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The hydrologic analysis for the August 2003 Brush Creek LOMR was based on the effective information. For the Eagle River near the Towns of Minturn and Red Cliff, Taylor Creek, Brush Creek, and Turkey Creek and discharges for approximate study areas, discharge were determined using regression analyses based upon regional gage analyses. These regional analyses of streamflow data were completed assuming a log-Pearson Type ill distribution (Reference 10). The streamflow data were separated into snowmelt and rainfall peaks, and each type was analyzed separately. Fifteen stream gages located in Eagle County were analyzed. The length of record of these gages ranged from 6 years to 43 years. Drainage area-discharge curves were developed from these data for the 10-, 50-, 100-, and 500-year flood events. Snowmelt peaks were found to produce the flood peaks for larger drainage areas, and cloudbursts produced the peaks in smaller basins, generally less than 20 sq. mi. in area. Peak discharge-drainage area relationships for the Eagle River, Taylor Creek, Brush Creek, and Turkey Creek are shown in Table I. For Gore Creek and tributaries, flood frequency analyses of annual peak flow data were made for nine stream gages in the Gore Creek basin. It is unusual to have records available from that many stream gaging stations in a 102-square-mile drainage basin. Many of those stations now have records of more than 30 years in length. In addition, data for 11 gaging stations located in eastern Eagle County, but outside the Gore Creek basin, were analyzed to obtain a larger data sample and to better fill out the range of drainage areas for which data are needed. Previous flood frequency studies by GAl for the FIS used peak flow data through 1976. The current study used data through 1997, so 21 additional years of data were available for the current study. The orographic effects of mountain barriers have an effect on precipitation in the Gore Creek basin; this was a consideration in selecting stations to supplement the Gore Creek gages. The Piney and Eagle River peak flow data used in this study are all nearby and drain the western slope of the Gore Mountain Range. Care was taken to ensure the streams adopted for use in the regional study reflect reasonably similar orographic effects and runoff characteristics to the Gore Creek basin. The flood frequency analyses for individual stream gaging stations were performed using the computer program, FFFREAK, Version 1, that was developed by US VI est. The program was designed to run using peak annual discharge values contained in their HYDRODATA product. The program follows procedures recommended in Bulletin 17B (Referenqe 15). A plot of the standard deviations computed for these records versus their drainage areas resulted in a wide scatter of data points. No meaningful relationship was apparent. The average value of the standard deviation was just under 0.20, which is typical when snowmelt floods dominate frequency distributions. A generalized coefficient of skew of -0.3 was adopted for all stations based on the generalized skew map presented in Bulletin 17B (Reference 15). The average unadjusted coefficient of skew computed from the station record is -0.33, and the average adjusted skew'is -0.28, which are both very close to the -0.3 value that was adopted from the generalized skew map. Three events could produce runoff in the study area for Gore Creek and Tributaries (Reference 16): thunderstorms, general storms, and snowmelt. Floods could occur as a result of rapid snowmelt or rainfall alone, or a combination of those events. The seasonal distribution of peak flow data was reviewed for the 20 stream gaging stations to assist in defining the primary source of flooding. A total of 650 station years of record were examined, and about two-thirds (435) of the annual peak discharges occurred during June, 188 during May, and 24 during July. Only three of 18