Cleanest Lakes in Lewis and Clark County, Montana
Lake Helena Outlet in Lewis and Clark County leads the rankings with a water quality grade of D. Below are the top 13 cleanest monitored lakes in Lewis and Clark County, Montana, ranked by EPA water quality score.
Ranked List
| # | Lake | County | Grade | Clarity | Phosphorus | Algae |
|---|---|---|---|---|---|---|
| 1 | Lake Helena Outlet | Lewis and Clark | D | - | 115.5 µg/L | - |
| 2 | Helena Valley Regulating Reservoir | Lewis and Clark | NR | - | - | - |
| 3 | Heart Lake | Lewis and Clark | NR | - | - | - |
| 4 | Gravelly Range Lake | Lewis and Clark | NR | - | - | - |
| 5 | Chessman Reservoir | Lewis and Clark | NR | - | - | - |
| 6 | Scott Reservoir | Lewis and Clark | NR | - | - | - |
| 7 | Connors Lake | Lewis and Clark | NR | - | - | - |
| 8 | Smith Lake | Lewis and Clark | NR | - | - | - |
| 9 | Nilan Reservoir | Lewis and Clark | NR | - | - | - |
| 10 | Anderson Lake | Lewis and Clark | NR | - | - | - |
| 11 | Krone Lake | Lewis and Clark | NR | - | - | - |
| 12 | Meyer Lake | Lewis and Clark | NR | - | - | - |
| 13 | Bean Lake | Lewis and Clark | NR | - | - | - |
More Answers for Lewis and Clark County, Montana
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