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I I I I I I I I I I I I I I I I I I I In addition to the recorded data frequency statistics, the REGFREQ program also produces a set of adopted frequency statistics. The adopted frequency statistics are created using smoothing functions built into the program combined with the reconstituted frequency statistics to produce a smoothed set of frequency statistics for the family of curves. The REGFREQ adopted frequency statistics were used during the smoothing process as a guide, but not used outright. When the adopted statistics were plotted along with the gage data, the fit was not found to provide an adequate fit in all cases. Two additional guides used in the smoothing process were plotting standard deviation and skew values against the mean for the family of curves. These plots were used to aid in the creation of a consistent trend in the standard deviation and skew throughout the family of curves. This methodology is further described in Chapter 3 of "Hydrologic Frequency Analysis - EM-111 0-2-1415" (USACE, 1993). The smoothed statistics were estimated, plotted, and inspected for consistency and adjusted until a consistent set of curves was developed that described the raw data for each individual member curve of the family. The analytical distribution is only applicable for natural or unregulated peak flow data. The Taylor Reservoir on the Taylor River has influenced the flow records for the Taylor River and Gunnison River since construction in 1935 (Reaches 6,9, Taylor at A1mont, and Taylor below Taylor Park Reservoir). Therefore, it is necessary to remove the influence of the reservoir from the regulated data set to generate the unregulated flow data prior to performing the frequency analysis. Table 4.2.1 summarizes this information for all reaches. 10