Brown County Lake Quality
Minnesota, 7 lakes, average grade F (Very Poor)
Brown County has 7 graded 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 county average is F — the most-stressed bracket in our rubric. Most monitored lakes here show persistent nutrient loading and algal pressure.
The county's lakes lean shallow, which makes the grades sensitive to wind, sediment-resuspension, and any nutrient inputs from the watershed. The cleanest lake on the books is Wellner-Hageman Reservoir (D); the most-stressed is Unnamed Lake (F).
Quick Answers for Brown County
Planning a trip? Check special fishing regulations for Wellner-Hageman Reservoir, whether the fish are safe to eat, and the best times to fish — or browse the full Minnesota regulations index.
DNR Reports (12)
Minnesota DNR LakeFinder resources for lakes in Brown County. browse all reports →
- —Fisheries Lake Survey — Wellner-Hageman ReservoirFisheries Lake Survey · MN DNR LakeFinder
- —Fisheries Lake Survey — Sleepy EyeFisheries Lake Survey · MN DNR LakeFinder
- —Fisheries Lake Survey — HanskaFisheries Lake Survey · MN DNR LakeFinder
- —Fisheries Lake Survey — ClearFisheries Lake Survey · MN DNR LakeFinder
- —Fish Stocking History — ClearFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — ClearPublic Water Access Sites · MN DNR LakeFinder
- —Fish Stocking History — HanskaFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — HanskaPublic Water Access Sites · MN DNR LakeFinder
- —Fish Stocking History — Sleepy EyeFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — Sleepy EyePublic Water Access Sites · MN DNR LakeFinder
- —Fish Stocking History — Wellner-Hageman ReservoirFish Stocking History · MN DNR LakeFinder
- —Public Water Access Sites — Wellner-Hageman ReservoirPublic Water Access Sites · MN DNR LakeFinder
All Lakes in Brown County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Wellner-Hageman Reservoir | D | 3.7 ft | 24 ft | 45 µg/L |
| 2 | Sleepy Eye Lake | D | 3.3 ft | 21 ft | 39.5 µg/L |
| 3 | Unnamed Lake | F | 0.3 ft | - | 1300 µg/L |
| 4 | Clear Lake | F | 0.8 ft | 8 ft | 196 µg/L |
| 5 | Hanska Lake | F | 1 ft | 16 ft | 219 µg/L |
| 6 | Domeier Lake | F | 1 ft | - | 246 µg/L |
| 7 | Omsrud Lake | F | 1 ft | - | 199 µg/L |
Source: EPA National Aquatic Resource Surveys, 2026.