Minnesota wastewater permits expiring in 2026
27 NPDES permits · 13 MGD combined average flow
27 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 | Technology | Violations (3y) |
|---|---|---|---|---|---|---|
| Nkasd WWTP | International Falls | 0.55 | MN0020257 | Feb 2026 | — | 5 |
| Brownsdale WWTP | Brownsdale | — | MN0022934 | Feb 2026 | Uncovered lagoons | 1 |
| Cromwell-Combined Discharge 1 | Cromwell | — | MN0051101 | Feb 2026 | Uncovered lagoons | 29 |
| Rogers WWTP | Rogers | 1.09 | MN0029629 | Mar 2026 | Aerated lagoons, Uncovered lagoons, Carrousels / oxidation ditches, Biogas balloons | 5 |
| Bemidji WWTP | Bemidji | 1.09 | MN0022462 | Mar 2026 | Biogas silos, Biogas balloons | 0 |
| Virginia WWTP | Virginia | 0.94 | MN0030163 | Mar 2026 | Biogas balloons | 1 |
| Delft Sanitary District WWTP | Windom | 0.0021 | MN0066541 | Mar 2026 | Uncovered lagoons | 4 |
| Breckenridge WWTP | Breckenridge | — | MN0022900 | Mar 2026 | Uncovered lagoons | 5 |
| Maynard WWTP | Maynard | 0.06 | MN0056588 | Apr 2026 | Aerated lagoons, Uncovered lagoons | 6 |
| Barnesville WWTP | Barnesville | — | MN0022501 | Apr 2026 | Uncovered lagoons | 54 |
| Owatonna WWTP | Owatonna | 3.16 | MN0051284 | May 2026 | Clarifiers, Biogas silos, Biogas balloons | 9 |
| Royalton WWTP | Motley | 0.24 | MN0024244 | May 2026 | Aerated lagoons, Uncovered lagoons | 18 |
| Sherburn WWTP | Sherburn | 0.19 | MN0024872 | May 2026 | Biogas balloons | 19 |
| St Leo WWTP | St. Leo | — | MN0024775 | May 2026 | Uncovered lagoons | 1 |
| East Lake Sewage Lagoon | East Lake | — | MN0058611 | Jun 2026 | Uncovered lagoons | 0 |
| Moorhead Wastewater Treatment Facility | Moorhead | 3.82 | MN0049069 | Jun 2026 | Uncovered lagoons, Biogas silos, Biogas balloons | 0 |
| Saint Francis WWTP | Saint Francis | 0.39 | MN0021407 | Jun 2026 | Uncovered lagoons, Biogas balloons | 8 |
| Aurora WWTP | Aurora | 0.26 | MN0020494 | Jun 2026 | Uncovered lagoons, Biogas silos, Biogas balloons | 8 |
| Roseau WWTP | Roseau | 0.5 | MN0024643 | Aug 2026 | — | 11 |
| Lansing Township | Lansing | — | MN0063461 | Aug 2026 | Uncovered lagoons | 3 |
| Thief River Falls WWTP | Thief River Falls | — | MN0021431 | Aug 2026 | Uncovered lagoons | 29 |
| Hector-Treatment Plant | Hector | 0.22 | MN0025445 | Sep 2026 | Uncovered lagoons, Biogas balloons | 9 |
| Wanamingo | Wanamingo | 0.15 | MN0022209 | Nov 2026 | Biogas balloons | 20 |
| Balaton WWTP | Balaton | — | MN0020559 | Nov 2026 | Uncovered lagoons | 8 |
| Borup WWTP | Borup | — | MN0022853 | Nov 2026 | Uncovered lagoons | 23 |
| Green Lake Sswd | Spicer | 0.6 | MN0052752 | Dec 2026 | Biogas balloons | 0 |
| Garvin WWTP | Garvin | — | MN0029602 | Dec 2026 | Uncovered lagoons | 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 September 11, 2026.