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maintain the system and would become part of the County's municipal system in perpetuity, Constructing a county-dedicable water system in a small,rural subdivision such as lid Place also opens up funding avenues through the USDA RUS Loan and Grant Program and fulfils the intent of the improvement district resolution established by residents and the Hawaii County Council. b. Design Criteria Alternatives 2 &3 -The water system required for either Alternative 2 or Alternative 3 would need to be designed in accordance with the County of Hawaii DWS standards found in the Water System Standards, State of Hawaii 2002, as amended. Road repair and traffic control would also be required in accordance with County of Hawaii Department of Public Works standards including Standard Specifications for Public Works Construction, September 1986 as amended. A breakdown of the water system design calculations for Alternatives 2& 3 is shown in the steps below: 1) Determine Design Flow Rate for Proposed System: The water source for either alternative would be DWS's upper level groundwater wells which would feed the proposed system by gravity. The average daily water usage per the Water System Standards is 400 gallons per day per home and the maximum daily usage is 600 gallons per day per home. Peak hour flow is five times the average daily flow. Flows for the 18 lot subdivision are estimated as follows: Average Daily Flow: 400 gpd x 18 lots=7,200 gpd Maximum Daily Demand: 600 gpd x 18 lots= 10,800 gpd or 7.5 gpm over a 24 hour period Peak Hour Demand: 5 x 7,200gpd=36,000 gpd or 25 gpm(round up to 100 gpm) Peak Hour Flow=100 gpm at 40 psi residual pressure Fire Flow= 1,000 gpm Design Flow=Peak Hour Flow Plus Fire Flow=1100 gpm at 20 psi residual pressure Pipelines are to be sized for maximum daily flow plus fire flow with a residual pressure of 20 psi at the critical fire hydrant and peak hour flow with a residual pressure of 40 psi. 2) Determine Static Pressure at critical points within the Proposed System: The Water System Standards require that static pressures in domestic service lines be a minimum of 43 psi (or 100 Ft. of head)and a maximum of 125 psi. Static pressures at critical points in the system were determined as follows: Elevation(Overflow) at Kalaoa Tank: 1,815 Feet Elevation at PRV in Akamai Street: 1,468 Feet Pressure setting of PRV in Akamai Street: 55psi Head(Ft.)to Pressure(psi) Conversion: 2.31 Ft./psi Elevation at point-of-connection in Aniani Street: 1,437 Feet(68 psi static pressure) Lowest Elevation within Iid Place ROW: +/-1,410 Feet(80 psi static pressure) Highest Elevation within lid Place ROW: +/-1,455 Feet(61 psi static pressure) 8