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<br />1) The gaging station statistics (mean, <br />deviation, and station skew) were computed. <br /> <br />standard <br /> <br />2) The data set was tested for both high and low outliers <br />(note that no low outliers were found in any of the data <br />sets analyzed). <br /> <br />3) The computed <br />regional skew taken <br />(Appendix 6). <br /> <br />station skew was wei9hted with the <br />from the map enclosed in Bulletin #17B <br /> <br />4) The peak lOa-year discharge was computed using the <br />weighted skew and the table of log-Pearson deviate values <br />found in appendix 3 of Bulletin #17B. <br /> <br />5) For comparison, the station skew was weighted with <br />regionalized skew values obtained from the earlier Corps <br />studies. These values were derived from other studies <br />performed by the Corps on similar basins in the region. The <br />peak lOa-year discharge was then calculat:ed using this <br />weighted skew. <br /> <br />6) Again for comparison, the peak lOa-year discharge was <br />computed by simply adopting the Corps' regional skew, <br /> <br />7) The ninety and fifty percent confidence intervals were <br />then computed using the mean and standard deviation, along <br />with the appropriate deviate values for the weighted skew <br />and data set, taken from Table 9-1 of Bulletin #17B. <br /> <br />8) The data set was then ex1:ended using historical <br />information (ref 4) discussed in both the 1973 and the 1981 <br />Corps reports and, in the case of the gage at: the bluffline, <br />some data was discarded due to assumed changes in the <br />watershed (the attenuating effects of the Halligan <br />Reservoir). See Appendix 5 for details of the data sets <br />used. The historical extension was accomplished by <br />considering the floods estimated by histod,cal information <br />to be the largest in the extended period. The rest of the <br />data was then weighted accordingly. The s1:ation statistics <br />were recomputed with the weighted data set, and steps 2 <br />through 7 were performed to produce the historically <br />weighted lOa-year discharges. <br /> <br />DISCUSSION <br /> <br />General <br /> <br />In conducting the analysis of the available information, WRC <br />Bulletin #17B was used as a reference wherever applicable, <br /> <br />Page ., <br />