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PG 61-1a <br />CURRENT CHANNEL CONFIGURATION; CONVEYANCE <br />CAPACTI'Y CALCULATION FOR BOTTOM REACH <br />Assume: Channel has 2 foot flat bottom, 1:1 sides, and is 4 feet <br />in depth (this makes no allowance for the presence of the <br />original channel morphology above the incised portion of <br />the channel, but does utilize the depth of the original <br />channel). Soil/Cobble channel N=0.032 <br />1.49 <br />Q = AV = N R2/3 S1/2 A <br />Where N = Manning's co-efficient (0.032 in this instance) <br />A = [bd + zd2] <br />S = slope (decimal percent) <br />A bd + zd2 <br />R= b+ zd z + 1 R= b+ zd z + l <br />b = bottom width of channel <br />z = side slope of channel <br />d = depth of channel <br />• 1.49 <br />Q = 0.032 <br />Q = 46.56 <br />Q = 46.56 <br />2 4 + 1 4 2 2/3 <br />2 + (1)(4) (1) + 1 [0.06]12 [(2)(4) + (1)(4)2] <br />24 2/3 . <br />7.66 [0.2449] [24] <br />[3.13]2/3 [0.2449] [24] <br />Q = 46.56 [2.14] [0.2449] [24] <br />Q = 586 cfs <br />Calculated Q 586 cfs > currently required Q of 370 cfs <br /> <br /> <br />