WaterQ

City Water Quality Rankings in Illinois

631 cities ranked by drinking water quality.

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Popular city water quality comparisons

Alto Pass, IL vs Beach Park, IL Compare → Cahokia Heights, IL vs Chatham, IL Compare → Davis Junction, IL vs Evanston, IL Compare → Freeport, IL vs Groveland, IL Compare →

Trending Cities

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#529
Oswego
County, IL
42 F
#530
Pana
County, IL
42 F
#531
South Elgin
County, IL
42 F
#532
Dwight
County, IL
41 F
#533
Lockport
County, IL
41 F
#534
Pontiac
County, IL
41 F
#535
Brookfield
County, IL
40 F
#536
Goreville
County, IL
40 F
#537
Mounds
County, IL
40 F
#538
Ottawa
County, IL
40 F
#539
Utica
County, IL
40 F
#540
Algonquin
County, IL
39 F
#541
Chicago
County, IL
39 F
#542
St. Jacob
County, IL
39 F
#543
Barrington
County, IL
38 F
#544
Chillicothe
County, IL
38 F
#545
Montgomery
County, IL
38 F
#546
Erie
County, IL
37 F
#547
Jerseyville
County, IL
37 F
#548
Tuscola
County, IL
37 F
#549
White Hall
County, IL
37 F
#550
Altamont
County, IL
35 F
#551
Burbank
County, IL
35 F
#552
Highwood
County, IL
35 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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