Safest Lakes to Swim In in Illinois
1 lakes in Illinois qualify as safest for swimming, all hold grade A or B and report chlorophyll-a (algae) under 10 µg/L. Always check local advisories on the day you swim.
Ranked List
| # | Lake | County | Grade | Clarity | Phosphorus | Algae |
|---|---|---|---|---|---|---|
| 1 | Lake Calumet | Cook | A | 4.1 ft | 16.5 µg/L | 5.4 µg/L |
More Answers for Illinois
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