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

Chouteau County Lake Quality

Montana, 20 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. 1 of those lake carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. The monitored lakes here are mostly shallow, productive basins where summer algae is common; each lake page shows its own readings beside the EPA condition class.

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. Boneau Reservoir has the lowest nutrient and algae readings in the county.

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Where to stay near Chouteau County

Top-rated places to stay near Chouteau County

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All Lakes in Chouteau County

20 lakes · 1 ranked on readings, 19 without enough sampling1 lake ranked on readings · 19 without enough sampling, hidden

#LakeClarityPhosphorusAlgaeTrophicAccess
1Boneau ReservoirChouteauNo recent samples50 µg/L39 µg/LNo recent samplesNot recorded
Williamson ReservoirChouteauNo recent samples410 µg/L6.7 µg/LNo recent samplesNot recorded
Flick LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Rice ReservoirChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Floweree LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Antelope LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Clear LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Harwood LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Shonkin LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Big LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
White LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Big LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lost LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Kingsbury LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Sand LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Big Sag LakeChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Panton Coulee ReservoirChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Dammel ReservoirChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Seifort ReservoirChouteauNo recent samplesNo recent samplesNo recent samplesNo recent samplesNot recorded
Lonesome LakeChouteauNo 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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Source: the Montana Department of Environmental Quality. See data sources.