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<br />City of Everett <br />3rd Ave SE Water Quality Treatment Page 7 of 14 <br />· A review of the effectiveness of the existing facilities to meet current stormwater <br />standards will be developed and analyzed for overall performance. A similar <br />approach to the receiving water assessment process will be utilized. <br />· Basin flow control/WQ flows will be developed utilizing the Western Washington <br />Hydrologic Model (WWHM) and sizing assumptions utilizing representative models <br />based on impervious/total area. The modeling analysis will be utilized to understand <br />basin flows and WQ volumes to target to support initial sizing assumptions. <br />· Conveyance capacity of proposed pipes and downstream connection pipe will be <br />evaluated using Rational Method and Manning’s flow-flow analysis for in basin <br />sizing and WWHM for larger basins solutions. <br />· Treatment facility will provide a minimum Enhanced Treatment will be standard if <br />feasible unless otherwise evaluated. <br /> <br />Deliverables: <br />· Proposed locations with reference maps will be included in the Regional Facilities <br />Report. <br />· Outfall Catchment GIS data set <br />· Service area GIS data set <br />· Summary of primary pollutants and analysis of existing facilities effectiveness will be <br />included in the Regional Facilities Report. <br /> <br /> <br />Task 3.3: Prioritize regional facility locations. <br /> <br />The Consultant will prioritize proposed facility location based on the criteria established in Task <br />2.4. The criteria are anticipated to include: <br />· Catchment size/treated area <br />· Areas containing potentially high pollutant generating sources. <br />· Connectivity to impaired water bodies. <br />· Unmitigated impervious surfaces. <br />· Opportunities for shared use facilities <br />· Opportunities for design objectives that can incorporate other City plan <br />recommendations, such as the Parks PROS Plan, Surface Water Comprehensive Plan, and <br />SMAP. <br />City of Everett’s Responsibilities <br />· The City will select up to 10 sites to perform planning-level cost estimates.