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Home My WebLink AboutCOM 0896.172 2022-2024DarVn Arai A ant August 19, 2024 Ms. Heather Kimball, Chairperson And members of the Hawaii County Council '- 25 Aupuni Street `' Hilo, HI 96720 Dear Chair Kimball and Members of the Hawaii. County Council: SUBJECT: Proposed Conditions regarding Bill No. 166, Draft 3 regarding proposed Amendments to Change of Zone Ordinance No. 02-131 Tax Map Key: (3) 7-3-024:003, Kaloko Mauka Subdivision North Kona Hawaii Please find attached a communication from the Applicant, Kona Three LLC regarding the above -described amendment to Ordinance No. 02-131 being heard as Bill No. 169, Draft 3, scheduled before the Hawaii County Council on August 21, 2024. The conditions are being offered by the Applicant in the hopes that it addresses proper drainage mitigation and the recommendations of the Cultural Resources Commission. Should you have any questions or require additional infonnation to assist with this request, please feel free to contact me. Sincerely, Daryn Arai Land Use Planning Consultant Encl: Applicant's communication w/ proposed conditions cc w/encl via email: Kona Three LLC y P.O. BOX 4501, I IILO HAWAII 96720 PHONE: (808) 895-3218 EN AIL: DARYN.ARAI@OUTLOOK.COFA M ,'",,J x 124a PROPOSED AMENDMENTS TO BILL 169.) Draft 3 (material to be deleted is bracketed and struck -out, with added material underscored) Amendment to Condition J regarding drainage Due to statements made by Director Steve Pause regarding Condition J, the Applicant discussed with Director Pause suggested amendments to Condition J that would accurately represent the expectations and requirements of the Department of Public Works. While Director Pause did provide the majority of the suggested language presented below, the Applicant did provide additional clarifying language to ensure that any required drainage improvements are to ameliorate any effects upon the existing drainageways that are directly related to the proposed project. [All development genefa+ed i-dnoff shall be disposed of on site and shall n , Wo fks review and appfoval. The pla* shall = ltide- system, a eenstmetion timetable fef all elements of the system, and an analysis of ]The Applicant shall manage all stormwater runoff generated by the project and shall not allow, to the extent that is reasonable and practical, an increase in project -related stormwater runoff to impact adja� cent properties. The Applicant shall include measures to temporariliMpound, detain, or retain project -related stormwater runoff during an event and release runoff in a controlled manner. Efforts to prevent impacts to water quality and utilize stormwater to recharge groundwater shall be made. Prior to receipt of Final Plan Approval, the Applicant shall submit a drainage master plan to the Department of Public Works for review and approval. The plan shall include hydrological and hydraulic calculations for all components of the project's collection and retention/detention facilities, design details for stormwater mitigation facilities, calculations that show how on -site facilities reduce or hold steady pre - development peak rates, hydraulic capacities of off -site culverts that will be affected by increase in stormwater volumes, a construction schedule to include milestones for completion of key tasks, and an analysis of downstream impacts, if any, directly caused by project -related stormwater runoff. New Condition memorializing recommendation of the Cultural Resources Commission As represented by the Applicant, it has every intention to incorporate the recommendations of the Cultural Resources Commission in order to facilitate a more sensitive project design that integrates the need to properly protect any important natural, historical and cultural features that exist within the project site. The Applicant therefore offers the following condition to be included within Bill 169: As recommended by the Cultural Resources Commission, the following information shall be pursued by the Applicant and integrated into development plans submitted for Final Plan Approval for any use or structure within the project site: 1) documentation of lineal descendant and kama`aina knowledge of the natural and cultural resources of the project area, inclusive of trails; and 2) consultation with members of the 146lualoa community, as determined by the Planning Director, in order to provide a development plan that includes larger open space areas that more sensitively integrate and protect the natural, historical, and cultural features of the landscape, including trails and other cultural sites, as well as natural features of the terrain such as drainage channels, and native plants. Daryn Arai Land Use Planning Consultant August 19, 2024 Ms. Heather Kimball, Chairperson And members of the Hawaii County Council 25 Aupum Street Hilo, HI 96720 Dear Chair Kimball and Members of the Hawaii County Council: SUBJECT: Discussion regarding Drainage within proximity to the proposed Royal Vista project relating to Bill 169, Draft 3 Tax Map Key: (3) 7-3-024:003, Kaloko Mauka Subdivision, North Kona, Hawaii Please find attached a communication from the Applicant, Kona Three LLC dated August 18, 2024 providing a discussion regarding drainage as it relates to the subject properties and the above -described amendment to Ordinance No. 02-131 being heard as Bill No. 169, Draft 3, scheduled before the Hawai `i County Council on August 21, 2024. Should you have any questions or require additional information to assist with this request, please feel free to contact me. Sincerely, Daryn Arai Land Use Planning Consultant Encl: Kona Three LLC Letter dated August 18, 2024 w/exhibits cc w/encl via email: Kona Three LLC P.O. BOX 4501, HILO H11wA[I 96720 PHONE: (808) 895-3218 EMAIL: DARYN.ARAT@OUTLOOh.COM Kona Three LLC 101 Hualalai Street Hilo, HI 96720 August 18, 2024 Ms. Heather Kimball, Chair County of Hawaii County Council 25 Aupuni Street, Ste. 217 Hilo, HI 96720 RE: Drainage Issues in vicinity of Royal Vistas Project Dear Ms. Kimball, Research on the drainage issues in the Holualoa Drainage System (drainage area including Royal Vistas) found numerous Reports and Studies of drainage and flooding in the area. The earliest study/Report that is still referenced and in use by the County DPW is the 1974 "North Kona Flood Control Project" by Shimabukuro (See Ex A, copy provided). As one would expect, there has been a lot of history since that Report was first published 50 years ago. Attached as Ex B please find a summary history of events related to drainage/flooding in the area and specific to our Royal Vistas properties attached. Plate 4 of the Shimabukuro Report shows the then existing path of the two major drainage channels/streams in the Holualoa Drainage System: the Holualoa Ditch (Stream), sometimes also called the Holualoa School Ditch; and the Horseshoe Bend Ditch (Stream). Attached as Ex C find an annotated Plate 4 showing our property and some other area landmarks relative to these two ditches. Plate 5 of the Shimabukuro Report shows numerous recommended drainage improvements within the Holualoa Drainage System, as well as their planned Phasing (I through V) starting at the ocean and moving mauka. The five planned phases included: I(a). New 30' x 10' channelization of lower Holualoa Ditch with debris and siltation basin from SW corner of Alii Kai subdivision to ocean, plus bridge over Alii Drive. I(b). New 30' x 8' channelization of middle Holualoa Ditch from above Kupuna Street to Kuakini Highway, plus culvert under Kuakini Highway. II(a) Improve existing channel to30'x8'channelization of lower Holualoa Ditch from debris basin mauka to Kupuna Street, between Alii Kai subdivision and Kamani Trees subdivision. II(b). New 8' x 4' channel between Queen Ka'ahumanu Highway and Kuakini Highway with a culvert under Queen Ka'ahumanu Highway plus culverts under the Kailua to Keauhou Road and Kuakini Highway. ll(c),New 30' x 8" channel un lower lioluaioa Ditch (County awned) from Queen Ka'ahumanu Highway to planned merger of Holualoa Ditch and Horseshoe Bend Ditch above Queen Ka'ahumanu Highway, plus new culvert under Queen Kra'ahumanu Highway. III(a). New 24' x 7' channel on upper Holualoa Ditch (County owned) to Mamalahoa Highway with a 30'span bridge across Hualalal Road. IV(a). New 16' x 7' channel on middle portion of County -owned Horseshoe Bend Ditch to merge with Holualoa Ditch mauka of Queen Ka'ahurnanu Highway. New 24'span bridge across Hualaloi Road. IV(b) New 16' x 7' channel from upper Horseshoe Bend ditch from Hualalai Road to Mamalahoa Highway. V(a) New 20' x 7' channel on upper Holualoa (Bitch above Mamalahoa Highway with 30' span bridge on Mamalahoa Highway, V(b) Improve existing Horseshoe Bend Ditch above Mamalahoa Highway with a new 24' Span bridge an Mamalahoa Highway - See attached Ex D showing enlarged portion of Plate 5 of area from Royal Vistas to the ocean with recommended/planned improvements, in the 50 years since the Report was adopted, a few of the steps recommended have been adopted, and they are italicized in BOLD above_ Phase I providing adequate outlet to the ocean of the drainage basin has not been started, there does not appear to be a plan or design for Phase 1, and acculding to Hawaii's Environmental Review Program there is no FEA for the project. The portion of the project planned for improvement on the Royal Vistas project is Phase IV(a), which is propcased to merge Horseshoe Bend Ditch mauka of Queen Ka'ahumanu Highway with Holualoa Ditch, after Phases 1-III are complete. There is no record of the County -owned Horseshoe Bend Ditch nor the County -owned Holualoa Ditch adjacent to the Royal Vistas property ever flooding, nor have these waters ever flooded Queen Ka'ahumanu Highway, where the State put Into place the two recommended culvert systems for the ditches to cross under Queen Ka'ahumanu Highway. Note per attached Ex E, the Report recommends two drainage crossings for the ditches across Kuakini Highway, but only one has been built for the Holualoa Ditch. The waters from. the Horseshoe Bend Ditch currently cross over the Kuakini Highway and not below it as no culvert system has been built, although recommended and planned in the Report. This i5 the source of the recurring floodwaters thot periodically flood nurnerous homes in subdivisions including Aiii Kai and Kuakini Makai as well as doing damage to County -owned Kuakini Highway. The last two substantial flooding events in this area both took place in the fall of 2017, and caused substantial damage. In order to address this problem, we approached two affected property owners where the floodwaters cross over their land (just above and just below County -owned Kuakini Highway), and both owners Kasser/Taube and Jandoo Inc. have agreed to work with the County and us to implement a drainage plan involving placing culverts under Kuakini Highway, We put forth a 'Proposal to the County last year proposing such a drainage improvement prnjpct (see attached Ex F inclusive), and we received encouragement from Mayor Mitch Roth, who indicated the County would get back to us after studying the Proposal. We now await the County's response. In summary, it seems to us that the re[:ummenderl iinprovements in the Shirnabukuro Report do not appear likely Lo be completed anytime soon, as the regulatory environment and the engineering science have changed quite a bit in the last 50 years. For instance, FEMA has doubled the "W of the Hnlualna Ditch and merging the Horseshoe Bend pitch into the Holualoa Ditch mauka of Queen Ka"ahumanu Highway does not appear possible. Also, completing Phase I of the Report's recommendations providing an outlet into the sea has become extremely challenging from an environmental approval standpoint, and there is currently no plan or approval to perform this essential Phase to my knowledge. We hope that, working together, we can at least address the existing problem affecting dozens of homes in Alii Kai and Kuakini Makai subdivisions who face the constant threat of flooding from Kuakini Highway and Horseshoe Bend Ditch. Thank you for your time and attention to this matter. Sincerely, Richard Wheelock Member, Kona Three LLC RAIN: raw Enclosures CC: Bobby Command w/Enclosures via email Steve Pause w/Enclosures via email paryn Arai w/Enclosures via email Michael Matsukawa w/Enclosures via email Lynne Taube w/Enclosures via email Dave Knittle w/Enclosures via email (Holua oa Drainage System) ( Ordinance II-b. 586 ) District of North Kona Col city of Hawaii a EXHIBIT A 0 F t41 ZX tit W S° �i � . r ,'-rd,"�Y. r ,. � � a r 4 � M �,,d ,` a t 1+yR• r r ,� x Ks - � � C ..-.• �^,. ,�y �. l ' � 4 w w �, k �, «� t 4 «r nt _43,ai J DO tJDT REMOVE OR LOAN OUT y THIS REPORT UNDER ANY y CTRCilT*L `1'�t1iCE . QNI.- 4' COPY! r- f orb a .,w�r' .,,,.... , n.,•r. ,. �' � , .; a ,.++'�,r�•„�,.4p� 'w �•.9 ' .,e ;� � °I • tl ASTER PLAN A REPORTFOR r h 1 NORTH • I{ONA FLOOD CONTROL PROJECT � �4 a •t.:. .��r � *st ,q (BbLUALWDRAINAGE 'DY;STEM) ORDINANCE hC). 5'86) tip. x ,� x L-k.0:..i.�~�'S ?k Ar' roc n ry-�, �T � r ^� i y �. y „0Y "H 4��A 1 I kv }'`�"'r;°c r � w� Y-•Y ��gg iie., Fv' y.�y' $` I ; q,*r^yT^M ," .c ,: "' r `t - #• a, AZ' rr �.�y", !( ""� q'? 3 '•� k- h i +�. �"dM1Y R'. "�,�-,m'�]"'•u �'yi � a M1 „ F�. C.� +• � ki+M » � yr. ' 5 .. • r 3 p�" 4 to 'r � � [l. �° �- � ��» +C a, dr',, �y�' £'� � : y � ��i �f '� gT � :+ " �r • � t �K�"r rw«' s��+�Jtr �� 1 A f F P � T�'F }'•� �+•,{ g q •"yid F �,•. �y� . y! • d+��Y[[1.tl L�i41* •. If tz NN r i a� f—w y + cp— .rc x3iici 711i:1�IC�IL'riT1C ILLS �Ci t� 3,-; Ir t �� Yy fi �yd�'rikre"°P"'gd �mm' "„''�'•ti,' ae r ',t .�•:. d�•+,�. 'Fad' -°' �"�+�,.,u% � s";;"l' .�,� �+�7•M:"^" "� 9.r i F aa 1 6� A F COLN`ITY OF ffil Ail TABLE OF CONTENTS I INTRODUCTION II HYDROLOGY A. Basin Characteristics B. Existing Drainage System C. Analysis TABLE I III Al igrnent IV 1AND OWNERSHIP V OTHER PROPOSED PUBLIC PROJECTS AFFECTING THIS PROJECT A. Alil Drive Realignment H. Kuakini Highway Realignment VI CONSTRUCTION PHASING A. Adequate outlet to the Ocean of the Drainage Basin B. Drainage Crossing on Kuakini Highway C. Need to Contain Storm Flows Within a well Defined Channel D . Provide Protection of Built-up Areas Along Mamalahoa Highway E. Provide :For Orderly Construction vil ESTIMATED COST LETTER OF APPROVAL OF ENVIROWE,: FTAL IMPACT STATEMENT APPENDICES A. Final Environmental Impact Statement B. Partial Parcel Map (Plate 6) C. Kuakini Elighway Realignment Study (Plate 7) D. Hydrologic and Hydraulic Computation REFERENCES Pa 1 2 2 3 4 9 10 10 13- 12 12 12 13 13 13 14 15 I. INTRODUCTION This Master Plan Report covers an investigation of flood problems and outlines a construction program for flood control structures in the Holual.oa Drainage Basin. The drainage basin is located about 2% miles south of Kailua. See Plates I and 2, Appendix A. It is bounded by the Waiaha basin to the North, Mount Hualalai to the East, the Kaumalumalu basin to the South, and the Pacific Ocean to the West.. The drainage of the basin is characterized by frequent flooding due to sustained and high intensity local storms. See Appendix in Appendix A for description of the Flood Deport of the Storm of 3--4 ❑ctober, 1968. The need for a flood control project in the area has been well documented in the references 4 to this report. The purpose of this report is to master plan the flood control structures in the area. It is not the intent of this report to justify the construction of the flood control struc- tures, but to determine design values, sines and types of y structures, estimated construction costs, general alignment and provide for orderly, coordinated incremental construction. The exact alignment should be determined after a detailed topographic survey is made during the design phase. i This report generally includes the following 1. Study of the basin to identify the flood problem areas. 