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<br />. <br /> <br />affected watershed (actual wildfire impacts shall be evaluated on a case-by-case basis). <br />Interim flood advisory maps, based on burned watershed conditions, shall be produced <br />at the request of the local governing authority or by Board initiative. The interim <br />floodplain maps shall be produced using CWCB Flood Response Program funding <br />using post-wildfire hydrology that shows increased nmoff from hydrophobic soils and <br />lack of vegetation. The post-wildfire maps shall be evaluated every 3 to 5 years to <br />assess the need for further revision based on watershed recovery, forest regrowth, and <br />other factors. <br />c. Ice jam flooding shall be considered within stream reaches where this phenomenon is <br />known to occur. Ice jam flooding can be analyzed utilizing methodologies available <br />through the U.S. Army Corps of Engineers Cold Regions Research and Engineering <br />Laboratory (CRREL), located in Hanover, New Hampshire. <br />d. Erosion zones and stream migration problems shall be considered on a case-by-case <br />basis, either at the request ofthe sponsoring local government or by Board initiative, <br />within stream reaches where these problems are anticipated or known to occur. <br /> <br />. <br /> <br />K. Published reports and maps. The results ofthe hydrologic analyses, hydraulic analyses, and <br />floodplain delineations shall be summarized in a published report and submitted to the CWCB. <br />- All approximate and detailed floodplain information that is presented to the CWCB for <br />designation and approval shall be properly titled, dated, organized, and bound as a stand-alone <br />document. In addition to the hard copy final report, the CWCB requires that a digital copy of <br />the fmal report be submitted in MS Word and PDF formats. All pertinent technical backup <br />data such as GIS files, hydrologic and hydraulic models, and all pertinent technical backup data <br />shall also be provided to the CWCB in acceptable digital formats. The CWCB shall <br />electronically distribute to interested parties, to the extent possible, pertinent study information. <br />Access to original GIS information will be provided to local governments and other authorized <br />users through a secure and protected web site or other secure means. <br /> <br />a. The published flooded area maps shall show, at a minimum, the flood boundaries, the <br />location of all cross sections used in the hydraulic analysis, the reference line drawn <br />down the center of the floodplain or low flow channel, and a sufficient number of flood <br />contours in order to reconstruct the flood water surface profiles. <br />b. Flood contours (BFEs) shall be show as wavy lines drawn normal to the direction of <br />flow of floodwater and shall extend completely across the area of the 100-year <br />floodplain. Each flood contour shall indicate its elevation to the nearest whole foot. <br />__--'"- The J)ublished flooded area map scale shall be I-inch equals 500 feet or such map scale <br />showing greater detail. FEMA map panels may also be published at 1 inch equals 1,000 <br />feet or 1 inch equals 2000 feet. <br />d. Where discrepancies appear between flooded area maps and water surface profiles, any <br />100-year water surface profile designated and approved by the Board shall take <br />precedence over any corresponding flooded area map for the same stream reach or site <br />location. <br /> <br />. <br /> <br />L. Contractor Qualifications <br />a. Qualified engineers licensed in Colorado shall direct or supervise the floodplain <br />mapping studies and projects within the regulatory floodplain. All floodplain maps, <br />reports and project designs within the regulatory floodplain shall be certified and sealed <br />by the Colorado registered professional engineer of record. <br /> <br />13 <br /> <br />DRAFT <br />