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<br />thus derived liaS used as the standard project stonn rainfall. An initial <br /> <br />loss rate of 1.00 inch and an average hourly loss of O. 2S inch \Vere used <br /> <br />to detennine the rainfall excess. The rainfall excess Has applied to the <br /> <br /> <br />uni t hydrograph sho\Vn on plate 1 and resulted in a peak discharge of <br /> <br /> <br />41,000 c.f.s. for the standard project flood. The volume for the standard <br /> <br /> <br />project flood would be 46,800 acre-feet. This is equivalent to 7.2 inches <br /> <br /> <br />of runoff from the 122 square miles of drainage area. Data pertinent to <br /> <br /> <br />the standard project flood are shown on plate 1. A comparison of the <br /> <br /> <br />standard project flood peak with the curve of maximum experi.enced peak <br /> <br /> <br />discharges for the Arkansas River-John Hartin Dam to lial:out Creek is shOlm <br /> <br /> <br />on plate 2. <br />18. Flood Frequencies. There arc no stream gaging rec.ords for \';01 f <br />Creek at Granada. The peak frequency curve was computed from frequency <br />development curves. A study was conducted to detennine regional ized <br /> <br />peak frequency development curves for ungaged streams in the Arkansas <br /> <br />River basin from John Hartin Dam to Great Bend, Kansas. Gaged streams <br /> <br /> <br />in the Arkansas River basin Ivere studied and peak frequency curves were <br /> <br /> <br />developed from flow records. The 2 and 20 percent recurrence interval <br /> <br /> <br />flows for each station were determined from the frequencies wi thout <br /> <br />adjustment for likeliness and these values were divided by the peaks of <br /> <br />the unit hydrographs for the areas to obtain ratios of Q/QUIIG. These <br />were plotted against drainage area as shown on plate 3. <br /> <br />19. Gaged streamflow records for areas adjacent to the study area <br /> <br />8 <br />