2. Hydrologic study based on the current Hawaii County Storrs Drain Standards. 3. Field investigation and hydraulic study of existing 1 drainage conditions for 10 and 50 year frequency storms. 4. Cost Estimates and implementation plan. 5. Final Environmental Impact Statement. x 6. Hydrologic and hydraulic computations. 11. HYDROLOGY A. Basin Description The Holualoa drainage basin is Lang and narrow with an average width of 3,600 feet and a length of 32,000 feet. Elevation ranges from 0 to 4,180 feet from the outlet to the top of the basin respectively. Total area is 2,634 acres ( 4. 1' sq . mi.). The slope varies from 5% at the outlet to 12% at the top of the basin. The steepest areas of the basin are located immediately above and below Mamalahca Highway. Here, the slope is approximately 20%. The land use in the area is presently Residential, Agricultural, Orchards (coffee and macadamia rout farms) , Ranching, Village Commercial and Open. The built-up areas, r located in a strip along Manalahoa Highway and Alii Thrive, are generally comprised of small commercial shops, old residences, religious and educational institutions, a public - 2 - M building qnd a concrete products plant (Shields -Pacific). The existing zoning and General. Plan land uses are shown on Plates 3 and 4, Appendix A. The geologic formation of the area is generally comprised i of a than top soil. layer (0--10 inches) underlain by hard, basaltic rock. The rough surface and highly fractured 2' or 3' of the upper layers enables the ground to maintain a high infiltration rate and hence, rainfall must be intense 1 and sustained before runoff begins. The mean annual rainfall varies from 30 inches at the bottom of the basin to about 75 inches at the top. The Lower areas below 800 feet elevation are semi -arid with 3 low hushes, while the areas above are forested and in grazing grass lands. 13. Existing Drainage System The basin; is drained by two main dry, shallow "streams," the Horseshoe Bend and Holualoa School Streams, which combine below Kuakini Highway and above Alii Kai Subdivision. It then spreads out about 1,000 ft. from the ocean above Alii Drive, allowing most of the runoff to bypass the existing 5' x 2�' outlet, flow through the Shields -Pacific ` concrete products plant and over Alii Drive. e The drainage basin lacks well defined drainage ways except for a few man --made unlined channels constructed to temporarily alleviate the flooding of built --up areas. 3 I With the assistance of the Sail Conservation Service and r Hawaii County, property owners have bulldozed several thousand feet of channels. Generally, the natural drainage ways are shallow and difficult to define. Sizes of existing culverts and channels and their capacities are shown on plate S, Appendix A. All the streams are intermittent, having little or no flow during most of the year. Runoff generally infiltrates into the highly pervious lava formations and almost never reaches the ocean except during periods of intense and sustained rainfall. When runoff occurs, the roadways, trails and paths generally act as interceptors and divert flows to areas where drainage ways are sometimes non-existent and cause some of the flood problems identified in the area. Generally, the location of built-up areas in shallow basins without flood control structures causes most of the problems. C. Analysis The analysis of the drainage conditions and the proposal for construction of new flood control facilities in the basin are based on the fallowing: 1. Field Reconnaissance of the drainage basin. 2. Evaluation of runoff values for 10, 50 and 100 year frequency storms. `r 17 - 4111 4 3. 'Engineering judgment in selecting the design values. 4. Evaluation of existing drainage facilities based on the selected design values. 5. Slope of -the ground and roughness of the unlined channels when new facilities were sized. 5. High energy flows in almost the entire lengths of the channels. 7. Location of existing property lines. The results of the runoff computations are shown in Table Y with detailed computations included in Appendix D. The recommended design values resulting from Hawaii County Storm Drain Standards are tabulated in the first column. Several methods were used in computing the runoffs. The Rational Method (Q=CIA) was used to check the runoff for areas greater than 100 acres, assuming future urbani- zation of the land as shown in the General. Plan. The "C"' factor was weighted in proportion to the area according to land uses in computing the runoff. 1 The runoff figures of the Corps of Engineers were 3 obtained from frequency curves, which were developed using the stream gage data from the adjacent Waiaha water- shed. The watersheds of Waiaha and Holualoa are similar but the curves do not reflect future conditions. The runoff figures furnished by the Soil Conservation Service are also for existing conditions. The figures from the General. Drainage Master Plan are the highest and are probably conservative. It is expected that ultimatelyr only about 30% of the drainage basin ' would be developed; this area being hounded by the ocean and the existing developments mauka of Mamalahoa Highway. The heaviest -rainfall occurs in the virgin lands above and the urbanization of the low rainfall lower areas prob- ably will not affect the runoff significantly enough to { justify these high design values. The provided freeboard should be used to accommodate these extremely high flows should they occur. In addition., should unforeseen develop- ments occur and increase the runoff, channel capacities can be doubled by lining the channels when economic conditions are more favorable. Use of the Hawaii County Standard results in high runoff figures. Although these figures are for approximately 100 year frequencies, they should be slightly higher than ii the figures from the Corps of Engineers and the Soil Conservation Service to allow for some future developments P and are recommended for design. The prediction of storm runoff on the' island of Hawaii is very difficult due to many parameters such as the arographi.c peculiarities which affect rainfall patterns and the geologic youthfulness which affect infiltration rates. Of primary concern is the infiltration rate which -- 6 - is also affected by developments within the basin. The infiltration rates vary within the basin even in its almost virgin state. Also, the moderately steep slopes r k in the channel cause high velocity flows and the unlined surfaces may cause turbulent flows throughout most of the channels. Energy dissipators should be incorporated in the design. The uncertain runoff quantities and channel hydraulics dictated the recommendation for the higher a design values. All storm drain systems of future developments within the delineated Holualoa drainage boundary should be designed to cast the runoff into the proposed flood control channels. The shape of the channel was determined after field a investigation showed most of the natural stream alignment to be in rock. The sixes of the channels were determined by using Manning's Formula with n=0.04 in accordance with Hawaii County Storm Drain. Criteria. Freeboard is included in the depths of the channels. See Plate 5, Appendix A, for channel and structure sixes. The channel will be unlined except for transition structures at bridges and erodible pockets where Cement Rubble Masonry and/or reinforced concrete will be used. The unlined channel may cause problems of erasion and hence, damage to property. it is recommended that the County conduct field inspections of the channel and the improvements 1 I � 4 after every runoff producing storm, and perform maintenance and repair work until, the stream has become stabilized. Thereafter, the stream should be inspected and maintained w periodically. It is also recommended that the entire right-of-way, where disturbed by construction, be grassed. The siltation and debris basin will be unlined except for the outlet structure which will be constructed of reinforced concrete.. Volume of silt storage for the siltation basin should be based on the same criteria as the Keopu Flood Control Project Siltation Basin whose watershed and basin characteristics are similar to Holualoa's. However, records of siltation should be checked if they are available during design to verify the storage value of 1.8 ubic yards per cubic feet per second of runoff that was used. �T. High land values in the area may dictate the construction of a small basin with a higher frequency of maintenance work. The availability of County maintenance work force should be considered when the siltation basin is finally sized as frequent emptying of the siltation basin will not be required when the drainage basin eventually becomes stabilized. The drainage areas were determined from 200 scale aerial i photo contour maps furnished by the County up to approxi- mately 2,700 feet above Mamalahoa Highway. The drainage areas beyond were determined from U.S. Geological Survey Maps. g ul o t" o 0 H u 4 1 N li I Ln 7 U7 Ln .-i iX, W C71 • oI€�i ca to o o a [n Ln I Ln wa o H Q p r 4 Ol CCI� W LA 44 0 r- Q W U CD H t� L7 to ri z 01 W LO jxy O {J b O O Clr C5 d t�7 I[1 Q U C71 H r>r P4000 UQ A o i3r <A Ul� d iJ � tD O co t] Ol r-I r-I r-I C� 4. H pWr W O O p U LO Lf) Ln ko ID x z H W U) N 'Cp H rO�G S 4 L.0 co Cif sd � y O H-I F-I CJ LO rg A N I"o 1 1 I I r-i ri o• o t31 { ri 1 I 1 1 r-i ra h Kr Ill � L4 w I N ci ❑' Ou O Ln LO Ln 1 t- 47W r•i m fn to i r-I 1 N 1 r"] fry O o® Q O O CO co w v N iV N slr 4: co (n OR cr1 LS7 C) Ln 40 Ln ►o 03 O1 N r-1 ri r-# N N fr'I ,[C0 e LO r-rv OD H rv 00 r— OD O IT Ln n ri ri H N 0 0 CD LOao n o In 0 N N N r7 M r'Ri N d' Ul 0 al r3 N M M rYt b N W 0d rtl Q -4 fa tr IC 11 41 �,, M Qi 4 m - 4 IC w 41 � A> � -11 8 •i i 3 z tV) 3 i y r-1 N in UT C � �4 t31 3 �1 � t:;) r-I 41 *pp� I� r-4 0 4 a U Ri fi tz to D x M En •in 4I N rb aj rd 5 3 LI .I f-r m fd I to 0 u cd 1 m O ! of x 0 t4 0 0 0 Id $4 --3 to 0 06 w 41 .,1 Cl %4 0 (d rA x 0 rd rd r-I m �j © ul %. H f3 cd •r•f fw m r-i 0 r4 d3 - C ryI � O -P •r•4 N i 'rs: dS 4�7 to 0 -P I~ a: r f r 31 0 fll (d IA U Q} W ly cC > i }I x w H rl x H w VJ ±j 0 � .+ r-I N rn tr In LP O 1•� r-1 ■ Ui .r{ tp 15 44 t� CLr i4 4-3 U iU U9 L] O 44 pC O .14 •rl -A •rl rd Od [i 3 C = w rmi 0 O 4-) 1~ 4J co r-i N pp S•rt S•r la H U >1 >1 s>1 CA O to r-I O 'cl r-I r4 14 4 1 44 a 44 1� W 44 i? RS 'dp U) W II II II cx Oz Oi 'r' 111. ALIGNMENT The alignment of the channel has been generally kept in the natural st.reambed. This will enable future developments to more readily discharge their storm drain systems into the channel, which is at the low point in the basin. The location also results in the lowest amount of excavation and hence., an economical location. Where possible, the channel has been located to minimize the fragmentation of parcels which would decrease their values. A 15-foot maintenance strip with a .10-foot gravel roadway is provided for in the channel right-of-way. Turn arounds should be provided in the final design for long reaches of channels. Fencing is also recommended to control access. Attempt was made to combine the streams closer to the future Kuakini alignment to minimize the size of a second crossing. However, the moderately steep slopes, the topography, the proposed Kuakini Highway realignment, and the: required sharp bend dictated the combining further upstream. The combination of streams below Kuakini Highway was not economical due to the longer lengths of channels and two major bridge crossings. IV. .LAND OWNERSHIP Land ownership is shown on the Partial Parcel Map, Appendix B, Plate 6. The total land area required for this project is approxi- mately 26 acres. A total. of 51 land owners along the proposed channel will be directly affected by the project. It is expected that the County will purchase small sliver remnants of land that are undevelopahle, consolidate them, and sell them to the adjacent land owners. V. OTHER PROPOSED PUBLIC PROJECTS AFFECTING THIS PROJECT A. Alii Drive Realignment The Alii Drive Realignment Study by Belt, Collins and Assoc.. 