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ii ..... .. COAL CREEK THROUGH THE CITY OF FLORENCE FREMONT COUNTY, COLORADO FLOODPLAIN DELINEATION STUDY SCOPE OF WORK Ms. Bet Lotosky, Flood Plain Management Services Program Manager, U.S. Army Corps of Engineers, Albuquerque District, met 19 July in Florence, Colorado, with Mr. John Liou, Federal Emergency Management Agency (FEMA), Region VIII; Mr. Tom Browning, Colorado Water Conservation Board; and Ms. Don Williams and Mr. Don Moore, city of Florence. Mr. Liou requested that the Albuquerque District, as study contractor, prepare a scope of work and a time-and-cost estimate for a floodplain delineation study for Coal Creek through the city of Florence. During the meeting, the study reach was discussed and identified, and the study reach is shown on the enclosed map and described below. The Colorado Water Conservation Board, the city of Florence, and Fremont County have agreed to share the cost required to provide the channel survey and cross-sectional data necessary to perform the hydraulic analysis for Coal Creek. The Coal Creek study reach will extend from the confluence with the Arkansas River to the upstream limit of the detailed study shown on the effective Flood Insurance Rate Map (FIRM), approximately two stream miles. The study will produce 100-year and 500-year floodplain delineations and 10-year, 50-year, 100-year, and 500-year flood profiles. The study contractor will plot the floodplains on copies of existing orthotopographic mapping incorporating two-foot contour intervals developed for the city of Florence in 1977. Floodplains for the reach of Coal Creek that extends outside of the limits of the city of Florence topographic mapping will be plotted on U.S. Geological Survey 7.5-minute topographic mapping with 20-foot contour intervals. The effective FIRM includes a floodway delineation; however, the floodway boundary will not change for the current study. Labor Category Item No. 3.1, Land Surveys, in the time-and-cost estimate reflects the time required for the study contractor to conduct a site visit, confer with the surveyor, and check the channel alignment and cross-sectional data provided. Labor Category Item No. 6.0, Base Map Material, reflects the time necessary to superimpose the survey data onto the base mapping for floodplain delineations. Item 8.0, Flood Insurance Study Report Preparation, indicates the time necessary to prepare a report describing the hydraulic analysis and the assumptions used in the analysis. Item F, Travel, indicates the per diem and travel cost necessary to conduct site visits to gather field data and to meet with local representatives to discuss the project and present results. Item D, Direct Material, is the cost to purchase U.S. Geological Survey topographic maps, and Item E, Special Equipment, is the cost necessary to reproduce the existing city of Florence topographic mapping. The study contractor previously created a hydrologic model for Coal Creek and developed the 10-, 50-, 100-, and 500-year peak discharges at selected concentration points. These discharges have been approved and accepted by the Colorado Water