Cleanest Lakes in Flathead County, Montana
Tally Lake in Flathead County leads the rankings with a water quality grade of A and 15.2 ft of clarity. Below are the top 44 cleanest monitored lakes in Flathead County, Montana, ranked by EPA water quality score.
Ranked List
| # | Lake | County | Grade | Clarity | Phosphorus | Algae |
|---|---|---|---|---|---|---|
| 1 | Tally Lake | Flathead | A | 15.2 ft | 4.5 µg/L | 0.9 µg/L |
| 2 | Nla Lake | Flathead | A | 47.6 ft | 1.1 µg/L | 0.6 µg/L |
| 3 | Nla Lake | Flathead | A | 20 ft | 13.8 µg/L | 1.1 µg/L |
| 4 | Whitefish Lake | Flathead | A | 22 ft | 3 µg/L | 1.1 µg/L |
| 5 | Whitefish Lake | Flathead | A | 23.5 ft | 3.3 µg/L | 1.6 µg/L |
| 6 | Hanson-Doyle Lake | Flathead | A | - | 7.3 µg/L | 2.3 µg/L |
| 7 | Lost Coon Lake | Flathead | A | - | 9.7 µg/L | 2.5 µg/L |
| 8 | Foys Lake | Flathead | A | - | 15.8 µg/L | 4.1 µg/L |
| 9 | Rogers Lake | Flathead | A | - | 11.6 µg/L | 2.6 µg/L |
| 10 | Beaver Lake | Flathead | A | - | 18.5 µg/L | 3.5 µg/L |
| 11 | Smith Lake | Flathead | A | - | 7.4 µg/L | 1.4 µg/L |
| 12 | Dollar Lake | Flathead | A | - | 7.2 µg/L | 2.9 µg/L |
| 13 | Lake Blaine | Flathead | A | - | 10 µg/L | 2.4 µg/L |
| 14 | Bailey Lake | Flathead | A | - | 7.1 µg/L | 2.2 µg/L |
| 15 | Flathead Lake | Flathead | A | - | 2.4 µg/L | 0.6 µg/L |
| 16 | Lake Five | Flathead | A | - | 10.6 µg/L | 3.7 µg/L |
| 17 | Spencer Lake | Flathead | A | - | 8.8 µg/L | 2.6 µg/L |
| 18 | Ashley Lake | Flathead | A | - | 9.8 µg/L | 2.1 µg/L |
| 19 | Peterson Lake | Flathead | A | - | 7.6 µg/L | 1.5 µg/L |
| 20 | Blanchard Lake | Flathead | A | - | 5.5 µg/L | 1.4 µg/L |
| 21 | Abbot Lake | Flathead | A | - | 9 µg/L | 2 µg/L |
| 22 | Murray Lake | Flathead | A | - | 13.4 µg/L | 4.2 µg/L |
| 23 | Halfmoon Lake | Flathead | A | - | 5.9 µg/L | 1.7 µg/L |
| 24 | Echo Lake | Flathead | A | - | 13.9 µg/L | 3.2 µg/L |
| 25 | Bootjack Lake | Flathead | A | - | 15.4 µg/L | 3.5 µg/L |
| 26 | Skyles Lake | Flathead | A | - | 6 µg/L | 2.3 µg/L |
| 27 | Flathead Lake | Flathead | A | - | 3 µg/L | 0.8 µg/L |
| 28 | Ashley Lake | Flathead | A | - | 9.5 µg/L | 2.2 µg/L |
| 29 | Little Bitterroot Lake | Flathead | A | - | 3.9 µg/L | 1.2 µg/L |
| 30 | Upper Whitefish Lake | Flathead | A | - | 4.1 µg/L | 0.7 µg/L |
| 31 | Lower Stillwater Lake | Flathead | A | - | 11 µg/L | 1.8 µg/L |
| 32 | Upper Stillwater Lake | Flathead | A | - | 5.7 µg/L | 1.5 µg/L |
| 33 | Mcgilvray Lake | Flathead | A | - | 6.9 µg/L | 1.8 µg/L |
| 34 | Lake Mcdonald | Flathead | A | - | 16 µg/L | 0.8 µg/L |
| 35 | Little Bitterroot Lake Center | Flathead | A | - | 4 µg/L | 1 µg/L |
| 36 | Lost Loon Lake | Flathead | A | - | 10.1 µg/L | 2.6 µg/L |
| 37 | Little Bitterroot Lake | Flathead | A | - | 2 µg/L | 0.9 µg/L |
| 38 | Little Bitterroot Lake | Flathead | A | - | 3 µg/L | 0.8 µg/L |
| 39 | Nla Lake | Flathead | A | 21.2 ft | 23.2 µg/L | 1.8 µg/L |
| 40 | Lake Mcdonald | Flathead | A | - | 20.5 µg/L | 0.7 µg/L |
| 41 | Lake Mcdonald | Flathead | B | - | 39.5 µg/L | 0.7 µg/L |
| 42 | Lake Mcdonald | Flathead | B | - | 36.5 µg/L | 0.7 µg/L |
| 43 | Nla Lake | Flathead | B | 19.3 ft | 9500 µg/L | 1.5 µg/L |
| 44 | Nla Lake | Flathead | C | - | 12000 µg/L | 0.9 µg/L |