Polk County Lake Quality
Wisconsin, 73 lakes, average grade C (Fair)
Polk County in Wisconsin carries 73 graded lakes — one of the lake-richer counties in our dataset. Coverage that dense usually reflects active lake-association sampling alongside state-agency monitoring. Polk County averages to a C. The distribution behind that average matters more than the letter: a few stressed lakes versus many decent ones can produce the same average as the inverse.
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. Clear Lake (A) is the cleanest in the county.
Quick Answers for Polk County
Planning a trip? Check special fishing regulations for Clear Lake, whether the fish are safe to eat, and the best times to fish — or browse the full Wisconsin regulations index.
DNR Reports (8)
Wisconsin DNR Fisheries Survey resources for lakes in Polk County. browse all reports →
- 2025Deer Lake spring shocking survey, 2025Spring Shocking Survey · WI DNR · 2025 (PDF)
- 2024Apple River Flowage spring shocking survey, 2024Spring Shocking Survey · WI DNR · 2024 (PDF)
- 2024Bone Lake spring shocking survey, 2024Spring Shocking Survey · WI DNR · 2024 (PDF)
- 2022Big and Little Blake lakes spring shocking survey, 2022Spring Shocking Survey · WI DNR · 2022 (PDF)
- 2022Big Butternut Lake fisheries survey, 2022Fisheries Survey · WI DNR · 2022 (PDF)
- 2022Herby Lake spring shocking survey, 2022Spring Shocking Survey · WI DNR · 2022 (PDF)
- 2022Little Butternut Lake spring shocking survey, 2022Spring Shocking Survey · WI DNR · 2022 (PDF)
- —Bone Lake muskellunge survey, 2024-2025Musky Survey · WI DNR (PDF)
All Lakes in Polk County
| Rank | Lake | Grade | Clarity | Max Depth | Phosphorus |
|---|---|---|---|---|---|
| 1 | Clear Lake | A | 15.5 ft | 26 ft | 13.9 µg/L |
| 2 | Pike Lake | A | - | 33 ft | 13.4 µg/L |
| 3 | North Twin Lake | A | - | 27 ft | 10.1 µg/L |
| 4 | Deer Lake | A | 16 ft | 46 ft | 16.9 µg/L |
| 5 | Sand Lake | A | 20 ft | - | - |
| 6 | Half Moon Lake | A | 15.3 ft | 60 ft | 13.9 µg/L |
| 7 | South Twin Lake | A | - | - | 11.7 µg/L |
| 8 | Margaret Lake | A | 15.5 ft | 17 ft | 10.8 µg/L |
| 9 | Lower Pine Lake | A | 21 ft | 102 ft | 9.2 µg/L |
| 10 | Pipe Lake | A | 12 ft | 68 ft | 14.5 µg/L |
| 11 | Paulsen Lake | A | 12 ft | - | 12.7 µg/L |
| 12 | Church Pine Lake | A | 13 ft | 45 ft | 13.5 µg/L |
| 13 | Wind Lake | A | 10 ft | 7 ft | 17.2 µg/L |
| 14 | Pine Lake | A | 13 ft | 34 ft | 13.5 µg/L |
| 15 | Antler Lake | A | 13.4 ft | 22 ft | 15 µg/L |
| 16 | Round Lake | B | 11.5 ft | 26 ft | - |
| 17 | Swede Lake | B | 13 ft | 32 ft | - |
| 18 | Poplar Lake | B | 12.7 ft | - | - |
| 19 | Freedom Lakes | B | 9.5 ft | 4 ft | 19.9 µg/L |
| 20 | Lamont Lake | B | 12 ft | 28 ft | - |
| 21 | Moccasin Lake | B | 9.9 ft | 31 ft | - |
