WaterQ

City Water Quality Rankings in Illinois

635 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#193
Spring Valley
County, IL
84 B
#194
Stillman Valley
County, IL
84 B
#195
Thompsonville
County, IL
84 B
#196
Villa Park
County, IL
84 B
#197
Westmont
County, IL
84 B
#198
Wheeling
County, IL
84 B
#199
Wood River
County, IL
84 B
#200
Catlin
County, IL
83 B
#201
Flora
County, IL
83 B
#202
Flossmoor
County, IL
83 B
#203
Hebron
County, IL
83 B
#204
Ingleside
County, IL
83 B
#205
Kankakee
County, IL
83 B
#206
Palos Park
County, IL
83 B
#207
Sandwich
County, IL
83 B
#208
South Holland
County, IL
83 B
#209
Stickney
County, IL
83 B
#210
Braidwood
County, IL
82 B
#211
Byron
County, IL
82 B
#212
Chatsworth
County, IL
82 B
#213
Depue
County, IL
82 B
#214
Hamel
County, IL
82 B
#215
Lemont
County, IL
82 B
#216
Lewistown
County, IL
82 B

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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