Illinois Water Quality
Illinois ranks #49 out of 51 states for tap water quality with a score of 78.7 out of 100.
Based on 753 scored cities covering 99.1% of the state's served population.
Summary
Best Cities in Illinois
Cities Needing Improvement
Cities listed have the lowest water quality scores in Illinois.
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Frequently Asked Questions About Illinois Water Quality
Illinois ranks #49 out of 51 states and territories for water quality with a score of 78.7 out of 100 and a grade of B. A total of 753 cities were tested across the state.
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