S.C. Floodplain Management — NFIP Participation / Title 49 Chapter 23 (SC)
Tracked preemption from the South Carolina overlay bundle.
Overview
← All state preemptionsSouth Carolina overlay roll-upSouth Carolina zoning wikiSouth Carolina building codesFederal overlaysGlossaryFederal-conflict: Yes
Effective
1981-06-09
Sunset
—
Authority
state
Scope
state:SC
Other South Carolina preemptions
S.C. Short-Term Rentals — No State Preemption (explicit non-preemption)S.C. ADU / Density / Design Review — No State Preemption (explicit non-preemption)S.C. Military Installation Compatibility — AICUZ / JLUS CoordinationS.C. §6-29-1145 — Manufactured Housing Zoning Parity RuleS.C. Brownfields / Voluntary Cleanup Program — §44-56-710 et seq.S.C. Local Government Comprehensive Planning Enabling Act of 1994 — Procedural FloorS.C. Scenic Rivers Act of 1989 — Designated Scenic, Recreational, and Natural RiversS.C. Beachfront Management Act — OCRM Baseline / Setback Line Overlay
Trigger predicate
When this evaluates true for a parcel, the law's preempted fields take precedence over base zoning.
parcel.in_nfip_sfha == TruePreempted fields
4 fields on the base district schema are rewritten when the trigger fires.
| Field | Op | Value | Note |
|---|---|---|---|
base_districts[*].floodplain_development_review | require | floodplain_development_permit | All development in FEMA Special Flood Hazard Areas (SFHA) requires a Floodplain Development Permit per local Flood Damage Prevention Ordinance meeting NFIP minimums (44 CFR §60.3) and SC NFIP coordination. |
base_districts[*].lowest_floor_elevation_ft_above_bfe | floor_at | 1 | SC NFIP state model ordinance requires lowest floor at or above Base Flood Elevation; minimum 1-ft freeboard recommended; many CRS communities require 2-3 ft. |
base_districts[*].floodway_no_rise_certification | require | True | 44 CFR §60.3(d)(3): no encroachment in regulatory floodway that would increase base flood levels — no-rise certification required. |
base_districts[*].substantial_improvement_threshold_pct | cap_at | 50 | Substantial improvement / damage ≥50% market value triggers full NFIP compliance for the entire structure. |
Citation
Authority source
S.C. Code Ann. §§49-23-10 through 49-23-130 (Flood Plain Management); §48-39 (coastal floodplain coordination); 44 CFR §60.3 (FEMA NFIP minimums); S.C. NFIP State Coordinator (SCDNR Flood Mitigation Program)
§ §§49-23-10 — 49-23-130
Research notes
SC is a state-NFIP coordinating state via the SCDNR Flood Mitigation Program. Title 49 Chapter 23 provides state-level flood-management authority and authorizes coordination with federal NFIP. Hurricane-coastal exposure (post-Hugo 1989, Floyd 1999, Matthew 2016, Florence 2018, Ian 2022) drives strong CRS participation — Charleston, Mt. Pleasant, North Charleston, Beaufort, Hilton Head Island, and Myrtle Beach are CRS communities with stricter local freeboard. Federal-conflict-check enabled because Title 48 Chapter 39 Beachfront Management Act and Title 49 Chapter 23 floodplain rules stack with federal NFIP — the stricter standard prevails.