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<br />. <br /> <br />and runoff characteristics; selected a hydrology model which was applicable for basin <br />conditions; and computed flood frequency discharge values. <br /> <br />The rainfall values that were used for the analyses were as published in the National <br />Weather Service NOAA Atlas with no station adjustments. The 1D-year rainfall value was <br />adjusted to develop homogeneity among the rainfall runoff value. The value was adjusted <br />from 1.6 inches to 1.7 inches as presented in Table IV. <br /> <br />The discharge values of the 1992 CWCB hydrology study have been compared to the <br />regional curves for the USDA SCS Garfield County Study. When considering the watershed <br />hydrologic characteristics. the 1992 values appear to be reasonable and acceptable (See <br />Exhibit 5). A comparison of the March 1992 values with other studies show that the values <br />are also reasonable. This comparison is presented in Table V. <br /> <br /> TABLE V <br /> STUDY COMPARISON <br /> for <br />. Sulphur Creek Basin Hydrology <br />Flood SCS Merrick Merrick CWCB <br /> FrequenGY 1969 1976 1978 1992 <br /> (in years) (in cfs) (in cfs) (in cfs) (in cfs) <br /> lO-year 351 148 820 345 <br /> 25-year 439 xx xx 690 <br /> 50-year 615 297 1510 975 <br /> 100-year xx 513 1850 132S <br /> <br />The SOD-year discharge was determined by the extension of the frequency discharge <br />log plot curve as shown in Exhibit 4. No detention ponds or reservoirs were determined to <br />be applicable for the analysis. <br /> <br />RECOMMENDATION <br /> <br />. <br /> <br />The CWCB staff recommends that the flood discharge values as presented in Table <br />9 <br />