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LakeQuality
Late afternoon sun over Slim Lake, scattering a bright path across wind-textured water

Sanders County Lake Quality

Montana, 10 lakes, measured by Montana DEQ

Sanders County has 10 monitored lakes — a thin enough sample that one or two stressed lakes can move the county average noticeably. Use the per-lake pages below for what actually matters. The 10 monitored lakes in Sanders County carry whatever clarity, phosphorus, and chlorophyll-a readings Montana DEQ has published, shown as reported.

Most of the county's monitored lakes are shallow, under 50 feet, which means wind keeps the water column mixed all summer and sediment-bound phosphorus releases back into the surface layer whenever the bottom is disturbed.

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Where to stay near Sanders County

Top-rated places to stay near Sanders County

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Quick Answers for Sanders County

Cleanest lakes in Sanders County →Cleanest lakes in Montana →Best swimming lakes in Montana →

Planning a trip? Check special fishing regulations for Cabinet Gorge Reservoir — or check the official Montana fishing regulations.

All Lakes in Sanders County

10 lakes · 0 ranked on readings, 10 without enough sampling0 lakes ranked on readings · 10 without enough sampling, hidden

#LakeClarityPhosphorusAlgaeTrophicMax DepthAccess
Cabinet Gorge ReservoirSandersNo recent samplesNo recent samplesNo recent samplesNo recent samples49 ftNot recorded
Wanless LakeSandersNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Noxon ReservoirSandersNo recent samplesNo recent samplesNo recent samplesNo recent samples156 ftNot recorded
Thompson Falls ReservoirSandersNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samples✓ Public
Rainbow LakeSandersNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lower Thompson LakeSandersNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Upper Dry Fork ReservoirSandersNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Dry Fork ReservoirSandersNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Fishtrap LakeSandersNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Rock LakeSandersNo recent samplesNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded

NR = no nutrient or algae reading on record. The measurements are published as the authority reports them. Where the data comes from.

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Other Counties in Montana

Missoula County

46 lakes

Carbon County

38 lakes

Yellowstone County

6 lakes

Flathead County

108 lakes

Big Horn County

4 lakes

Lake County

38 lakes

Browse every Montana lake, or the full directory of lakes across all United States (49 states), Canada (Ontario, Québec, Nova Scotia, British Columbia and Newfoundland and Labrador), and 38 other country hubs..

Source: the Montana Department of Environmental Quality. See data sources.