1973, recommends a new route immediately Makai of 4 the Alii Kai Subdivision as shown on Plate 5 in Appendix A. Should this new route be constructed prior to the Holualoa Drainage System, the County should consider dead -ending the old Alii Drive at the old culvert crossing. Study should be made to locate and construct a spur road from the old to the new Alai Drive south of this crossing. B. Kuakini Highway Realignment The Highways Division, Department of Transportation, is in the process of preparing preliminary realignment plans for Kuakini Highway as shown on Plate 7, Appendix B. The preferred alignment is Line No. 1. A public hearing was held on July 9, 1970, but the selection of a final alignment in the near future is not probable. Regardless of the alignment selected, two crossings will be required on the existing alignment. The County should construct these crossings before making any improvements immediately above Kuakini Highway, as the existing 42-inch a pipe culvert is grossly inadequate. Presently, runoff from severe stories overtop the embankments and flaw along the shoulders before flowing across Kuakini Highway. Crossings a on the new alignment should be constructed by the State. VI. CONSTRUCTION PHASING The recommended construction phasing is shown on Plate 5, Appendix A. The construction phasing was developed on the following e priorities: A. Ade uate Cutlet to the Ocean of the Draina e Basin Presently any runoff -producing storm causes flood waters to flow through the Shields -Pacific Concrete Products plant and over Alii Drive. The shallow channel constructed to protect the Alii Kai Subdivision discharges directly toward the concrete plant. The continuation of this channel and the construction of a bridge on .Alin. Drive and an outlet to the ocean should have priority. B. Drainage Crossinc.; on Kuakini Highway Kuakini Highway is the major highway in the basin and should have adequate protection from rain storm damage. The highway should be open under all weather conditions so emergencies can be responded to with dispatch. Construction of any improvements .immediately above the highway would endanger the embankment and should await the construction of the two crossings on the existing Kuakini Highway. State -- 12 - b work on the new highway realignment should be coordinated with this master plan. a C. Need to Contain Storm Flows Within a Well Defined Channel The channels bulldozed by local residents can adequately contain the major flows from ordinary storm through the built-up area along Mamalahoa Highway. Where the drainage ways are shallow and underdeveloped, the storm runoffs from intense local storms oftentimes overtop the banks and s damage improvements and lands. This changing stream course I results in the deposition of rocks, mud and debris, and breaches on roadways in places where no culverts exist. Most of the overland flaw problems in the basin would be eliminated by containing the storm runoffs in well-defined channels. D. Provide Protection of Built-up Areas Along.Mamalahoa Highway Although the improvements constructed by the residents afford protection against the majority of storms, there is i still a need for protection against the 50-year frequency storm. The existing channels should be improved so the entire system will be able to adequately and safely convey runoff from 50-year storms to the ocean. E. Provide for Orderly Construction Construction of a gravity system should progress upstream. Generally, any improvements upstream should not be made until the downstream conditions can accommodate. increased flows due to improvements upstream. - 13 is VII. ESTIMATED COST See pages 43 and 44, Appendix A. a - 14 - EXECUTIVE CHAMBERS f"- MONOLULV J H N la U P2 N S Edward Harada County of Hawaii Department of Public Works 25- Aupuni StTeet Hilo., Hawaii 96720 SUBJECT: Environmental Impact Statement for North Kona Flood Control Pxoject (Holualoa Drainage System) holualoa, Hawaii Dear Mr. HaTada, Based on favorable -recommendation from the Office of Environmental Quality Control, I am pleased to accept the subject document which describes and discloses identifiable environmental impacts and responds to comments received during the review of the draft statement. This document fulfills that requirements of Chapter 343, Hawaii Revised Statutes and the Governor's Executive Order .of August 23, 1971. With'warm personal regards, I remain. Yours Very Truly, cc: OEQC GeVrge Ariyoshy t�ng Governor - 15 - F I N A L [l ENVIRONMENTAL IMPACT STATEMENT FOR MASTER PLAN OF NORTH KONA FLOOD CONTROL PROJECT (HOLUALOA DRAINAGE SYSTEM) (ORDINANCE NO. 58 6 ) DISTRICT OF NORTH KONA COUNTY OF HAWAII Prepared Pursuant to Governor's Executive order of August 23, 1971 by Stanley S. Shimabukuro & ASsociates, Inc. for the Department of Public Works County of Hawaii November 1974 4 TABLE OF CONTENTS Page I INTRODUCTION 1 II DESCRIPTION OF THE PROPOSED ACTION 3 III PROBABLE IMPACT OF THE PROPOSED ACTION 7 IV PROJECT ALTERNATIVES 11 V UNAVOIDABLE ADVERSE ENVIRONMENTAL EFFECTS 13 VS RELATIONSHIP BETWEEN SHORT-TERM USES•AND 14 LONG-TERM PRODUCTIVITY VII IRREVERSIBLE AND IRRETRIEVABLE 14 COMMITMENTS OF RESOURCES VIII DISCUSSION OF PROBLEMS AND OBJECTIONS 14 RAISED BY INTERESTED PARTIES IN THE REVIEW PROCESS PLATES 15 APPENDIX A 20 APPENDIX B 23 REFERENCES 50 I. INTRODUCTION This County Master Plan, when implemented, will alleviate or eliminate all of the flood hazard problems in the Holualoa area as outlined or identified by local residents; the Soil Conserva- tion Service; the Drainage Master Plan, prepared by R. Ph. Towill Corporation, August 1971; Flood Hazard Information, Report R37, September 1970; and most Flood Report, Storm of October 3-4, 1958, Circular C52, March 1959, prepared by the Corps of Engineers. The absence of adequate flood control measures such as deep channels., large bridge crossings, siltation basins and debris barriers, and diversion systems in the project area causes flood damages almost annually and tends to deter the safe and orderly growth of the area. As the area continues to develop, as it undoubtedly will, runoff from storms will increase and cause an increasing amount of damage. The Corps of Engineers' Report, "Storm of 3-4 October, 19581 i C-52" reported considerable damages in the Holualoa area. See appendix for excerpts. Presently, the small 5' x 2h' outlet to the ocean at Alii Drive is inadequate and cannot pass the storm water without overflowing and spreading mud and debris over a wide area before emptying into the ocean. The channel also spreads out and adds to the problem. The shallowness of the existing streams and the undersized culverts and bridges in the areas above the outlet cause over- topping of stream banks and overflows at culverts and bridges. 4 The construction of flood control channels and large bridges i with a siltation basin and debris barrier, and a series of i diversion systems is necessary to alleviate the existing flood 1 problems. The most economical time for construction of this project, if at all, would be now, when most of the land is undeveloped and open. Construction and Land acquisition costs would be at s their lowest. The total cost of this project is estimated to be $5,900 ,000. Cost of each phase and completion dates are listed in Appendix B, T pages 43 and 44. This statement is intended to serve as an aid to the Governor, the Mayor, County of Hawaii, and all other interested parties in their decision -making when weighing the beneficial `y and adverse effects of the project. Although this project is proposed to be constructed in phases, this statement is also intended to measure the impact of the total project on the Holualoa area. Each construction phase will have its own controls to minimize the temporary adverse effects. II. DESCRIPTION OF THE PROPOSED ACTION A. Project Area Description a The Holualoa Drainage Basin lies approximately 2h Miles south of Kailua-Kona on the slopes of Hualalai Mountain can s the Island of Hawaii. See Plates 1 and 2. The basin is long and narrow with an average width of 3,600 feet and a length of 32,000 feet. Elevation ranges from 0 to 4,180 feet from a the outlet to the top of the basin respectively. Total area is 2,634 Acres (4.1 sq. mi.). The slope varies from 5% at the outlet to 12% at the top of the basin. The steepest areas of the basin are located immediately above and below Mamalahoa Highway. Mere, the slope is approximately 20%. The basin is drained by two main dry, shallow "streams," 4 the Horseshoe Bend and Holualoa School Streams, which combine below Kuakini Highway and above Alii Kai Subdivision. It then spreads out about 1,000 ft. from the Ocean above Alii Drive, allowing most of the runoff to bypass the existing 5' x 2 ' outlet, flow through the concrete products plant and over Alii Drive. a The existing Zoning and Genera. Plan Land Uses are shoran in Plates 3 and 4. The land use in the area is presently Residential, • Agricultural, Orchards (coffee farms and macadamia nut), Ranching, Village Commercial and Open. The built-up areas, located in a strip along Mamalahoa Highway and Alii Drive, 0 1 3- are generally comprised of small commercial shops, old resi- dences, religious and educational institutions, a public build- ing (library) and a concrete products plant (Shields -Pacific). The ranching .lands are generally in Haole Koa and Kiawe above and below Kuakini Highway and in grazing grass above � Mamalahoa Highway. I Eighty percent of the land is forested with Ohia, Silk Oak, Monkeypod, Kiawe and Guava trees and Haole Koa and Lantana bushes. Eighteen percent is in grassland and 2% is urbanized. Crown densities of the forest range between 10 and 40%. The exact locations of the different types of forests, orchards and agricultural areas within the basin are available at the Forestry Division, Department of Land & Natural Resources. The geologic formation of the area is generally comprised of thin top soil layer (0-10 inches) underlain by hard basaltic rock. The rough surface and highly fractured 2' or 3' of the . upper layers enables the ground to absorb a large amount of rain before runoff begins. The Great wall of Kuakini crosses the basin immediately above the Alii Kai Subdivision, approximately parallel to the ocean. s No wildlife, except for local birds (mynahs, doves and sparrows), stray dogs, some mongooses and some insects, was q observed in the area. 4 B. Existing Drainage System The drainage basin lacks well defined drainage ways except for a few man --made unlined channels constructed to temporarily alleviate the flooding of built-up areas. With the assistance of the Soil Conservation Service and Hawaii County, property owners have bulldozed several thousand feet of channels. See Plate 5. Generally, the natural drainage ways are shallow and difficult to define. All the streams are intermittent, having little or s no flow during most of the year. Runoff generally infiltrates into the highly pervious lava formations and almost never reaches the ocean except during periods of intense and sustained rainfall. The roadways, trails and paths generally act as interceptors and divert flows to areas where drainage ways are sometimes non-existent and cause some of the flood problems identified in the area. Generally, the location of built-up areas in shallow basins without flood control structures causes most of the problems. Several culverts are located along Mamalahoa and Kuakini Highways, Holualoa Read and Ali.i Drive. See Plate 5 for computed runoffs, existing sizes of culverts and proposed crossing sizes. The computed runoffs (Hawaii County Criteria) show the apparent inadequacies of the existing system. C. Proposed Action -a% The following actions are proposed in the construction of this project to alleviate the apparent inadequacies (See Plate S): 1.. Taking of land in marrow strips for right-of-way along the general alignment of the existing streams. About i 5 - I twenty -sic acres of land, mostly undeveloped, for about 23,000 feet of channel will be required. All of the land, a with the exception of two State-owned lots are privately r owned. About 51 property [owners will be affected. 2. Deepening of the existing shallow streams to increase the w runoff carrying capacities (unlined). 3. The construction of wider bridges or culverts at all highway crossings to carry increased flows. 4. The construction of highway shoulder ditches, small culverts and diversion systems to eliminate uncontrolled sheet flows across the highways and private properties. 5. The construction of a siltation and debris basin. - W All of the proposed actions are considered to be permanent. It is expected that the deepening of the existing streams will be in rock except for small pockets of erodible material.. • The channel will be unlined except for transition structures at bridge crossings where Cement Rubble Masonry will be used. A four -foot high fence with gates is proposed to control access to the channel. Roadway for maintenance vehicles shall be 10 feet wide and have a gravel surface. Turn -grounds will be constructed for long reaches. Funds for this project have not been appropriated and the construction schedule in Appendix B, pages 43 and 44, is approximate only. 7 -6 I III. PROBABLE IMPACT OF TTIE PROPOSED ACTION A. Benefits 1. The almost annual flood damages will be minimized. 2. The new flood hazard area would generally be confined to the channel right-of-way. 3. Land values will be increased. 4. Most of the precious top soil would be preserved. 5. "Peace of mind" will be established with the residents, 3 ranchers, farmers and businessmen in the flood prone areas. 6. Promote safe and orderly growth. 7. Public health will be improved. 8. .Most of the mud and debris flowing across Alii Drive and entering the ocean will be eliminated. 9. Aesthetics of the area would be improved. B. Adverse Effects 1. About twenty-six acres of land in the flood hazard area would be permanently committed to flood control purposes. 2. Parcels of land will be divided. 3. Excavation will mar the landscape. 4. Rate of runoff will increase due to the shorter concentration time. 5. Storm water would be concentrated at one point instead of being spread out across several hundred feet at the ocean. 6. Noise levels from construction machinery will disturb this normally peaceful and quiet area. 7. Traffic will be disrupted when construction is"in the vicinity of the existing highways. S. Pollution from construction activity, such as dust and i engine exhaust, will occur. 9. Water service will be disrupted. The project will not displace any persons or buildings. Parcels of land that will be split shall be provided with adequate access and made developable. Grazing Lands will be reconnected by providing cattle crossings at locations recommended by the ranches. The twenty-six acres of land needed for this project are mostly located in the flood hazard areas. Lining of the channel to reduce rights -of - way acquisition results in a higher projected cost. The construction of this project will increase the land values of the flood prone areas and hence, a higher tax assessment will result. Tax payers may not see this as a 4 benefit, but anytime one's assets are increased, it should be considered as a benefit. The increase in rate of runoff due to efficient align- ment and fixture developments will be adequately provided for by the deepening of the channel. The concentrated storm water will eventually spread across the rocky coastline by continuous wave action. Although most of the mud and debris will be eliminated, the turbidity will remain. The siltation basin should be maintained and emptied periodically to insure adequate capacity for the next runoff producing storm. The silt and debris can be hauled to the County's land fill site near ' Keahole Airport for disposal. The effect on marine life due to dilution, according to the Research Center, Division of Fish & Game, Department of Land & Natural Resources, is believed to be minimal as storm water reaches the ocean only i once or twice a year on the average, and sometimes not at all. Inconveniences from construction activity are all temporary and will last about six to nine months for each phase. Since the project is stretched out, each specific area will be inconvenienced for a few months. Traffic inconveniences will be minimized by providing temporary detours and proper traffic controls. Pollution from construction activity will be controlled by the Construction A Specifications in the design phase. Disruption of water service will he held to a minimum by adjusting or relocating the water lines during hours of low demand, as is normally done by the Department of Water Supply. No known natural landmarks, recorded historical sites or archeological sites will be disturbed. The new channel will cross the Great Wall. of Kuakini at a point already breached by the