(A) No development in the floodplain shall include locating or storing chemicals, explosives, buoyant materials, flammable liquids, pollutants or other hazardous or toxic materials below the flood protection elevation unless such materials are stored in a floodproofed and anchored storage tank and certified by a professional engineer or floodproofed building constructed according to the requirements of § 152.07.
(B) Public utilities and facilities such as sewer, gas and electric shall be located and constructed to minimize or eliminate flood damage.
(C) Public sanitary sewer systems and water supply systems shall be located and constructed to minimize or eliminate infiltration of flood waters into the systems and discharges from the systems into flood waters. Manholes or other above-ground openings located below the flood protection elevation shall be watertight.
(D) (1) New and replacement on-site sanitary sewer lines or waste disposal systems shall be located and constructed to avoid impairment to them or contamination from them during flooding.
(2) The system can be designed and certified by a licensed professional engineer and must be approved by the State Department of Public Health as per 77 ILCS 905. Leach fields are not allowed in the SFHA.
(E) Construction of new or substantially improved critical facilities shall be located outside the limits of the floodplain. Construction of new critical facilities shall be permissible within the floodplain if no feasible alternative site is available. Critical facilities constructed within the SFHA shall have the lowest floor (including basement) elevated or structurally dry-floodproofed to the 0.02% annual flood frequency elevation or three feet above the base flood elevation, whichever is greater. Floodproofing and sealing measures must be taken to ensure that toxic substances will not be displaced by or released into floodwaters. Access routes elevated to or above the level of the base flood elevation shall be provided to all critical facilities.
(F) All other activities defined as development shall be, and as development shall be designed, so as not to alter flood flows or increase potential flood damages.
(G) Dams are classified as to their size and their hazard/damage potential in the event of failure. Permits for dams may be required from IDNR/OWR. Contact IDNR/OWR to determine if a permit is required. If a permit is required, a permit application must be made to IDNR/OWR prior to the construction or major modification of jurisdictional dams.
(H) The Floodplain Manager shall require a conditional letter of map revision (CLOMR)/letter of map revision (LOMR) prior to the issuance of a development permit for:
(1) Proposed development which will increase the BFE by more than 0.1 feet in riverine area where FEMA has provided a BFE but no floodway;
(2) Once a CLOMR has been issued, the development permit may be issued for site grading and structures necessary in the area of the map change to achieve the final LOMR. Upon completion, the applicant shall submit as-built certifications, as required by FEMA, to achieve a final LOMR prior to the release of final development permits. Review this section for the construction of buildings in a floodplain issued a LOMR based on fill; and
(3) When construction of a building following a LOMR based on fill is requested, the condition where a site in the floodplain is removed due to the use of fill to elevate the site above the BFE, the applicant may not apply for a permit from the county to construct the lowest floor of a building below the BFE in the floodplain.
(Ord. 21-4, passed 11-9-2021)