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<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 />order) on Dolores Upper Mid. Bear Creek. Dolores Mid. West Dolores River, Dolores Lower, and <br /> <br />Lost Canyon Creek. F1o\\' 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 Stonn Distribution. Test runs of the 1% 2-day stoml sho\vcd that the 1% amounts for <br /> <br />the maximum 1-, 2-, 3- and 6.hour durations arc applicable to cloudburst-type stornlS rather than <br /> <br />general rainstorms. Those 1 % dural ion amounts were not considered in the final stonn <br /> <br />distributions. The t% 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 dislribulion 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 IIEC-1 Users Manual. page 13 (Reference 4-h). The reduction factors arc based on rainfall <br /> <br />duration and basin drainage area. The 2-day stonn totals arc 132% of the maximum 244hour <br /> <br />amounts (Table 12). The 48-hour specific and concurrent stonns over the subbasins \....crc <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-hourdurations arc 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 />