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<br />RCWD Alternative Compliance Sequencing Report <br />City of St. Anthony Village PAGE 16 <br />WSB Project No. 1626-53 <br /> <br />Table 1: Required Volume Reduction based on RCWD Rules <br />Subwatershed <br />Drainage <br />area <br />(Acres) <br />Directly <br />connected <br />impervious <br />area within <br />ROW <br />(Acres) <br />RCWD volume <br />reduction <br />standard for <br />impervious <br />within ROW (0.8- <br />inches of runoff) <br />(ft3) <br />Annual volume <br />reduction <br />resulting from <br />RCWD <br />requirements <br />(ft3/year) <br />Silver Lake 325 26.3 76,375 1,362,648 <br />Ramsey County Ditch 3 372 39.2 113,837 2,036,987 <br />Mississippi River 53 7.1 20,618 367,918 <br />Previously Permitted Projects <br />Central Park Parking Lot (01-103) - - 666 11,888 <br />St. Anthony Schools (09-004) - - 2,195 39,181 <br />Silver Lake Road (08-016) - - 13,068* 233,264* <br />2009 Street & Utility Improvements <br />(08-070) - - 12,478* 222,732* <br />2010 Silver Lane Street & Utility <br />Improvements (10-002) - - 4,100* 73,185* <br />2011 Street & Utility Improvements <br />(10-086) - - 10,594* 189,103* <br />TOTAL 750 72.6 213,691 3,818,622 <br />*Note: Volume reduction requirement for these projects are also included in the subwatershed volume reduction calculation <br /> <br /> <br />C. Equivalent Pollutant Reduction Requirement for City Right of Way <br />The City of St. Anthony is unable to achieve the RCWD’s volume reduction <br />requirements using volume control BMPs. As a result, the City proposes to provide <br />equivalent water quality treatment to address the RCWD’s Rules. <br /> <br />In order to meet the RCWD’s water quality standards, the City of St. Anthony <br />Village would be required to reduce stormwater discharged from the City by <br />3,818,622 cubic feet per year. This volume-based standard of the RCWD has been <br />converted to a pollutant-based standard focusing primarily on total phosphorus (TP) <br />and also considering total suspended solids (TSS). Table 2 indicates the annual <br />volume reduction and equivalent pollutant reduction needed to meet the RCWD’s <br />water quality standard.