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EVERETT 2044 <br />COMPREHENSIVE PLAN <br /> <br /> <br /> <br /> 6/17/2025 <br />COMPREHENSIVE PLAN <br />PUBLIC FACILITIES AND SERVICES ELEMENT <br /> Page 176 <br />Everett’s full distribution system, as well as various pressure zone groupings that reflect how zones are <br />interconnected through gravity storage and pumping. The results of the desktop analysis are <br />summarized below. <br />Source must be adequate to meet the projected maximum day demand (MDD) for each area being <br />evaluated. Three source areas were evaluated: <br />• From a system-wide perspective, there is a projected capacity deficiency of 13.0 MGD in 2040 <br />based on the Water Filtration Plan (WFP) capacity. <br />• The Evergreen Pump Station is projected to have a 3.2 MGD deficiency in 2040. <br />• The Casino Pump Station is projected to have adequate capacity through 2040. <br />For the storage analysis, the following components were evaluated for each of the reservoirs serving <br />Everett’s retail area: operational storage, equalizing storage, standby emergency storage, and fire <br />suppression storage. Results of the storage capacity analysis are: <br />• From a system-wide perspective, there is adequate storage capacity throughout the planning <br />period. <br />• When looking only at the pumped portion of the system (areas that have water pass through <br />the Evergreen Pump Station and/or the Casino Pump Station), a 1.7-million-gallon storage <br />deficiency is projected by 2040. <br />The projects identified to remedy source and storage deficiencies are included and scheduled in the <br />capital improvement plan (CIP) accordingly, to ensure that the projected system demand will be met <br />over the planning period. <br />A hydraulic analysis was conducted using the model to evaluate the adequacy of existing facilities to <br />provide current and future demand and fire flow under average and peak demand scenarios. The key <br />conclusions of the hydraulic analysis are: <br />• For peak hour demand conditions, the Everett distribution system was determined to be <br />adequate for the existing, 10-year, and 20-year demand conditions. <br />• Inadequate available fire flow was evident in certain locations throughout the system. Pipeline <br />improvements were identified for the existing system, 10-year, and 20-year planning horizons, <br />and placed into the CIP schedule. <br />Sanitary Sewer <br />The conveyance capacity of the system to convey flows to the WPCF was evaluated using the City H/H <br />model. The model contains the City’s combined and separated systems and is set up to capture both <br />systems’ response to rainfall. Two model scenarios were created to evaluate deficiencies – existing and <br />future (i.e. 20-year planning horizon). Simulation results for peak flow and peak hydraulic grade line at <br />system components were compared to a defined set of capacity criteria. New capital projects to <br />mitigate the deficiencies were determined for each scenario. A rainfall timeseries, referred to as the 15- <br />storm timeseries, was developed and used for model simulations. A version of the 15-storm timeseries <br />that incorporates climate change was developed for use in the future model scenario.