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In January 1984, Greenhorne and O'Mara, Inc., prepared a study titled "Colorado River Flood Analysis at Grand Junction, Colorado" for Mesa County. The purpose of this study was to provide the city of Grand Junction and Mesa County hydrologic and hydraulic information to help manage flood warning, protection, evacuation and emergency response programs for conditions of high flow in the Colorado River near Grand Junction. Hydrology used in the study was developed by the Corps in 1976 for use in the flood hazard information report cited above. The scope of this study was a 5-1/2-mile study reach from the Redlands Parkway bridge, station 382.0, to east of the 5th street (Highway 50) bridge, station 387.5. The study identified three major levees in the study reach as existed in 1984 and proposed improvement plans to reduce flooding risks. In addition, the report summarized dam failure analyses performed by the state Engineer's office for dams upstream of Grand Junction and provided a plan for predicting and monitoring potential flood-inducing flows in the river. ' On June 2, 1984, a series of aerial photographs were flown by Nichols Associates, Inc., under contract for the Colorado Water Conservation Board. These photographs document flooding which took place adjacent to the Colorado River throughout Grand Junction and Mesa County during late May and early June 1984. In February 1985, Greenhorne and O'Mara, Inc. prepared a report tiled "Colorado River Hydraulic Analysis (Corn Lake to 34 Road) in Mesa County, Colorado." The purpose of the report was to present recommendations for additions and modifications to the existing dike system along a 3.2 mile reach of the Colorado River from 0.2 mile west of 32 Road to 34 Road. The hydrology used for this report was the Corps hydrology prepared in 1976 and used for the FEMA Flood Insurance study for Mesa County. The study presented the water surface profile for the study reach using post 1984 (post-flood) field information. The report proposed diking improvements for a 50-year level of flood protection. The reach of the channel within the scope of this study was from station 392.8 to about station 395. . . In May 1988, the Corps prepared a "Report on Inspection of Non-Federal Levees" for four levee sections along the Colorado River extending from about station 384 to 387. These four reports were filed with the Colorado Water Conservation Board in response to requests to inspect levees for determining eligibility for Federal rehabilitation assistance under Public Law 84-99. The purposes of the reports were to display information about the inspected levees and the results of comparing levee features with minimum Public Law 84-99 guidelines. The reports include text with descriptions, analyses, and conclusions; illustrations such as levee cross sections; inspection checklists; and soils reports about levee embankment material. 3