55 ILCS 5/5-40001: Floodplain regulations.

Counties are authorized to adopt and enforce floodplain regulations consistent with Federal Emergency Management Agency regulations that implement the National Flood Insurance Act of 1968, as amended. For the purposes of preventing flood damages and preserving the flood carrying capacity of streams, floodplain regulations shall apply to all buildings, structures, construction, excavation, and filling in the floodplain whether or not the land, buildings, structures, construction, excavation, or filling are for agricultural purposes. The Department of Natural Resources shall prepare manuals and model ordinances and shall advise counties on achieving floodplain regulation purposes without unnecessarily interfering with land uses.