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

Appendix A, § 4.3 sets the building elevation standards for the Floodfringe District (FF). They bind only land mapped in the floodfringe, and § 4.2 allows any structure, land use or development there only if the § 4.3 standards are met, no other ordinance prohibits the use, and the permits or certificates required under § 7.1 have been issued.

The benchmark is the flood protection elevation. Section 10.0 defines it as an elevation of two feet of freeboard above the water surface profile elevation designated for the regional flood. Freeboard is a safety factor expressed in feet above a calculated flood level, meant to cover ice jams, debris accumulation, wave action, obstructed bridge openings and floodways, watershed urbanization and loss of flood storage.

For residential uses, § 4.3(1) covers any habitable structure, including a manufactured home, that is erected, constructed, reconstructed, altered or moved into the floodfringe. The lowest floor, excluding the basement or crawlway, must be at or above the flood protection elevation on fill. The fill must be one foot or more above the regional flood elevation and extend at least 15 feet beyond the limits of the structure. The Department may authorize other floodproofing measures if the elevations of existing streets or sewer lines make the fill standard impractical.

A basement or crawlway floor may be placed at the regional flood elevation only if it is floodproofed to the flood protection elevation, and no basement or crawlway floor is allowed below the regional flood elevation. Contiguous dryland access to land outside the floodplain is required, with a narrow exception where existing street or sewer elevations make it impractical and the municipality holds written assurance of rescue by wheeled vehicles or an approved natural disaster plan.

A detached accessory structure under 600 square feet and valued under $10,000.00 can have its lowest floor as much as two feet below the regional flood elevation, but only where flood velocities are no more than two feet per second. Manufactured homes in existing parks must have the lowest floor elevated to the flood protection elevation, and buoyant, flammable or injurious materials must be stored at or above it.