Lagoon systems: wastewater treatment plants in South Carolina
75 plants · 63% of the state · 133 MGD reported by 70 plants
Klarifi identifies 75 publicly owned wastewater treatment plants with lagoon systems in South Carolina, 63% of the 120 plants in the state (133 MGD reported by 70 plants). The largest is Metro Wastewater Treatment Plant in Columbia at 27.08 MGD.
Lagoon systems treat wastewater in large earthen ponds over weeks of retention time, with or without mechanical aeration. They serve thousands of small towns because they are cheap to run, but they struggle with ammonia and nutrient limits, fill with sludge over decades and are the plants most often converted or upgraded when a permit is renewed.
The largest lagoons 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 | Wcrsa Mauldin Road Wastewater Treatment Plant | Greenville | 13.25 | SC0041211 | Jun 2008 | 22 |
| 3 | A. Manning Lynch Wastewater Treatment Facility | Spartanburg | 10.35 | SCG570017 | Dec 2030 | 2 |
| 4 | Sumter Pocataligo River WWTP | Sumter | 9.19 | SC0027707 | Mar 2026 | 49 |
| 5 | Bjw&sa Cherry Point WWTP | Ridgeland | 6.85 | SC0047279 | Oct 2029 | 1 |
| 6 | Dorchester Co Lower Dorchester WWTP | Dorchester | 6.84 | SC0038822 | Nov 2027 | 16 |
| 7 | Summerville WWTF | Summerville | 4.75 | SC0037541 | Nov 2024 | 7 |
| 8 | Gsw&sa/george R Vereen WWTP | Conway | 4.61 | SC0041696 | Nov 2027 | 31 |
| 9 | Bjw&sa Port Royal Water Recl Fac | Port Royal | 3.58 | SC0048348 | Jan 2029 | 0 |
| 10 | City Of Georgetown Sewage Treatment Facility | Georgetown | 3.57 | SC0040029 | Mar 2024 | 0 |
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
Lagoon systems in other states
Lagoon systems 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 · Biosolids · Oxidation ditch · Anaerobic digester · all terms