B76/100
OCONOMOWOC WATERWORKS — Water Quality Report 2026
Serving 15,805 people · Wisconsin
Water Source
Groundwater
County
—
System ID
WI2680227
Violations
9
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.007 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2014.
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Frequently Asked Questions About OCONOMOWOC WATERWORKS
Is OCONOMOWOC WATERWORKS water safe to drink?
OCONOMOWOC WATERWORKS water receives a grade of B (76/100), which is considered good. Out of 66 contaminants tested, none exceed EPA legal limits. 1 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has OCONOMOWOC WATERWORKS detected?
66 contaminants were tested in OCONOMOWOC WATERWORKS's water. Notable contaminants include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).
Does OCONOMOWOC WATERWORKS have any EPA violations?
Yes, OCONOMOWOC WATERWORKS has 9 EPA violation(s) on record, with the most recent in 2014. Violation types include MR, Other, MCL. 3 are health-based violations.
How many people does OCONOMOWOC WATERWORKS serve?
OCONOMOWOC WATERWORKS serves approximately 15,805 people, Wisconsin. The system provides water to 1 community: Oconomowoc.
What type of water does OCONOMOWOC WATERWORKS provide?
OCONOMOWOC WATERWORKS sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is WI2680227.
How does OCONOMOWOC WATERWORKS compare to other utilities in Wisconsin?
OCONOMOWOC WATERWORKS scores 76/100 with a grade of B (good). This is an above-average performance for utilities statewide. Visit our Wisconsin state page for a full comparison of water systems.