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of Housing and Urban Develbpment, Federal Insurance Administ,ration. These flood boundaries have been delineated on I" = 2,000 ft. scale topographic maps. The approximate flood limits identified on the flood prone area maps prepared by the Geological Survey, are some- what wider than the actual flood plain area dete:rmined in ,this report. Other generalized evaluations on the potential extent of flooding within the community have been completed by the Cit:y Engi- neer for the City of Brush. No technical data is provided in the generalized evaluation, however these evaluations have been reviewed and considered in completing this st.udy. The findings of this study show the flood plain limits to be much wider and encompass more of the community than originally envisioned by the City Engi- neer and city officials. As no previous detailed studies have been completed on Beaver Creek near Brush, the study results presented herein are to be considered authoritative for purposes of flood plain information and flood plain management. Maps and Surveys The contour map on which the flood plain is delineated and the flood plain cross-sections used to calculate the water sur- face elevations were prepared by Bell Mappinsr Company under a separate contract with the Colorado Wat,er Conservation Board.. Two foot and five foot contour interval maps for the area north of and south of County Road DLD respectively w,=re prepared photogrammetrically from aerial photos taken in April, 1975.. The maps were compiled at a scale of 1" = 100', reduced for the flood plain delineation map to scales of 1" = 200' and 400' and meet or exceed National Map Accuracy Standards. The cross-sections used in the hydraulic analyses were also ob.tained by photogrammetric methods.. Permanent monuments shown on the base maps were established in the field during control surveys for t:he aerial mapping. The -.4-