City Water Quality Rankings in Illinois
635 cities ranked by drinking water quality.
Popular city water quality comparisons
Trending Cities
#145
Camp Point
County, IL
87 B
#146 Elk Grove Village
County, IL
87 B
#147 Homewood
County, IL
87 B
#148 Round Lake
County, IL
87 B
#149 Thomasboro
County, IL
87 B
#150 Astoria
County, IL
86 B
#151 Ava
County, IL
86 B
#152 Channahon
County, IL
86 B
#153 Freeburg
County, IL
86 B
#154 Grayslake
County, IL
86 B
#155 Hanna City
County, IL
86 B
#156 Hinckley
County, IL
86 B
#157 Homer
County, IL
86 B
#158 Lagrange Park
County, IL
86 B
#159 Littleton
County, IL
86 B
#160 Percy
County, IL
86 B
#161 Shelbyville
County, IL
86 B
#162 Cary
County, IL
85 B
#163 Champaign
County, IL
85 B
#164 Dowell
County, IL
85 B
#165 Godfrey
County, IL
85 B
#166 Hampton
County, IL
85 B
#167 Hopkins Park
County, IL
85 B
#168 Lebanon
County, IL
85 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.