City Water Quality Rankings in Illinois
635 cities ranked by drinking water quality.
Popular city water quality comparisons
Trending Cities
#361
Worth
County, IL
72 C
#362 Alton
County, IL
71 C
#363 Carol Stream
County, IL
71 C
#364 Coal Valley
County, IL
71 C
#365 Franklin Park
County, IL
71 C
#366 Kenilworth
County, IL
71 C
#367 Lincolonwood
County, IL
71 C
#368 North Pekin
County, IL
71 C
#369 Orland Park
County, IL
71 C
#370 Bartlett
County, IL
70 C
#371 Cortland
County, IL
70 C
#372 Harrisburg
County, IL
70 C
#373 Itasca
County, IL
70 C
#374 Lake In The Hills
County, IL
70 C
#375 New Douglas
County, IL
70 C
#376 North Aurora
County, IL
70 C
#377 Palatine
County, IL
70 C
#378 Schaumburg
County, IL
70 C
#379 South Jacksonville
County, IL
70 C
#380 Worden
County, IL
70 C
#381 Belvidere
County, IL
69 C
#382 Moline
County, IL
69 C
#383 Oak Lawn
County, IL
69 C
#384 Rock Island
County, IL
69 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.