Darlington County, SC Environmental Rules: Stormwater Management (2026)

Darlington County created its Municipal Separate Storm Sewer System (MS4) Area Stormwater Management Protection Overlay District under Appendix A, Article Seventeen, mapped in Plat Book 204 at page 45 and administered by the county's Planning Department. Section 17.4.3 prohibits illicit discharges and illicit connections to the storm drain system, including any past connection that conveys sewage into the MS4, and Section 17.4.4 gives the county the right to enter and inspect any facility subject to an NPDES stormwater permit as often as necessary, with a search warrant available if access is refused.

Section 17.5.1 requires an approved stormwater pollution prevention plan (SWPPP) and a certificate of approval from the director of planning before any land disturbance of one acre or more, plus coverage under SCDHEC's General Permit SCR100000; single-family homes disturbing less than an acre and outside a subdivision are exempt. The application fee is $125 forwarded to DHEC with the notice of intent plus a $100-per-acre county review fee, capped at $2,000, for a maximum of $2,125 under Section 17.5.4. Inspections during construction must occur at least every seven days, or every 14 days plus within 24 hours of a 0.5-inch storm, per Section 17.5.6.

Under Section 17.4.9, a violator gets written notice, a hearing before the director of planning within ten days, and an order to correct within 60 days (less if there is imminent danger); an unappealed or unheeded order triggers a $500 fine, with each day of continued noncompliance a separate offense, and failure to correct within five days becomes a misdemeanor. The county may also suspend MS4 access without notice for an imminent threat.