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<br />order) on Dolores Upper Mid, Bear Creek, Dolon:s Mid, West Dolores River, Dolores Lower, and <br /> <br />Lost Canyon Creek. Flow contribution from the three minor subbasins below the Dolores and <br /> <br />Lost Canyon Creek gages is minor and downstream of the study area of interest; no concurrent <br /> <br />storms were developed for them. <br /> <br />7.4 Storm Distribution. Test runs of the 1 % 2-day storm showed that the 1 % amounts for <br /> <br />the maximum 1-, 2-, 3- and 6-hour durations are applicable to cloudburst-type storms rather than <br /> <br />general rainstorms. Those 1 % duration amounts were not considered in the final storm <br /> <br />distributions. The 1 % 12-hour point rainfall total was distributed hourly using a ratio to the <br /> <br />maximum 12-hour period of the West Dolores River SPS distribution pattern from the 1976 study <br /> <br />(Appendix A, Table 4). Areal reduction factors were applied to the point rainfall amounts using <br /> <br />an equation from the National Weather Service Technical Paper 40, 1961. The equation is found <br /> <br />in the HEC-l Users Manual, page 13 (Reference 4-h). The reduction factors are based on rainfall <br /> <br />duration and basin drainage area. The 2-day stonn totals are 132% of the maximum 24-hour <br /> <br />amounts (Table 12). The 48-hour specific and concurrent storms over the subbasins were <br /> <br />distributed using the West Dolores River SPS pattern. The areally reduced rainfall amounts for <br /> <br />the West Fork centering for 1-,2-,3-,6-, 12-,24-, and 48-hour durations are listed on Table 13. <br /> <br />The hourly rainfall distributions used on the seven major subbasins for the West Fork centering <br /> <br />are tabulated in Appendix A, Table 6. <br /> <br />26 <br /> <br />. <br /> <br />e <br /> <br />-- <br />