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= 3400 ft. H = 210 ft. <br />X = 210 = 0.0617 <br />3400 <br />then LS = r 0.5 430(0.6176) + 0 3030.6176) + 0.431 <br />LS = 6.843 3.923 <br />7613) <br />LS = 4.05 <br />The control practice factor (CP) for the watershed of Pond 003 was <br />estimated to be 1.00 for fresh cultivated land with no conservation <br />treatment for a conservative approach (Barfield et al, 1981). <br />Next a stage- discharge relationship was determined for the modified <br />principal spillway. Pond 003 has an existing 36" CMP spillway and this <br />was left in place. But the inlet opening will be reduced to increase <br />detention time for proper storage and treatment of the 10 -year, 24 -hour <br />storm event. By trial and error a 6" CMP opening was determined to give <br />maximum detention time and still dewater the pond within a reasonable <br />amount of time (see Exhibit 7 -11 for detail of spillway). The <br />stage- discharge relationship for the 6" CMP principal spillway was <br />determined using Dodson & Associates, Inc's software for the analysis of <br />a pipe culvert and the results are listed in Table 3. <br />Lastly, Pond 003 basin geometry was calculated as follows (see Exhibit <br />7 -11). <br />Accumulated <br />Storage <br />Elevation <br />Stage (ft) <br />ac. -ft. <br />Description <br />6568 <br />0.00 <br />0.00 <br />Bottom of Pond <br />6577.10 <br />9.10 <br />5.13 <br />(2 +) MUSLE, and <br />Principal Spillway <br />Inlet Elevation <br />6577.38 <br />9.38 <br />5.38 <br />10 -year, 24 -hour Peak <br />Stage <br />6578.41 <br />10.41 <br />6:38 <br />(1)Ac. -ft. Pit Pumpage <br />6577.69 <br />9.69 <br />5.68 <br />25 -year, 24 -hour Peak <br />Stage <br />6580.00 <br />12.00 <br />7.99 <br />Emergency Spillway <br />Elevation <br />7 -6b -4 <br />Revised 8/27/86 <br />