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<br />Discharges for FEMA <br /> <br /> <br /> <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />'I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />weighted skew is closer to the station skew than 17A. Using the <br />extended data base (through 1983) increases the flow about 2 <br />percent. Using 17B and the extended data base (648 cfs) results <br />in a decrease of about 5 percent from the 100-year peak flow used <br />by Worrall (679 cfs). Complete output from the statistical <br />analysis is shown in Exhibit 2. The analysis was done using an <br />in-house JFSA computer program developed for the WANG 2200. <br /> <br />Discussion <br /> <br />We recommend using the Worrall regressions for the following <br />reasons: Although the Worrall study was completed before the <br />Water Resources Council published Bulletin 17B, the most current <br />version of their recommended log-Pearson Type III analysis, the <br />differences are minor. Adding the diversion flows to the gage <br />records is a conservative assumption. The Worrall flow numbers <br />agree well with other studies in the Fraser basin. In addition, <br />the Worrall flow estimates have been widely used by developers in <br />the last three years. <br /> <br />The Worrall regressions were used to develop peak flow <br />discharges for the present FEMA study (Tables 6 and 7). Where a <br />discharge is required between these stations, it will be assumed <br />to increase linearly along the stream. <br /> <br />JFSA 81250 <br />D11/17 <br /> <br />-7- <br /> <br />