construction of a temporary channel. The Kealahowaa i Heiau and Historic Site #10 -37- 2037 are well clear of this project. Historic Site #10-37-2038 is adjacent to this project and although the channel alignment does not go through the site, the State Archeologist should be consulted s prior to the drafting of final construction plans and specifications. No wildlife will be disturbed by this project. The recreational use of the rocky beach at the outlet i for fishing, strolling or beachcombing will not be affected. The new channel will enter the ocean at approximately the i same elevation as the existing and will not partition the Y beach. Post flood cleanup in seldom used areas is generally not done and the accumulated mud and debris remain for long periods of time. This adverse visual impact would be greatly lessened by this project and the general aesthetics of the area improved. The life styles of the people will not be affected by this project. - 10 -- IV. PROJECT ALTERNATIVES The alternatives to this project are: A. To do nothing and "live with" the flood damages and the constant threat of floods. B. Allow property owners to construct their own flood control measures. C. To disallow building in or to abandon the flood hazard areas. Alternative A would let the property owners suffer damages almost annually and progressively lose their precious top soil. There would be no "peace of mind" and the threat of loss of life will still be with these people. This would be unresponsive to the needs of the people in the area. The County would not have to expend approximately $5,900,000, the estimated construc-- $ tion and land acquisition cost. • Alternative B could result in the haphazard construction of a series of unrelated flood control structures which may, in turn, result in a costly reconstruction project when the area is developed in the future. Such piecemeal, uncoordinated construction would undoubtedly cause damages to abutting or adjoining property owners who have not yet constructed their own flood control ,improvements. Many legal problems could arise by this alternative. The County of Hawaii again would not have to expend $6,900,000. IE Alternative C can be accomplished by ordinance to control building in flood Lazard areas. This alternative would require too much valuable land for flood control purposes. Approximately one hundred people will have to be relocated. A large concrete s products plant, an elementary and intermediate school, several small businesses, some public and religious buildings, and at least two dozen residences would eventually have to be abandoned or relocated. This alternative would also be unresponsive to the needs of the people. The County again would save the $6,900,000 expenditure. - 12 - 1 . f i V. UNAVOIDABLE ADVERSE ENVIRDNMENTAL EFFECTS This project, when constructed or during construction, ? will have adverse effects on the environment. Most of these effects, as previously mentioned, can be minimized by careful planning, design and control during construction. The visual impact of the marred landscape in the lower areas (below Holualoa-Kailua Roads) will remain due to the absence of high foliage. The area is covered with low Haole xoa and scattered Kiawe trees. New subdivisions being con- structed adjacent to the flood hazard areas will expose the proposed channel more readily. The upper areas are generally well forested with trees, and the channel will eventually be hidden under this umbrella of trees unless the area becomes fully developed. As the area continues to grew, runoff will increase and the design runoffs may eventually be reached. Since storm r water runoff is natural and must be controlled for the protection of man, it cannot be ignored. The usage of land for the sole purpose of conveying storm water cannot be avoided. The concentration of runoff at one point was mentioned as an adverse effect, but since most of the mud and debris will be removed by a siltation basin and debris barrier, and the storm water will eventually disperse on the same beach, the overall effect may be a beneficial one. - 13 - VI. RELATIONSHIP BETWEEN SHORT-TERM USES AND LONG-TERM PRODUCTIVITY The construction of this project will immediately provide for relief from major flood damages, hazards and erosion. The project will establish a definite drainage pattern for the safe and orderly growth of this rapidly growing urban area. Short and long term uses will remain the same. As far as can be foreseen, it will not deny future generations usage of the encumbered lands for different and or better purposes. The future generations will be free of the constant flood threat that is now present. VII. IRREVERSIBLE AND IRRETRIEVABLE COMMITMENTS OF RESOURCES This project will commit land, labor and construction fr materials which are irretrievable. The only present and foreseeable use of this project is to convey storm water runoff safely and efficiently to the ocean. No other use is projected for this project in the future. Most of the action taken can be considered as reversible since, in essence, this project consists of deepening the shallow dry streams and leaving them unlined. VIII. DISCUSSION OF PROBLEMS AND OBJECTIONS RAISED BY INTERESTED PARTIES IN THE REVIEW PROCESS See Appendix B. 14 - UPOLU PT, K "Am LOCATION MAP NORTH KONA FLOOD CONTROL PROJECT HOL•UALOA DRAINAGE SYSTEM PLATE 1 �_ I" a '1 .•T,+J 1 W 04 OE �.� t•, `� ��-yam JN � ] ltJ.•-'"1"'..' J' i _��11 a —'r✓� 5 .. r It o qq uk r J - _Q tea— -�. .t _ � :• o � d� J � m in 9�,. �.� cy �RR-.`F�' •� k .n-i d z v'a st�ilb Y �?z{ n q (I ❑ -�6�+.. - \ t -i ... �•�fmppIrUGCIW ,wt 4 Q 4 13, a • r ' l t`- mom' p, - � I',rI [ j • 5 - -4. Is t cab J ' I 1/ F '•,~ 5 + "/ •�°yA V - � _ . - :t a •_ - , r1• VG _ :•fir-ls,J ...:o n31SAIS A5vNlwtj47 vl!vlvrl-lo"con - — F -10bl-LNOD 0001.1 VNOA H-LLAQN ONINOZ !Dr-JI-J-SIX:a E—j C7 71 - --------- - -- -)I- 0 0 rl ri 4, El Ll Lj In APPENDIX A Excerpts from "Storm of 3--4 October, 1968," C52, Corps of Engineers. "The upper- Holualoa-Kaumalumal_u areas were hardest hit during the storm. Three major washouts on the Mamalahoa Highway had an estimated damage of $116,000. Two of these washouts were new watercourses, one of which gouged a 50--foot by 10-foot-deep section from the road. The third washout destroyed three 48" pipe culverts and washed away a 100-foot long section to a depth of 20 feet. A 10-inch water line was broken, depriving residents of water service for about 18 hours: A temporary bypass road was constructed to handle the traffic around the larger washout. "Overland flaw rushing down from the highlands cut new paths through pasture lands and coffee fields. Many homes, business establishments, and churches were .inundated by the flood waters. Three homes were destroyed and several others were knocked from their foundations. Five families were evacuated from their homes during the flooding and one family had to be rescued by police and firemen. About 40 homes in J the area were flooded and 5 automobiles were destroyed. There were no deaths or injuries. "Privately owned dirt roads were scoured creating new channels. Tons of boulders, gravel, mud and debris were deposited along the highway and on adjoining properties. These new watercourses were as much as .40 feet wide and up to 10 feet deep. 20 '"Choice pasture lands were destroyed and the flood waters ruined the capability of the land by eroding deep gullies and washing away the top soil. Roads, fences, and water systems were also destroyed. Several heads of cattle were also lost during the storm. "Hualala:i Road, connecting Kailua and Holualoa, had about $14,000 damages from washouts and pavement and shoulder erosion. Wingwalls and culvert inverts were also destroyed. Hualalai Road, like Mamalahoa Highway, was closed to traffic for several hours due to mud, debris, flooding, and washouts. "Runoff through the higher pasture lands rushed down the slopes, destroying stone walls and road pavements, and deposit- ing mud, gravel, and debris along its path to the ocean. A watercourse 4 to 6 feet wide was eroded through backyards in a new subdivision. Lawns and carports were filled with rocks and gravel at another housing area. Several homes had water above floor level, and minor foundation damages. "Approximately $25,000 damage to road shoulders and guard 3 rails was sustained at Kuakini Highway. Boulders and debris on the roadway temporarily closed the highway to traffic but was quickly cleared by State Highway personnel. A bridge on Holualoa Road was also washed out during the storm. Damage to the bridge was about $20,000. "Before running into the ocean at Holualoa Bay, the flood waters sweat through an industrial yard with water up to 3 feet -- 21 -- deep. Gravel stockpiles were washed away or spoiled by the muddy water and debris. Loss of material and minor repair to equipment was estimated at $20,000. Just south of this area, the Magic Sands Hotel, a resort hotel on the beach, had about $17,000 damages from water and mud 1 foot deep in the building and parking area. Carpets, furniture, equipment and appliances 1 were badly damaged. Foodstuff and office supplies were ruined. The swimming pool was partially filled with mud and debris. Beach cottages and homes in the immediate vicinity were als❑ inundated with the muddy waters. "A four -mile stretch of A1ii Drive along the beach, extending from Kailua Day southward to Kahal.uu, received minor shoulder damages. Eany sections of the read were under water during the storm. Cleanup of debris and Minor road repairs on Alii Drive were estimated at $15,000. Damages amounted to $6, 000 at the Magic Sands County Park where a 75--foot section of the retaining wall was washed out. "Traffic on the three major roads was at a standstill for several hours during the flood. "The County of Hawaii declared the damage areas as emergency areas. The Stag of Hawaii declared the F{ona flood zone a disaster area. This latter declaration provided State funds for repairs of public facilities damaged during the flood. The area was not declared a disaster area by the Small Business Administration; however, loans for small businesses are available. ZA Assistance for individual losses will be in the form of tax relief." r ' 22 APPENDIX B VIII. DISCUSSION OF PROBLEMS AND OBJECTIONS RAISED BY 1 INTERESTED PARTIES IN THE REVIEW PROCESS - 23 - J .p m i}44 .* 49sa JClfIN A. BURNS , ;, � RICHARD E. MARLANU, PN.o. GpVERi R f �t INTERIM AIFlEC1iR 11��+�` ti �i�a�a.••j I Y ED TELEPHONE NO, i 54I-8915 STAi�f'+ Q iA11AiS� 3 19 OFFICE OF ENVIRONMENTAL QUALITY CONMOL OFFICE OF THE,GpV"IQFLY 550IAr--E AU444AS4,.. ,'.tii-}!S' Room 301 RONOLUCU. HAWAIi %VEi - July 29, 1974 Edward Harada County of Hawaii Department of Public Works 25 Aupuni Street Hilo, Hawaii 96720 ` SUBJECT: Draft Environmental Statement for Master Plan of Kona Flood Control Project (Holualoa Drainage System) Dear Mr. Harada, This Office has received seven responses to the proposed project, as of this date. An attached sheet lists the responding agencies. In our evaluation of the draft EIS (dEiS) and comments provided, this Office finds several areas in which the final EIS should expand discussion. The following comments are offered: r I. INTRODUCTION We recommend that the estimated cost, $6,900,000, of the protect be included within this section. Also, it is suggested that the number of phases planned and their c.ompletion dates be included. Although it appears that the project will alleviate or eliminate flood problems in Holualoa, Environmental Center asks, can they assume that no other flood problems affecting properties will exist there? 24 - a Page 2 July 29, 1974 11, DESCRIPTION OF THE PROPOSED ACTION C. Proposed Action Discussion Of -the five paints listed should be expanded. Size of drain, its capacity, and description of the phases should be mentioned in the final EIS. Discussion of how the channel will fit in with the planned project and the. work .involved to conform to the Dew channel dimensions, as indicated by Environmental Center, is also recommended. In addition, please be more specific when referring to the channel If deepening the existing stream will be rack lined and the chancel will be mostly unlined except at transition structures (p.6), is there a possibility of erosion along the sail banks? Because erosion brings the following comments from these agencies, discussion is recommended: 1. Water Resources Research center comments that since the design flow and size of the channel provide fairly high flow velocities that will erode the pockets, will some measures be taken to line these erodible pockets? 2. Carps of Engineers fins that discussion should include existing conditions of drainage basin and erosion control measures which may be required to reduce sediment production. 