How many wastewater permits expire in South Carolina in 2028?

5 NPDES permits held by publicly owned wastewater treatment plants in South Carolina expire in 2028, covering a combined average flow of 6 MGD. The busiest month is Mar 2028 with 2 expiries.

What happens when an NPDES permit expires?

The plant must have applied for renewal at least 180 days before the expiry date. If the agency has not reissued the permit by then, the old permit is administratively continued and stays enforceable. The reissued permit typically carries updated effluent limits based on the latest water-quality standards, which is what drives upgrade projects.

Which is the largest plant with a permit expiring in South Carolina in 2028?

Gsw&sa/conway WWTP in Conway, treating about 3.11 MGD under permit SC0021733, expiring Mar 2028.

How do I get contacts for the plants on this list?

Every plant links to its profile with flow, permit and compliance data. Treatment technology and verified decision-maker contacts for each plant, and the same list for every state and year, are available in Klarifi with a free account.

Try for free Log in

South Carolina wastewater permits expiring in 2028

Name: South Carolina NPDES permits expiring in 2028
Creator: Klarifi
License: https://klarifi.io/terms-of-service

5 NPDES permits · 6 MGD combined average flow

5 publicly owned wastewater treatment plants in South Carolina hold NPDES permits that expire during 2028, issued by South Carolina Department of Environmental Services. The table lists each plant with its permit number, expiry month, average flow, treatment technology and three-year violation count, in order of expiry.

An NPDES permit runs for five years. To keep discharging, a plant must apply for renewal at least 180 days before the expiry date, and the renewed permit usually arrives with tighter effluent limits, new monitoring requirements or a compliance schedule. That is why the year a permit expires is the year a plant starts budgeting for upgrades: nutrient removal, disinfection, capacity or controls.

Other years:

2026 (16)2027 (10)All South Carolina NPDES permits →

Publicly owned wastewater treatment plants in South Carolina with NPDES permits expiring in 2028, from EPA ICIS-NPDES records. Refreshed on every release.
Facility	City	Avg flow (MGD)	NPDES permit	Expires	Violations (3y)
City Of Bennettsville Wastewater Treatment Plant	Bennettsville	1.44	SC0025178	Feb 2028	6
Gsw&sa/conway WWTP	Conway	3.11	SC0021733	Mar 2028	29
Gsw&sa Central WWTP	Conway	—	SC0049362	Mar 2028	0
Dillon Little Pee Dee	Dillon	1.19	SC0021776	Aug 2028	5
Harleyville Town Of	Harleyville	0.09	SC0038504	Dec 2028	103

South Carolina permit renewals in 2028: 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: NPDES permit · POTW · Biological nutrient removal · Tertiary treatment · MGD · Lift station · 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. “NPDES permits expiring in 2028: South Carolina plants.” Updated October 26, 2026. https://klarifi.io/facilities/south-carolina/permits-expiring/2028

Need a custom cut of the data for a state, a county or a list of plants? Email info@klarifi.io.

Try Klarifi for free

Create your own trial account and explore how Klarifi can help you.

Try for free