Construction in a Flood Fringe Area

Section 506 Section 506.208  Construction in a Flood Fringe Area A new earthen livestock waste lagoon may be constructed within the portion of a 100-year floodplain that is within the flood fringe and outside the floodway if the facility is designed and constructed so that livestock waste is not readily removed during flooding and meets the requirements set forth in the Rivers, Lakes, and Streams Act [615 ILCS 5] , Section 5-40001 of the Counties Code [55 ILCS 5/5-40001] , and executive order number 4 (1979). [510 ILCS 77/15(a-5)(1)] The following criteria must be incorporated into the design of a lagoon proposed for construction in the flood fringe of a 100-year floodplain: a)         The lagoon berms must be designed and constructed to withstand the hydrostatic pressures from flood waters that may be exerted on the berms during a flood event. b)         The elevation of the lowest point on the berm top must be at the summation of the elevation of the 100-year flood plus a freeboard.  The freeboard height must be a minimum of two feet. c)         For lagoons with unequal length and width dimensions, the lagoon must be oriented with the longest dimension parallel to the expected direction of floodwater flow. d)         Any monitoring wells installed under Section 506.206 must be mounted flush with the surrounding soil surface or otherwise physically protected from flood waters. e)         The owner or operator of the livestock waste handling facility may, upon written request and with written approval from the Department, modify or exceed these standards to meet site specific objectives.  The owner or operator must demonstrate that such modification will be at least as protective of the groundwater, the surface water, and the structural integrity of the livestock waste handling facility as the requirements of this Part.