A88/100
OFALLON PWS — Water Quality Report 2026
Serving 32,515 people · Missouri
Water Source
Purchased Surface Water
County
—
System ID
MO6010588
Violations
2
Contaminant Test Results
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
chlorate | 1530.00 µg/L | — | Above Goal |
Lead (90th percentile) | 0.001 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
1
Violation (last 5yr)
0
Unresolved
0
Health-Related
TIER 3Resolved
Violation related to Consumer Confidence Report
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: June 1, 2025 – June 30, 2025Rule: Consumer Confidence 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 OFALLON PWS
Is OFALLON PWS water safe to drink?
OFALLON PWS water receives a grade of A (88/100), which is considered excellent. Out of 69 contaminants tested, none exceed EPA legal limits. 2 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has OFALLON PWS detected?
69 contaminants were tested in OFALLON PWS's water. Notable contaminants include Lead (90th percentile), chlorate. No contaminants exceed EPA legal limits. 2 exceed EPA health goals (MCLGs).
Does OFALLON PWS have any EPA violations?
Yes, OFALLON PWS has 2 EPA violation(s) on record, with the most recent in 2025. Violation types include MR, MCL. 1 are health-based violations.
How many people does OFALLON PWS serve?
OFALLON PWS serves approximately 32,515 people, Missouri. The system provides water to 1 community: O Fallon.
What type of water does OFALLON PWS provide?
OFALLON PWS sources its water from purchased surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is MO6010588.
How does OFALLON PWS compare to other utilities in Missouri?
OFALLON PWS scores 88/100 with a grade of A (excellent). This places it among the higher-performing utilities in the state. Visit our Missouri state page for a full comparison of water systems.