Oconomowoc Wastewater Treatment Plnt
Oconomowoc, WI · Waukesha County · Publicly Owned Treatment Works
- Average flow
- —
- Design flow
- 4 MGD
- NPDES permit
- WI0021181
- Expired
- Permit expires
- September 2025
- Population served
- 21,024
- CWNS 2022
Oconomowoc Wastewater Treatment Plnt is a publicly owned wastewater treatment works in Oconomowoc, Waukesha County, Wisconsin, serving about 21,024 residents. Treatment on site includes clarifiers, biogas silos. It discharges under NPDES permit WI0021181 (expired), which expires in September 2025, with 1 recorded violation in the last three years.
Treatment technology
Treatment structures identified at this facility. Exact unit counts are available in Klarifi.
Compliance snapshot (last 3 years)
- Total violations
- 1
- Effluent violations
- 1
Based on NPDES Discharge Monitoring Reports. Full violation history, parameters and discharge data available in the Klarifi platform.
Key contacts
25 verified contacts for Oconomowoc Wastewater Treatment Plnt, with validated emails and direct phone numbers.
Unlock 25 verified contacts (22 more than shown)
Names, validated emails and direct phone numbers for decision-makers at Oconomowoc Wastewater Treatment Plnt, plus the full compliance history and discharge data.
Nearby wastewater treatment plants in Wisconsin
Ixonia · 6 mi away
—
Delafield · 6 mi away
2.33 MGD
Dousman · 6 mi away
0.48 MGD
Ashippun · 8 mi away
0.09 MGD
Lebanon · 12 mi away
0.05 MGD
Watertown · 13 mi away
2.81 MGD
Waukesha · 15 mi away
3.15 MGD
Sussex · 15 mi away
2.57 MGD
Oconomowoc Wastewater Treatment Plnt: frequently asked 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; facility record last updated March 6, 2025.