Darlington County, SC Environmental Rules: Flood Elevation Requirements (2026)

The Development Standards Ordinance, Appendix A of the county code, governs floodplain construction because the county has no separate zoning ordinance. Section 3.4.4(A) directs Development Services to confirm a building site is reasonably safe from flooding before a permit issues, and requires applicants to show new structures cannot be relocated out of the special flood hazard area. Where FEMA has published base flood elevation data, Section 3.4.4(B)(1) sets the specific residential standard: the lowest floor of any new or substantially improved residential structure, including manufactured homes, must sit no lower than two feet above the base flood elevation, and basements are prohibited outright.

Builders who elevate on solid perimeter foundation walls must install flood openings sized to automatically equalize hydrostatic pressure, per the venting standards in Section 3.4.4(B)(5). Non-residential structures face the same two-foot freeboard under Section 3.4.4(B)(2), with a floodproofing alternative available if certified by a registered engineer or architect. The planning director, designated as local floodplain administrator under Section 3.4.3(A), reviews permit applications, requires elevation certification after the lowest floor is poured (Section 3.4.3(C)(7)), and can issue stop-work orders for noncompliant construction. Variances run through the Darlington County Planning Commission sitting as the appeal board under Section 3.4.5(A).