47 NPDES permits · 47 MGD combined average flow
47 publicly owned wastewater treatment plants in Oklahoma hold NPDES permits that expire during 2028, 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.
| Facility | City | Avg flow (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|
| South Coffeyville Pwa | South Coffeyville | 0.13 | OK0020117 | Jan 2028 | 89 |
| Clinton, City Of | Clinton | — | OK0031011 | Jan 2028 | 120 |
| Northside Wastewater Treatment Plant | Tulsa | 23.36 | OK0026221 | Feb 2028 | 19 |
| Fairland Pwa | Fairland | 0.04 | OK0021504 | Feb 2028 | 3 |
| Ada, City Of | Ada | — | OK0026115 | Feb 2028 | 3 |
| Asher Utility Development Auth | Asher | — | OK0027154 | Feb 2028 | 50 |
| Stillwater, City Of | Stillwater | 4.64 | OK0027057 | Mar 2028 | 12 |
| Drumright Utilities Trust | Drumright | 0.45 | OK0022501 | Mar 2028 | 2 |
| Salina Public Works Auth | Salina | 0.16 | OK0020338 | Apr 2028 | 1 |
| Pawnee | Pawnee | 0.12 | OK0026654 | Apr 2028 | 139 |
| Carnegie Public Works Auth. | Carnegie | 0.1 | OK0028401 | Apr 2028 | 1 |
| Konawa, City Of | Konawa | 0.04 | OK0021873 | Apr 2028 | 25 |
| Dewey Public Works Authority | Dewey | 0.34 | OK0022551 | May 2028 | 4 |
| Mannford Wwt | Mannford | 0.19 | OK0022802 | May 2028 | 0 |
| Jay Utilities Authority | Jay | 0.34 | OK0031976 | Jun 2028 | 73 |
| Porter WWTP | Porter | 0.03 | OK0027570 | Jun 2028 | 29 |
| Pittsburg Co Rwd #20 -- Carlton Landing WWTF | Eufaula | 0.03 | OK0100625 | Jun 2028 | 49 |
| Boynton Pwa | Boynton | — | OK0034347 | Jun 2028 | 0 |
| Collinsville, City Of | Collinsville | — | OK0027375 | Jun 2028 | 91 |
| Owasso Public Works Authority | Owasso | 2.98 | OK0020303 | Jul 2028 | 4 |
| Duncan Public Utilities Auth | Duncan | 1.37 | OK0026638 | Jul 2028 | 380 |
| Weatherford Public Works Authority | Weatherford | 1.11 | OK0021563 | Jul 2028 | 1 |
| Chandler Municipal Authority | Chandler | 0.18 | OK0027120 | Jul 2028 | 53 |
| Choctaw Co. Rw & Sd #1 | Grant | 0.05 | OK0037826 | Jul 2028 | 0 |
| Bluejacket Wwt | Bluejacket | — | OK0031771 | Jul 2028 | 69 |
| Wright Public Works Authority | Wright City | 0.03 | OK0032387 | Aug 2028 | 164 |
| Francis Wwt | Francis | 0.0015 | OK0036064 | Aug 2028 | 29 |
| Bokchito, City Of | Bokchito | — | OK0027014 | Aug 2028 | 84 |
| Panama Public Works Authority | Panama | 0.38 | OK0031054 | Sep 2028 | 15 |
| City Of Newkirk | Newkirk | 0.29 | OK0045951 | Sep 2028 | 17 |
| Weleetka Pwa | Weleetka | 0.1 | OK0028525 | Sep 2028 | 20 |
| Oakland Pwa | Oakland | 0.03 | OK0031933 | Sep 2028 | 107 |
| Pryor Creek WWTP | Pryor | 1.07 | OK0040479 | Oct 2028 | 4 |
| Eufaula Public Works Authority | Eufaula | 0.44 | OK0035611 | Oct 2028 | 22 |
| Davis, City Of | Davis | 0.37 | OK0021644 | Oct 2028 | 85 |
| Mustang Improvement Authority | Mustang | 1.37 | OK0026816 | Nov 2028 | 95 |
| Hugo Municipal Authority | Hugo | 1.11 | OK0028487 | Nov 2028 | 140 |
| Perry, City Of | Perry | 0.33 | OK0027448 | Nov 2028 | 1 |
| Kiefer Public Works Authority | Kiefer | 0.19 | OK0028771 | Nov 2028 | 115 |
| Kingston, Town Of | Kingston | 0.17 | OK0027774 | Nov 2028 | 31 |
| Hulbert Public Works Authority | Hulbert | 0.09 | OK0032328 | Nov 2028 | 30 |
| Frederick (east) Wwt | Frederick | 0.08 | OK0027189 | Nov 2028 | 1 |
| Keota Pwa | Keota | 0.00048 | OK0031186 | Nov 2028 | 123 |
| City Of Moore WWTP | Moore | 5.08 | OK0027391 | Dec 2028 | 3 |
| Talihina Pwa | Talihina | 0.15 | OK0028380 | Dec 2028 | 20 |
| Pawhuska, City Of | Pawhuska | 0.14 | OK0028274 | Dec 2028 | 4 |
| Clayton Pwa | Clayton | 0.04 | OK0029157 | Dec 2028 | 49 |
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 · Anaerobic digester · MGD · 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: Oklahoma wastewater plants.” Updated October 26, 2026. https://klarifi.io/facilities/oklahoma/permits-expiring/2028Need a custom cut of the data for a state, a county or a list of plants? Email info@klarifi.io.