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Ditch 2 - 8% Chanel - Reclaimed Configuration <br />The following peak flow for Ditch 2 (8 %) was obtained from SedCad, page 14 -6 -121 <br />Location of Ditch 2 can be found on Exhibit 8C. <br />Flow <br />(cfs) <br />Ditch D2 24.6 <br />Manning's Equation <br />Flow In a Trapezoidal Channel <br />DEPTH D <br />0.82 <br />FEET <br />WIDTH W <br />3 <br />FEET <br />Slope S <br />0.08 <br />EXPRESS AS DECIMAL <br />Mannings "N" N <br />0.04 <br />EXPRESS AS DECIMAL <br />SIDE SLOPE X <br />1.5 <br />SLOPE = X:1 <br />AREA= (W *D) +(X *D)= <br />3.47 Feet2 <br />WETTED PERI METE R= (W) +2 *[((X *D)2 +D2)1/21 <br />5.96 Feet <br />R= AREA/WETTED PERIMETER <br />0.58 <br />V= (1.49 /N)'t(R21) *(SI12)= <br />Q =AXV= <br />Q REQUIRED - Peak Discharge <br />Riprap Sizing <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 = 0.40 feet <br />7.35 Ft/Sec <br />25.48 CFS <br />24.58 CFS <br />4.8 inches 12" In -Place <br />PR -5 14 -6 -125 (Rev. 05/12) <br />