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. PEAK FLOW CALCULATIONS <br />The following peak flow calculations were compiled with the computer program STORM <br />version 6.21. Details of the run-off calculations are shown on the following pages. <br /> 10-YR 25-YR <br /> 24 HR 24 HR <br /> Event Event <br />Pond B Drainage 17.05 22.63 <br />Pond C Drainage 30.62 40.19 <br />Drainage Area D 8.36 ---- <br />Drainage Area E 1.79 ---- <br />Flow calculations for the site ditches and culverts are <br />presented in following sections of this exhibit. <br />Spillway Pond B <br /> Pond B Emergency Spillway <br /> Manning's Equation <br /> Flow In a Trapezoidal Channel <br />• <br />DEPTH D 0.500 <br />WIDTH W 10.000 <br />Slope S 0.020 <br />Mannings "N" N 0.030 <br />SIDE SLOPE X 2.000 <br />AREA=(W*D)+(X*Dz)= <br />WETTED PERIMETER=(W)+2*[((X*D)z+Dz)vs] <br />R=AREA/WETTED PERIMETER <br /> <br />Q=AXV= <br />Q REQUIRED -Peak Discharge <br />Sediment Pond B <br />Riprap Sizing -Across top of Embankment <br />D50 =Size of Riprap <br />D50 = ((V X S^.17)/7.58))^2 <br />D50 = Diameter in feel <br />V =Velocity <br />S =Slope <br />D50 = 0.08 feet <br />PR-07 EXH-8 -6 <br />FEET <br />FEET <br />EXPRESS AS DECIMAL <br />EXPRESS AS DECIMAL <br />SLOPE = X:1 <br />5.50 Feet2 <br />12.24 Feet <br />0.45 <br />4.12 Ft/Sec <br />22.67 CFS <br />22.63 CFS <br />0.94 inches None Required <br />2/03 <br />