Big Horn County Lake Quality
Montana, 4 lakes, measured by Montana DEQ
Big Horn County has 4 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. 1 of those lake carry recent nutrient and algae readings. The county-level summary describes that subset, not every water body listed. The county's readings sit in the middle of the Montana range, with one or two lakes pulling the average up or down depending on year.
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. Bighorn Lake has the lowest nutrient and algae readings in the county.
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Quick Answers for Big Horn County
Planning a trip? Check special fishing regulations for Bighorn Lake — or check the official Montana fishing regulations.
All Lakes in Big Horn County
4 lakes · 1 ranked on readings, 3 without enough sampling1 lake ranked on readings · 3 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Max Depth | Access |
|---|---|---|---|---|---|---|---|
| 1 | Bighorn LakeBig Horn | No recent samples | 37 µg/L | 17.1 µg/L | No recent samples | No recent samples | Not recorded |
| Arapooish PondBig Horn | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | ✓ Public | |
| Lodge Grass Storage ReservoirBig Horn | No recent samples | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Tongue River ReservoirBig Horn | No recent samples | No recent samples | No recent samples | No recent samples | 54 ft | ✓ Public |
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.