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Utilizing the peak 100-year diversion flow of 2,660 cfs, an analysis was undertaken to track the street-by-street flow from the point of diversion to its outlet. For this analysis, Manning's equation was used with average street slopes obtained from a detailed field survey. The Manning's "nil value used in the calculations was chosen as 0.025, which is a composite value for a highly urban area where the street flow paths are open. The sections used in the calculations were rectangular and covered only the street (building-to-building) areas. Where ponding areas were encountered, critical weir sections were outlined from the survey and the total downtown flooding areas were developed (Reference 2). The analysis of the 500-year overflow in the west bank through the downtown area was adopted from the previous study by the COE (Reference 1). The depth of the 100-year flood through the outlet section of Lake Minnequa was determined to be 1.5 feet from the lake stage-discharge curve. As the flow continued into the street system, the depth of flooding decreased as the flood plain spread out and, at the average depth of flooding, became 1.0 foot or less. Thus, it was classified as a Zone B shallow 100-year flood plain as determined from rough typical street capacity calculations. Because the flooded area has a free outfall across Interstate Highway 25 to the Arkansas River, no major ponding problems were encountered. The hydraulic analysis of the Bonforte Boulevard Area revealed that the average depth of flooding for the 100-year flood would be less than 1 foot. Approximate 100-year flood elevations for the Arkansas River and University Park Tributary were determined by the HEC-2 program (Reference 15). Approximate elevations for Dry Creek (East) downstream of a point approximately 600 feet downstream of Qakshire Lane were determined by the HEC-2 program (Reference 15). Approximate elevations upstream of this area were determined from normal-depth calculations. Profile base lines were used to establish the relative distances shown an the profiles for the Arkansas River (downstream of the Burlington Northern Railroad), Fountain Creek, and Fountain Creek East Bank Overflow. These profile base lines are shown and identi- fied on the maps. All elevations are referenced to the National Geodetic Vertical Datum (NGVD) of 1929. The City of Pueblo Datum used was converted to NGVD datum by subtracting 13.6 feet from the city datum. Elevation reference marks used in this study are shown on the maps. 20