City Water Quality Rankings in Illinois
631 cities ranked by drinking water quality.
Popular city water quality comparisons
Trending Cities
#145
Astoria
County, IL
85 B
#146 Braidwood
County, IL
85 B
#147 Champaign
County, IL
85 B
#148 Darien
County, IL
85 B
#149 Elk Grove Village
County, IL
85 B
#150 Hampton
County, IL
85 B
#151 Lisle
County, IL
85 B
#152 Loves Park
County, IL
85 B
#153 Martinsville
County, IL
85 B
#154 Morrison
County, IL
85 B
#155 Niles
County, IL
85 B
#156 Riverdale
County, IL
85 B
#157 Round Lake
County, IL
85 B
#158 South Holland
County, IL
85 B
#159 Aurora
County, IL
84 B
#160 Beecher
County, IL
84 B
#161 Chicago Ridge
County, IL
84 B
#162 Downers Grove
County, IL
84 B
#163 Dunlap
County, IL
84 B
#164 East Carondelet
County, IL
84 B
#165 Fairbury
County, IL
84 B
#166 Godfrey
County, IL
84 B
#167 Hinsdale
County, IL
84 B
#168 Machesney Park
County, IL
84 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.