Eagan, MN Environmental Rules: Flood Elevation Requirements (2026)

City Code § 11.66, Subd. 2 defines "regulatory flood protection elevation" as a point not less than one foot above the water surface profile associated with the regional (100-year) flood, plus any increase in flood heights caused by floodway encroachments; it is the elevation to which regulated uses must be elevated or floodproofed. Building on that base, Subd. 5.G.1 requires every structure in the Flood Fringe District, including accessory structures, to have the lowest floor of its lowest enclosed area, basement or crawl space included, no less than two feet above that regulatory flood protection elevation.

When fill is used to reach that height, the finished fill must extend at the same elevation at least 15 feet beyond the structure's outside walls, so the pad cannot simply taper down at the foundation line. Subd. 5.I lets a builder use stilts, pilings, or an above-grade enclosed area such as a crawl space or tuck-under garage instead of fill, but the design must be certified by a registered professional engineer or architect as meeting the state building code, and enclosed areas below the freeboard line need automatic flood-venting openings sized to one square inch per square foot of enclosed area.

Residential basements are banned outright if any part sits less than two feet above the regulatory flood protection elevation under Subd. 5.I.2. Before the city signs off, § 11.66, Subd. 12.C requires certification by a registered engineer, architect, or land surveyor that the finished fill and building elevations were actually built as approved, and the community development director keeps that elevation record on file.