Yellowstone County Lake Quality
Montana, 6 lakes, measured by Montana DEQ
Yellowstone County has 6 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. Most monitored lakes in Yellowstone County carry favourable nutrient and algae readings for Montana.
The county's lakes lean shallow, which makes the readings sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest measured lake is Deep Mill Lake.
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Quick Answers for Yellowstone County
Planning a trip? Check special fishing regulations for Deep Mill Lake — or check the official Montana fishing regulations.
All Lakes in Yellowstone County
6 lakes · 1 ranked on readings, 5 without enough sampling1 lake ranked on readings · 5 without enough sampling, hidden
| # | Lake | Clarity | Phosphorus | Algae | Trophic | Access |
|---|---|---|---|---|---|---|
| 1 | Deep Mill LakeYellowstone | No recent samples | 20 µg/L | No recent samples | No recent samples | Not recorded |
| Broadview PondYellowstone | No recent samples | No recent samples | No recent samples | No recent samples | ✓ Public | |
| Alkali PondYellowstone | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Anita ReservoirYellowstone | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Lake ElmoYellowstone | No recent samples | No recent samples | No recent samples | No recent samples | Not recorded | |
| Rattlesnake ReservoirYellowstone | No recent samples | No recent samples | No recent samples | No recent samples | Not 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.