| 22 | Sandhill Lake | B | 8.2 ft | - | 19.2 µg/L |
| 23 | King Lake | B | 11.5 ft | 14 ft | 20.6 µg/L |
| 24 | Balsam Lake | B | 13 ft | 37 ft | 23.4 µg/L |
| 25 | Dace Lake | B | - | - | 21.3 µg/L |
| 26 | Balsam Lake | B | 6.6 ft | - | 15.2 µg/L |
| 27 | Bone Lake | B | 7.5 ft | 43 ft | 20.2 µg/L |
| 28 | Crescent Lake | B | 4.5 ft | 43 ft | 17.4 µg/L |
| 29 | Big Lake | B | 9 ft | 24 ft | 21.6 µg/L |
| 30 | Horseshoe Lake | B | 8.5 ft | - | 22.5 µg/L |
| 31 | Loveless Lake | B | 8.5 ft | 20 ft | 28.9 µg/L |
| 32 | Bear Trap Lake | B | 8.8 ft | 25 ft | 24.9 µg/L |
| 33 | Black Brook Flowage Lake | B | 10.5 ft | - | 46.6 µg/L |
| 34 | Clarey Lake | B | 4.3 ft | - | 18.8 µg/L |
| 35 | Mckenzie Lake | B | 7 ft | 25 ft | 26 µg/L |
| 36 | Ember Lake | B | 8.2 ft | - | 20.2 µg/L |
| 37 | Rice Lake | C | 4.5 ft | 10 ft | 25.4 µg/L |
| 38 | Long Lake | C | 5.9 ft | 17 ft | 26.1 µg/L |
| 39 | Long Lake | C | 5 ft | 44 ft | 27.7 µg/L |
| 40 | Mud Lake | C | 4.3 ft | 15 ft | 24.7 µg/L |
| 41 | Ward Lake | C | 6 ft | 43 ft | 22.4 µg/L |
| 42 | Diamond Lake | C | 8.2 ft | - | - |
| 43 | Lost Lake | C | 6 ft | - | 25.4 µg/L |
| 44 | North Pipe Lake | C | 5.8 ft | 37 ft | 29.3 µg/L |
| 45 | Unnamed Lake | C | 5 ft | - | 22.4 µg/L |
| 46 | Dinger Lake | C | 6.2 ft | - | 22 µg/L |
| 47 | Big Round Lake | C | 4.9 ft | 17 ft | 27.6 µg/L |
| 48 | Cedar Lake | C | 6.1 ft | 32 ft | 42.3 µg/L |
| 49 | North White Ash Lake | C | 5 ft | 9 ft | 59.1 µg/L |
| 50 | Wapogasset Lake | C | 6 ft | 32 ft | 30.6 µg/L |
| 51 | Camelia Lake | C | 6 ft | - | 32.6 µg/L |
| 52 | Little Blake Lake | C | 3.5 ft | 14 ft | 43.8 µg/L |
| 53 | Magnor Lake | C | 4 ft | 26 ft | 57.7 µg/L |
| 54 | Little Bass Lake | C | 5.5 ft | - | 37.8 µg/L |
| 55 | Pogo Lake | C | 5 ft | - | 38.2 µg/L |
| 56 | Balsam Lake Little Balsam Site | C | 5.7 ft | 37 ft | 42.7 µg/L |
| 57 | Little Butternut Lake | D | 3.7 ft | 23 ft | - |
| 58 | Big Butternut Lake | D | 4.5 ft | 19 ft | 62.1 µg/L |
| 59 | Vincent Lake | D | 5.4 ft | 15 ft | - |
| 60 | Horse Lake | D | 4.3 ft | 11 ft | - |
| 61 | Largon Lake | D | 2.5 ft | 10 ft | 55.8 µg/L |
| 62 | Apple River Flowage Lake | D | 5.9 ft | 18 ft | 78.5 µg/L |
| 63 | Omer Lake | D | 5 ft | - | 66.6 µg/L |
| 64 | Big Round Deep Hole South Lake | D | 4.9 ft | 17 ft | - |
| 65 | Big Blake Lake | D | 2.5 ft | 14 ft | 59.5 µg/L |
| 66 | Gibson Lake | D | - | 12 ft | 60.3 µg/L |
| 67 | Long Trade Lake | D | 3 ft | 13 ft | 87.6 µg/L |
| 68 | Mud Lake | D | 5.2 ft | 12 ft | 129 µg/L |
| 69 | White Ash Lake | D | 2.8 ft | 9 ft | 68.2 µg/L |
| 70 | Alabama Lake | D | 1.7 ft | 28 ft | 70.8 µg/L |
| 71 | Mud Lake | F | 2 ft | 7 ft | 93 µg/L |
| 72 | Unnamed Lake | F | 1.6 ft | - | - |
| 73 | Lotus Lake | F | 2 ft | 15 ft | - |
Source: EPA National Aquatic Resource Surveys, 2026.