Williams Bay Waterworks
Williams Bay Waterworks (EPA ID WI2650060) in Williams Bay, WI supplies groundwater (wells) to about 2,601 people: 1 violation since 2016, latest lead result 45 ppb, PFAS not tested.
Health-based violations since 2016: Lead and Copper Rule. All are listed as resolved.
The 90th-percentile lead level in the latest round (Jan 2026) was above EPA's 15 ppb action level, which requires the utility to take further steps.
This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5 covers systems serving over 3,300 people and a sample of smaller ones).
Service area
EPA service-area boundary (state-supplied or EPA-modeled)System facts
Health-based violations
| Contaminant or rule | Health-based violations since 2016 |
|---|---|
| Lead and Copper Rule | 1 |
A health-based violation means a contaminant exceeded its legal limit (MCL) or a required treatment technique was not met, as reported by the state to EPA’s SDWIS. All are listed as resolved or archived; the latest began Jul 2025.
Lead
90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.
PFAS
This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5).
ZIP codes served
ZIP codes whose center lies in this system’s service area.
What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.
Questions
Has Williams Bay Waterworks had drinking water violations?
Health-based violations since 2016: Lead and Copper Rule. All are listed as resolved.
What is the lead level in Williams Bay Waterworks water?
The latest 90th-percentile lead result (Jan 2026) was 45 ppb. EPA’s action level is 15 ppb (10 ppb from 2027).
Does Williams Bay Waterworks have PFAS in its water?
This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5 covers systems serving over 3,300 people and a sample of smaller ones).