WaterQ

City Water Quality Rankings in Illinois

635 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#97
Waverly
County, IL
92 A
#98
Williamsville
County, IL
92 A
#99
Winnebago
County, IL
92 A
#100
Flanagan
County, IL
91 A
#101
Lakemoor
County, IL
91 A
#102
Morrison
County, IL
91 A
#103
Park City
County, IL
91 A
#104
Alsip
County, IL
90 A
#105
Atlanta
County, IL
90 A
#106
Belle Rive
County, IL
90 A
#107
Blue Island
County, IL
90 A
#108
Carterville
County, IL
90 A
#109
Elmhurst
County, IL
90 A
#110
Gibson City
County, IL
90 A
#111
Great Lakes
County, IL
90 A
#112
Greenup
County, IL
90 A
#113
Hartford
County, IL
90 A
#114
Lanark
County, IL
90 A
#115
Momence
County, IL
90 A
#116
Mt Vernon
County, IL
90 A
#117
Mt. Sterling
County, IL
90 A
#118
Paxton
County, IL
90 A
#119
Petersburg
County, IL
90 A
#120
Pleasant Plains
County, IL
90 A

Frequently Asked Questions

How are city water quality rankings calculated in Illinois?

WaterQ city rankings are based on EPA SDWIS data across local public water systems, including contaminant detections, compliance violations, and recency-weighted score signals.

Can I compare two cities in Illinois?

Yes. Use the city comparison links on this page or open the Compare tool to evaluate two cities side by side on score, grade, and water system coverage.

How often does WaterQ refresh city data?

City-level metrics refresh when new EPA data is processed. Check city pages for latest score and violation context.

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