Gulfport, MS Environmental Rules: Flood Elevation Requirements (2026)

Appendix B, Article 5, Sec. B(1)-(2) sets the elevation floor for construction in areas with base flood elevation data. New construction and substantial improvement of any residential building, including manufactured homes, must have the lowest floor, including any basement, elevated a minimum of 1 foot above the base flood elevation (BFE); non-residential buildings face the identical 1-foot floor, though they may instead be dry flood-proofed watertight up to that same elevation plus 1 foot of freeboard, certified by a registered professional engineer or architect, and only where flood velocities run 5 feet per second or less.

Article 2 defines freeboard as the safety margin above BFE that compensates for unknowns like wave action and watershed urbanization that push flood heights above the modeled level, which is why Gulfport treats the 1-foot figure as a floor rather than decoration. Article 5, Sec. A applies to every special flood hazard area regardless of zone: mechanical, electrical, and plumbing equipment must sit at least 1 foot above BFE, new construction must use flood-damage-resistant materials, and enclosed areas below the lowest floor must have flood vents equalizing hydrostatic pressure.

Critical facilities face a much higher bar under Article 5, Sec. 2%-annual-chance flood elevation if that is higher. The ordinance exists to keep the City of Gulfport eligible for the National Flood Insurance Program, and the Ordinance No. 2929 preamble notes it was updated in 2017 at the request of the Mississippi Emergency Management Agency to reflect new FEMA flood hazard data.