Beloit, WI Environmental Rules: Flood Elevation Requirements (2026)

Chapter 19's Floodplain Zoning Ordinance (Article V) divides Beloit's regional floodplain into a floodway district, a floodfringe district and a general floodplain district, all mapped on the FIRM under §5-405. Under §5-419, a structure proposed in an AO or AH zone must have its lowest floor built to whichever is higher: the flood protection elevation, 2 feet above the highest adjacent grade, or the depth shown on the FIRM. The city's definitions section, §5-433, fixes the flood protection elevation itself at 2 feet of freeboard above the water surface profile elevation set for the regional flood, a margin meant to absorb ice jams, debris and wave action that push flood heights above the calculated level.

Residential structures elsewhere in the floodfringe must have their lowest floor, including basement, elevated to or above the flood protection elevation using fill, pilings, columns, posts or perimeter walls, or dry floodproofed under §5-428 in commercial cases. The Zoning Officer administers all floodplain development permits and can deny a permit outright under §5-406 if a project would obstruct flow or raise the regional flood height. No watercourse may be altered or relocated in a mapped floodplain without notifying adjoining municipalities, the DNR and FEMA and securing all state and federal permits first, per §5-407. 30, Wis. Stats.