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Peak Flow Calculations <br />The following peak flow calculations were compiled with SEDCAD. <br />Details of the run-off calculations are shown on the following pages. <br />25-YR <br />24 HR <br />Event <br />Pond F Drainage 51.2 <br />Flow calculations for the site ditches and culverts are <br />presented in following sections of this exhibit. <br />Spillway Pond F <br />Pond F Emergency Spillway <br />Manning's Equation <br />Flow In a Trapezoidal Channel <br />DEPTH D 0.9 FEET <br />WIDTH W 10 FEET <br />Slope S 0.02 EXPRESS AS DECIMAL <br />Mannings "N" N 0.03 EXPRESS AS DECIMAL <br />SIDE SLOPE X 2 SLOPE = X:1 <br />AREA=(W*D)+(X'DZ)= <br />WETTED PERIMETER=(W)+2•[((X•D)z+Dz)~n) <br />R=AREANVETTED PERIMETER <br />V=(1.49/N)'(Rvs).(Svz)= <br />Q=AXV= <br />Q REQUIRED -Peak Discharge <br />10.62 Feetz <br />14.02 Feet <br />0.76 <br />5.84 FUSec <br />62.0 CFS <br />51.2 CFS <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 feet <br />V =Velocity <br />S =Slope <br />D50 = 0.16 feet <br />TRY 4 <br />/1 PPRovEO <br />/ZD/~ <br />1.88 inches <br />Use Pit Run Material <br />App. B - 5 <br />