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� . <br />Storm or Floodwater Runoff Channels in Colorado." In performing hydrology <br />studies the ENGINEER should assume that anv imgation canals will not <br />intercept stormwater runoff unless there is submitted written documentation of <br />historic acceptance, court ruling or similar information. The effects of dams and <br />other detention facilities on the hydrologic analysis shall be in conformance with <br />CWCB Rules and Regulations and shall be approved in writing by COtTNTY. <br />The report shall show the 100-year floodplain for "future watershed conditions" <br />in plan and profile and the 10-year water surface profile. Drawings shall be on <br />plan and profile mylars to be provided by COUNTY at a scale of 1:�000 with <br />two-foot contours. The lunits of the 100-year floodway shall be defined in <br />tabular form referenced to cross-sections on a separate map. The floodways <br />shall be based on a total increase of not more than .2� meters in the computed <br />energy grade line due to an approaunately equal reduction in conveyance on both <br />sides of the floodplain, or other criteria which COUNTY, in cooperation with <br />LOCAL SPONSORS, specifies or ENGINEER recommends and COLTNIY <br />approves. <br />Floodway data will be keyed to cross-section stationing and elevations. When <br />the flows are contained within the defined channel, floodwav data will not be <br />needed, but the condition should be so indicated in the tabulation. The report <br />shall include, but not be limited to the following: <br />a. A summary of pertinent data or information obtained from COUNTY, <br />USBUREC, the Canal operators, Colorado Department of Transportation, <br />Corps of Engineers, U.S. Geological Survey, Soil Conservation Service, <br />State Engineer, various utility departments and others. <br />b. Identification of major watershed features. <br />c. History of stream relative to flooding, inventory of any available <br />streamflow data from the watersheds and adjacent watersheds, and ' <br />description of various hazards associated with the areas in or near the <br />100-year floodplain. <br />d. Typical design hydrographs for the watershed and each sub-�vatershed and <br />hydrologic information in terms of rainfall data, coefficients, land uses <br />(imperviousness), slopes flood flows vs. channel staxioning (discharge <br />profile), rainfall abstractions, watershed areas, etc. for the 10-, 2�- and <br />100-vear recurrence interval frequencies under "future watershed <br />