3. Environmental Center suggests basic practices needed for erosion control. Tag soil can be conserved if groper measures are taken. III. PROBABLE IMPACT OF THE PROPOSED ACTION Under Adverse Effects, item 4 leads to confusion and needs discussion. What is „shorter" concentration time? Environmental Center finds iten 4 a serious consideration. During heavy rainfall, fine-grained silt cannot be caught in the settling ponds and is carried out to sea. Consi- deration of the impact of silt -laden water on the coastal environment should be given. - 25 - 1 q Page 3 July 29, 1974 Reference made to cattle crossing on page 8 raises a question from Water Resources Research Center. Will the crossings be temporary bridges or ramps? Department of Transporation recommends the final EIS provide sufficient info'rmation concerning compliance with Water Quality Standards of this State. V. UNAVOIDABLE ADVERSE ENVIRONMENTAL' EFFECTS The last paragraph on page 13 is confusing. Why will the overall effect be beneficial? A discussion should be provided to explain it. V1. RELATIONSHIP BETWEEN SHORT-TERM' USES AND LONG TERM PRODUCTIVITY The discussion of the Long term productivity should be expanded to include the projected growth of urbanization 4 resulting from the flood control. Will the flood control increase urbanization? What kind of growth is anticipated? Residential? Commercial? Industrial? Where will the growth be concentrated? Will land zoning change hecause of this proposed prQjeot? Will growth be flood free? VII. IRREVERSIBLE AND IRRETRIEVABLE COMMITMENTS OF RESOURCES Once the flood control project is implemented, run-off • water from 'the rain will end up at the ocean instead of returning to the ground. Thus, less fresh water will be returning to the underground water source. A discussion concerning this point is strongly recommended. RECOMMENDATIONS Since only a brief summary of the letters were given, it would be advantageous to consider the comments individually. We recommend that (1)written responses be sent to all commentators including this Office, ixidicating how specific concerns were considered, evaluated and disposed; (2) all comments and your responses should be incorporated as an appendix to the final EIS; (3) a copy of the final EIS should be sent to those individuals that provided substantive comments to the draft EIS. We trust that these comments will be helpful to you in preparing the final EIS. Thank you for the opportunity to review the draft EIS. We look forward to the final EIS. Sin rely, 26 Attachment Richard E. Marland in* anim Diront6r LIST OF RESPONDING AGENCIES FEDERAL Department of the Army (Corps of Engineers) July 23, 1974 *Department of the Army July 2, 1974 *Department of the Air Force July 22, 1974 Department of Agriculture (S.C.S.) Aug. 2, 1974 STATE Department of Transportation July 15, 1974 Water Resource Research Center (UH) July 15, 1974 Environmental Center July 22, 1974 *Department of Land & Natural Resources July 29, 1974 Department of Health July 25, 1974 *Department of Agriculture Aug. G, 1974 COUNTY OF HAWAII *Board of Water Supply July 1, 1974 *No comments offered If 27 Umvermty 0- Environmental Center Maile Bldg. 10 a 2540 M100 Way Honolulu, Hawaii ID6822 Telephone (808) 948-7361 Qiiice of the Director July 22, 1974 fit �;a�0 W'1iJ (�U►'� . TO: Richard E. Marland, Director, OEQC FRDM: Jerry Johnson, Acting Director Jacquelin N. Filler, Assistant Researche rze'/M;�' RE: EIS for Kona Flood Control Project (Holualoa Drainage System) North Kona, Hawaii The Environmental Center has been assisted in a review of the above cited EIS by Mr. Tamotsu Sahara of the Office of Physical Planning and Construction, University of Hawaii. Mr. Sahara has raised several questions with which we concur. Rather than devoting time to paraphrasing his comments, we will present them in tr,e; r entirety: From the statement in the introductory section, it appears that this project will alleviate or eliminate flood problems in Holualoa. Can we assume that no other flood problems affecting properties exist In . Holualoa. A more specific breakout of land uses directly affected by this project is desired. A general land use description of the area is given. The Soil Conservation Service and the ,County of Hawaii have assisted in constructing flood control channels. tow does this channel fit in with the planned project channel? How much work is needed to make this channel conform to the new channel dimensions? -t A Reference is made that the flood control will increase land values. The florid control will be a factor in increasing the land value by eliminating flood hazards but this is not. the only reason for increase .x in value. The general acceleration of land values will also be a factor. 28 Richard E. Marland, Director, OEQC 2 July 22, 1974 The inference that "precious top soil would be preserved" must b-. modified. Top soil in the undefined flow area will definitely be saved after the surface runoff is confined in the channel. However top soil in the Holualoa area will only be saved from eroding if proper conserva- tion measures are applied to the land. For example, all intensively cropped lands should be contour farmed, diversion terraces built to control runoff, strip cropped,if large area is cropped and use of ground cover when land is fallow. These are a few of the basic practices needed to control erosion. Explanations should be given so the two conflicting statements on Pane 7 can be better understood. In the "Beneiits" section, Item 9 states "Aesthetics of the area Mould be improved." in the Adverse Effects' section, Itew, 3 states, "Excavation will mar the landscape." Will any provision be made to reduce the length of the Great Wall of Kuakini that need to be denzol i sued? Three alternatives are discussed. Have any others been investigated? Why was the SCS design not continued in the reconstruction of the project? have the passibility of USDA-RECP cost.sharing program investigated for this project? Upon completion of the project, what maintenance will be needed for the channel and the service roads? 1 In addition to the points raised by Mr. Sahara, we find a few additional areas where somewhat. more detail would be appropriate. Pg. 7. 'Benefits Care should be taken that the construction of a modest drainage system will not lead false security to the previously flood hazard limited area and thus prorate greater growth in areas still subject to longer term flood damage. The social , environmental, and general impact on cornmunity services of opening of land area for development which had heretofore been subject to flooding and therefore unsuitable for housing should be discussed in the final EIS. Adverse Effects One of the more serious considerations is mentioned in item 4 under this topic. with increased rate of runoff and higher velocities, greater quantities of silt and debit will be transported. The settling ponds should catch the larger material but fine-grained silt will not be retained during periods of heavy rainfall and will instead be carried to the sea rather than being deposited on Lhe flood plain as in the past. Consideration should be given to the impact 29 - G Richard E. Plarland, Director, OEQC 3 July 22, 1974 of this silt laden stater on the coastal environment. It is an unfortunate fact that siltation catchment basins do not trap silt under maximun flood conditions. We agree that the "effect on marine life due to dilution (pg. 9) would be minimal;" however, the effect of the silt and turbidity may well be, significant. cc: T. Samara 0 . .. 3 o 0EPARTMENT OF THE ARMY HLADQUART LRS UNITED STATES ARMY SUPPORT COMMAND, HAWAII APO SAN F'RANCISCO 965$7 2 JUL Office of Environmental Quality Control Office of the Governor r 550 flalekauwila Street, Roam 301 Honolulu, Hawaii 9681.3 Gentl emen : The draft Environmental Impact Statement for the following project has been reviewed: Master Plan of Kona Flood Control Project (Holualoa Drainage System) (Ordinance No. 585}, District of North Kona, County of Hawaii We have no comments to offer. Sincerely, CHARLES S. VARNUM Colonel, CE Director of Facilities Engineering .. 31 _ 1 9 r VL_,"A;R Tt,"N f O i fli AIR F©RCYr'. FiEADQL+JIRYERS ;516 Alai M,4i - WING WACAF) APO SAN FRANCISCO 96553 l�L• L'L•�.ly+ a t.a n• n..zz 11,r KiT.iura f 4492 D aft Environrentai impact Statement - - O f Ce of ELivir[i:7Y;,.^.ntal Qurnlizy Control Odic: of thn Governor F T(Ani 0,: c Lcc Duildin,- 7looz - two v,.Ln t rC.'lativc to i;i:Q d-z aft environ- u,:lii..i-1 u. MW Yif3ani Maui, Hawaii i). Kona 2100d Project Z4, 'rLLAN CIF. A�r�Au}�i AsstaepComdr cr-CW* aiS,iW'wr •,ti ° 32 - 1 u n '+�tiF H1'�I Lt�•1` July 1, 1974 DEPARTMENT OF WATER SUPPLY c COUNTY OF HAWAII P. 0.. Box R020 . "ILO, HAWAII 0$720 25 AUPLJNI 5MEET {office of Envi.ronmeatal Quality Cantr+ol Office of the Governor 550 llale,cauwila Street, Room 301 Ronolnlu, M 96$13 Re: Environmeiital Tm-1paet Statement for Master Plan of the Kona Flood Control Project iolttrtlal l) :tiz 'cs*e System, Orclinnnen No. 5E61 ,_County of liawai i Thy proposed flood control project will have no significant adverse effects on our water system, n f� Akira Fuji ato :Manager r 1rtis 33 a au., ti .,Nhd 6�r:nr,efh -"k i ♦ f .: 54 STATE DF HA'WAII DEPARTMENT OF TRANSPORTATION 869 PUNCH13OWL STRLET HONOLULU, HAWAJI 9013 July 15t 1974 t. ALYF.Y ►w NYl.NI OIkYCCYOM JAWRCNCE F O E4+IJN Drrui+ p.wEC18R MUNNY Y A! LEE OL►uiY pJR(.+OR D OUG LAS 5. SAxAmOTO DC►• Y DIJ+EGTDJJ IN REFLY RCYLOt TOr ATF 8.2631 Dr. Richard J . i:arland Interim Director office of Environmental Quti_l.ity Control 550 flalekauviila Street iionolulu, Hawaii 96813 Dean Dr,. MIarland: Subject; Environmental Impact Statement Kona Flood Control Project (Holualoa Drainage System) In reference to the above subject statement, we make the following C Oft1T� E T1t S 1. It is recommended that the EIS provide sufficient information to indicate compliance with the water quality catandardra of the state. 2. The completion dates for various phases of the project should be approximated to assist future planning activities. The statement should indicate assurance of coordination with the Department of Transportation by the initiating agencya r sinoerelyr T � B. -Z 1- 1GH Director 134 — ' a L N IVE1 SI`IY OF HAWAII ` j�';Ll�:r �.��.'.l;liY'�:S �ii,•l�w�i �LILpj Office of Lbo IDLrctar MEMO AMUM July 15, 1974 MEA.b TO. Richnrd E. fi:irland Interim Director, QEQC MIN: Reginald H. F. 10urig'y" AssL. jirector, L,WC + SUBJECT: Draft EIS, holualoa Drainage System, Kona The subject EIS was reviewed in this office and the following brief comments are submitted for your consideration. During the deepening of the existing stream to they rock base will some racasures be taken to lane pockets of erodible material? From the design flow and size of channel, fairly high flow velocities may be reached which can erode these pockets. For the parcels of land divided by the channel, what type of cattle crossings wi11 be provided to reconnect grazing lands? Will they be Lt-¢ijporary bridges or ramps? K[1FY: jMn cc: -a. Gee J. Johnson 35 DEPART;lchlT OF THE ARMY HONOLULU DISTRICT. CORPS OF ENGINEERS BUILDING 9G, FORT ARMSTRONG HONOLULU, HA'WAII 96813 23 July 1974 Dr. Richard Harland, Interim Director office oL Environmental Quality Control 550 Halekauwila. Street, Room 301 donolulu, liawai.i 96813 Dear Dr. Marland; We have reviewed the draft environmental statement for the Master Man of the Kona Flood Control Project (Hoivaloa Drainage System) (Ordinance No. 586) District of North Kona, County of Hawaii, and have the following comments: a. The final EIS should include discussion of the condition of the drainage basin and its vegetation with regard to erosion control measures which may 'be required to .reduce sedime:tt production. b. The final EIS should include discussion of a flood plain management alternative to the recommended structural measures. Sincerely yours, ELROY,,.0 I� eN Act' Chief, Engineering Division 36 - F ,101IN A 1101INS fin` ay.rvgruu)A(Jr IAAWAII STATE OF HAUWAIII DEPARTMENT OF HEALTH w a Box 1378 HONOLUi.U. „AWAii%. 94f J11iy 25, 1974 II,: 11r. Iticl1.11'tl J�'. hl.lrLrintl, illtc•I-im I)ir(ICL(IT- of f ic.e o f I?.HV i,rO1111C`T1t;il I�k1u1,1J ly CrsnLroI I rTuTl; Director of licalth WALTER D, OUISENBERRY, M-P.H., M.D. p+nY.Cion or HFA1 TH Wit SUR S. LUMMIS JI: , M 5 . M D r1rPUTY DLnFGTOR or WALTw RALPH B- BERRY, M,P-H,. M 0. DEPUTY DIFIFCTOIR OF HFALTH �HENRI P. MINETTE, M.P,4.. 011I,P.H. DEPLOY DIRECTOR Or HEALTH In inr y Banco rv'�nr 4. Fike Uf'R%-1-FR e - Salbject: Draft Environmental Impact StaLemenL for Mnstcr Plan for Kona Flood Control Project: (llolualoa Drainage Syntem) ((Ordinance No. 586) The Pollution Technical Review Branch of the Department: of Health haq rewiewed the subject dx'aft Environmental Impact Statement and submit the following comments: Dwiring construe_tion all. wnst,o mai t.or penc-rnted shall he d:lspuavd all :tl proper l ind t ill sftes. Also, S f l t•ra k-in and debris basins shall be prupr•riy maintained to prevent Lhe necllmulat-ion of undesirable material that may tlec.reaso the efficiency of the basins. 00w r advurso c Clr. ct:-s satwh as kj1 ,J.t-i.ve duot . noise an,l traffic 1+ri,hlvnis should be- kept to a minisuultl. A WALTER B. QU NBERRY, M.D. 37 — POVIN A 61'11RNS r OvfANryR Df 11AWA11 STATE OF HAWAII DEPARTMENT OF I AND AND NATUnAL RESOURCKS P. o. Box 621 HONOL.UL,V, NAWAII 94609 Judy 29, 1974 rti��kifl��nr•r��UM DIVISIONS • cavv£r•Ncca rrvri ANn 6AMR sQ-EITr1T LANs MANAGKM1Lkt arArc YAmkt WAT[R AN12 LAND DrY£Lp/M[NT t 1". Marinn(l, InLorim Di.rec Lar Office of Environmental Quality Control 17'roni: Sunac Kido, Chairman and Member noa,rd of Land and Natural Rcsnurces � >>,I) {•ctComments on EIS for the Master Plan of the Kona Flood Control Project This Department has reviewed the EIS presented by the Depart- r—ni of Public Works, County of Hawaii., covering the faster Man { uF (lio Kona 'Flood Control Project, Ordinance No. 586, No;th Kona, Tlnwaii . 14e have no objections to the proposal as presented. Sincerely yours, BOARD OF LAND AND NATURAL RESOURCES SUNAO KIDO Chairman and Member 38 UNITED STATES DEPARTMENT OF AGRICULTURE SOIL CONSERVATION SERVICE 440 Alexander Young Building, Honolulu, HI 96813 August 2,1974 Dr. Richard E. Marland Office of Environmental Quality Control I 550 Halekauwila St. --Roam 301 Honolulu, Hawaii. 96813 Dear Dr. Marland: Re: Draft EIS pursuant to Executive Order, Plan of Kona Flood Control Project (Fiolualoa Drainage System) District of North Kona, County of Hawaii, June 1974. We have reviewed the above -mentioned draft as you requested. The follow- ing comments are offered for the. consideration of the planners: High -velocity flows from the upper areas of the project may oayse high rates of erosion in the proposed unlined channels. Many areas in these reaches are composed of fractured rock underlain with ash and cinders. As a result, there may be a larger amount of deposition in the lower, flatter part of the channel, requiring extensive maintenance and clean out. Alternative H could be a feasible approach to the problem by requiring that flood control, measures be in accordance with the County General Plan. Alternative C also appears to be a logical approach to the problem if a combination -of flood plain management and flood insurance were utilized, since the greater part of the area is undeveloped. The type of construction proposed in the project will cause the generation of debris from more than one storm. Because of this, it will be important that the proposed debris basin provides an adequate amount of storage. There may be a need to install farm crossings at various points along the channel, so that landowners will have access to their property on both sides of the channel. t - 39 �- Der. Harland In past years the stream flaw from Waiaha was diverted to Luawai Reservoir and overflow from the reservoir outletted into Holualoa Stream. Huehue Ranch has, in addition, diverted their water into Waiaha Stream. These modifications should he considered in the design of the proposed diversions. Thank you for the opportunity to review this draft. Sincerely, , rlere, Franois C. R. Lum State Conservationist 0 _ 40 1 r■?