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<br />Hydraulic analyses were performed using normal depth calculations to estimate peak flood flows <br />for the event. Peak flows were computed for five separate cross-sections on 4 separate streams. <br />The average flow velocities at each of the 5 locations ranged from 4.5 feet per second to 12.5 <br />feet per second, and the Froude numbers fanged from 0.4 to 1.2. The peak discharge estimates <br />are presented in Table 1 below. <br /> <br />Table 1 <br />Peak Discharge Estimates for Flash Flood of July 26, 1999 <br /> <br /> <br /> Longitude <br />Middle 4,000' uls of WI06 18.088' <br />Creek Cabin Draw <br />Middle Just dls of 51 2,800 9.3 8,240 N38 11.858' W106 18.192' <br />Creek Cabin Draw <br />Ward 500' uls of 2.8 1,800 12.5 8,600 N38 11.940' W10621.893' <br />Gulch Jacks Creek <br />Jacks 1 mile dls of 30 1,350 7.5 8,200 N38 10.765' W10619.434' <br />Creek Cross Creek <br />Saguache At gage just 595 1,250 4.2 8,030 N3809.80' W10617.40' <br />Creek dls of Middle <br /> Creek <br /> <br />Note: some of the discharge points in the upper watershed are higher than downstream locations due to attenuation <br />and significant ponding behind county roads and debris dams. The flow into Saguache Creek was reduced by the <br />impoundment/weir created by Highway 114. <br /> <br />Gage records are available for the Saguache Creek gaging station located just downstream of the <br />Middle Creek confluence. The published period of record is from .1911 through 1994, with data <br />missing from 1983 through 1990. The 1999 peak flow at the gage (1,250 cfs, preliminary) now <br />represents the flood of record, which supersedes the previous flood of record (756 cfs) on May 2, <br />1928. The CWCB performed a statistical flood frequency analysis of the gage data (aru:mal peak <br />flows) using a "without the 1999 peak" approach and a "with the 1999 peak" approach. The <br />flood frequency data computed for the Saguache Creek gage is presented in Table 3 below. <br /> <br />Table 3 <br />Flood Frequency Data <br />Saguache Creek Gage <br /> <br /> <br />Peak Discharge'( cfs) <br />"with 1999 peak" <br />1780 <br />1490 <br />1290 <br />1100 <br />693 <br /> <br />2 <br />