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Ditch 5 - 9.25% Chanel - Reclaimed Configuration <br />The following peak flow for Ditch 5 (9.25 %) was obtained from SedCad, page 14 -6 -134 <br />Location of Ditch 5 can be found on Exhibit 8C. <br />Flow <br />(cfs) <br />Ditch D5 13.4 <br />Manning's Equation <br />Flow In a Trapezoidal Channel <br />DEPTH <br />D <br />0.6 <br />FEET <br />WIDTH <br />W <br />3 <br />FEET <br />Slope <br />S <br />0.0925 <br />EXPRESS AS DECIMAL <br />Mannings "N" <br />N <br />0.04 <br />EXPRESS AS DECIMAL <br />SIDE SLOPE <br />X <br />1.5 <br />SLOPE = X:1 <br />AREA= (W *D) +(X *D2)= <br />WETTED PERIMETER= (W) +2 *[((X *D)2 +D2)1'2j <br />R= AREANVETTED PERIMETER <br />V= (1.49 /N) *(RM) *(Sv2)= <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 = 0.35 feet <br />2.34 Feet2 <br />5.16 Feet <br />0.45 <br />6.68 Ft /Sec <br />15.64 CFS <br />13.35 CFS <br />4.2 inches Use 6" <br />PR -5 14-6 -139 (Rev. 05/12) <br />