Laserfiche WebLink
EXECUTIVE SUMMARY <br /> <br />commercial, and infiltration/inflow (I/I)] projections were estimated based on population <br />projections and selected per capita and peaking factors. <br /> <br />Based on the method of projecting dry season flows, using actual historical data and <br />statistical analysis, the projected flows during the wettest dry season month at 2025 is less <br />than those projected using either the Oregon Department of Environmental Quality (DEQ) <br />guidelines or the limited data that was used in the 1997 Master Plan (Figure ES-l). <br /> <br /> Dry Season Maximum Month Flow <br /> Historical and Projected <br /> <br /> 80 <br /> <br /> 60 <br /> <br /> 4o <br /> <br /> ,-~ 30 <br /> <br /> 10 1997 Master Plan ~ Historical Data <br /> 0 .... ~ .... I .... ~ ' <br /> ~990 2000 2010 2020 <br /> Year <br /> <br /> F~URE ES-1 <br /> Flow Projec~ons <br /> MW~C Facil~ies Plan, Eugene-Spdngfield <br /> <br />A 2003-04 collection system modeling effort indicated that wet weather peak hour (WWPH) <br />flows generated in the collection system associated with the 5-year, 24-hour winter storm <br />event were comparable to those projected in the WWFMP. This is the flow that must be <br />treated under DEQ guidelines without resulting in sanitary sewer overflows (SSOs). The <br />best current estimate of the 2025 WWPH flow at the WPCF is 277 mgd. Based on this <br />projection, the WPCF faces a peak flow capacity deficit in a number of treatment process <br />areas, which are summarized in Figure ES-2. <br /> <br />Consistent with the WWFMP, the 2003-04 analysis showed that collection system capacity is <br />limited primarily at the Willakenzie pump station and WPCF influent screw pumps. <br />Additional local (i.e. city) collection system upgrades will be needed at several of the other <br />major local pump stations prior to 2025 to meet DEQ capacity requirements. The needs for <br />these additional improvements have been identified as part of this Facilities Plan but are the <br />responsibility of the individual cities. <br /> <br />MWMC_EXECSUM_REV4_2_.DOC ES-3 <br /> <br /> <br />