Wastewater Treatment Plants in South Carolina
122 facilities · 265 MGD combined flow
Klarifi tracks 122 publicly owned wastewater treatment plants in South Carolina with a combined average flow of 265 MGD, serving about 1,471,821 residents. 42 plants treat more than 1 MGD and 6 more than 10 MGD; 82 use lagoon systems and 17 have digesters or biogas infrastructure. The largest is Metro Wastewater Treatment Plant in Columbia at 29.87 MGD. 16 NPDES permits expire this year and 10 next year.
Every plant below links to a profile with average and design flow, treatment technology, the NPDES permit and its expiry, a three-year compliance snapshot and the capital projects planned in its city.
122 plant locations in South Carolina; dot size follows average flow.
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 | Technology | Violations (3y) |
|---|---|---|---|---|---|---|---|
| Metro Wastewater Treatment Plant | Columbia | 29.87 | 60 | SC0020940 | May 2023 | Clarifiers, Uncovered lagoons, Biogas silos | 7 |
| Plum Island WWTP | Charleston | 27 | 36 | SC0021229 | Jul 2024 | Clarifiers, Biogas balloons | 3 |
| North Charleston Sewer District WWTP Herbert Site | North Charleston | 15.89 | 32 | SC0024783 | Aug 2024 | Clarifiers | 2 |
| Gsw&sa Schwartz Myrtle Beach & Bucksport Reg Wwtps | Conway | 14.9 | 41.75 | SC0037753 | Jul 2030 | Clarifiers, Carrousels / oxidation ditches | 9 |
| Wcrsa Mauldin Road Wastewater Treatment Plant | Greenville | 12.8 | 29 | SC0041211 | Jun 2008 | Clarifiers, Uncovered lagoons, Biogas silos | 24 |
| City Of Florence Pee Dee River WWTP | Florence | 10.19 | — | SC0045462 | May 2031 | Clarifiers | 5 |
| A. Manning Lynch Wastewater Treatment Facility | Spartanburg | 9.82 | — | SCG570017 | Dec 2030 | Clarifiers, Aerated lagoons, Uncovered lagoons, Biogas silos | 2 |
| Sumter Pocataligo River WWTP | Sumter | 9.15 | — | SC0027707 | Mar 2026 | Clarifiers, Aerated lagoons, Uncovered lagoons, Biogas silos | 49 |
| Lower Berkeley Wastewater Treatment Plant | Goose Creek | 8.6 | 22.5 | SC0046060 | Apr 2024 | Clarifiers, Uncovered lagoons, Carrousels / oxidation ditches | 1 |
| East Rich Co Psd Gills Creek | Columbia | 8.28 | — | SC0038865 | May 2023 | Clarifiers | 2 |
| Pelham WWTP | Greer | 8.2 | 22.5 | SC0033804 | Dec 2023 | Clarifiers, Carrousels / oxidation ditches, Biogas silos | 1 |
| Rifle Range Wastewater Treatment Facility | Mount Pleasant | 7.3 | 14.3 | SC0040771 | Apr 2030 | Clarifiers, Carrousels / oxidation ditches | 0 |
| Bjw&sa Cherry Point WWTP | Ridgeland | 7.12 | 7.5 | SC0047279 | Oct 2029 | Clarifiers, Aerated lagoons, Uncovered lagoons, Carrousels / oxidation ditches | 1 |
| Dorchester Co Lower Dorchester WWTP | Dorchester | 6.7 | 10 | SC0038822 | Nov 2027 | Clarifiers, Uncovered lagoons, Carrousels / oxidation ditches, Biogas silos | 20 |
| City Of Georgetown Sewage Treatment Facility | Georgetown | 4.98 | 12 | SC0040029 | Mar 2024 | Aerated lagoons, Uncovered lagoons, Biogas silos | 0 |
| Summerville WWTF | Summerville | 4.8 | — | SC0037541 | Nov 2024 | Clarifiers, Uncovered lagoons, Carrousels / oxidation ditches | 7 |
| Wcrsa Gilder Creek | Mauldin | 4.8 | 11.3 | SC0040525 | Dec 2023 | Clarifiers, Biogas silos | 1 |
| Gsw&sa/george R Vereen WWTP | Conway | 4.75 | 7 | SC0041696 | Nov 2027 | Clarifiers, Aerated lagoons, Carrousels / oxidation ditches | 31 |
| Bjw&sa Port Royal Water Recl Fac | Port Royal | 4.44 | 7.5 | SC0048348 | Jan 2029 | Clarifiers, Uncovered lagoons, Carrousels / oxidation ditches, Biogas silos | 0 |
| Orangeburg WWTF | Orangeburg | 3.8 | 9 | SC0024481 | Sep 2020 | Clarifiers, Carrousels / oxidation ditches | 0 |
| Generostee Creek Wastewater Treatment Plant | Anderson | 3.25 | 10 | SC0023752 | Mar 2024 | Clarifiers, Aerated lagoons, Biogas silos | 1 |
| Maple Creek Wastewater Treatment Plant | Greer | 2.9 | 5 | SC0046345 | Jul 2024 | Aerated lagoons, Uncovered lagoons | 2 |
| Hilton Head No 1 Psd Wastewater Treatment Plant | Hilton Head Island | 2.88 | 6.4 | SC0046191 | Dec 2025 | Clarifiers, Aerated lagoons, Uncovered lagoons | 17 |
| Gsw&sa/conway WWTP | Conway | 2.87 | 4 | SC0021733 | Mar 2028 | Clarifiers, Uncovered lagoons, Carrousels / oxidation ditches | 29 |
| Bcw&sa Central Berkeley WWTP | Goose Creek | 2.78 | 6 | SC0039764 | Apr 2030 | Clarifiers, Aerated lagoons, Carrousels / oxidation ditches | 4 |
South Carolina plants by treatment technology
All 122 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 September 11, 2026.