� « y r� JOHNA.BURNS `* r�ir�'l�t✓ jT QDYERNDA �� `£4ir�' �ar i STAT9 09 HAWAN$ ' [Dr—PARTMENT OF; AGRICUe_l"URE IA20 60. KINO STREET HON4LVI..V. t.AV/Ale P6014 August 6, 1974 MEMORANDUM TO: Dr. Richard E. Marland, Interim director Office of Environmental Quality Control SUBJECT: Draft Environmental Impact Statement for Master Plan of Kona Flood Control,Project (Holualoa Drainage System) (Ordinance No. 586) District of North Kona, County of Hawaii FREDERICK C. ERSXINE CHAIRMAN, BOARD OF AG RiCVLYWRE MLLIAM E. FERNANDES _ DE1VIY 70 THE CHAIRMAN~ The Department has reviewed this draft statement. This type of problem results from unrevised land use zoning. Past decisions failed to recognize the great hazards of stream flooding which future review should prevent. It is essential to provide for flow velocity reduction and sedimentation to prevent discharge of sediment into the ocean. The most important benefit will be improved protection of areas designated for urban use. The place appears adequate to reduce losses due to flooding. Direct agricultural impacts relate primarily to grazing areas. The proposed improvements will have no serious impact. Thank you for the opportunity to review this statement. Frederick C. £r4s�i ne Chairman, Board of Agriculture 41 A. INTRODUCTION The estimated cost has been extracted from the Master Plan Report and is attached. Completion dates which are included in the cost estimate are approximate, as no definite time table has been set for construction. The number of phases and the extent of each phase is shown can Plate 5. Some local flood problem will still exist but can be corrected once this project is constructed, as a point of discharge will be established. The flood control project will serve as a "spine" for all the collected runoff within the basin. This project will also enable new developments to have properly planned drainage systems. The County will consider submitting an application to the U.S.D.A.'s Resource Conservation and Development Cost - sharing Program for approval. if approved, the County may request for funding to implement this project. 42 VII. ESTIMATED COST The following estimated costs were developed using current construction costs and should be adjusted for escalation when this plan is implemented. The phasing of construction is shown on Plate 5, Appendix A. ESTIMATED COST (SUMMARY) PHASE I: Outlet Bridge Channel Siltation Basin Miscellaneous Total Construction Cost Planning & Engineering Right -of -Way Cost Total Estimated Completion Date PHASE II Channel Bridges Culverts Miscellaneous Total Construction Cost Planning & Engineering Right -of -Way Cost Total ECD - June, 1933 PWAq rrT- Channel Bridges Miscellaneous Total Construction Cost Planning & Engineering Right -of -Way Cost Total ECD - June, 1986 (ECD) - .Tune, 1980 $ 100,000 80,000 335,000 263,000 156,000 934►000 187,000 1,206,000 $ 2,327,000 453,000 60,000 20,000 107,000 640,000 128,000 1,176,000 $ 1,944,000 $ 573,000 120,000 139,000 832,000 166,000 130,000 $ 1,128,000 43 - PHASE IV: Channel $ 506,000 $ridge 96,000 Miscellaneous 120,000 Total Construction Cost 722,000 Planning & Engineering 144,000 Right-nf-Way Cost 137,000 Total $ 1,003,000 ECD - June, 1989 PHAgF, Ut Channel $ 265,000 Miscellaneous 53,000 Total Construction Cast 318,000 Planning & Engineering 64,000 Right -of -Way Cost 72,000 Total $ 454,000 ECD - Jane, 1991 TOTALS FOR PHASES I, II, III, IV & V: Total Construction Cost $ 3e446,000 Total Planning & Engineering 689,000 Total Right -of -Way Cost 2,721,000 Total Estimated Cost $ 6,856,000 Construction Cost, not including planning and engineering and right-of-way costs for each phase has been kept below $1 million. Planning and engineering includes surveys, design, sail investigation, construction inspection, contract administration and general administration costs. - 44 B. DESCRIPTION OF THE PROPOSED ACTION The sizes and capacities are shown on Plate 5. The extent of each phase, the structures included, new and existing channel widths and depths are also shown. The new channel alignment will coincide with the existing. The amount of work required on the existing channels to conform to the new channel size is indicated by the dimensions of the new and existing channels. Erodible pockets encountered in the channel excavation will be lined to prevent progressive erosion. Ranchers William Paris, Jr. and Peter L'orange, and District Conser- vationist Arch McCabe have suggested planting grass for erasion control along the entire Fight -of -way, including the maintenance roadway where the existing ground is disturbed by construction. Their suggestion will be incorporated in the Faster Plan and final design. Controlling sail erasion within the entire drainage basin is beyond the province of this project and would require a soil conservation project. The benefit of preservation of top soil is incidental to this flood control project. High energy flows will be controlled by the incorporation of energy diss.ipators in the final design. These energy dissipaters will be located in critical areas where the alignment is bad and dictated by criteria other than hydraulics. The exact locations of these energy dissipators will be established during the design phase. Diversions for stream flow constructed by the ranchers will be accounted for in the final design. - 45 -- C, PROBABLE IMPACT OF THE PROPOSED ACTION In any drainage basin, there is a natural length of time in which runoff from the entire basin begins contributing t❑ the volume of flow pass a given point. If the character of the basin is altered in any way, such as improving the hydraulic efficiency of the channel to concentrate the runoff faster, the result would be a shorter concentration time and hence a higher rate of runoff since the same volume of runoff must pass the given point in a shorter time. It is agreed that all the fine-grained silt cannot be trapped by a basic type siltation basin unless the basin is large enough to retain all the flood waters. The generation of fine-grained silt and the eventual discharge into the ocean is an unavoidable impact of this project whose primary concern is to eliminate or alleviate flood hazards. Sediment and erosion control are important and necessary considerations but should not be the only considerations. in lieu of a sophisticated and expensive study to determine the effect of silt -laden water on the marine environment, it is offered that this flood control project will reduce the amount of silt generated by containing the runoff in the channel. The flood waters will not be able to jump the channel and flow overland, causing erosion as it now does. The existing condition, which spreads mud and debris over a wide area, would be improved. This belief also resulted in the "conflicting" statement, „the overall effect may be a heneficial one." - 46 The cattle crossings required will be ramps with gates and locks. When the cattle have to be moved for grazing, the ranchers will operate the gates and locks. Keys for the locks will remain with the ranchers. Any faun crossings (bridges) required will als❑ be provided for in the final design. The design of this project will incorporate features as necessary to comply with the Water Quality Standards of the State. The construction work at the outlet area will be kept to a minimum to preserve the aesthetic and recreational value of the beach frontage. Since the construction of this project will reduce the amount of erosion now occuring, the addition of the silt and debris basin should maintain, if not improve the existing condition of the beach area. The two conflicting statements "Aesthetics of the area would be improved" and "Excavation will mar the landscape," result from the attempt to just list the probable impacts of the proposed action. An example where both beneficial and adverse effects could occur from a single action would be the use of pesticides. The statement "Aesthetics of the area would be improved" refers to the mud and debris that would be concentrated in the silt and debris basin and hauled away for disposal instead of being spread out over a wide area as is now occuring. In general, any excavation in a natural landscape would have an adverse visual and physical. impact. 47 D . PROJECT ALTERNATIVES Alternate C can be expanded to include Flood Plain Management. Under this alternative, the County can control building in the flood hazard areas by specifying floor elevations, flood proof structures, or restrict the con- struction of flood damageable structures in the area. Land uses may be changed for more appropriate uses in the flood hazard.areas. These land use controls would be enacted, administered and enforced by the County. More details of Flood Plain Management can be found in Reference 3. E. UNAVOIDABLE ADVERSE ENVIRONMENTAL EFFECTS In any proposed action, there will be beneficial and adverse effects. When benefits are weighed against the adverse effects, the overall effect could possibly result in favor of benefits. The proposed action in this flood control project will concentrate the storm water at the outlet to one point as apposed to the sheet flow now occuring which spreads mud and debris into Holualoa Bay over a wide area. With most of the mud and debris removed and the concentrated storm water being spread out by continuous wave action, the end result could be a beneficial one when compared to the existing condition. - 48 - F . RELATIONSHIP BETWEEN SHORT TERM USES AND LONG TERM PRODUCTIVITY This flood control project is not expected to signifi- cantly accelerate urbanization in the.. area. The areas of .new growth and whether any new growth will fallow the present land use designations are not known. Any changes that may occur as a result of this project cannot be determined at this time. All new growth is expected to be .flood free. G. IRREVERSIBLE AND IRRETRIEVABLE COMMITMENTS OF RESOURCES There are no existing around water sources in the drainage basin. The Department of Land and Natural Resources does not foresee any ground water developments in the area. This flood control project is not expected to have any significant effect on the existing main source of water supply in Rahaluu, which is located approximately two miles south of the drainage basin. 49 U ILI /� � j\ \ lu 7L 7.,j D s Ld I ;HFCKEa sY: fTRnLEY !. lHiMMUKUP0 G A11oc1 ATa,, inn. CIVIL AND STRUCTURAL ENGINEERS JQRK DESCRIPTION: Ilonoiulu. Hawaii 1)?--n Chan � PR o f CCona Flood corlir o l F -CICC-" DATE `5WEE1' � QF� CLIENT: H;*-�� i i Cour Chonnc.1 Side Slo ' MDnninds' arrnur� = �. Mzl nnimS!&' "r7 " Vaiuc : Q. 04" (fnr r-ock,smocih 11 unlfcrm .1. Los ,. = C� T-7 / b%s 1`2, sown for !Cf Des i n Channel ()>C th - d,4 FD. Open Chonnc1 R drEul' s , VTChca H� ndbook, of 1r'�U1;c �< nc:� 4 13 r-R+c,r (J �ioiucilan Dra nnge bas o of Alii Dr- � Outlet A:- Acres pLj b K R Qn b% _(3100x .00/0699 1LP4) - 0.12 dnib - 0. 2 �4 do - 7.02` V-Q/AF15.7fps rc : a 1 v/�: 0-` � 02S i4c = 7.5` C •Supercri�ic,al Flow) 1_2t0.a-is v dr,- p LA to 1 .1 0.0 App. D UtSluryt0 BY: CHECKED BY: l I nnLEY X fHIMABU URO G Elf CIATU1, inc. CIVIL AND STRUCTURAL FNGINEr-,RS WORK DESCRIPTJON: Honolulu, Hawaii Open DATE: MST- 1)197+ S"E£T _OF PROJE 7; C IENT: Chan net Ocrtki Kona Food Conirc>l gwal i Cwnly 951r eom lnferscLI' lon Miuka cf KC toiksni Wall w Arcc15 G) ihru 0 A - T5G Ac. 5= 8°/10 Usc- b 30` (345o x .04).Nq9-x, �-t18) ar _ :' l use- 8' V = 4 . P5 -t --�- dr-lb0.238 del 7. !4' (= - 5upc-rcricot F.'D. - 3,0 30, ()x 3400 c'PS v- 2+3 ,fps S - 0.c8 11. n-0.04 (Drse-shoe bend �, Halunla(:� Sch.Sirec ms Mciukp of Kuakini H�hwoy Rec►l is nIane ni — Areas Q ihru 0 Qw 3400 cfs s = 8%, Use, SQrroe 5ecti©n os above App. D �m DESiGN£D BY: . � rT CHECKF,a BY: fTAnLEY f IHIMPBUKURO G WfOCIRTEI, inc. CIVIL AND STRUCTURAL ENGINEERS WORK DESCRIPTION: Honolulu, Hawaii Open SHEET 2 OF-q- CLSENT:, CHnnmc1 p�o�E�T:Klor�l� K c)rzi Food Conic o! Frcyecl �wctIi rxfy HojuoIoa School Sirenm - lnfe--seciton - P,reos Q(D,C9 4 a ar2,�oocf� . ;w{u b: 17.r-;,G Use b ='.4' KQh/ bS13s1r-2 �n { 0. t 49 4' �Lb-ofps =G.48' (E>upercrIHcA Flow) Use: 7' Q ao cis �j n JOB NUMBER: DATE; m-ar. R11C91} �r3.59 dG '.4S App, 1) DESIGNED BY' CHECKED BY: fTnntE f f, J H [M BUKUR© G 1 i/J OCIATEJ' inc. CIVIL AND STRUCTURAL ENGINEERS WORK {DESCRIPTION: Ilonoluiu, Hawaii Open Cat tnn 1 9or`h iCQn;Q Flood Control Pr��' H ol uGl 10a ri0viSir- caIro a1uA 10ct- Kai J uca Rd - AreaS A- Ac-res b - 1 use: do iCG 2- 3 oQ/ 611 - 1. :�g L d r 0.35 area bcard 5 3,1 l ' 6.1 use 7 to s Q� 22-5v c,�s V 34.�4fps � CJ•��5 2v ` 3.11 Joe NUMBER: DATE: mv r. 1 D 1 �)-74 SHE£T-A—C1F-3— CLIENT: Hnwcti; Cyt. niq D,(E) a,( App. D DESIGNED BY' 4, a -�. CHECKED BY: MMEY f fHIMRBUKUA!B G AMCIRTEl, inn. CIVIL AND STRUCTURAL ENGINEERS JOB NUMBER: GATE: N4p-jr. ,,,D-74 WORK DESCRIPTION: Ilonolulu. tlaWa,l SHEET— ,,EET5 OF � Pn0JECT= CLIENT: charnel I Klar'��l Kona Flcood Con+ral Prc c- )lcHai schcol 5fre,nm � mnmainkoca Hwy Area A•1140Ac. 'L 0.09 5 I�� r 2 C)q � ITT' Use 2-0, c�,�jb-2o,�.a3 d I) = 4 , o GI' v = �-4.o fps 5b / b-'I-z _ I. -10 SUpeT-crificol How) Use.7' oqlm Q -15Q cfs v = 24 fps n t 0. 04- i d n = �- `� d c App, D SSCNED BY: ! I 1-f tECKEDBY: 1TRnlEY I. IHIMAOUKURO G MOCIRTEI, inn. CIVIL AND STRUCTURAL ENGINEERS JOB NUMBER: DATE.: VORK DESCRIPTION' 110110lulu, Hawaii OOpen $HEE1'� OF� PROJECT: � CLIENT; C�honnel North Kon-,z Ficx>d C�n�Fcl �'rcieci Hnwc6i Couni Horsesh7oe bend Siren m-ln�cmcdtbn- Areas 0,05k(D AA 934 Ac. b, V3 = ! 8 So x c c4 o Vc, 13 3 x . l 5' 1437 b - 15,:z W SRC b= 1G, 913 • u percri- iccll HOW) Use T L v rlit0.04- I acG.93, ► pp. V Jua IyVM43EM: l f �} A r a [� r r CHECKED BY: ITnntEY f MIMAS,�UKURO � MOCI�ATE/R inc. CIVIL AND STRUCTURAL ENGINEERS 13ATE: N1;ir. 11V-D-74 NOnK DESCRIPTION, Ilonolulu. Hawaii Ccn SHEET aF --9 _ PROJECT: . GUENT: C a nn(2.1 North Kong Hood Corr irol Froscc# Har n'l'lc unty (1) Horseshac fiend Sirenrn I d- Arcn5O( A: Sol Ac. Q- 1G50cf S -- zo*l, 68�3 = 01 (0,(7 x 0.C4o)Ab-133 �c,2 t7= 11 1 d' b = 13.91' use b= lGi f do/6 = 0.19G d ,, = 3.14' fps lGIAz' 1.�1 _o41 Usc. 7' RiL-3 d►'1 - �.141 App. D DESIGNED BY: H f -T m[Q� pp' }��[[jj �❑Q �j r r Q"� j� CHECKED SY� fTRnLE I / ��IM 1DVIMI RO 0 AHOCI, I UJ' VIC CIVIL AND STRUCTURAL ENGINEERS JOB Nt1mauf1l: DATE: MQr- I rlID-4 WORT{ DESCRIPTION: Honolulu, Hawaii SHEET "' OF � Open .— PR'OJECTCLIENT: Channel :North Kong Fiocd CoHrol 'lroleci �nwnli Courr q 90 Rorse,-Sho�-- beand Sircaryi of Momlatiahca Hwb w Area A = G9 5 AG t5o0 cf s 1 O °Ia $l ( I as do.23 fps K I c - I5o0 /l /z r 1 �5 dt/b = 0,38 d c = G . v 9' (.'. SuperCr ilcol How) free board - 4 V - 2,S8 G .sG' use71' lL 4�+z a =1oc Clcs V T 12.88` . I App , 0 DrSir.NEO BY: CHECKED BY: + 1 Al "LEY f MImIlBUKURO o moci Tee. inc. CIVIL AND STRUCTURAL ENGINEERS WOFIK DESCRIPTION; Honolulu, Hawaii C='r)c-1 I Ncr�h ron-a �lood Confr-ol to Culvert Crossing �it Hvj9 -M Ar-ergs Q � 9 A • 91 Ac. JOB NUMBER" DATE: Apr 15,M4 SHEET—!I—OF-3— CLIENT, }iawali CO�Anty cfs ¢-- Use- 0 4 -' .. ICI= S5n.04)l(81�'=�.�F�'}=0.0913 d n f b U. 20 V .a d�fb- .3a J JOB NUMBER DMGNED BY: H . I :y. CHECKED BY: WORK DESCRIPTION, ITAn(EY I MIIPABUKURU G WOCIATEI, VIC. CIVIL AND STRUCTURAL ENGINEERS Hanolulu, Hawaii PR Kcr th rl4 Flood Control DATE: M;o r 29. I7 + SHEET L OF—t— CLIENT: Deterrninc RLAnoff using l��w`�i i Coun I L tin a : -��r�c��rds I - Plate 4 Ta ble I . Runoff Ccx--f fiict&-ni C a . Vau kn of Mama ohaa HwL) (areas A �, E on1q) moknl of mnmaki�vn Hvq (including rheas B&F) Rai nfcall 1 nieni�� I-, & I, C:lr7f;1fraiian - slow!med• 0.10 Re.l ief - hi1Yrdl i n5 D. D5 0.03 Dev. 4pe -- 6 urb 0.2.