St. Tammany Parish, LA Environmental Rules: Flood Elevation Requirements (2026)

The parish's Flood Damage Prevention Ordinance, Sec. 900-6.7 of the Unified Development Code, applies to all areas of special flood hazard within St. Tammany Parish's jurisdiction, based on the Flood Insurance Study and FIRM dated April 21, 1999. Any owner must obtain a Floodplain Development Permit from the Floodplain Administrator, a role assigned to the Chief Building Official, before locating, altering or changing the use of a structure or land in a mapped flood zone.

Section (E)(2)(a) sets the elevation standard for residential construction: new construction and substantial improvements must have the lowest floor, including any basement, at or above the base flood elevation plus 12 inches, certified by a registered professional engineer, architect, or land surveyor. Nonresidential buildings face the same 12-inch freeboard, or must be floodproofed watertight to that height with certification from an engineer or architect. Enclosures below the lowest floor used only for parking, access, or storage must have flood vents: at least two openings on separate walls totaling one square inch of net area per square foot of enclosed space, with the bottom of each opening no higher than one foot above grade. Manufactured homes in Zones A1-30, AH and AE must have the bottom of the I-beam at or above BFE plus 12 inches on a permanent, anchored foundation. Coastal High Hazard Areas (V zones) require elevation on pilings or columns to the same plus-12-inch standard, with breakaway walls below.

The Board of Adjustments hears variance requests and appeals from Floodplain Administrator decisions; further appeal runs to the 22nd Judicial District Court.