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separately for snowmelt events, as well as for rainfall events, The rainfall events were negligible in comparison to snowmelt events, i.e., the combined probability of occurrence equaling or exceeding a given discharge for snowmelt and rainfall events was very close to the probability of occurrence equal to or exceeding that discharge for the snowmelt event alone, The discharge-drainage area relationships developed for the 10-, 50-, 100-, and SOO-year recurrence-interval discharges for the snowmelt events provided a correlation coefficient of approximately 97 percent. A detailed description of this methodology is provided in a hydrology report prepared by the study contractor (Reference 6). The discharges for French Gulch were taken from the Breckenridge Flood Plain Information report (Reference 8), Peak discharge-drainage area relationships for streams studied in detail are shown in Table 1. 3.2 Hydraulic Analyses Analyses of the hydraulic characteristics of streams in the county were carried out to provide estimates of the elevations of floods of the selected recurrence intervals along each stream in the county. Users should be aware that flood elevations shown on the FIRM represent rounded whole-foot elevations and may not exactly reflect the elevations shown on the Flood Profiles or in the Floodway Data tables in the FIS report. Flood elevations shown on the FIRM are primarily intended for flood insurance rating purposes. For construction and/or floodplain management purposes, users are cautioned to use the flood elevation data presented in this FIS in conjunction with the data shown on the FIRM. Water-surface elevations of floods of the selected recurrence intervals for all detailed studies were computed through use of the U.S. Army Corps of Engineers HEC-2 step-backwater computer program (Reference 11). Cross sections for the backwater computations and flood plain delineation for Blue River were obtained from topographic maps (Reference 12) and field surveys (Reference 13), Cross sections on Willow Creek were taken from field surveys and topographic maps (Reference 14). Straight Creek cross sections were taken from field surveys and topographic maps (References 15 and 16). Tenmile Creek cross sections were obtained from field surveys and topographic maps (Reference 17). Cross sections on West Tenmile Creek were taken from field surveys and topographic maps (Reference 18), Digitized cross sections were used for analyzing the Snake River. These sections were taken from field surveys and topographic maps (Reference 19). Cross sections on Soda Creek were taken from field surveys and topographic maps (Reference 20). Cross sections on Meadow Creek were obtained by field surveys. Bridges, darns, and culverts on all the streams were measured to obtain elevation data and structural geometry. Locations of selected cross sections used in the hydraulic analyses are shown on the Flood Profiles (Exhibit 1). For stream segments for which a f100dway is computed (Section 4.2), selected cross section locations are also shown on the Flood Boundary and Floodway Map (Exhibit 2), 10