How many wastewater permits expire in Oklahoma in 2027?

35 NPDES permits held by publicly owned wastewater treatment plants in Oklahoma expire in 2027, covering a combined average flow of 12 MGD. The busiest month is Jan 2027 with 8 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 Oklahoma in 2027?

Del City Municipal Svcs. Auth in Del City, treating about 1.9 MGD under permit OK0026085, expiring Jul 2027.

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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Oklahoma wastewater permits expiring in 2027

Name: Oklahoma NPDES permits expiring in 2027
Creator: Klarifi
License: https://klarifi.io/terms-of-service

35 NPDES permits · 12 MGD combined average flow

35 publicly owned wastewater treatment plants in Oklahoma hold NPDES permits that expire during 2027, issued by Oklahoma 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:

2026 (31)2028 (47)All Oklahoma NPDES permits →

Publicly owned wastewater treatment plants in Oklahoma with NPDES permits expiring in 2027, from EPA ICIS-NPDES records. Refreshed on every release.
Facility	City	Avg flow (MGD)	NPDES permit	Expires	Violations (3y)
Poteau, City Of	Poteau	1.7	OK0021610	Jan 2027	4
Bristow Municipal Authority	Bristow	0.41	OK0032549	Jan 2027	138
Stringtown Pwa	Stringtown	0.05	OK0030449	Jan 2027	32
Depew, Town Of	Depew	0.03	OK0021890	Jan 2027	29
Pensacola Pub Works Authority	Pensacola	0.0078	OK0040410	Jan 2027	7
Mounds Pwa Wwt	Mounds	0.00015	OK0022888	Jan 2027	7
Cyril, Town Of	Cyril	—	OK0041467	Jan 2027	14
Hobart Public Works Authority	Hobart	—	OK0028649	Jan 2027	0
Healdton Wwt	Healdton	0.13	OK0027413	Feb 2027	13
Oologah Public Works Authority	Oologah	0.04	OK0034223	Feb 2027	193
Guymon City Of	Guymon	0.96	OK0045713	Mar 2027	21
Newcastle Public Works Auth.	Newcastle	0.52	OK0028614	Mar 2027	92
Ochelata Utilities Authority	Ochelata	0.06	OK0034517	Mar 2027	88
Checotah WWTP	Checotah	0.41	OK0028100	Apr 2027	22
Fairfax Public Works Auth	Fairfax	0.16	OK0029017	Apr 2027	33
Seneca-Cayuga Tribe	Miami	0.03	OK0039098	Apr 2027	0
Perkins Wwt	Perkins	0.21	OK0028801	May 2027	151
Glenpool Wwt	Glenpool	0.87	OK0027138	Jun 2027	175
Morris, City Of -NW Plant	Morris	0.08	OK0028924	Jun 2027	38
Woodward, City Of	Woodward	—	OK0034509	Jun 2027	0
Del City Municipal Svcs. Auth	Del City	1.9	OK0026085	Jul 2027	8
Chickasaw Tribal Utilities Authority	Thackerville	0.46	OK0045721	Jul 2027	5
Madill Pwa	Madill	0.46	OK0031721	Jul 2027	331
Shidler, City Of	Shidler	0.13	OK0022993	Jul 2027	0
El Reno Municipal Authority	El Reno	1.13	OK0100382	Sep 2027	34
Nowata, City Of	Nowata	0.67	OK0025470	Sep 2027	21
Chouteau Pwa	Chouteau	0.27	OK0022764	Sep 2027	122
Cleveland South WWTP	Cleveland	0.18	OK0028347	Sep 2027	12
Roland, Town Of	Roland	0.38	OK0030392	Oct 2027	63
Wewoka Public Works Authority-Wewoka WTP	Wewoka	0.38	OK0022659	Oct 2027	196
Quapaw Pwa	Quapaw	0.1	OK0028258	Oct 2027	32
Calvin Pwa	Calvin	0.0039	OK0037818	Oct 2027	41
Dustin Public Works Authority	Dustin	—	OK0029050	Oct 2027	2
Grove Msa	Grove	0.61	OK0028886	Dec 2027	4
Cherokee Former City Hall	Cherokee	0.06	OK0020052	Dec 2027	34

Oklahoma permit renewals in 2027: 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 · Oxidation ditch · Anaerobic digester · 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 2027: Oklahoma wastewater plants.” Updated October 26, 2026. https://klarifi.io/facilities/oklahoma/permits-expiring/2027

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