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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />II <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />The criteria used in selecting dry, normal and wet years were based on the mean <br />and standard deviation of the seasonal precipitation from 1940 to 1984. Dry years <br />are defined as years in which the seasonal precipitation was less than the mean <br />minus 0.42 times the standard deviation. Likewise, wet years are defined as years <br />in which the seasonal precipitation was greater than the mean plus 0.42 times the <br />standard deviation, Normal years are years in which the seasonal precipitation was <br />between the limits set for dry and wet years, For a normal distribution, these <br />criteria will divide the sample set approximately into thirds, <br /> <br />If rainfall from April through October was less than 5,0 inches, the year was <br />classified for purposes of this study as a dry year, If rainfall from April through <br />October was more than 9,8 inches, the year was classified as wet. Years with <br />growing season rainfall between the limits established for dry and wet years were <br />classified as normal years, <br /> <br />From the series containing dry years, 1977 was selected as a typical dry year, <br />whereas, 1971 and 1984 were selected as typical normal and wet years from the <br />normal and wet year series respectively, For the typical dry, normal and wet year, <br />the monthly CIRi was calculated by determining the monthly CWR value and the <br />effective precipitation value for that year. In no case should the effective <br />precipitation exceed the CWR value. <br /> <br />Section 5: Shortages <br /> <br />Shortages in the basin were evaluated by comparing the total diverted water at the <br />head gate augmented by that portion of return flows directly reusable within the <br />service area with the computed minimum diversion requirements, Table III-3 <br />presents a more detailed computation of the shortages for a year similar to 1962 <br />which had been ranked as a Normal Flow Year and a Normal Rainfall Year. Table <br />III-3 also presents a summary of the results obtained for the 44-year period of <br />study. The results of this analysis were that, due to senior right locations, (1) <br />approximately 80 percent of all shortages in all the basin are concentrated in the <br />Upper Surface Creek Area, (2) there are no shortages during 'v\ay and June in years <br /> <br />III-I 6 <br />