(7 2 0.38 c ,1r lfrcffion - rued 0.01 #�eCie� •billy Yrallit� oo� leg Cover • poor good 0,0� D6-To ve • 11a -O gri.lres. 0.42 n. Areas A kE i 50 = 3.0 hches for 1-hi- rainfall A 19 2,5 %4 W %I it T, ` 3G ruin J,z = 3.9 S 7,o = 3.3 H - S%LW 7- 058 App. V i w DESIGNED BY: CHECKED BY: i 1 p1 tEY J. MIMPBUKURO G MOCIRTEX, InC. CIVIL AND STRUCTURAL ENGINEERS WORK DESCRIPTION: Honolulu, Hawaii y rci°° North Kona Flood Con r-of b. Areas 50 - 3.0 inches for I-hr rainfall LI„ .5 yy yi yr 41 • 7'1H1e�-e T=45maQ 1VO= 3.5 Z10 = 2.q5 c. Entire ll)rvmira;zge �z�sifl = .o i Inches for i-hr rairifal 0717 K Pi—ii wherc L-32,W0 & H�4igo Ta . 5 Ito ' 2.75 4, Runoff rs e-shae Be r)d St reo m @ ; i,, Mca►ma i � hoa � 1�1 - � QlG F 3.3 Y 2.G,4.1 - 91,2 cfs i . Moluaioa- Kcdua Read - klb.2,.0 Czt CI A s r(�sxGas)t,5S0 x I xSp2 ; 0.4Q�►$v L 802 QsO 32G.4 x 3..5 -- 114I cfs CHID 31G,4,t -1.5= 9 G 3 cfs J%.l{'f lvUmpCn. �DATE: Mnr 2q,M4 SHEET. of CLMNT� -52G. 4-1 4L ,. K4 ayj iva - KCeau hou jdd1f,, R,c od - A, f3, C F, D Q4CIA R ��` -r ° c.,s�k3 Q-so= 407.1,f 5.5 : 142.5 cis Qt 407.2 "2.95- 110! cfs App. a] 0 DESIGNED BY: H.1.Y ❑ 1 � J tmR �fr � ❑ { CHECKED BY; fTf {nIEY I 1 HIMAL1UJ♦UR© � WOCII 1TEI, IRC. CIVIL AND STRUCTURAL ENGINEERS WORK DESCRIPTION: Honolulu, Hawaii Rt draloc PPJ earth Kona Flood Cans rol b� Holualoa schcol str-eilm of,. i. Mococa4nhoa Sf recgm - 1�- C.L A = O.38 x l 140 Ic Z = 433.2. I 50' 433.2 x 395 = 1-7 It cfs Q10-= 432.2,c 3.3 = 1430 cfs i L' , Houaloct ECai(ua Road -- E, F. S-G JCL = !�� ;fix ti�la)x.ssa��l�) 42� = 521-3GI QIp= �521,3G x2`95= 1538 cfs .FUU Numut": DATE: IV 3r,210914 SHEET 2� DF-�— CLIENT: 'LLB. Kcauhou- KaiIua MIddle goad - �-,F,G & > CI A zF(?s''4a)+.58($Q-v'2f 3 1� 8 x'I 0,445v-13-78 1 _5-71.87I L t,6?8 0-50- 571,S7 x 3.5 - 2002 cfs Q10 = 5-71.27 x 295 : I(�97 r-fs c. Horseshoe en al caloa S pal reca sr i KC Aakini 4wq A 234.C): v.i�ry ,5" z34o--9 5,33 1 05 995.-!;3 x 3S cfs 293G cfs d. Sirwm tiMcrsecl1on muika cf Kuoki ni T A WZ5 u23+a1 + .58( 1 2-356 Q1003. 8 3.2 = 3513 cfs t = 1003. 8 x 2.`i5 = 2-°i �7 1 C.fs wall a 42bs b I ID�tB I t. Enure Droirya9c 13asln q+ Alsi Drive Ej, Oui{e+ Q I3c =-�.4�bxt35fi 585+3+~+11� 23�t=,�-22f�' 2634 C�5b -z� 11. 3 ' 3.-2 312E Cf 5 QIQ , 1164.17� '` "I5 * 320 z c�s App - D DESIGNED BY: JOB NUMBER; CHECKED BY: fTAntEy f fflIli ABUKtJiPO V l HOCIATEi. MC. DATE: CIVIL AND STRUCTURAL ENGINEERS 221 r. 1 GT I')74 WORK DESCRIPTION. Honolulu, IhWail i PR{}3EC�T: CLIENT: 1 � Kong � Coy r-ol -- - , uIverl c-r-ossings Q} c IN - 0,5g ¢q 1 x s-a-5218A3.5 T 195 Cl7 5 2.� 8< 2.� 5 z 15 G C f 5 a . Exist. E 6, 4, improved cha n n e 1 Cur 'Desi n C =3ncfs ns.0.c)+ S = I G '/- USSurne F 12. 2. cfs Use CQc.�t' : 2,1 DEjS� N�E(D BY: JOB NUMBER: CHECKED BY, J 1 snLE f MI1'IlFIBU UP0 G WOCIRTE1. Inc. DATE. CIVIL AND STRUCTURAL ENGINEERS A?r' 1, 1934 WORK DESCRIPTION: I'ianolUJU. Flawaii ` PRC3aEC7-' CILIEI4T- N orth )Cor-ycl lc�c� C<�r7�ra� DeerI' ] tnc, C 11 5 (Ur- X�5` I r'1 Open Ll H ricc4 C: p n -J 5 A. Hol unloo School il-eecayyl 1. axis}. ' ' l,-� r-oVcd chonnei I aWkci c4 Mcimnlohaa Our D��i r, = 2150 cfs r�= 0.0 S = �Lo/b assume , r� a cfs use, Q��F � 1850 2. R' x�` Doiculverf @) 1 c2malahoa 4wg. AsSurne HaRo, �, EHr-once-Conf rro` IC' Tgpp� ser'i . of P-Y, c c�r�nei _ (2 xL�)+(t+,0 6) = 7Z = 16 4 2.-F— - 24.9 4 jV v+ -q z z 2.gq �1 -X Box, b,9 Q f b = b8 n:-69%9 612cfs f aka; oar Moir olokon levy 30.0 S Alp. U DESIGNED BY; Joe NLMBER! H.1- - �jj� �j �ry p i rr inc. CHECKED BY: fTR LEY f IHIMABUKURO G FiffOCIATEX, Inc. DATE: CIVIL AND STRUCTURAL ENGINEERS Apr-. I i1914 WORK DE$CAWTiON: Honolulu. Hawaii �.. ` Hgdrou IiCs CLIENT: P R'dJ E C7: North Kcni Roof 'Con irol . F-xist ' 'F,�o7culverf C& Holgaloa - Kallua Rd. i b H n(j= ` g = 1.125 Q/b=?l a�b+9cfs App. 0 DESIGNED BY: 1 /�J CHECKED BY ,TAI/'� LEY Jr . fHIMFIBUKURV G AffOC1ATE1. inn. CIVIL AND MU+CTURAL ENGINEERS WORK DESCRIPTION: Ifonolulu, Hawaii F�r.�raultics PF#OJE l'; North i s FEond Caniroi JOB NUMBER: DATE: Apr. 1, I9 74 SHEET —�i— QF CLIENT: Hor-5e-shoc Dena Sfrcgm I. Exi5'- T n ci,-rar-,ne-1 Maukca of iAamoin 0cl iwy Durde gn r 1500 cfs n-0U4 ASsuync f B . of , I c 2-5 jjjF; �1,14 U se 0 , - 16 oc) cfs P.' a.13 . zxist 5,Y4' 5oxcu1ver# at Marnoiahoa.�Wq 0,�sume al �r ` �-nirctncc Conical Pi ate= 2 0 CIS -I HILT Q=rgar-fs 3 exist. 2- d" P Cul erf of Holunloa- KCINua Rd Hallow 1) r -5F square fi�qe vi l H eaci Wc(11 H/D ; 2,0 C "P = 250 cfs App. a N I DESIGNED BY: H .I .�(. CHOCKED BY: ITRmy x MIMPBUMA0 G# SffMIMI, [n[. CIVIL AND STRUCTURAL ENGINEERS WORK DESCRlPT10N: Honolulu, Hawaii t}t dru l�cs FRGJNorih �<onq Flood Control Cl Joe NUM9ER: DATE: Apr. 1,1974 SHEET�C7E CLIENT: Combined — Morseshoe. Send 4 Hdualna School StrItarnS I. Exist +2"cMf' ai Kuclkln" HWy Our Dcsln = �>400 cfs Hallow = q.5' D 3.5 Hob = 2.71 Heaciwal I Q = r 3C) cfs - f'1a#e, 2.1 2. xis�5x�..5' BaxCu1ve-rf cii A1ii Dr. our Design 6�- 57cv cfs Hu r e 20 6t low 5. Exist Chnonel n� jaceni -1okii KQi Subdivls10PI C)wr desig n Q i 3'70 0 cf s y'i = 6), o+ = $ °4° �- Cfs UjPzl P,t 1.52 Ap?. D Year Description 1973 Ordinance No. 586 appropriated $125,000 for the Kona Flood Control Project for FY 1973-1974. June, 1974 Draft EIS for North Kona Flood Control Project by Shimabukuro dated 6/1974, copy from Sinclair Library at UH-Manoa campus. Plates 2 (Drainage Basin & Hydrologic Data) & 5 (Existing and Proposed Improvements) of this document erroneously show Horseshoe Bend Ditch and Holualoa Ditch merging mauka of the then -existing Kuakini Highway location. August, 1974 Draft EIS for North Kona Flood Control Project by Shimabukuro dated 8/1974, copy from OEQC Library. This Report contains Responses from Agencies to the initial DEIS. Also, Appendix B contains Budget extracted from Master Plan Report; Description of Proposed Action; Probable Impact of the Proposed Action; Project Alternatives; Unavoidable Adverse Environmental Effects; Relationship Between Short Term Uses and Long -Term Productivity; and Irreversible and Irretrievable Commitments of Resources. December, 1974 Final EIS for Master Plan Report for North Kona Flood Control Project (Holualoa Drainage System) (Ordinance 586) by Shimabukuro dated December 1974, from DPW files. Plates 2 (Drainage Basin & Hydrologic Data) & 5 (Existing and Proposed Improvements) of this document erroneously show Horseshoe Bend Ditch and Holualoa Ditch merging mauka of the then - existing Kuakini Highway location. Plate 4 shows accurate channel congruence location makai of Kuakini Highway, and the text on Page 3 accurately portrays the existing congruence as below Kuakini Highway. The Drainage Calculations use Hawaii County Criteria. This Report is for use by the Governor; Mayor; County of Hawaii; and all other interested parties in their decision -making. The Report suggests a drainage system be developed in five Phases by government using ditches, culverts and diversion systems to control and collect sheet flow; deepening unlined streams; creating siltation and debris basins plus unlined channels across approx. The Phasing Plan was prioritized to ensure that adequate downstream improvements were available before upstream improvements were developed. 51 privately owned parcels to collect and direct the Holualoa drainage basin waters. The County will consider submitting an application to the U.S.D.A.'s Resource Conservation and Development Cost Sharing program for approval. If approved, the County may request for funding to implement this project. Undated EIS Approval Letter on State of Hawaii Executive Chambers letterhead signed by acting Governor George Ariyoshi provided on Page 15. Ariyoshi's term as Governor commenced December 3, 1974 so letter must have been signed December 15t or 2"d as Report is signed by him as "Acting" Governor. Note OEQC records report the DEIS as "NA" under "Determination", and NOT as "Approved" in their records. EXHIBIT B 10/14/76 Stream Lot 14 (TMK 3/7-6-21:18) and Stream Lot 15 (TMK 3/7-6-21:19) created as stream lots via Parcel Consolidation and Resubdivision #3863 by Dillingham and DIC (Carlsmith). 10/27/76 Stream Lot 14 deeded to County from Dillingham/DIC. 1979/1980 Land surrounding stream lots were deeded to Kalott by Dillingham/DIC. 10/26/82 Stream Lot 15 deeded to County from Dillingham/DIC. 12/84 North Kona Flood Plain Management Study done on 7 Kona drainageways by U.S. Soil Conservation Service in cooperation with DLNR; DPW; and Kona Soil and Water. Study recommended drainage improvements for Keopu; Hienaloli; Waiaha; and Kaumalumalu drainageways. Study recommended installing channels and culverts for the Holualoa and Horseshoe Bend drainageways per the Holualoa Drainage Study by Shimabukuro. This study established a 100-year design runoff of 1,260cfs for the Horseshoe Bend Stream and 1,480cfs for the Holualoa Stream. 1980-1984 Queen Kaahumanu Highway Extension built by the State Department of Transportation -Highways (S-DOT-H), which bisected both the Horseshoe Bend and the Holualoa ditches. S-DOT-H installed one culvert system under State-owned Queen Ka'ahumanu Extension for the Horseshoe Bend drainageway and one culvert system under State-owned Queen Ka'ahumanu Extension plus one under Kuakini Highway (State-owned portion) for the Holualoa drainageway. S-DOT-H used "SCS Hydrograph" 50-year design storm methodology (existing FEMA "Q") for hydrology analysis in their system designs. This resulted in 1,635cfs runoff quantity for the Horseshoe Bend culvert system. The County declined to install a culvert system for Horseshoe Bend drainageway under the County -owned portion of Kuakini Highway or under County -owned Kailua-Keauhou Road. 1983 DPW used "Peak Discharge vs Drainage Area" 100- year design storm methodology based on Plate 6 of Shimabukuro Report (North Kona Flood Control Project) for its system design of the planned drainage improvements. DPW's hydrology analysis resulted in 3,400cfs runoff quantity for the Holualoa Stream culvert system, over twice the estimate by the State's 50- year calculations. Increasing the State's methodology to design for a 100-year event (instead of the 50-year event used) would increase the runoff quantity to 1,880cfs, still only 55% of the County's calculations. By adding the runoff from Horseshoe Bend drainageway as planned by the North Kona Flood Control Project the combined flow would overwhelm the State's system and cause public safety issues for Queen Ka'ahumanu Highway; Kuakini Highway; and Alii Drive. Gamrex/DPW approached S-DOT-H asking them to increase the capacity of the Holualoa culvert systems under Queen Ka'ahumanu Highway and Kuakini Highway to accommodate the County's design criteria for the North Kona Flood Control Project. S-DOT-H declined to do so, and completed the system under their previous specifications. 1984 Gamrex designed the drainage system for their project based on the North Kona Flood Control Project, with the Holualoa and Horseshoe Bend drainageway convergence moved to mauka of the Queen Ka'ahumanu Extension versus makai of Kuakini Highway, and submitted plans for approval. S-DOT-H denied the convergence of the two drainageways mauka of Queen Ka'ahumanu. 1985-1988 DPW insisted on altering the convergence in accordance with the North Kona Flood Control Plan, and Gamrex/DPW commenced discussions with the landowner of a 12-acre parcel of land makai of Kuakini Highway where the actual existing convergence of the two drainageways occurs. They attempted to induce that landowner to cooperate in a drainage design that would allow the convergence to be relocated mauka of Queen Ka'ahumanu by obtaining S-DOH-H approval. They were unsuccessful. County obtained Drainage Easements over several Kalani Makai Increment II -A lots makai of the 12- acres which provided a drainage path for the converged drainageways. Also, drainage channel (Part of Phase II ofShimabukuro Plan) and siltation debris basin (Part of Phase I) were developed by Schuler Homes as part of Kamani Trees subdivision just makai of the Kalani Makai lots and were subsequently dedicated to the County as part of the North Kona Flood Control Plan. 1989 The landowner of the 12 acres went into foreclosure, and Gamrex acquired the 12-acres at auction at the behest of the County. Gamrex proceeded with archeological and topographical studies for design purposes. 1990 Revised drainage plans by The Keith Companies were submitted to S-DOT-H and DPW by Gamrex, said plans planning the convergence of Horseshoe Bend and Holualoa drainageways mauka of the Queen Ka'ahumanu Extension. Gamrex initiated discussions with S-DOT-H about relocation of approved access from Queen Ka'ahumanu Highway to the 70-acres as S-DOT-H had encroached into the existing approved access point with their Horseshoe Bend culvert improvements. Gamrex offered the County Office of Housing and Community Development their choice of either 10 acres of the makai land where the convergence exists or a portion of the 70 acres mauka of Queen Ka'ahumanu Highway to satisfy the affordable housing requirement. 1991 Plans by the Keith Companies used for Conditional Letter of Map Revision ("CLOMR") application from Gamrex to FEMA/DPW for drainage improvements in accordance with the North Kona Flood Control Project, with convergence planned mauka of Queen Ka'ahumanu Highway. FEMA requests drainage calcs for the existing County ditch at Kalani Makai and Kamani Trees makai of the 10-acre site with existing convergence. County unable to produce said calcs. 1992 Gamrex paid for the hydrologic calcs needed for the existing County ditch and provided them to FEMA. FEMA had concerns about S-DOT-H culvert system at Holualoa culvert being able to handle the combined flows of Holualoa and Horseshoe Bend ditches. Gamrex had Imata and Associates perform a drainage study dated August 7, 1992 which analysis used inlet control at the State-owned culverts, coupled with a planned installation of several concrete interceptor channels and flood control channels. This analysis concluded that, with the changes and additions to the improvements made, the existing State-owned culverts could safely carry the combined flow of Horseshoe Bend Stream and Holualoa Stream under Queen Ka'ahumanu Highway and Kuakini Highways. 1993 Gamrex further revised the drainage improvement plans and hired a third - party consulting firm to assist County in processing the CLOMR with FEMA. 1994 Processing of the CLOMR continued, now in Year 6 since Application. 1995 The CLOMR received FEMA approval in March of 1995, as Case #95-09-148R, seven years after submittal. Unfortunately, it was realized that a new Environmental Assessment needed to be done since the two stream lots were acquired by the County in 1976 and 1982, after the original FEIS was completed. This triggered State Chapter 343. A Draft Environmental Assessment ("DEA") was drafted and submitted by Gamrex. 