WaterQ

City Water Quality Rankings in Illinois

635 cities ranked by drinking water quality.

Popular city water quality comparisons

Trending Cities

#385
Wauconda
County, IL
69 C
#386
Cicero
County, IL
68 C
#387
Elmwood
County, IL
68 C
#388
Fulton
County, IL
68 C
#389
Long Grove
County, IL
68 C
#390
Morton Grove
County, IL
68 C
#391
Oak Brook
County, IL
68 C
#392
Romeoville
County, IL
68 C
#393
Taylorville
County, IL
68 C
#394
Arcola
County, IL
67 C
#395
Bellwood
County, IL
67 C
#396
Kingston
County, IL
67 C
#397
Lake Bluff
County, IL
67 C
#398
Malta
County, IL
67 C
#399
Pingree Grove
County, IL
67 C
#400
Sugar Grove
County, IL
67 C
#401
Ashland
County, IL
66 C
#402
Caseyville
County, IL
66 C
#403
Eureka
County, IL
66 C
#404
Glenwood
County, IL
66 C
#405
Herrin
County, IL
66 C
#406
Highwood
County, IL
66 C
#407
Jonesboro
County, IL
66 C
#408
Knoxville
County, IL
66 C

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.

Explore More Water Quality Data