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<br />The gages throughout the basin having 10 and more years of <br />record (see basin boundary map, Figure 1 and Table 1) were <br />analyzed to determine 10-, 50-, 100- and 500-year recurrence <br />interval discharges. For all these gages, the station skew <br />coefficients and standard deviations were calculated (Table <br /> <br />1) . <br /> <br />The ganes had a random spread of skew coefficients. An attempt <br />to relate skew coefficients to basin parameters produced <br />no significant correlation. Skew coefficients were then plotted <br />on a topographic ma? but no pattern was discernable. <br />The regional skew coefficient determined as an averag~Of the <br />station skew coefficients is ~0.52. This value agrees closely <br />with the regional value of -0.55 as recommended by WRC Bulletin <br />il17 for the Summit County region. This published regional value is adopted <br />for use in this study. <br /> <br />The 10-, 50-, 100-, and 500-year flood discharges were calculated <br />for each gage using the Log Pearson Type III distribution as <br />outlined in "Guidelines for Determining Flood Flow Frequency" <br />(Ref. 6). A summary of these discharges and other pertinent <br />gage information is shown in Table 1. <br /> <br />REGRESSION ANALYSIS <br />The gages with 10 or more years of record were considered in <br />developing regression equations for predicting 10-, 50-, 100-, <br />and 500-year flood discharges. Several parameters which may <br />have significant influence on the peak discharges were <br />investigated in this regression analysis. These variables <br />for the basin included the drainage a~ea, th~ average <br />basin elevations, the ~vera~e annual preci~itatiQD, !he <br />seasonal prec~eitat~on~ ~LOctober-April, May-September), <br />the basin slope, the main channel length, the basin orientatio~ <br />. _....... ....---l;Jili:!..~___........,_.."''''"-t <br />and the vegetation cover. (Refer to the Eagle County Hydrology <br />r ~~. ~- . ~ -) <br />Report for a description of these variables, Ref. 3). <br /> <br />-6- <br />