B73/100
ST CHARLES — Water Quality Report 2026
Serving 33,103 people · Illinois
Water Source
Groundwater
County
—
System ID
IL0894830
Violations
9
Contaminant Test Results
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
strontium | 2510.50 µg/L | — | Above Goal |
Lead (90th percentile) | 0.006 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
1
Violation (last 5yr)
1
Unresolved
0
Health-Related
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 ST CHARLES
Is ST CHARLES water safe to drink?
ST CHARLES water receives a grade of B (73/100), which is considered good. Out of 66 contaminants tested, none exceed EPA legal limits. 2 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has ST CHARLES detected?
66 contaminants were tested in ST CHARLES's water. Notable contaminants include Lead (90th percentile), strontium. No contaminants exceed EPA legal limits. 2 exceed EPA health goals (MCLGs).
Does ST CHARLES have any EPA violations?
Yes, ST CHARLES has 9 EPA violation(s) on record, with the most recent in 2025. Violation types include Other, MR, MCL. 3 are health-based violations.
How many people does ST CHARLES serve?
ST CHARLES serves approximately 33,103 people, Illinois. The system provides water to 1 community: Saint Charles.
What type of water does ST CHARLES provide?
ST CHARLES sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is IL0894830.
How does ST CHARLES compare to other utilities in Illinois?
ST CHARLES scores 73/100 with a grade of B (good). This is an above-average performance for utilities statewide. Visit our Illinois state page for a full comparison of water systems.