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The U. S. Geological Survey (USGS) quadrangle maps show the ground topography east of Badger Creek to slope towards the City of Brush, approximately 4.5 miles east. As a result. there is concern for the possibility of floodwaters overtopping the channel banks in Badger Creek at the Burlington Northern Railroad and State Highway 6-34 crossings and for the floodwaters to travel east to Brush. Hydrologic calculations indicate the magnitude of the 100-year flood on Badger Creek to range between 25,000 (cubic feet per second) cfs and 30,000 cfs. Hydraulic computations show that the backwater effect created by both the railroad and highway embankments is sufficient to overtop the channel banks. However, the depth of water overtopping the channel banks at either location is not sufficient to move the excess flood waters over the 4.5 miles of cultivated fields and irrigation laterals and embankments and into Brush. Still, flooding can be expected to occur for some distance east of Badger Creek along the railroad and highway. The worst situation is along the railroad because of the higher embankment and no provisions for flows to overtop the embankment. Flooding has been experienced in Brush due to overflows from the Brush Lateral traversing through the west and north portions of the city. During the 1935 flood, much water WaS diverted from Bijou Creek into the Upper Platte and Beaver Canal and thus into the Brush Lateral, only to spill within the City of Brush, causing much damage and consternation. In 1965, floodwaters on Beaver Creek overtopped the Highway 6-34 bridge. Other bridges in the area were also washed out and closed for a period of 2 or 3 days until repairs could be made. The USGS estimated the peak discharge of the 1965 flood at the State Highway 71 cros sing south of Brush to be 24,300 cf s. Thi s flood was comparable to approximately a 25-year flood event. Figure 2 shows an aerial view of the approximate flood limits of the 1965 flood in the area southeast of Brush (Reference 3). The South Platte River in Morgan County generally flows easterly from the Weld-Morgan County line toward Fort Morgan where it gradually turns and flows in a northeasterly direction into Washington County. Throughout this reach the South Platte River flows in a relatively well defined channel. This channel is typically braided and is situated in a broad shallow valley ranging in width from about 1,500 feet to about 21,000 feet and is flanked by rolling plains. The streambed slope of the South Platte River in Morgan County is relatively uniform, generally ranging between 9 feet per mile and 5 feet per mile and averaging 6.5 feet per mile. The drainage area of the South Platte River in Morgan County varies considerably from the Weld-Morgan County line to the Washington- Morgan County I ine due mainly to the number of relatively large tributaries draining primarily the plains region located to the south of Morgan County. 6