Effingham County, GA Environmental Rules: Flood Elevation Requirements (2026)

Sec. 34-82(1) of the county's flood damage prevention chapter (Ord. of 3-3-15, amended Ord. of 4-18-2023) requires that where base flood elevation data are available, new construction and substantial improvement of any structure or manufactured home have the lowest floor, including basement, elevated no lower than one foot above the base flood elevation, the one-foot cushion Sec. 34-5 defines as freeboard against unknown factors like wave action and urbanization effects. If solid foundation perimeter walls are used, the structure needs equalizing openings under Sec. 34-81(4).

All heating, air conditioning, electrical, ventilation, and plumbing equipment must also sit at or above that one-foot freeboard line. Sec. 34-82(2) lets non-residential structures floodproof instead of elevate, but the design must be watertight to one foot above base flood elevation and certified by a registered professional engineer or architect. Sec. 34-82(3) applies the same one-foot freeboard to manufactured homes and, for units in existing manufactured home parks, adds a 36-inch minimum pier height above grade. Where FEMA has not mapped base flood elevation data, Sec.

34-83(3) instead requires the lowest floor elevated at least three feet above the highest adjacent grade, and Sec. 34-84 applies the Sec. 34-82 elevation standard to zones with established base flood elevations but no floodway. A registered land surveyor or professional engineer must certify the as-built lowest-floor elevation to the county engineer under Sec. 34-47(2), referenced to NAVD 88, before the project can proceed past that stage; work done before certification is submitted proceeds at the permit holder's own risk.