F0/100
FOND DU LAC WATERWORKS — Water Quality Report 2026
Serving 44,303 people · Wisconsin
Water Source
Groundwater
County
—
System ID
WI4200469
Violations
112
Contaminant Test Results
3 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 1.48 mg/L | 1.30 mg/L | Over Limit |
strontium | 11643.16 µg/L | — | Above Goal |
Lead (90th percentile) | 0.008 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
2
Violations (last 5yr)
0
Unresolved
1
Health-Related
TIER 2Resolved
Treatment technique violation
When: October 17, 2024 – March 25, 2025Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Disinfection byproduct treatment technique failure
When: October 17, 2024 – June 12, 2025Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
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 FOND DU LAC WATERWORKS
Is FOND DU LAC WATERWORKS water safe to drink?
FOND DU LAC WATERWORKS water receives a grade of F (0/100), which is considered failing. 1 contaminant(s) exceed EPA legal limits and 112 violation(s) are on record. Customers may want to consider using a water filter.
What contaminants has FOND DU LAC WATERWORKS detected?
67 contaminants were tested in FOND DU LAC WATERWORKS's water. Notable contaminants include Copper (90th percentile), Lead (90th percentile), strontium. 1 exceed EPA legal limits (MCLs). 3 exceed EPA health goals (MCLGs).
Does FOND DU LAC WATERWORKS have any EPA violations?
Yes, FOND DU LAC WATERWORKS has 112 EPA violation(s) on record, with the most recent in 2024. Violation types include TT, Other, MR. 23 are health-based violations.
How many people does FOND DU LAC WATERWORKS serve?
FOND DU LAC WATERWORKS serves approximately 44,303 people, Wisconsin. The system provides water to 1 community: Fond Du Lac.
What type of water does FOND DU LAC WATERWORKS provide?
FOND DU LAC WATERWORKS sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is WI4200469.
How does FOND DU LAC WATERWORKS compare to other utilities in Wisconsin?
FOND DU LAC WATERWORKS scores 0/100 with a grade of F (failing). This score suggests significant water quality concerns relative to other utilities. Visit our Wisconsin state page for a full comparison of water systems.