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There are several u.s. Geological Survey streamflow gaging stations on the Colorado River and its tributaries in the project area. The following is a list of the gages used in the hydrologic analysis. The gage locations are listed below: Gallin2 Station Period of Record Colorado River: near Cameo near Palisade near Fruita near Colorado-Utah State Line 1934 - 1985 1902 - 1933 1911 - 1923 1951 - 1985 Gunnison River: near Grand Junction (after Blue Mesa Dam) 1965 - 1985 The frequency analysis was performed using the log-Pearson Type III method, in accordance with criteria outlined in Bulletin l7B (Reference 6). The peak flow series that were analyzed represent primarily snowmelt floods which peak between late April and June. Following COE guidelines, a regional skew of zero was used for the Cameo gage. The results of the computations compared favorably with the results of the COE hydrology report. To determine if the discharges estimated by the COE downstream of Plateau Creek were appropriate to use at Palisade and points downstream, gaging station records at several points were examined. A study was made in order to compare flows at the State Line gage during the 1983 and 1984 snowmelt flood with flows computed by adding records of mean daily flows at the Cameo, Plateau Creek, and Gunnison-Grand Junction gages. (The Plateau Creek gage did not record any flows during 1984.) Peak discharge drainage-area relationships for the Colorado River are shown in Table 1. 3.2 Hydraulic Analyses Analyses of the hydraulic characteristics of flooding sources studied were carried out to provide estimates elevations of floods of the selected recurrence intervals. from of the the Locations of selected cross sections used in the hydraulic analyses are shown on the Flood Profiles (Exhibit 1). For stream segments for which a floodway was computed (Section 4.2), selected cross section locations are also shown on the Flood Insurance Rate Map (Exhibit 2). 6