Illinois
Water Quality Report
69 Fair
Average Score
69/100
Water Systems
874
Population
11.9M
Violations
1 all resolved
Score Distribution
3 A
3 B
0 C
0 D
0 F
Top Contaminant Violations
| Contaminant | Violations |
|---|---|
| Manganese | 1 |
| Uranium | 1 |
| Chromium (Total) | 1 |
| Fluoride | 1 |
Lowest Scoring Water Systems
73
Suburban Cook County Water B
IL0310002 Chicago, IL 1,500,000 served
85
City Water Light and Power Springfield B
IL1670100 Springfield, IL 114,230 served
89
Chicago Department of Water Management B
IL0310001 Chicago, IL 2,700,000 served
93
Rockford Water Division A
IL2010600 Rockford, IL 148,655 served
97
City of Aurora Water A
IL0890230 Aurora, IL 180,542 served
Counties in Illinois
Cities in Illinois
View all 635 cities →Popular City Comparisons in Illinois
Quickly compare major cities in Illinois by water quality score and grade.
Frequently Asked Questions
Is tap water in Illinois safe to drink?
Illinois has an average WaterQ score of 69/100 across 874 public water systems. Safety can vary by city and system, so check your local report for recent violations and contaminants.
How many water systems are in Illinois?
WaterQ currently tracks 874 public water systems in Illinois.
Where can I compare cities in Illinois?
Use the city list below to open detailed reports, or visit the compare tool to benchmark two cities side-by-side on score, grade, and system coverage.