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

Valley County Lake Quality

Montana, 21 lakes, measured by Montana DEQ

The county-level average smooths over real differences — a single agricultural watershed near the southwest corner can pull the average down even if the rest of the county runs clean. The 21 monitored lakes in Valley 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 Valley County

Top-rated places to stay near Valley County

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Quick Answers for Valley County

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

Planning a trip? Check special fishing regulations for Corral Junction Number Two Detention Reservoir — or check the official Montana fishing regulations.

All Lakes in Valley County

21 lakes · 0 ranked on readings, 21 without enough sampling0 lakes ranked on readings · 21 without enough sampling, hidden

#LakeClarityPhosphorusAlgaeTrophicAccess
Corral Junction Number Two Detention ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Forrest ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Collins ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Gutshot Detention ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Grub Detention ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
South Beaver ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Itcaina ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Arrambide ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Jim ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Triple Crossing ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Baalke SloughValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lake GrableValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Cornwell ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Mahan and Hoyt ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Todd LakesValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Frazer LakeValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Cactus Flat Detention ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Willow Creek Flat ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Willow Flat ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Target Detention ReservoirValleyNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lori Detention ReservoirValleyNo 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.