South Carolina Stormwater Regulations

State Regulatory Overview

The South Carolina Department of Environmental Services (SCDES) serves as the primary authority for stormwater regulation statewide. SCDES took over these responsibilities from SCDHEC following the agency restructuring. The department administers all NPDES stormwater permits, reviews Stormwater Pollution Prevention Plans (SWPPPs), and conducts enforcement actions for non-compliance.

In coastal areas, the Office of Ocean and Coastal Resource Management (OCRM) adds a second layer of permitting. OCRM regulates development within critical areas along SC's coastline and imposes additional stormwater treatment, setback, and density requirements. Any project within the 8 coastal counties that falls within OCRM's jurisdiction needs both SCDES stormwater permits and OCRM critical area permits.

South Carolina's stormwater framework is built on the federal Clean Water Act's NPDES program, supplemented by state-specific laws including the SC Pollution Control Act, the Stormwater Management and Sediment Reduction Act, and the Coastal Zone Management Act.

County Coverage

AUE Land provides stormwater services across all 8 of South Carolina's coastal counties. Each county has its own local stormwater ordinances that implement state permit requirements.

Key State Laws

• SC Pollution Control Act (S.C. Code 48-1) - The primary environmental enforcement law. Authorizes SCDES to issue permits, conduct inspections, and assess penalties up to $10,000 per day for violations including unpermitted discharges and failure to maintain stormwater controls.
• Stormwater Management and Sediment Reduction Act (S.C. Code 48-14) - Requires land-disturbing activities of one acre or more to obtain a stormwater permit and implement erosion and sediment controls. Mandates post-construction BMP maintenance agreements.
• SC Coastal Zone Management Act (S.C. Code 48-39) - Establishes OCRM's authority over development in the coastal zone. Requires critical area permits for projects within specified distances of tidal waters, beaches, and primary sand dunes.
• SC Water Quality Standards (R.61-68) - Defines water quality classifications and standards that stormwater discharges must meet. Includes anti-degradation provisions for Outstanding National Resource Waters and high-quality waters.

Permit Types

Construction General Permit (CGP) - SCR100000

The SC CGP covers all land-disturbing activities of one acre or more. Operators must file a Notice of Intent (NOI), develop a SWPPP, implement erosion and sediment controls, and maintain post-construction BMPs. The previous permit expired February 28, 2026, and SCDES is processing the renewal. During the interim, existing permittees operate under the expired permit's terms until the new one is issued.

MS4 Permits

SC's MS4 permits require municipalities to implement stormwater management programs covering six minimum control measures: public education, public involvement, illicit discharge detection, construction site runoff control, post-construction management, and pollution prevention. Phase I permits cover larger municipalities (Charleston metro area), while Phase II permits cover smaller urbanized areas. Most coastal communities hold Phase II permits.

Industrial Stormwater Permits

Industrial facilities with outdoor operations exposed to rainfall must obtain coverage under SC's Multi-Sector General Permit or an individual stormwater permit. These permits require stormwater sampling, pollution prevention plans, and regular monitoring reports to SCDES.

Frequently Asked Questions