Wisconsin NPDES permit search
Status, expiry and violations for 394 municipal wastewater permits · issued by WDNR as WPDES permits
In short
How do I look up an NPDES permit in Wisconsin?
Search this page by permit number or plant name for a municipal plant’s permit status, expiry date and violations. For the official file, search DNR’s Permits on the Web or DNR’s list of permits on public notice. EPA’s ECHO database shows the monitoring results and violations of every permit. The 414 industrial permits in Wisconsin are listed in Klarifi with a free account.
Links to official sources checked September 2026.
Effective
6
Administratively continued
38
Expired
350
Plants with effluent violations, 3 years
254
Where to find official Wisconsin NPDES records
Wisconsin Department of Natural Resources (WDNR) runs the NPDES program in Wisconsin under authorization from EPA Region 5, as the Wisconsin Pollutant Discharge Elimination System (WPDES). It issues and enforces the permits and keeps the official file: applications, permits, fact sheets and monitoring reports. EPA issues the permits on tribal lands. WDNR website ↗
permits · permit documents
DNR’s WPDES permit search. Enter the permit number or the permittee’s name to list the documents of a final individual wastewater permit: the permit, its fact sheet and most supporting documents.
permit documents
A table of the permits on public notice, linking each proposed permit, its notice and its fact sheet.
permits · DMRs · inspections · violations · enforcement
EPA’s Enforcement and Compliance History Online. Search water facilities by permit number, name or city; the Detailed Facility Report lists inspections, violations and enforcement actions, and Effluent Charts plot monitoring results against the permit limits.
- Permit numbers
- DNR writes WPDES numbers with a prefix and two suffixes, such as WI-0021725-11-0 for Galesville, whose EPA number is WI0021725.
- Discharge monitoring reports
- Through DNR’s own electronic DMRs, reached from DNR Switchboard, not NetDMR.
Industrial and commercial NPDES permits in Wisconsin
Most NPDES permits are not held by municipal plants. EPA’s permit database lists 414 individual permits in force for industrial and commercial facilities in Wisconsin (manufacturers, food processors, mines, power plants, landfills), 65 of them major dischargers, plus 58 facilities covered by a general permit, mostly for stormwater. 14 of the individual permits recorded at least one effluent violation in the last three years.
| Facility | Permit | Status | Expires | Effluent violations |
|---|
Unlock 414 industrial permits in Wisconsin
Search every industrial and commercial discharger in Wisconsin by name or permit number, with permit status, expiry and violation history. Free with a Klarifi account.
Industrial and commercial NPDES permits in Wisconsin: permits in force (effective or administratively continued) held by facilities EPA does not class as publicly owned treatment works or federal facilities. Source: EPA ICIS-NPDES via Klarifi, October 2026.
Violations at Wisconsin wastewater plants
254 of the 394 municipal plants on this page recorded at least one effluent violation, a monitored value above a permit limit, in the last three years, and 272 had a violation of any kind, including late or missing monitoring reports. Each plant’s page shows its own count. EPA’s enforcement records list 32 formal cases naming Wisconsin wastewater plants, 15 of them since fiscal year 2020, with $297,674 in penalties assessed. Enforcement cases in Wisconsin →
Permit renewals by year
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.
Largest permit holders in Wisconsin
| Facility | City | Avg flow (MGD) | Design (MGD) | NPDES permit | Status | Expires | Violations (3y) |
|---|---|---|---|---|---|---|---|
| Milwaukee Metro Sew Dist Combi | Milwaukee | 103.5 | 123 | WI0036820 | Expired | Mar 2024 | 392 |
| EPA Superfund Site: Madison Metropolitan Sewerage District Lagoons | Madison | 39.37 | — | WIG009756 | Administratively continued | Sep 2026 | 2 |
| Green Bay Metropolitan Sewerage District | Green Bay | 36.81 | — | WIL065251 | Effective | Dec 2030 | 7 |
| Racine Wastewater Treatment Facility | Racine | 20.89 | 30 | WI0025194 | Expired | Sep 2019 | 6 |
| Kenosha Water Utility Wastewater Treatment Plant | Kenosha | — | 28 | WI0028703 | Expired | Dec 2023 | 2 |
| La Crosse City | La Crosse | 10.21 | 20 | WI0029581 | Administratively continued | Dec 2020 | 0 |
| Oshkosh Wastewater Treatment F | Oshkosh | 10.56 | 20 | WI0025038 | Expired | Dec 2023 | 33 |
| Sheboygan Wastewater Treatment Plant | Sheboygan | — | 18.39 | WI0025411 | Expired | Mar 2026 | 1 |
| Neenah-Menasha Sewerage Commission WWTF | Menasha | 12.33 | 18 | WI0026085 | Expired | Jun 2022 | 194 |
| Janesville Wastewater Utility | Janesville | 11.03 | 17.18 | WI0030350 | Expired | Jun 2025 | 0 |
Wisconsin NPDES permits: questions
NPDES permit search in other states
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 12, 2026.
Wastewater terms: NPDES permit · POTW · Significant industrial user · MGD · FOG · Equalization tank · all terms