Owensboro, KY Environmental Rules: Flood Elevation Requirements (2026)

Zoning Ordinance Section 18-5(b) sets specific flood-hazard-reduction standards for areas where base flood elevation data has been established. Subsection (1), covering residential construction, requires that new construction or substantial improvement of any residential structure, including a manufactured home, have its lowest floor, including any basement, and its mechanical equipment elevated no lower than one foot above the base flood elevation. Ductwork must be installed above the ceiling unless the finish floor is at least two feet above both the base flood elevation and the finish grade.

Where solid foundation perimeter walls elevate the structure, flood openings must be provided under the standards of Section 18-5(b)(3) to let flood waters move through unimpeded. In an AO Zone lacking a specified depth number, the structure must be elevated at least two feet above the highest adjacent grade, and in an A Zone lacking FEMA technical data, the Floodplain Administrator determines the base flood elevation using hydrologic and hydraulic analysis, historical data, or reasonable judgment; the same one-foot freeboard applies in all other zones.

Once construction is complete, the lowest floor elevation must be certified by a licensed professional engineer or surveyor and verified by the community building inspection department, with that certification filed with the Floodplain Administrator. Nonresidential structures face a parallel one-foot freeboard under Section 18-5(b)(2), with a flood-proofing alternative available if the lowest floor is built lower.