Oregon wastewater permits expiring in 2027
19 NPDES permits · 10 MGD combined average flow
19 publicly owned wastewater treatment plants in Oregon hold NPDES permits that expire during 2027, 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.
| Facility | City | Avg flow (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|
| Ashland WWTP | Ashland | 1.67 | OR0026255 | Jan 2027 | 13 |
| Glendale WWTP | Glendale | 0.1 | OR0022730 | Jan 2027 | 4 |
| Rainbow Rock STP | Brookings | 0.0031 | OR0030945 | Jan 2027 | 1 |
| Arch Cape STP | Arch Cape | 0.13 | OR0027499 | Feb 2027 | 0 |
| Maupin STP | Maupin | 0.06 | OR0022608 | Feb 2027 | 121 |
| Oak Lodge Water Reclamation Facility | Milwaukie | 3.05 | OR0026140 | Mar 2027 | 3 |
| Monroe STP | Monroe | 0.17 | OR0029203 | Apr 2027 | 13 |
| Cave Junction Wastewater Treatment Facility | Cave Junction | 0.28 | OR0028339 | May 2027 | 8 |
| Aurora Sewage Treatment Plant | Aurora | 0.09 | OR0043991 | May 2027 | 11 |
| Independence STP | Independence | 1.02 | OR0020443 | Aug 2027 | 10 |
| Harrisburg Lagoon Treatment Plant | Harrisburg | 0.8 | OR0033260 | Aug 2027 | 0 |
| Dundee STP | Dundee | 0.33 | OR0023388 | Aug 2027 | 1 |
| Hubbard STP | Hubbard | 0.21 | OR0020591 | Aug 2027 | 11 |
| Creswell STP | Creswell | — | OR0027545 | Sep 2027 | 42 |
| Stanfield STP | Stanfield | — | OR0026972 | Sep 2027 | 24 |
| Rockaway Beach STP | Rockaway Beach | 0.29 | OR0023302 | Oct 2027 | 0 |
| Canby WWTP | Canby | 0.98 | OR0020214 | Nov 2027 | 0 |
| Twin Rocks WWTP | Rockaway Beach | 0.15 | OR0023493 | Nov 2027 | 2 |
| Umatilla STP | Umatilla | 0.67 | OR0022306 | Dec 2027 | 0 |
Oregon 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 · Activated sludge · Oxidation ditch · 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: Oregon wastewater plants.” Updated October 26, 2026. https://klarifi.io/facilities/oregon/permits-expiring/2027Need a custom cut of the data for a state, a county or a list of plants? Email info@klarifi.io.