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Dry Creek To define discharge frequency data for Dry Creek, several methods of analysis were used. A unit hydrograph involving rainfall-runoff relationships yielded the adopted results (Reference 19). Other methods included a regional analysis procedure, as explained in a report by the USGS (Reference 20), and a regional procedure relating peak discharges and drainage area for nearby gaging stations with similar hydrologic characteristics (Reference 19). Peak discharges for the 10-, 50-, 100-, and 500-year floods of streams in the study area and maximum known peak discharges for nearby streams having similar hydrologic characteristics are shown in Table 1. The J. C. Temple Reservoir was analyzed by routing the loo-year peak discharge developed from a regional relationship of peak discharges and drainage areas of nearby gaging stations. With this information and information from field inspection by geologists and engineers from the USBR, Grand Junction Office, it appears that the dam is now functionally sound and capable of safely passing a tOO-year flood discharge. Oak Creek A hydrologic analysis of flows in Oak Creek was performed for snowmelt and/or rainfall runoff over the basin. There are no active streamflow gage records for Oak Creek. A gage that fonnerly existed on Oak Creek for only 5 years (water years 1953 to 1957) was located 4.5 miles southwest of the Town of Oak Creek. The length of record of this gage was insufficient to be analyzed and provide meaningful results. The SCS unit hydrograph procedure (Reference 21) was then employed to determine the tOO-year peak streamflow. Significant parameters used with this method were a tOO-year, 24-hour rainfall of2.8 inches and an SCS curve number of 70. A tOO-year peak flow was computed using the assumed basin parameters and compared with the flow values of other streams in the region (Reference 2). Through this comparison, the loo-year peak flow was adjusted to reflect the runoff characteristics of the basin. The 10-year flood event was assumed to be the result of a snowmelt event. This value was obtained from a regional analysis of streams with acceptable gage records and similar characteristics. Peak discharge-drainage area relationships for Oak Creek are shown in Table 1. 3.2 Hydraulic Analyses Analyses of the hydraulic characteristics of flooding from the sources studied were carried out to provide estimates of the elevations of floods of the selected recurrence intervals.. Users should be aware that flood elevations shown on the Flood Insurance Rate Map (FIRM) represent rounded whole-foot elevations and may not exactly reflect the elevations shown on the Flood Profiles or in the Floodway Data Table in the FIS report. Flood elevations shown on the FIRM are primarily intended for flood 30