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second could easily sweep an adult person off his feet, thus creating definite danger of injury or drowning. Rapidly rising and swiftly flowing floodwater may trap persons in homes that are ultimately destroyed or in vehicles that are ultimately submerged or floated. Isolation of areas by floodwaters could create hazards in terms of medical, fire, or law enforcement emergencies (Reference 2). 2.4 Flood Production Measures There are no existing or impending flood control structures in the study area or upstream of the study area which would tend to reduce the present flood hazard. Many small irrigation water storage facilities and farm stock ponds exist along Beaver Creek and within the Beaver Creek basin; however, these facilities have little, if any, impact on regulating or controlling the impact of major flood- waters downstream. 3.0 ENGINEERING METHOOS For the flooding sources studied by detailed methods in the community, standard hydrologic study methods were used to determine the flood hazard data requi red for thi s study. Flood events of a magni tude which are expected to be equaled or exceeded once on the average during any lO-, 50-, 100-, and 500-year period (recurrence interval) have been selected as having special significance for floodplain management and for flood insurance rates. These events, commonly termed the lO-, 50-, lOO-, and 500-year floods, have a lO-, 2-, 1-, and 0.2-percent chance, respecti vely, of being equalled or exceeded during any year. Al though the recurrence interval represents the long-term average period between floods of a specific magnitude, rare floods could occur at short intervals or even within the same year. The risk of experiencing a rare flood increases when periods greater than one year are considered. For example, the risk of having a flood which equals or exceeds the 100-year flood (l-percent chance of annual exceedence) in any 50-year period is approximately 40 percent (4 in 10), and, for any 90-year period, the risk increases to approximately 60 percent (6 in 10). The analyses reported herein reflect flooding potentials based on conditions existing in the community at the time of completion of this study. Maps and flood elevations will be amended periOdically to reflect future changes. 3.l Hydrologic Analyses Hydrologic analyses were carried out to establish the peak discharge-frequency relationship for each flooding source studied by detailed methods affecting the community. The hydrologic analysis was completed to estimate the peak discharge-frequency relationships for floods of lO-, 50-, lOO-, and 500-year recurrence intervals for Beaver Creek. The flood peak estimates were based on a statistical analysis of recorded stream 9