Wisconsin wastewater permits expiring in 2026
12 NPDES permits · 43 MGD combined average flow
12 publicly owned wastewater treatment plants in Wisconsin hold NPDES permits that expire during 2026, issued by Wisconsin Department of Natural Resources. 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) |
|---|---|---|---|---|---|
| Port Washington WWTP | Port Washington | 1.5 | WI0020460 | Mar 2026 | 20 |
| Jefferson Wastewater Treatment | Jefferson | 1.17 | WI0024333 | Mar 2026 | 0 |
| Reeseville Wastewater Treatment Facility | Reeseville | 0.19 | WI0028509 | Mar 2026 | 17 |
| Crivitz Wastewater Treatment Facility | Crivitz | 0.11 | WI0060372 | Mar 2026 | 1 |
| Cashton Wastewater Treatment Facility | Cashton | 0.1 | WI0020915 | Mar 2026 | 0 |
| Lowell Wastewater Treatment Facility | Lowell | 0.03 | WI0029271 | Mar 2026 | 0 |
| Wauzeka Wastewater Treatment Facility | Wauzeka | 0.03 | WI0022276 | Mar 2026 | 0 |
| Burnett Sanitary District #1 WWTF | Burnett | 0.01 | WI0031551 | Mar 2026 | 1 |
| Grand View Sanitary District | Grand View | — | WI0035131 | Mar 2026 | 25 |
| Sheboygan Wastewater Treatment Plant | Sheboygan | — | WI0025411 | Mar 2026 | 1 |
| EPA Superfund Site: Madison Metropolitan Sewerage District Lagoons | Madison | 39.37 | WIG009756 | Sep 2026 | 2 |
| Rhinelander Water & Wastewater-Bg544 | Rhinelander | 0.94 | WI0020044 | Dec 2026 | 0 |
Wisconsin 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 · MGD · Lift station · 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: Wisconsin wastewater plants.” Updated October 26, 2026. https://klarifi.io/facilities/wisconsin/permits-expiring/2026Need a custom cut of the data for a state, a county or a list of plants? Email info@klarifi.io.