C40/100
ROCK ISLAND — Water Quality Report 2026
Serving 39,018 people · Illinois
Water Source
Surface Water
County
—
System ID
IL1610650
Violations
45
Contaminant Test Results
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.006 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
3
Violations (last 5yr)
1
Unresolved
0
Health-Related
TIER 3Unresolved
Surface water treatment technique failure
TIER 3Resolved
Failed to issue ongoing public notification
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: October 1, 2023 – March 7, 2024Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: April 1, 2023 – June 30, 2023Enforcement: 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 ROCK ISLAND
Is ROCK ISLAND water safe to drink?
ROCK ISLAND water receives a grade of C (40/100), which is considered fair. 0 contaminant(s) exceed EPA legal limits and 45 violation(s) are on record. Customers may want to consider using a water filter.
What contaminants has ROCK ISLAND detected?
69 contaminants were tested in ROCK ISLAND's water. Notable contaminants include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 exceed EPA health goals (MCLGs).
Does ROCK ISLAND have any EPA violations?
Yes, ROCK ISLAND has 45 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 ROCK ISLAND serve?
ROCK ISLAND serves approximately 39,018 people, Illinois. The system provides water to 1 community: Rock Island.
What type of water does ROCK ISLAND provide?
ROCK ISLAND sources its water from surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is IL1610650.
How does ROCK ISLAND compare to other utilities in Illinois?
ROCK ISLAND scores 40/100 with a grade of C (fair). This score indicates room for improvement compared to other utilities. Visit our Illinois state page for a full comparison of water systems.