Michigan wastewater permits expiring in 2026
26 NPDES permits · 94 MGD combined average flow
26 publicly owned wastewater treatment plants in Michigan hold NPDES permits that expire during 2026, 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 | Violations (3y) |
|---|---|---|---|---|---|
| Southgate-Wyandotte Cso Rtf | Wyandotte | 34.9 | MI0036072 | Oct 2026 | 2 |
| Milk River Cso Rtb | Grosse Pointe Woods | 26.28 | MI0025500 | Oct 2026 | 46 |
| Alpena WWTP | Alpena | 3.71 | MI0022195 | Oct 2026 | 9 |
| Cbpu Waste Water Treatment Plant | Coldwater | 3.54 | MI0020117 | Oct 2026 | 10 |
| Owosso/mid Shiawassee Co WWTP | Owosso | 3.53 | MI0023752 | Oct 2026 | 29 |
| Ithaca Wwsl | Ithaca | 2.58 | MI0056928 | Oct 2026 | 35 |
| Zeeland WWTP | Zeeland | 2.29 | MI0020524 | Oct 2026 | 8 |
| Commerce Twp WWTP | Walled Lake | 2.25 | MI0025071 | Oct 2026 | 0 |
| Oakland Co Walled Lk Novi WWTP | Novi | 2.21 | MI0024287 | Oct 2026 | 0 |
| Cheboygan WWTP | Cheboygan | 1.5 | MI0020303 | Oct 2026 | 16 |
| Genoa-Oceola WWTP | Howell | 1.4 | MI0055654 | Oct 2026 | 1 |
| Three Rivers WWTP | Three Rivers | 1.26 | MI0020991 | Oct 2026 | 45 |
| Sturgis WWTP | Sturgis | 1.14 | MI0020451 | Oct 2026 | 1 |
| St Clair WWTP | St Clair | 0.99 | MI0020591 | Oct 2026 | 0 |
| Belding WWTP | Belding | 0.98 | MI0020851 | Oct 2026 | 48 |
| Holly WWTP | Holly | 0.91 | MI0020184 | Oct 2026 | 67 |
| Oakland Co-Acacia Park Cso | Beverly Hills | 0.87 | MI0037427 | Oct 2026 | 0 |
| Chelsea WWTP | Chelsea | 0.84 | MI0020737 | Oct 2026 | 0 |
| Rogers City WWTP | Rogers City | 0.63 | MI0057813 | Oct 2026 | 5 |
| Standish WWTP | Standish | 0.49 | MI0024139 | Oct 2026 | 13 |
| Chesaning WWTP | Chesaning | 0.46 | MI0020087 | Oct 2026 | 6 |
| Hudson WWTP | Hudson | 0.32 | MI0021377 | Oct 2026 | 0 |
| Howell Twp WWTP | Howell | 0.31 | MI0055727 | Oct 2026 | 3 |
| Jonesville WWTP | Jonesville | 0.27 | MI0020109 | Oct 2026 | 1 |
| Luna Pier WWTP | Luna Pier | 0.24 | MI0058821 | Oct 2026 | 2 |
| Salem Twp WWTP | Salem | 0.02 | MI0054798 | Oct 2026 | 14 |
Michigan 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 · Ozonation · Activated sludge · 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: Michigan wastewater plants.” Updated October 26, 2026. https://klarifi.io/facilities/michigan/permits-expiring/2026Need a custom cut of the data for a state, a county or a list of plants? Email info@klarifi.io.