Minnesota wastewater permits expiring in 2026
28 NPDES permits · 23 MGD combined average flow
28 publicly owned wastewater treatment plants in Minnesota hold NPDES permits that expire during 2026, issued by Minnesota Pollution Control Agency. 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) |
|---|---|---|---|---|---|
| Nkasd WWTP | International Falls | 0.75 | MN0020257 | Feb 2026 | 5 |
| Brownsdale WWTP | Brownsdale | — | MN0022934 | Feb 2026 | 1 |
| Cromwell-Combined Discharge 1 | Cromwell | — | MN0051101 | Feb 2026 | 21 |
| Rogers WWTP | Rogers | 1.16 | MN0029629 | Mar 2026 | 5 |
| Virginia WWTP | Virginia | 1.03 | MN0030163 | Mar 2026 | 1 |
| Bemidji WWTP | Bemidji | 1.02 | MN0022462 | Mar 2026 | 0 |
| Delft Sanitary District WWTP | Windom | 0.0021 | MN0066541 | Mar 2026 | 4 |
| Breckenridge WWTP | Breckenridge | — | MN0022900 | Mar 2026 | 5 |
| Barnesville WWTP | Barnesville | 1.26 | MN0022501 | Apr 2026 | 98 |
| Detroit Lakes WWTP | Detroit Lakes | 1.04 | MN0020192 | Apr 2026 | 3 |
| Maynard WWTP | Maynard | 0.04 | MN0056588 | Apr 2026 | 6 |
| Owatonna WWTP | Owatonna | 3.32 | MN0051284 | May 2026 | 10 |
| Royalton WWTP | Motley | 0.28 | MN0024244 | May 2026 | 18 |
| Sherburn WWTP | Sherburn | 0.19 | MN0024872 | May 2026 | 19 |
| St Leo WWTP | St. Leo | — | MN0024775 | May 2026 | 1 |
| East Lake Sewage Lagoon | East Lake | — | MN0058611 | Jun 2026 | 0 |
| Moorhead Wastewater Treatment Facility | Moorhead | 3.8 | MN0049069 | Jun 2026 | 0 |
| Saint Francis WWTP | Saint Francis | 0.38 | MN0021407 | Jun 2026 | 9 |
| Aurora WWTP | Aurora | 0.24 | MN0020494 | Jun 2026 | 7 |
| Thief River Falls WWTP | Thief River Falls | 6.93 | MN0021431 | Aug 2026 | 29 |
| Roseau WWTP | Roseau | 0.5 | MN0024643 | Aug 2026 | 11 |
| Lansing Township | Lansing | — | MN0063461 | Aug 2026 | 3 |
| Hector-Treatment Plant | Hector | 0.25 | MN0025445 | Sep 2026 | 9 |
| Wanamingo | Wanamingo | 0.12 | MN0022209 | Nov 2026 | 15 |
| Balaton WWTP | Balaton | — | MN0020559 | Nov 2026 | 8 |
| Borup WWTP | Borup | — | MN0022853 | Nov 2026 | 6 |
| Green Lake Sswd | Spicer | 0.5 | MN0052752 | Dec 2026 | 0 |
| Garvin WWTP | Garvin | — | MN0029602 | Dec 2026 | 18 |
Minnesota 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 · 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 2026: Minnesota wastewater plants.” Updated October 26, 2026. https://klarifi.io/facilities/minnesota/permits-expiring/2026Need a custom cut of the data for a state, a county or a list of plants? Email info@klarifi.io.