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to back up south of the D&RG railroad tracks nearly to the Bell Avenue bridge crossing of Oak Creek. Several low-lying residences would be flooded due to this backwater effect. Insufficient capacity of the crossings of Bell and Sharp Avenues, in conjunction with adjacent low-lying ground to the north of the creek, would cause flooding to some of the buildings in the downtown area. The baseball field area to the east of Moffat Avenue would be flooded due to insufficient capacity of the Moffat Avenue crossing. Oak Creek headwaters are located at the approximate elevation of 10,240 feet above mean sea level. The highest point in the basin is Sand Point, at 11,182 feet. Oak Creek, at the northern Town of Oak Creek boundary is at 7,390 feet. The length of Oak Creek from its headwaters to where it intersects Oak Creek's northern corporate limit is approximately 14.4 miles. The creek travels in a northeasterly direction for this entire distance. The drainage area of Oak Creek is 22.7 square miles. no major tributaries to Oak Creek. There are The study reach along Oak Creek covers the area within the Town of Oak Creek's corporate limits. The length of the study reach is approximately one mile. Oak Creek formerly meandered widely through the town. Over the years, it has been rerouted and straightened (Reference 2). 2.4 Flood Protection Measures At the present time, the Town of Oak Creek bas no flood protection measures within the corporate limits. 3.0 ENGINEERING METHODS For the flooding sources studied by detailed methods in the community, standard hydrologic and hydraulic study methods were used to determine the flood hazard data required for this study. Flood events of a magnitude which are expected to be equaled or exceeded once on the average during any 10- and 100-year period (recurrence interval) have been selected as having special significance for floodplain management and for flood insurance rates. These events, commonly termed the 10- and 100-year floods, have a 10 and 1 percent chance, respectively, of being equaled 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 gO-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 Flood 4