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within the channel and along the overbanks. Although the area is not developed to any degree, the channel does flow under two main highways, State Highway 74 and State Highway 8, through two box culverts that should be able to pass the 100-year flood; however, the brush problem could sufficiently slow the floodwaters to the point of silt deposition inside the culverts. In fact, silt deposi- tion seems to have already occurred in the double 8-foot by 8- foot box culvert under State Highway 8 to the extent that the present area is approximately 75 percent of the original area. Many smaller tributaries to Bear Creek upstream from Morrison contribute relatively large peak flows to the Bear Creek flood plain and thus to Morrison. The highest recorded floods for Morrison occurred on July 24, 1896; July 7, 1933; and September 2 and 3, 1938. The peak flows estimated for the 1896 and 1933 floods above Mt. Vernon Creek are 8600 cubic feet per second (cfs) and 8110 cfs, respectively. The 1938 flood was caused by a cloudburst that centered on the divide between Mount Vernon and Bear Creeks near the top of Genesee Mountain. The highest peak for Bear Creek at Morrison, above Mount Vernon Creek, was only 6200 cfs; however, the peak for Mount Vernon Creek at Morrison was 9230 cfs (Reference 3). Other floods of lesser magnitude occurred on Bear Creek in 1934, 1957, 1965, and 1969 (Reference 4). Figures 2 through 5 depict estimated elevations on the Park Avenue, Canon Street, and Mount Vernon Creek Bridges. 2.4 Flood Protection Measures No flood protection measures have been provided immediately upstream of Morrison. Streams within Morrison have been channelized. Brick walls serving to streamline the flow comprise most of the channelization measures. However, most of the beneficial effects of the walls are nullified due to the adjacent growth of vegetation. These walls were built many years ago and have had little maintenance since that time. Removal of vegetation, sediment deposits, debris, and rocks from the floodways of Bear Creek, Mount Vernon Creek, and Bear Creek Tributary No. 7 would improve flood control, but the problem of the inadequate capacity of the State Highway 8 box culvert would remain. 3.0 ENGINEERING METHODS For the flooding sourceS studied in detail 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 equalled or exceeded once on the average during any 10-, 50-, 100-, or 500-year period (recurrence interval) have been selected as having special significance for flood plain management and for flood 5