1202 SHUKSAN WAY 2018-01-01 MF Import

8.6 PUBLIC WATER SUPPLIES 8.6.1 T6teshold The analysis in the Warer System Plau projected the overall future peak-hour demand for the azea at 2.7 gpm/acre(approximately 4,000 gpa/day peak flow),and assumed fire flow requirements of approx+mately 3,500 gpm for commercial and industriaUmanufacturing uses. Based upon the proposed design of the water system, any development using more than 2.7 gpm/acre has the potential to affect water pressure on other sites. Additional analysis will be required for development proposals with a peak hour demand above 2.7 gpm/acre and/or a fire flow requirement of 3,500 gpm or greater. The additional analysis may be as simple as calculations completed by the Public VJorks Department prior to a pre-application meeting on a specific development proposal. The additional analysis m�st determine how the proposal's water demand will affect the entire�vater supply and distribution system. Projects with no additional major improvements needed and no adverse cumulative impacts on the water supply and distribution system are covered by this analysis. The 2.7 gpm/acre is an overall average peak hour demand assumed for planning in lazge arcas such as the study area. However, there�Nill undoubtedly be site-specific proposals with larger demand. For example, large irrigation systems cari exceed 50 gpm/acre demand. Other land uses with demands much lower than 2.7 gpm/acre, such as wazehouses, aze assumed to occur to offset the higher demand land uses, resulting in an overall azea wide average of 2.7 gpm/acre. The impacts of construction of the ne�v water line to service development west of Japanese Gulch were not covered in tize EIS. Additional SEPA analysis is required to review altemative routes for the line �vhich will minimize the impacts of the proposal. 8.6.3 Mitigntion Measures 1. Looped water mains may be required for some sites to meet fire tlow requirements and to protect �vater q�ality. Pressure reducing valves may be required when looped systems are constructed. (SEPA Public Services and Utilities Policies) 2. De��elopmen�s must construct improvements necessary to provide a water pressure of 40-80 psi under normal operating conditions as required by Public Works. (SEPA Public Services and Utilitics Policies) 3. Recycling of runoff water from bus or truck�vashing facilities is required. (SEPA Public Services and Utilities Policies) 4. Ne�v warer system facilities must avoid environmentally sensitive areas to the maximum extent possible. Where water lines must be constructed through em�iromnentally sensitive areas, best manaeement practices must be followed. (See the mitigation measures discussed in Section 4) (SEPA Earth, Water, and Plant and Mimal Policies) y �