Michigan wastewater permits expiring in 2027
43 NPDES permits · 72 MGD combined average flow
43 publicly owned wastewater treatment plants in Michigan hold NPDES permits that expire during 2027, issued by Michigan Department of Environment, Great Lakes, and Energy. 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) |
|---|---|---|---|---|---|---|
| Union Twp WWTP | Mt Pleasant | 1.33 | MI0055808 | May 2027 | Clarifiers, Carrousels / oxidation ditches | 0 |
| Jackson WWTP | Jackson | 10.52 | MI0023256 | Oct 2027 | Clarifiers, Uncovered lagoons, Biogas silos | 41 |
| Lansing WWTP | Lansing | 10.06 | MI0023400 | Oct 2027 | Clarifiers | 5 |
| East Lansing Wastewater Treatment Plant | East Lansing | 9.13 | MI0022853 | Oct 2027 | Clarifiers, Aerated lagoons, Biogas silos, Biogas balloons | 1 |
| City Of Port Huron Wastewater Treatment Plant | Port Huron | 6.03 | MI0023833 | Oct 2027 | Biogas balloons | 4 |
| Delta Twp WWTP | Lansing | 3.87 | MI0022799 | Oct 2027 | Clarifiers, Biogas silos, Biogas balloons | 4 |
| Martin Rtb | Saint Clair Shores | 3.02 | MI0025453 | Oct 2027 | — | 0 |
| Marquette WWTP | Marquette | 2.62 | MI0023531 | Oct 2027 | Biogas silos, Biogas balloons | 24 |
| Portage Lake Authority WWTP | Houghton | 2.05 | MI0020061 | Oct 2027 | Clarifiers, Biogas silos, Biogas balloons | 9 |
| Southern Clinton Co WWTP | De Witt | 2.05 | MI0021008 | Oct 2027 | Biogas silos | 30 |
| Delhi Twp WWTP | Holt | 1.85 | MI0022781 | Oct 2027 | Clarifiers, Biogas silos | 0 |
| Cadillac WWTP | Cadillac | 1.81 | MI0020257 | Oct 2027 | Clarifiers, Biogas silos | 18 |
| Dowagiac WWTP | Dowagiac | 1.53 | MI0022837 | Oct 2027 | Clarifiers, Uncovered lagoons, Biogas silos | 5 |
| Greenville WWTP | Greenville | 1.48 | MI0020397 | Oct 2027 | Clarifiers, Biogas balloons | 29 |
| Grosse Ile Twp WWTP | Grosse Ile | 1.4 | MI0026191 | Oct 2027 | Clarifiers | 11 |
| Wixom WWTP | Wixom | 1.39 | MI0024384 | Oct 2027 | Clarifiers, Carrousels / oxidation ditches, Biogas silos | 14 |
| St Clair County-Algonac WWTP | Algonac | 1.35 | MI0020389 | Oct 2027 | Clarifiers, Biogas silos, Biogas balloons | 0 |
| Menominee WWTP | Menominee | 1.26 | MI0025631 | Oct 2027 | Clarifiers, Biogas silos | 5 |
| Howell WWTP | Howell | 1.14 | MI0021113 | Oct 2027 | Clarifiers, Biogas silos | 39 |
| Bridgeport Twp WWTP | Bridgeport | 0.97 | MI0022446 | Oct 2027 | Clarifiers, Carrousels / oxidation ditches, Biogas silos, Biogas balloons | 0 |
| Mason WWTP | Mason | 0.84 | MI0020435 | Oct 2027 | Clarifiers, Biogas silos | 31 |
| Grand Ledge WWTP | Grand Ledge | 0.77 | MI0020800 | Oct 2027 | Clarifiers | 37 |
| Flushing WWTP | Flushing | 0.66 | MI0020281 | Oct 2027 | Clarifiers, Biogas silos, Biogas balloons | 27 |
| Paw Paw Lake Area WWTP | Coloma | 0.61 | MI0023779 | Oct 2027 | Clarifiers | 0 |
| Northfield Twp WWTP | Whitmore Lake | 0.61 | MI0023710 | Oct 2027 | Clarifiers, Biogas silos, Biogas balloons | 3 |
| Tecumseh WWTP | Tecumseh | 0.6 | MI0020583 | Oct 2027 | Clarifiers, Aerated lagoons | 67 |
| St Louis WWTP | St. Louis | 0.59 | MI0021555 | Oct 2027 | Clarifiers, Uncovered lagoons, Carrousels / oxidation ditches, Biogas silos | 9 |
| Reed City WWTP | Reed City | 0.49 | MI0020036 | Oct 2027 | Biogas balloons | 11 |
| Fowlerville WWTP | Fowlerville | 0.47 | MI0020664 | Oct 2027 | Clarifiers, Uncovered lagoons, Carrousels / oxidation ditches | 3 |
| Williamston WWTP | Williamston | 0.28 | MI0021717 | Oct 2027 | Clarifiers, Biogas silos | 5 |
| Caro WWTP | Caro | 0.26 | MI0022551 | Oct 2027 | Clarifiers, Carrousels / oxidation ditches, Biogas balloons | 8 |
| Vassar WWTP | Vassar | 0.26 | MI0024252 | Oct 2027 | — | 4 |
| Leslie WWTP | Leslie | 0.22 | MI0020796 | Oct 2027 | Clarifiers, Carrousels / oxidation ditches | 40 |
| Dimondale/windsor WWTP | Dimondale | 0.17 | MI0053562 | Oct 2027 | Clarifiers, Carrousels / oxidation ditches | 2 |
| Hartford WWTP | Hartford | 0.12 | MI0023094 | Oct 2027 | Clarifiers | 51 |
| Otter Lake WWTP | Otter Lake | 0.0099 | MI0056979 | Oct 2027 | Clarifiers, Carrousels / oxidation ditches | 15 |
| Cass City WWTP | Cass City | — | MI0022594 | Oct 2027 | Clarifiers, Uncovered lagoons | 3 |
| City Of Newaygo WWTP | Newaygo | — | MI0048577 | Oct 2027 | Aerated lagoons, Uncovered lagoons | 0 |
| Columbiaville Wwsl | Columbiaville | — | MI0054810 | Oct 2027 | Aerated lagoons, Uncovered lagoons | 34 |
| Denton Township | Prudenville | — | MI0053317 | Oct 2027 | Aerated lagoons, Uncovered lagoons | 2 |
| Homer Wwsl | Homer | — | MI0060319 | Oct 2027 | Aerated lagoons, Uncovered lagoons | 0 |
| Howard City WWTP | Howard City | — | MI0053406 | Oct 2027 | Aerated lagoons, Uncovered lagoons | 10 |
| Lakeview WWTP | Lakeview | — | MI0023388 | Oct 2027 | Aerated lagoons, Uncovered lagoons | 7 |
Michigan 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 September 11, 2026.