1996 Trying to salvage the project, Gamrex Chairman Takashi Gamo moved his staff and offices to Honolulu, and became actively involved in the management and operations of the project. A Finding of No Significant Impact ("FONSI") was issued, and the Final Environmental Assessment ("FEA") was filed. This allowed the County stream lots to be improved. Unfortunately, it was recognized that the County did not own a small strip of land which was necessary to transmit the floodwaters from the 12-acre site makai of Kuakini Highway to the existing County -owned channels and siltation basin by Kalani Makai and Kamani Trees subdivisions. It was essential to own/control this land, so Gamrex/DPW started discussions with the two homeowners (Shell and Perez) that did own said land. More bad news arrived when SHPD informed Gamrex that the mauka boundary of the 70 acres planned for an interceptor channel to collect and direct sheet -flow was the site of an abandoned railroad right-of-way which SHPD decided needed to be preserved. Gamrex/DPW requested SHPD to re -consider such a preservation plan. 1997 Chairman Gamo died unexpectedly at the beginning of the year. 1998 SHPD gave their approval to use the RR ROW for an interceptor channel to collect sheet -flow at the mauka boundary of the project, eliminating that problem. Unfortunately, it was discovered the County had never completed the acquisition via dedication of the culvert under Kupuna Street; Kupuna Street itself; and the mauka portion of Royal Poinciana Street from the original developer (the guy who had been foreclosed on and lost his land to Gamrex). They approached him to cooperate with a conveyance of the properties but he refused to cooperate. 1999 Discussions with the two homeowners continued to make progress. No progress made with previous developer. 2000 The County passed Resolution No. 329-00, purportedly acquiring title to the roadways and culvert built by previous developer by using Hawaii Revised Statute Chapter 264-1 concerning abandoned roadways. 2001 Gamrex/County continued to negotiate with Sheff/Perez to acquire the required portion of TMI< 3/7-6-24:077. 2002 Agreement with Sheff/Perez finally reached for acquisition of the strip of land, and recorded at the Bureau. Unfortunately, this strip of land as well as the 12-acre parcel are in the Special management Permit ("SMA") area, so an SMA Application was put together and submitted for the improvements. 2003 Subdivision of the strip of land, portion of TMK 3/7-6-24:077, needed for the drainage channel, was completed. SMA Use Permit #4530 was issued, containing Conditions such as: 2) Construction of improvements to be completed within five years of SMA Permit date (5/5/03); 9) Planning Director may extend time for performance for a period not to exceed the original time frame. Relative to the planned drainage improvements Gamrex proceeded to work on 1) NPDES Permit; 2) US Army Corps of Engineers Section 410 Permit; 3) State Department of Health Section 401 Permit; 4) State DLNR Stream Permit; 5) County Grubbing; Grading; and Building Permits; and 6) SHPD clearances and permits. In addition, they worked with the 2 private landowners; DPW; CPD; OHCD; S-DOT-H; and three AOAO's trying to reach agreement on all the details of the flood control project. 2004 Gamrex submitted drainage master plan for the 70 acres to DPW in September. The two homeowners completed the cancellation of their CPR. Gamrex completed subdivision of Unit 213 in the large lot subdivision. 2005 Gamrex terminated their development team. No progress on drainage plan. 2006 Faulkner USA took over development of the project for new ownership "Kona Vistas LLC", a Joint Venture including Gamrex; Chase Berkely; and BIMAC companies. They completed the subdivision of Unit 4 of the large -lot subdivisions. 2007 Kona Vistas LLC completed the subdivision of Unit 3 of the large -lot subdivision. They also obtained Plan Approval for a 150-unit multi -family project on the 70 acres to be developed by Oceanside 1250. The Great Recession commenced. 2008 Kona Vistas LLC sold some residential lots. No progress on drainage system nor the 150-unit MFD project by Oceanside 1250. 2009 Kona Vistas LLC sold some residential lots. No progress on drainage system. The Plan Approval for the 150-unit MFD project by Oceanside 1250 expired. Oceanside 1250 terminated their involvement. 2010 Managing Partners in Kona Vistas LLC breached some Operating Agreement obligations, which led to litigation. No progress on drainage improvements. 2011 The litigation was resolved, with Chase Berkely and BIMAC exiting the Kona Vistas LLC team as well as the Project, leaving Gamrex as sole owner. They sold some residential lots, no progress on drainage improvements. 2012-2014 They sold some residential lots, no progress on drainage improvements. They started seeking a third party to develop the 70 acres MFD. 2015 Kona Vistas LLC sold the 70 acres zoned RM-5 plus some remnant residential and development lots to Kona Three LLC and KV3 LLC, respectively. The 12 acres had a Conveyance Document executed by Kona Vistas LLC in favor of the County at the insistence of County OHCD, which Deed was held in escrow by Title Guaranty Escrow Services pending completion of drainage improvements on the 12 acres ("Convergence Parcel"). OHCD stated in writing that the obtaining of a LOMR on the 12-acres would fulfill 100% of the Affordable Housing Obligations of the mauka lands (Kona Vistas + Royal Vistas). Since FEMA and the County were in the process of revising the FIRM Maps including Holualoa Stream, Kona Three was unable to proceed with a Conditional Letter of Map Revision Application until the new FIRM Maps were adopted. The planned drainage improvements included channelization of the Holualoa Stream within the Convergence Parcel, identified as a Phase I action in the Shimabukuro Report. 2016 Title Guaranty Escrow Services recorded the Deed to the County they were holding without notice to the County or to Kona Three LLC. Since the drainage improvements had not been completed, the County objected. The Office of Corporation Counsel notified Kona Three that the Conveyance as not acceptable, and Kona Three proceeded to work with the County to reverse it. 2017 The Conveyance of the Convergence Parcel was reversed, with the parcel being re -conveyed on 5-10-17 to a Kona Three -related entity since Kona Vistas LLC was in the process of dissolution. The new FIRM Maps were adopted by FEMA and the County on 9-29-17. The new FIRM maps doubled the "Q" (volume of floodwaters) in the Holualoa Stream, dramatically impacting the ability of the existing State -installed culverts under Queen Ka'ahumanu Highway and Kuakini Highway to handle any additional floodwaters, as proposed by the Shimabukuro Plan. Kona Three proceeded to prepare a CLOMR Application for the Convergence Parcel. 2018 Kona Three processed flora; faunal; archeological; and survey reports required for the CLOMR Application. OHCD continues to support the acquisition by OHCD/assignee of the Convergence Parcel once the drainage improvements are in place, to satisfy in full the Affordable housing requirement of the entire Project. 2019 Kona Three submits the CLOMR Application for the drainage improvements on the Convergence Parcel called for as Phase I improvements in the Shimabukuro Plan to FEMA and the County. Subsequently, on 10-31-2019, the County OHCD notifies Kona Three LLC that the Affordable Housing Agreement is officially terminated. 2020 Kona Three engineers opine that a possible solution to the recurrent flooding of existing residential homes makai of Kuakini Highway from Horseshoe Bend Stream floodwaters may be to install culverts under Kuakini Highway and possibly the (now abandoned) Kailua to Keauhou Road at the locations originally specified in the Shimabukuro Report, as these culverts were never installed in the 50 years since the Shimabukuro Report was filed. This would involve channelizing portions of properties owned by others, specifically TMK 3/7-6-24:29 (acquired by Jandoo Inc in 2019) and TMK 3/7-6-24:32 (owned by a Mike Kasser and Lynn Taube entity). 2022 FEMA and the County approved CLOMR Case No. 21-09-1757R for the channelization of Holualoa Stream and Horseshoe Bend Stream as well as convergence improvements on the Convergence Parcel. Kona Three starts work on possible solution to exciting flooding issues with their engineers and consultants. 2023 Meetings with Jandoo Inc and the Kasser/Taube Group occurred and were productive, with both property owners willing to work together with Kona Three and the County to address the flooding issues caused by the Horseshoe Bend Stream waters coming across the Keauhou-Kailua Road and Kuakini Highway. A Proposal was put together for the County to work on this project with the three landowners, as the County owns the roads and will need to be involved in both design and funding a new CLOMR to obtain approval for planned improvements (channels and culverts) necessary to stop the flooding, and sent to the County Mayor and DPW in July. Mayor Mitch Roth expressed support of the concept and indicated the County would follow-up. 2024 Kona Three and the other two landowners await a response from the County on the Proposal for a new CLOMR and drainage improvements. 'ay C4\ 1 Ary � � 0 Q _ - _• -.n .p�[ a.�,.:�. _,5t su �-�+ i•nM 1'�oa,. O• aan *�0.^. [f ^aB •n EXHIBIT CEXISTING ZONING -.-'a NO$VrH KONA OLQQ4 CONTROL RRO. EC-'• - [� __ ,... - ... •a -O"QiAL-DA CRAIMAI;E SYSTEM .. -n..: . . BTU A pipe culvert is grossly inadequate. Presently, runoff from severe storms overtop the embankments and flow along the shoulders before flowing across Kuakini Highway. Crossings on the new alignment should be constructed by the State. VI. CONSTRUCTION PHASING The recomr-ended construction phasing is shown on Plate 5, Appendix A. The construction phasing was developed on the following priorities: A. Adequate outlet to Lhe Ocean of the Drainage Basin Presently any runoff -producing storm causes flood waters to flow through the Shields -Pacific Concrete Products plant and over Al.ii Drive. The shallow channel constructed to, protect the Alii Kai Subdivision discharges directly toward the concrete plant. The continuation of this channel and the construction of a bridge on Alii Drive and an outlet to the ocean should have priority. R. Drainage Crossing on Kuakini Highway Kuakini Highway is the major highway in the basin and should have adequate protection from rain storm damage. The highway should be open under all weather conditions so emergencies can be responded to with dispatch. Construction of any improvements immediately above the highway would �. endanger the embankment and should await the construction of w the ;two crossings on. the existing Kuakini Highway. state - 12 - EXHIBIT E work on the new highway realignment should be uoordinated, with this master plan. C. Need to Contain Storage Flogs Within a well Defined Channel r The channels bulldozed by local residents can adequately contain the major flaws from ordinary storm through the built-up area along Mamalahoa Highway. Where the drainage ways are shallow and underdeveloped, the storm runoffs from intense local storms oftentimes overtop the banks and damage improvements and lands. This changing stream course results in the deposition of rocks, mud and debris, and breaches can roadways in places where no culverts exist. most of the overland flaw problems in the basin would be eliminated by containing the storm runoffs in well-defined channels. D. Provide Protection of Built-up Areas Along Mamalahoa Highwa Although the improvements constructed by the residents afford protection against the majority of storms, there is still a need for protection against the 50-year frequency storm. The existing channels should be improved so the entire system will be able to adequately and safely convey x J runoff from 50-year storms to the ocean. E. Provide for Orderly Construction construction of a gravity system should progress upstream. Generally, any improvements upstream should not be made until the downstream conditions can accommodate increased flows due to improvements upstream. Kona Vista Holding Company LLC 101 Hualalai Street Hilo, HI 96720 July 10, 2023 Mayor Mitch Roth County of Hawaii 25 Aupuni Street Hilo, HI 96720 Steve Pause, P.E., Director County of Hawaii Department of Public Works 101 Aupuni Street, Suite 7 Hilo, HI 96720 RE: North Kona Flood Control Project, Phases I & II Dear Mayor and Director, We write you as owners of vacant land consisting of approximately 10 acres in North Kona at TMK 3/7-6- 24:25 zoned RS-10, upon which we have obtained a CLOMR dated 1-10-2022, Case No. 21-09-1757R. This CLOMR is for channelization and culvert work at the junction of Holualoa Ditch and Horseshoe Bend Ditch, which merge on our subject property. These improvements were identified in the North Kona Flood Control Project by Shimabukuro & Associates dated 1971 (copy available in DPW-Eng office) as Phase I priority improvements, but were never built. Due to the willingness of two nearby landowners to co-operate, it is possible to also develop most of some additional flood control improvements identified as Phase II priority in the same Study. These improvements, if built in the Horseshoe Bend Ditch, would eliminate or minimize existing flood hazards affecting approximately 70 homes in the Alii Kai and Kuakini Makai subdivisions, as well as on -going flood hazards affecting County -owned Kuakini Highway and two commercial zoned properties mauka of Kuakini Highway. The County owns Kuakini Highway, over which the Horseshoe Bend floodwaters flow in flood events (such as the two events in September, 2017), and to efficiently mitigate the existing flood hazard, this flow should be channelized mauka of Kuakini Highway and transported underneath Kuakini Highway via culverts. Attached find aerial photos and diagrams showing existing and proposed flow patterns in this area, as well as the three privately -owned properties willing to work together on this possible solution. We are proposing a new CLOMR which would involve the two privately owned lots above ours as well as County -owned Kuakini Highway. We have a Proposal for said CLOMR forthcoming next week from MRConsulting in Phoenix, Arizona. They are qualified hydraulic engineers who excel in this area of civil work, and are a known quantity to the County and ourselves. EXHIBIT F-1 The purpose of tis Letter is to inform you of this possible solution to some of Kona's on -going flood problems, and to seek input from the County as to whether or not the County is interested in working with these three private property owners to seek a mutually agreeable solution that could benefit all involved, as well as the community at large. If the County is wiling to consider working with these landowners, please let me know at (808) 753-3167 or rchard@eastwestrealty.org and we would like have an initial meeting to discuss same at your offices in Hilo. Thank you very much for your attention and time. Aloha, Richard Wheelock, Member Kona Vista Holding Company LLC RAW: raw Enclosures CC: Lynne Taube w/enclosures Dave Knittle w/enclosures A f 11 r OPbSED CATCH BASIN NEW DITCH .�� EXISTING DITCH " . w i + lin ; NEW DITCH .'. � .*♦ rrr flf� ♦M♦ w t •.. ,t rrr '� 4 rrr 1 r r► ► r a �f r ,� ► �f � � Sadre SLymou jr • Sntanr'r.ai Gerais �4F r ► D mcipbox �9.4 L