establish guidelines and policies for the issuance of
formal written water commitments.”
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Hawaii County
Water Use and Development Plan Update
When DWS responds to a land application sent over by the Planning Department, DWS indicates
in writing whether the affected water system has the capacity to accommodate the project being
proposed. If the project’s water demands fall within the water availability policy for the subject
areas and the system is capable of handling the additional demand, DWS indicates the point of
adequacy within the system and gives a very brief outline of system improvements, if any,
required of the applicant to bring the water service to the subject property. The applicant would
then need to provide the engineered design for any necessary offsite improvements such as
storage, transmission, and distribution infrastructure required for the project. If the system does
not have the capacity to meet the needs of the project, then the developer may need to scale back,
combine adjacent properties, or provide additional source to meet the needs of the project.
In those cases where DWS simply does not have adequate source, storage and or transmission to
satisfy the needs of a proposed development, major developers may enter into an agreement with
DWS whereby the developer promises to provide a new water source, storage reservoirs and
transmission systems. The agreements state the proportional share of the source water going to
the developer and the proportional share going to DWS, which is currently allocated two-thirds
to the developer and one-third to DWS for use by the its customers. As an example, a well
capable of producing 700 gallons per minute (gpm) or one million gallons per day (1.0 MGD)
provides enough water for 1,666 equivalent units of water. For a well this size, the developer’s
share at two-thirds would be 1,111 equivalent units and DWS’ share at one-third would be 555
equivalent units.
When completed, those developer-paid facilities are dedicated to the Water Board. DWS then
operates and maintains the facilities. The developer receives a credit toward the facilities charge
on each equivalent water unit it receives based on standard percentages for each type of facility
constructed by the developer. However, the investment by the developer must meet or exceed
the total of the facilities charge for the equivalent units allocated to the developer in order to
receive the credit. More information about these percentages can be found in the department’s
Rules and Regulations which are posted online at www.hawaiidws.org.
Water for the Future
It is important to take a look at the long term effects of continued development on the island’s
resources, especially water. Some areas of the island have more water than could ever be used
by even the full build-out of potential development based on land classification and zoning.
Other areas may have more limited ability to meet future demands. However, it is not a runaway
train as far as potential overuse of the islands aquifers. Developers will always have to prove
that they have source available before they are allowed to construct their projects. They not only
have to commit to developing source wells, storage and transmission, they also have to prove
that the water is actually accessible to their projects. In a practical sense, finding suitable
locations to tap into the aquifers and still be able to serve specific project locations is typically a
much greater limiting factor than the official safe yield of the underlying aquifers.
More information about the Department of Water Supply can be found at the DWS website at
www.hawaiidws.org.
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Water Use and Development Plan Update
DISCLAIMER: All statements and ideas herein are believed to be reliable, truthful and accurate
to the best of DWS’ knowledge at the time of this writing. They are not guaranteed in any way
by anybody and are subject to change over time. The Water Board and DWS disclaim and are
not liable for any claims or losses which may be incurred by third parties while relying on the
information published herein.