Bayfield County Lake Quality
Wisconsin, 55 lakes, average grade A (Excellent)
Bayfield County has 55 graded lakes, enough that within-county variation matters as much as the county average. Some are deep glacial basins, others are shallow agricultural-watershed waters, and the grade distribution reflects that mix. On average, Bayfield County lakes grade an A. That puts it near the top of the Wisconsin county ranking.
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 Long Lake (A); the most-stressed is Duck Lake (D).
Quick Answers for Bayfield County
Planning a trip? Check special fishing regulations for Long Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
DNR Reports (20)
Wisconsin DNR Fisheries Survey resources for lakes in Bayfield County. Showing 12 most recent — browse all reports →
- 2025Eau Claire, Middle spring shocking survey, 2025Spring Shocking Survey · WI DNR · 2025 (PDF)
- 2025Eau Claire, Upper spring shocking survey, 2025Spring Shocking Survey · WI DNR · 2025 (PDF)
- 2025Lake Namekagon fishery management plan, 2025Management Plan · WI DNR · 2025 (PDF)
- 2025Lake Owen spring shocking survey, 2025Spring Shocking Survey · WI DNR · 2025 (PDF)
- 2025Survival and return on investment of stocked walleye in Bayfield and Douglas counties, 2025Walleye Survey · WI DNR · 2025 (PDF)
- 2024Cable Wiley lakes spring shocking survey, 2024Spring Shocking Survey · WI DNR · 2024 (PDF)
- 2024Diamond Lake comprehensive survey, 2024Comprehensive Survey · WI DNR · 2024 (PDF)
- 2024Long Lake spring shocking survey, 2024Spring Shocking Survey · WI DNR · 2024 (PDF)
- 2024Pickerel Lake spring shocking survey, 2024Spring Shocking Survey · WI DNR · 2024 (PDF)
- 2024Siskiwit Lake spring shocking survey, 2024Spring Shocking Survey · WI DNR · 2024 (PDF)
- 2023Delta Lake spring shocking survey, 2023Spring Shocking Survey · WI DNR · 2023 (PDF)
- 2023Island Lake spring shocking survey, 2023Spring Shocking Survey · WI DNR · 2023 (PDF)
All Lakes in Bayfield County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Long Lake | A | 52.5 ft | 28 ft | 13.7 µg/L |
| 2 | Upper Eau Claire Lake | A | 61.5 ft | 92 ft | 11.5 µg/L |
| 3 | Spider Lake | A | 18 ft | 15 ft | - |
| 4 | Bass Lake | A | 18.9 ft | 43 ft | - |
| 5 | Hammil Lake | A | 48.4 ft | 47 ft | 12.2 µg/L |
| 6 | Anderson Lake | A | 30.3 ft | 46 ft | 5 µg/L |
| 7 | Tahkodah Lake | A | 32.8 ft | - | 13.7 µg/L |
| 8 | Island Lake | A | 55.8 ft | 51 ft | - |
| 9 | Middle Eau Claire Lake | A | 60.7 ft | 66 ft | 12.8 µg/L |
| 10 | Flynn Lake | A | 29.5 ft | - | - |
| 11 | Robinson Lake | A | 43.5 ft | 36 ft | 15.1 µg/L |
| 12 | Turtle Lake | A | 15.6 ft | - | - |
| 13 | Diamond Lake | A | 42.7 ft | 83 ft | 11.1 µg/L |
| 14 | Breakfast Lake | A | 41 ft | - | - |
| 15 | Cranberry Lake | A | 30.3 ft | - | 18.9 µg/L |
| 16 | Lower Eau Claire Lake | A | 47.6 ft | 41 ft | 13 µg/L |
| 17 | Samoset Lake | A | 44.3 ft | 40 ft | 13.3 µg/L |
| 18 | Kelly Lake | A | 49.2 ft | - | - |
| 19 | Lake Delta | A | 46.8 ft | 30 ft | - |
| 20 | Lake Owen | A | 78.7 ft | 95 ft | 12.4 µg/L |
| 21 | Crystal Lake | A | 53.3 ft | 29 ft | - |
| 22 | Eagle Lake | A | 59.1 ft | 52 ft | 14.3 µg/L |
| 23 | George Lake | A | 45.9 ft | 50 ft | - |
| 24 | Pigeon Lake | A | 42.7 ft | 26 ft | 13.3 µg/L |
| 25 | Lake Wilipyro | A | 34.5 ft | 25 ft | 13.9 µg/L |
| 26 | Half Moon Lake | A | 26.2 ft | - | 17.2 µg/L |
| 27 | Cable Lake | A | 50.9 ft | - | 14.1 µg/L |
| 28 | Twin Lake North | A | 32.8 ft | 25 ft | - |
| 29 | Millicent Lake | A | 75.5 ft | - | - |
| 30 | Hart Lake | A | 70.5 ft | 54 ft | - |
| 31 | Buskey Bay Lake | A | 70.9 ft | 51 ft | - |
| 32 | Lower Eau Claire Lake | A | 20 ft | 41 ft | - |
| 33 | Bufo Lake | A | 32.8 ft | 35 ft | 14 µg/L |
| 34 | Reynard Lake | A | 33.6 ft | 55 ft | 5 µg/L |
| 35 | Taylor Lake-Deep Hole | A | 19.7 ft | 15 ft | 19.8 µg/L |
| 36 | Inch Lake | A | 46.1 ft | 40 ft | - |
| 37 | Twin Bear Lake | A | 64 ft | 59 ft | - |
| 38 | Sand Bar Lake | A | 62.3 ft | 49 ft | 9.9 µg/L |
| 39 | Tomahawk Lake | A | 45.9 ft | 42 ft | 10.8 µg/L |
| 40 | Bony Lake | A | 64.8 ft | 55 ft | 13.9 µg/L |
| 41 | Bladder Lake | A | 59.1 ft | 35 ft | - |
| 42 | Lk Superior Siskiwit Bay 0.15 Mi Siskiwit R Mouth Lake | A | - | - | 6 µg/L |
| 43 | Namekagon Lake | A | - | 23 ft | 11.7 µg/L |
| 44 | Duplicate Lake | A | - | - | 10 µg/L |
| 45 | Nc Cheq Bay Lake | A | - | - | 5.9 µg/L |
| 46 | Clay Lake | A | 11.5 ft | 45 ft | 18 µg/L |
| 47 | Wishbone Lake | A | 15.6 ft | 40 ft | 24 µg/L |
| 48 | Lester Lake | A | 13.1 ft | 50 ft | 10.4 µg/L |
| 49 | Siskiwit Lake | B | - | 13 ft | 24 µg/L |
| 50 | Siskiwit Lake | B | - | 13 ft | 23.3 µg/L |
| 51 | East Wetland Inlet To Lake Ree | B | - | - | 28.2 µg/L |
| 52 | Wiley Lake | B | - | - | 27 µg/L |
| 53 | Stratton Ponds | B | 9.8 ft | 6 ft | 20.9 µg/L |
| 54 | Bear Lake | C | 6.6 ft | - | 48.6 µg/L |
| 55 | Duck Lake | D | 5.1 ft | 30 ft | - |
Source: EPA National Aquatic Resource Surveys, 2026.