2004.05.03 ORD 2004-386, 387, 388

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elevation of two feet above the 100©year flood profile. (4) Any structures, facilities, or embankments within the flood plain will be capable of passing the 100©year flood without increasing the elevation of the 100©year flood profile or creating excessive velocities as determined by the District Engineer. Permitting Requirements for Flood Plain Management Sector B Sector B contains those subwatersheds where the percentage of flood plain to total area is greater than twelve percent, and the topography is characterized by a general slope condition of predominantly less than twelve percent. Flood Plain Management Sector B includes subwatersheds 1,2,3,6,9,10,11,12a and 12b. (a) Construction of impervious areas will not be allowed within the designated groundwater recharge areas of the Prairie du Chien Jordan formation except for road construction, trails, and other recreational improvements. (b) To protect water quality and the conveyance capacity of the flood plain, the District will not permit site development which would involve the outside storage of soluble, toxic, or buoyant materials. Examples of acceptable flood plain uses include open space, golf courses, and parking surfaces located outside of designated recharge areas with less than six inches of flooding occurring over the surface. (c) Encroachment may occur in the flood plain areas of Flood Plain Management Sector B if all the following conditions exist: (1) The encroachment lies within the floodway fringe area of the 100©year flood plain in those areas where floodway has been identified, or in the absence of an established floodway, compensatory (live) storage is excavated. (2) The encroachment does not result in increasing the 100©year flood profile within the floodway portion of the flood plain by more than 0.5©foot or create velocities exceeding 2.5 feet/second or as determined by the District Engineer. (3) The encroachment does not violate the principle of "equal encroachment." (4) The encroachment does not result in violation of the District's Wetland Alteration Rule F. (5) Structures and facilities subject to flood damage built within the 100 -year flood will have two feet of freeboard between the lowest floor and the 100 -year flood profile. 4. DRAINAGE EASEMENTS. Applicant will provide drainage and flowage/ponding easements over flood plain areas inundated during the 100 year flood and drainage easements within 100 feet from the centerline of Rice Creek, Hardwood Creek, Clearwater Creek, and Ramsey County Ditch #2, within fifty feet of the centerline of county and judicial ditches, or within twenty five feet of the centerline of any major drainageway of the District.