Beaufort County, SC Stormwater Regulations

Beaufort County operates under a Small MS4 NPDES permit and enforces stormwater regulations through its Stormwater Management Utility. The county's OCRM coastal overlay adds permitting requirements beyond standard state rules. State penalties reach $10,000 per day, while county fines can hit $25,000 per month for non-compliance.

Primary source: South Carolina Department of Environmental Services (SCDES)

Permit Requirements

Beaufort County enforces stormwater permitting at both state and local levels. At the state level, SCDES requires an NPDES Construction General Permit (SCR100000) for any project disturbing one acre or more. The county's local ordinance lowers this threshold to 10,000 square feet for land disturbance permits.

Projects within the OCRM coastal critical area must also obtain a Critical Area Permit from the SC Department of Health and Environmental Control's Office of Ocean and Coastal Resource Management. This applies to most tidal and coastal areas within Beaufort County, including properties near the Beaufort River, Port Royal Sound, and Calibogue Sound.

The county requires a Stormwater Pollution Prevention Plan (SWPPP) for permitted construction projects. The SWPPP must detail erosion and sediment control measures, post-construction stormwater management BMPs, and a maintenance schedule for all permanent facilities.

Inspection Obligations

The Beaufort County Stormwater Management Utility conducts inspections of both construction sites and permanent stormwater facilities. Construction sites must be inspected by a qualified inspector at least once per week and within 24 hours of any rain event producing 0.5 inches or more.

For permanent BMPs, property owners must conduct annual inspections and maintain documentation. The county may conduct its own inspections at any time and can require corrective action within a specified timeframe. Inspection reports must document the condition of all inlet and outlet structures, embankments, vegetation, sediment accumulation, and structural components.

HOA-maintained stormwater ponds and detention basins are subject to the same inspection requirements. The county's Stormwater Management Utility maintains a database of permitted facilities and tracks compliance status.

Penalty Structure

Beaufort County's stormwater enforcement operates on two levels. At the state level, SCDES can assess civil penalties up to $10,000 per day per violation under the South Carolina Pollution Control Act (SC Code Section 48-1-330). The state can also issue stop-work orders, revoke permits, and require remediation.

At the county level, the Stormwater Management Utility can impose penalties up to $25,000 per month for violations of local stormwater ordinances. The county's enforcement process typically begins with a notice of violation, followed by a compliance deadline. If the property owner fails to correct the violation, the county can impose daily fines, perform the work and bill the costs to the owner, or place a lien on the property.

OCRM violations carry additional penalties under the SC Coastal Zone Management Act. Unauthorized work in the coastal critical area can result in mandatory restoration, permit revocation, and fines assessed per violation.

Key BMPs

Beaufort County's coastal environment and high water table influence BMP selection. Common approved BMPs include:

• Wet detention ponds - The most common BMP in Beaufort County. Must maintain a permanent pool and be sized to treat the first 1 inch of runoff from the contributing drainage area.
• Bioretention systems - Engineered planting beds that filter stormwater. Effective in coastal areas where space is limited.
• Constructed wetlands - Natural treatment systems that work well with Beaufort's hydrology. Require larger footprints but provide excellent pollutant removal.
• Permeable pavement - Allowed in low-traffic areas. Must include an underdrain system due to Beaufort's high water table conditions.
• Vegetated swales - Used for conveyance and treatment along roadways and in residential developments. Must be designed to handle tidal backflow in coastal areas.

Local Ordinances

Beaufort County's stormwater ordinance (Chapter 106, Article V of the County Code) establishes local standards that exceed state minimums in several areas. The ordinance requires stormwater management for developments disturbing as little as 10,000 square feet, compared to the state's one-acre threshold.

The county operates a Stormwater Utility that funds stormwater infrastructure maintenance, flood mitigation, and water quality programs through a stormwater utility fee assessed on all developed properties. The fee is based on impervious surface area.

Beaufort County also participates in the Community Rating System (CRS) under the National Flood Insurance Program, which provides flood insurance premium discounts to property owners. Maintaining stormwater compliance is a component of the county's CRS rating.