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Goal <br />Measure of Success <br />Minimum <br />Pollution <br />Managed/Year <br />A workshop for City and County staff will improve <br />Storm Drain Inlet System, <br />understanding of ordinances and codes and will <br />increase enforcement activities; <br />3o. Estimated Load Reductions and Method(s) (if applicable): <br />This WPP addresses a previous impairment for TDS, as well as several parameters of concern (TSS, <br />nutrients, oil and grease/hydrocarbons and bacteria) and has two overarching goals: <br />0 to prevent NPS pollution from increasing beyond current levels and to potentially reduce current <br />pollution in the watershed through the implementation of the Tasks described below; <br />0 to prevent predicted future NPS pollution attrributed to future development and changes in land <br />use through both the implementation of the Tasks desribed below and future efforts set forth in the <br />WPP. <br />Because the first few years of implementation are primarily preventative, no major water quality <br />improvements at the watershed scale are anticipated in the first 2 years. However, local results are expected <br />in the subbasin where BMPs will be installed. The table below shows expected minimum load reductions for <br />TSS and total phosphorus (TP), as well as % removal of bacteria from the two BMPs. These figures were <br />determined using accepted practices under WPP and WQPP pollution reduction calculation efforts. <br />Specific load reductions for selected BMPS will be estimated using acquired monitoring and other types of <br />data, literature values, and TCEQ EA protection manual BMP information. <br />Project <br />Recommended Water <br />Quality Treatment Measure <br />Minimum <br />Pollution <br />Managed/Year <br />Storm Drain Inlet System, <br />Bioretention/Detention <br />8o% TSS, <br />Pond, Rain <br />5o% bacteria <br />Downtown Stormwater <br />garden/treatment train or <br />5 lb TP <br />Retrofit <br />other retrofits (minimum 3 <br />acre drainage) <br />Stream bank restoration, <br />bank stabilization, <br />70% TSS, <br />Sessom Creek Stormwater <br />Detention Pond, Rain <br />garden/treatment train, <br />5o% bacteria <br />Retrofit/Stream Restoration <br />and/or other retrofit <br />1.25 lbs TP <br />(minimum i acre drainage) <br />The structural BMPs proposed in this project will affect water quality conditions in/near subbasins 10-13 <br />(Sessom Creek, City Parls, and Downtown) and accumulation points 7-8 (urban downtown, Sessom and <br />Spring Lalse). Table 1 below shows WPP polltuant reductions required for the Sessom Creels Watershed. <br />Table 1. Required Reductions in Instream Concentrations for Sessom Creels. <br />— 61.8 TCEQ=56.8 1.63 Target 19,537 TBD, refer to <br />8. Sessom Target A=57.3 3=0.03 ambient vs <br />Creek at Target B=57.8 stormwater <br />condition loads in <br />confluence WPP <br />Page 15 of 27 <br />