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The Colorado Water Conservation Board made no designations regarding the floodplain for the City of Las Animas. Prior to construction of the Las Arlimas Flood Control Project, the Corps prepared drawings, dated July 30, 1976, of plans for construction of levees and appurtenant facilities. These drawings included the general plan and the plan and profile for the levees and structures. No water surface profiles or floodplain maps were included with these drawing". After the Project was completed in 1918, the COIpS prepared an Inspection Date Document showing the completion date, the sponsor acceptance date, and Project inspection dates. In February 1979, the Corps prepared the Operation and Maintenance Manual (O&M Manual) for the Las Animas Flood Control Project. This document provides irrfonnation about the Project, briefly describes major Project facilities, and presents basic instructions for proper operation and maintenance of the Project and faci.litie,;, The Federal Emergency Management Agency (FEMA) acknowledged the Project's protection in a letter dated June 26, 1985, to the City of Las Animas. FEMA staled in the letter that they had determined that no Special Flood Hazard Areas existed at that t:lme within the corporate limits of the City and that no map would be published. Conversion to the Regular Program of the National Flood Insurance Program was effective July 10, 1985. Aggradation of the Arkansas River During public hearings held by the Corps in 1944 and 1950, statements were made relating an increasingly serious flood threat at Las Animas caused by heavy plant growth in the riverbed which retarded flows and resulted in deposition of silt and decreased channel capacity. Channel straightening and installation of steel jetties were suggested as corrective measures. At a meeting in 1959 the Arkansas River Conservancy District pointed out that despite the channel work accomplished during the past 10 years, the Arkansas River channel had continued to aggrade. It was their opinion that channeli7.ation alone would not solve the problem and that levees also would be required to provide a permanent solution. A preliminary plan of improvement for flood control was discussed at a meeting in 1962. As previously indicated in this report the Corps completed the Las Anirnas Flood Control Project in 1978. Aggradation of the streambed of the Arkansas River continues to be a major problem from Pueblo to the Colorado-Kansas state line. Two significant effects are apparent on the Las Animas Flood Control Project. The first is the reduction of channel c~pacity in the Arkansas River. This reduction is of particular concern in the 1 mile reach of the river beginning upstream of the U.S. Highway 50 bridge north of Las Animas and extending downstwam past the AT &SF Railroad bridge northeast of Las Anima~. The narrow point of the floodway is also at this point which further compounds 4