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Illinois Water Quality
Illinois ranks #23 out of 49 states for tap water quality with a score of 85.4 out of 100.
Based on 582 scored cities covering 34.8% of the state's served population.
Summary
Cities Needing Improvement
Cities listed carry the most serious water quality verdicts in Illinois, worst first, then the lowest scores. A city rated Safe is never listed.
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Frequently Asked Questions About Illinois Water Quality
Illinois ranks #23 out of 49 states and territories for water quality with a score of 85.4 out of 100 and a grade of A. A total of 582 cities were tested across the state.
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