Recharge Calculations.pdfTerrence R. Reynolds, P.E.Name: 504 Easthampton Road Proj. No.: 123-0705Date: 10/9/23Location: Northampton, MA Computed by: TR "A" Soils "B" SoilsImpervious Area 5612 sf Impervious Area 0 sfRv = F x impervious area F 0.6 inches F 0.35 inchesA =Rv ÷ (D+KT) D=basin depth 0.2 ft "C" SoilsV=AxDK=Infiltration Rate 2.41 inches/hr Impervious Area 0 sfRv is the Required Recharge Volumet=time (2 hours for Rawls rates) 2 hrs (11-13) F 0.25 inchesF=Target Depth Factor. See Table 2.3.2.A is the minimum required surface area of the bottom of the infiltration structure Rv= F x Impervious areaV is the Storage Volume determined in accordance with the “Simple Dynamic” MethodRv= 281 cf D is a depth of the infiltration facility[1] A= Rv/(d+Kt)K is the saturated hydraulic conductivity.A= 466 sfT is the allowable drawdown during the peak of the storm (use 2 hours) V= A X DAp is the provided surface area of the bottom of the infiltration structureV= 93 cfVp is the provided storage for basinAp= 1785 sfVp= 357 cf OK[1] If the infiltration facility is a practice that uses stone or another media such as a dry well, only the void spaces must be considered. In those circumstances, use nd instead of d, where n is the percent porosity of the stone or other media.Storage Volume Sizing Calculation Worksheet (Simple Dynamic Method)