Activated sludge and clarifiers: wastewater treatment plants in South Carolina
59 plants · 49% of the state · 232 MGD reported by 57 plants
Klarifi identifies 59 publicly owned wastewater treatment plants with activated sludge and clarifiers in South Carolina, 49% of the 120 plants in the state (232 MGD reported by 57 plants). The largest is Metro Wastewater Treatment Plant in Columbia at 27.08 MGD.
Activated sludge is the standard mechanical process for cities: aeration basins where bacteria consume organic matter, followed by clarifiers that settle the biomass out. These plants are identified by their circular or rectangular clarifiers and by the suspended-growth process code, and they are the main market for blowers, diffusers, clarifier mechanisms and instrumentation.
The largest activated sludge plants in South Carolina
| # | Facility | City | Avg flow (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|---|
| 1 | Metro Wastewater Treatment Plant | Columbia | 27.08 | SC0020940 | May 2023 | 7 |
| 2 | Plum Island WWTP | Charleston | 21.36 | SC0021229 | Jul 2024 | 3 |
| 3 | Gsw&sa Schwartz Myrtle Beach & Bucksport Reg Wwtps | Conway | 14.52 | SC0037753 | Jul 2030 | 7 |
| 4 | North Charleston Sewer District WWTP Herbert Site | North Charleston | 14.5 | SC0024783 | Aug 2024 | 2 |
| 5 | Wcrsa Mauldin Road Wastewater Treatment Plant | Greenville | 13.25 | SC0041211 | Jun 2008 | 22 |
| 6 | City Of Florence Pee Dee River WWTP | Florence | 12.36 | SC0045462 | May 2031 | 5 |
| 7 | A. Manning Lynch Wastewater Treatment Facility | Spartanburg | 10.35 | SCG570017 | Dec 2030 | 2 |
| 8 | Sumter Pocataligo River WWTP | Sumter | 9.19 | SC0027707 | Mar 2026 | 49 |
| 9 | Lower Berkeley Wastewater Treatment Plant | Goose Creek | 8.77 | SC0046060 | Apr 2024 | 1 |
| 10 | Pelham WWTP | Greer | 8.57 | SC0033804 | Dec 2023 | 1 |
Contacts and project signals for every plant on this list
Klarifi adds verified decision-maker contacts, permit limits, discharge monitoring data and the capital projects planned in each city, filterable by technology, size and compliance record.
Other technologies in South Carolina
Activated sludge and clarifiers in other states
Activated sludge and clarifiers 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: Activated sludge · Biological nutrient removal · Equalization tank · POTW · MGD · all terms