How many wastewater permits expire in Oregon in 2026?

9 NPDES permits held by publicly owned wastewater treatment plants in Oregon expire in 2026, covering a combined average flow of 29 MGD. The busiest month is Aug 2026 with 6 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 Oregon in 2026?

Medford Rwrf in Central Point, treating about 16.52 MGD under permit OR0026263, expiring Jul 2026.

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.

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Oregon wastewater permits expiring in 2026

Name: Oregon NPDES permits expiring in 2026
Creator: Klarifi
License: https://klarifi.io/terms-of-service

9 NPDES permits · 29 MGD combined average flow

9 publicly owned wastewater treatment plants in Oregon hold NPDES permits that expire during 2026, issued by Oregon Department of Environmental Quality. 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:

2027 (19)2028 (10)All Oregon NPDES permits →

Publicly owned wastewater treatment plants in Oregon with NPDES permits expiring in 2026, from EPA ICIS-NPDES records. Refreshed on every release.
Facility	City	Avg flow (MGD)	NPDES permit	Expires	Violations (3y)
Medford Rwrf	Central Point	16.52	OR0026263	Jul 2026	1
Dayville STP	Dayville	0.01	OR0041505	Jul 2026	52
Gresham WWTP	Portland	11.55	OR0026131	Aug 2026	0
Aumsville STP	Aumsville	0.65	OR0022721	Aug 2026	5
Yoncalla WTP	Yoncalla	0.21	OR0022454	Aug 2026	27
Brooks Sewage Treatment Plant	Brooks	0.19	OR0033049	Aug 2026	7
Huntington STP	Huntington	0.15	OR0020052	Aug 2026	300
Heppner STP	Heppner	0.13	OR0020770	Aug 2026	1
Port Orford STP	Port Orford	—	OR0020516	Nov 2026	11

Oregon permit renewals in 2026: 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 · Ozonation · Activated sludge · 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 2026: Oregon wastewater plants.” Updated October 26, 2026. https://klarifi.io/facilities/oregon/permits-expiring/2026

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

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