WaterQ

City Water Quality Rankings in Illinois

635 cities ranked by drinking water quality.

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Popular city water quality comparisons

Alto Pass, IL vs Aurora, IL Compare → Beach Park, IL vs Cahokia Heights, IL Compare → Chatham, IL vs Davis Junction, IL Compare → Evanston, IL vs Forrest, IL Compare →

Trending Cities

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#25
Thomson
County, IL
100 A
#26
Toluca
County, IL
100 A
#27
Tremont
County, IL
100 A
#28
Cerro Gordo
County, IL
99 A
#29
Dupo
County, IL
98 A
#30
East Moline
County, IL
98 A
#31
Minier
County, IL
98 A
#32
Naperville
County, IL
98 A
#33
Pekin
County, IL
98 A
#34
Virden
County, IL
98 A
#35
Bethany
County, IL
97 A
#36
Hanover Park
County, IL
97 A
#37
Lagrange
County, IL
97 A
#38
Sublette
County, IL
97 A
#39
Bunker Hill
County, IL
96 A
#40
Clarendon Hills
County, IL
96 A
#41
Forsyth
County, IL
96 A
#42
Mackinaw
County, IL
96 A
#43
Macon
County, IL
96 A
#44
Mossville
County, IL
96 A
#45
Odell
County, IL
96 A
#46
Rochester
County, IL
96 A
#47
Rockford
County, IL
96 A
#48
Roxana
County, IL
96 A

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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