07/25/2007 Env Bd Packet - Laserfiche WebLink

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• • • (i) —Outten- - - - • - - - -and (iv) An outfall structure discharging to a wetland, public water or public water wetland must incorporate a stilling - basin, surge- basin, energy dissipater, placement of ungrouted natural rock riprap or other devieesfeature'to minimize disturbance and erosion of natural shoreline and bed resulting from stormwater discharges. (}v) All new residential, commercial, industrial and other habitable or non - habitable structures, and all stormwater basins, must be constructed so that the lowest floor elevations-are a- mini-mum-of two -feet above -he ^^+,coy o ens st titer i„T -and lowest entry elevations comply with the following table: (k) Within &landlocked bacincbasin, lowest floor elevations must be at least one foot above the surveyed basin overflow elevation. Where a structure is •r000sed below the runout elevation of a land- locked basin the low - floor elevation will be a minimum of two feet above the high water level as determined from an estimate of high water levels determined from the • f - 11- - r -h r r_infal - -• • •. ,- • -•. 11 will be used to derive a "normal" water elevation for the basin for the purpose of computing the 100 -year elevation. resulting -in—the- creation -of- -impervious surfaces must to first limit the low, of and second, -to- AnnitFate- runoff -w - -does ter- --ffain impervious areas -o- The- extent feasible coffering- site speck conditions. BMPs include -the- use -o€ vegetated cwales, -Rend outicts perched above levels, use ef infiltration systems, roof drainage-to- pervious areas, min-inium---e€ twenty percent pervious surface, usa areas, and -mini --ef the number- and-width-of-par-king- stalls -and use of deep- rested native- vegetation-, andnarrewer "rural section" roads. The goal of these BM Pa is 4G ineerporate practices-into the design - which are capable e+npewious surface -runoff from the Mpls St.Paul - mediae storm (0.34 inches) in seventy two hours. - will -- bee - calculated group classification and rate from the table below. DRAFT DOCUMENT 17 Regional Local Infiltration Basins Mottled Detention Elevations Basins & Soils Bottom MAC EOF EOF Wetlands 100 -vr EDE per borings Low 2-ft 1_-ft 00ft NA Q ft LIA NA 141 Floor Low IyA dA Lft LyA Zit 1 ft NA Entry. (k) Within &landlocked bacincbasin, lowest floor elevations must be at least one foot above the surveyed basin overflow elevation. Where a structure is •r000sed below the runout elevation of a land- locked basin the low - floor elevation will be a minimum of two feet above the high water level as determined from an estimate of high water levels determined from the • f - 11- - r -h r r_infal - -• • •. ,- • -•. 11 will be used to derive a "normal" water elevation for the basin for the purpose of computing the 100 -year elevation. resulting -in—the- creation -of- -impervious surfaces must to first limit the low, of and second, -to- AnnitFate- runoff -w - -does ter- --ffain impervious areas -o- The- extent feasible coffering- site speck conditions. BMPs include -the- use -o€ vegetated cwales, -Rend outicts perched above levels, use ef infiltration systems, roof drainage-to- pervious areas, min-inium---e€ twenty percent pervious surface, usa areas, and -mini --ef the number- and-width-of-par-king- stalls -and use of deep- rested native- vegetation-, andnarrewer "rural section" roads. The goal of these BM Pa is 4G ineerporate practices-into the design - which are capable e+npewious surface -runoff from the Mpls St.Paul - mediae storm (0.34 inches) in seventy two hours. - will -- bee - calculated group classification and rate from the table below. DRAFT DOCUMENT 17