Wastewater treatment plants in South Carolina
120 facilities · 260 MGD combined flow
Klarifi tracks 120 publicly owned wastewater treatment plants in South Carolina with a combined average flow of 260 MGD, serving about 1,471,821 residents. 46 plants treat more than 1 MGD and 7 more than 10 MGD; 75 use lagoon systems and 17 have digesters or biogas infrastructure. The largest is Metro Wastewater Treatment Plant in Columbia at 27.08 MGD. 16 NPDES permits expire this year and 10 next year.
Every plant below links to a profile with average and design flow, the NPDES permit and its expiry, a three-year compliance snapshot and the capital projects planned in its city. Treatment technology and verified contacts are shown with a free Klarifi account.
120 plant locations in South Carolina; dot size follows average flow. Boundaries: U.S. Census Bureau.
NPDES permits and renewals in South Carolina
Every plant discharges under an NPDES permit that is renewed every five years, usually with tighter limits. The renewal year is the year a plant budgets for upgrades.
Largest wastewater treatment plants in South Carolina
| Facility | City | Avg flow (MGD) | Design (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|---|
| Metro Wastewater Treatment Plant | Columbia | 27.08 | 60 | SC0020940 | May 2023 | 7 |
| Plum Island WWTP | Charleston | 21.36 | 36 | SC0021229 | Jul 2024 | 3 |
| Gsw&sa Schwartz Myrtle Beach & Bucksport Reg Wwtps | Conway | 14.52 | 41.75 | SC0037753 | Jul 2030 | 7 |
| North Charleston Sewer District WWTP Herbert Site | North Charleston | 14.5 | 32 | SC0024783 | Aug 2024 | 2 |
| Wcrsa Mauldin Road Wastewater Treatment Plant | Greenville | 13.25 | 29 | SC0041211 | Jun 2008 | 22 |
| City Of Florence Pee Dee River WWTP | Florence | 12.36 | — | SC0045462 | May 2031 | 5 |
| A. Manning Lynch Wastewater Treatment Facility | Spartanburg | 10.35 | — | SCG570017 | Dec 2030 | 2 |
| Sumter Pocataligo River WWTP | Sumter | 9.19 | — | SC0027707 | Mar 2026 | 49 |
| Lower Berkeley Wastewater Treatment Plant | Goose Creek | 8.77 | 22.5 | SC0046060 | Apr 2024 | 1 |
| Pelham WWTP | Greer | 8.57 | 22.5 | SC0033804 | Dec 2023 | 1 |
Treatment technology for each plant is shown with a free Klarifi account. Create one →
South Carolina plants by treatment technology
All 120 plants in South Carolina
Wastewater treatment in South Carolina: questions
Sources and methodology
Flow, permit and violation figures come from the EPA's ICIS-NPDES discharge monitoring records. Population served comes from the Clean Watersheds Needs Survey 2022. Treatment structures are identified by Klarifi's review of aerial imagery, and capital improvement projects are extracted from published municipal budget documents. Violations are counted over the last three years of monitoring reports.
Data refreshed October 26, 2026.
Wastewater terms: WWTP · POTW · MGD · NPDES permit · Filter press · FOG · all terms
Cite this page
Journalists, researchers and educators are welcome to quote these figures. Please credit Klarifi as the source and link to this page.
Klarifi. “Wastewater treatment plants in South Carolina.” Updated October 26, 2026. https://klarifi.io/facilities/south-carolinaNeed a custom cut of the data for a state, a county or a list of plants? Email info@klarifi.io.