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This work was completed in September 1987. The second phase, consisted 'of a hydraulic re-analysis for the reach of the South Platte River through the Littleton Flood Plain Park, located immediately upstream of the CaE's channel improvement project. This re-analysis was completed in Novem.ber 19.87 by Michael Baker, Jr., Inc., Technical Evaluation Contractor for FEMA. The hydrologic data for both phases were obtaine.d from the technical report, entitled "South Platte River Hydrologic Study, Chatfield Dam to Sand Creek," dated May 1983, and developed by Merrick and Associates, Inc., under contract to UDFeD (Reference 1). 1.3 Coordination The Director of Community Services supplied zoning and corporate boundary maps for potential flooding areas. The City Engineer and Director of Public Works supplied city benchmark data, details of storm sewers, 2-foot contour mapping of Slaughterhouse Gulch, and channel improvement plans. Several conferences were held with the city staff. The COE, Omaha District" supplied base maps, hydrologic data, and information on Chatfield Dam for the study reach of the South Platte River. In addition, several conferences were held with the CaE, Omaha District Office. The U. s. Geological Survey (USGS) supplied historical flow information. (References 3, 4, and 5). At a joint meeting with the UDFCD, FEMA, and Gingery & Associates, Inc., the study reaches were defined, as was the methodology to be used in the study. An additional meeting was held in Washington, D. C., to further clarify the purpose of the study and methods used for floodplain delineation. The UDFCD supplied contour maps at 2- foot intervals on Big Dry Creek, along with the interim June 1974 report, entitled "Major Drainageway Master Plan - Big Dry Creek" (Reference 6). Several other agencies and individuals were contacted for background information, including the Colorado Water Conservation Board, Arapahoe County, and the U.S. Soil Conservation Service. A public hearing was held by the Planning Commission of Littleton in which the Consultation Coordination Officer (ceo) and the engineering consultant explained to the commission and citizens the purpose of flood insurance and the technical methods used to develop the maps presented. On February 10, 1976, the final CCO meeting was held, all previous problems having since been resolved. In attendance were representatives from FEMA, the study contractor, and the city. FEMA authorized a restudy of selected watercourses in Arapahoe County and Incorporated Areas in December 1985 (Reference 2). Prior to the restudy, a meeting was held with the Arapahoe County Engineering Department and UDFeD in early April 1984 to define study reaches. No reaches were identified at this meeting. The 2