Safest Lakes to Swim In in Montana
7 lakes in Montana 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 | Tally Lake | Flathead | A | 15.2 ft | 4.7 µg/L | 0.8 µg/L |
| 2 | Whitefish Lake | Flathead | A | 22 ft | 2.8 µg/L | 0.9 µg/L |
| 3 | Swan Lake North End | Lake | A | - | 3.1 µg/L | 1.1 µg/L |
| 4 | Little Bitterroot Lake Center | Flathead | A | - | 4 µg/L | 1 µg/L |
| 5 | Inez Lake | Missoula | A | - | 7.1 µg/L | 1.8 µg/L |
| 6 | Alva Lake | Missoula | A | - | 4.7 µg/L | 0.7 µg/L |
| 7 | Cooney Reservoir | Carbon | B | 12.5 ft | 20 µg/L | 2.6 µg/L |
More Answers for Montana
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