WaterQ

City Water Quality Rankings in Illinois

635 cities ranked by drinking water quality.

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Popular city water quality comparisons

Alto Pass, IL vs Aurora, IL Compare → Beach Park, IL vs Cahokia Heights, IL Compare → Chatham, IL vs Davis Junction, IL Compare → Evanston, IL vs Forrest, IL Compare →

Trending Cities

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#601
Mt Carmel
County, IL
22 F
#602
Lawrenceville
County, IL
21 F
#603
Wilmington
County, IL
20 F
#604
New Berlin
County, IL
19 F
#605
Toulon
County, IL
17 F
#606
Markham
County, IL
14 F
#607
Crest Hill
County, IL
11 F
#608
Coal City
County, IL
6 F
#609
Galva
County, IL
5 F
#610
Gardner
County, IL
4 F
#611
Anna
County, IL
0 F
#612
Assumption
County, IL
0 F
#613
Buncombe
County, IL
0 F
#614
Chenoa
County, IL
0 F
#615
Durand
County, IL
0 F
#616
Edinburg
County, IL
0 F
#617
Gillespie
County, IL
0 F
#618
Joliet
County, IL
0 F
#619
Lakewood
County, IL
0 F
#620
Leroy
County, IL
0 F
#621
Litchfield
County, IL
0 F
#622
Maple Park
County, IL
0 F
#623
Menard
County, IL
0 F
#624
Milan
County, IL
0 F

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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