182 plants · 60% of the state · 152 MGD reported by 54 plants
Klarifi identifies 182 publicly owned wastewater treatment plants with lagoon systems in Michigan, 60% of the 305 plants in the state (152 MGD reported by 54 plants). The largest is City Of Grand Rapids Wastewater Treatment Plant in Grand Rapids at 33.4 MGD.
Lagoon systems treat wastewater in large earthen ponds over weeks of retention time, with or without mechanical aeration. They serve thousands of small towns because they are cheap to run, but they struggle with ammonia and nutrient limits, fill with sludge over decades and are the plants most often converted or upgraded when a permit is renewed.
| # | Facility | City | Avg flow (MGD) | NPDES permit | Expires | Violations (3y) |
|---|---|---|---|---|---|---|
| 1 | City Of Grand Rapids Wastewater Treatment Plant | Grand Rapids | 33.4 | MI0026069 | Oct 2029 | 9 |
| 2 | Anthony Ragnone Wastewater Treatment Plant | Montrose | 23.04 | MI0022977 | Oct 2023 | 3 |
| 3 | City Of Wyoming Clean Water Plant | Grandville | 14.38 | MI0024392 | Oct 2030 | 74 |
| 4 | City Of Saginaw Wastewater Treatment Plant | Saginaw | 13.41 | MI0025577 | Oct 2029 | 21 |
| 5 | Clinton River WRRF | Pontiac | 10.99 | MI0023825 | Oct 2025 | 3 |
| 6 | Jackson WWTP | Jackson | 10.52 | MI0023256 | Oct 2027 | 41 |
| 7 | East Lansing Wastewater Treatment Plant | East Lansing | 9.13 | MI0022853 | Oct 2027 | 1 |
| 8 | Saginaw Twp WWTP | Saginaw | 3.24 | MI0023973 | Oct 2028 | 10 |
| 9 | Cbpu Waste Water Treatment Plant | Coldwater | 3.2 | MI0020117 | Oct 2026 | 9 |
| 10 | Sault Ste. Marie Wastewater Treatment Plant | Sault Sainte Marie | 2.27 | MI0024058 | Oct 2025 | 21 |
| 11 | Commerce Twp WWTP | Walled Lake | 2.13 | MI0025071 | Oct 2026 | 0 |
| 12 | Coopersville WWTP | Coopersville | 1.94 | MI0022730 | Oct 2025 | 3 |
| 13 | Houghton Lake WWTP | Houghton Lake | 1.64 | MI0028312 | Oct 2022 | 2 |
| 14 | Leoni Twp WWTP | Michigan Center | 1.62 | MI0045942 | Oct 2028 | 1 |
| 15 | Kalamazoo Lake WWTP | Saugatuck | 1.6 | MI0056324 | Oct 2025 | 66 |
| 16 | Dowagiac WWTP | Dowagiac | 1.53 | MI0022837 | Oct 2027 | 5 |
| 17 | Ludington WWTP | Ludington | 1.51 | MI0021334 | Oct 2025 | 30 |
| 18 | Tittabawassee Twp WWTP | Freeland | 1.16 | MI0027383 | Oct 2028 | 1 |
| 19 | Sturgis WWTP | Sturgis | 1.13 | MI0020451 | Oct 2026 | 2 |
| 20 | Alma Wastewater Treatment Plant | Alma | 1.01 | MI0020265 | Oct 2028 | 0 |
| 21 | South Lyon WWTP | South Lyon | 0.97 | MI0020273 | Oct 2028 | 11 |
| 22 | Brighton WWTP | Brighton | 0.94 | MI0020877 | Oct 2025 | 8 |
| 23 | Cheboygan WWTP | Cheboygan | 0.84 | MI0020303 | Oct 2026 | 16 |
| 24 | New Baltimore WWTP | New Baltimore | 0.83 | MI0023680 | Oct 2029 | 0 |
| 25 | Buena Vista Twp WWTP | Saginaw | 0.79 | MI0022497 | Oct 2023 | 57 |
Contacts and project signals for every plant on this list
Klarifi adds verified decision-maker contacts, permit limits, discharge monitoring data and the capital projects planned in each city, filterable by technology, size and compliance record.
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.