Oligotrophic
Oligotrophic Lakes in Minnesota & Wisconsin
Low nutrients, clear water, excellent for swimming. 1,398 lakes (37% of all graded lakes).
| Lake | County | State | Grade | Clarity | Depth |
|---|---|---|---|---|---|
| East Fox Lake | Crow Wing | MN | A | 16.1 ft | 65 ft |
| Deep Portage Lake | Cass | MN | A | 15.4 ft | 105 ft |
| Little Wabana Lake | Itasca | MN | A | 23.8 ft | 57 ft |
| Clearwater Lake | Cook | MN | A | 30 ft | 65 ft |
| Clearwater Lake | Lake | MN | A | 18 ft | 46 ft |
| Lower Hay Lake | Crow Wing | MN | A | 19 ft | 100 ft |
| Latoka Lake | Douglas | MN | A | 19 ft | 108 ft |
| Bad Medicine Lake | Becker | MN | A | 25 ft | 84 ft |
| Big Sugar Bush Lake | Becker | MN | A | 17 ft | 42 ft |
| Fullers Lake: East Basin | Beltrami | MN | A | 49.2 ft | — |
| Birch Lake | Cook | MN | A | 18 ft | 69 ft |
| Birch Lake | Unknown | MN | A | 15 ft | 34 ft |
| Round Lake | Aitkin | MN | A | 15.3 ft | 59 ft |
| Round Lake | Cook | MN | A | 16.5 ft | 45 ft |
| Round Lake | Beltrami | MN | A | 59.1 ft | — |
| Pike Lake | Cook | MN | A | 17.8 ft | 45 ft |
| Pike Lake | St. Louis | MN | A | 18 ft | 60 ft |
| Horseshoe Lake | Cass | MN | A | 21 ft | 51 ft |
| Long Lake | Clearwater | MN | A | 20 ft | 80 ft |
| Long Lake | Cass | MN | A | 21.8 ft | 115 ft |
| Long Lake | Beltrami | MN | A | 20 ft | 87 ft |
| Long Lake | Becker | MN | A | 20 ft | 61 ft |
| Long Lake | Cass | MN | A | 16.8 ft | 37 ft |
| Long Lake | Beltrami | MN | A | 45.9 ft | — |
| Long Lake | Itasca | MN | A | 16.7 ft | 72 ft |
| Long Lake | Itasca | MN | A | 16.9 ft | 85 ft |
| Dead Lake | Hubbard | MN | A | 16 ft | 34 ft |
| Unnamed Lake | Otter Tail | MN | A | 15.1 ft | 95 ft |
| Maple Lake | Itasca | MN | A | 15.3 ft | 39 ft |
| West Twin Lake | Crow Wing | MN | A | 19.8 ft | — |
| Sunshine Lake | St. Louis | MN | A | 20 ft | 37 ft |
| Shallow Lake | Itasca | MN | A | 16.4 ft | 85 ft |
| Trout Lake | Itasca | MN | A | 15.5 ft | 135 ft |
| Trout Lake | Itasca | MN | A | 18 ft | 157 ft |
| Trout Lake | Cook | MN | A | 19 ft | 77 ft |
| Otter Lake | Otter Tail | MN | A | 18 ft | 64 ft |
| Eddy Lake | Lake | MN | A | 16.5 ft | 95 ft |
| Cowdry Lake | Douglas | MN | A | 17 ft | 52 ft |
| Ossawinnamakee Lake | Crow Wing | MN | A | 20 ft | 63 ft |
| Clear Lake | Crow Wing | MN | A | 18 ft | 63 ft |
| Clear Lake | Aitkin | MN | A | 16 ft | 24 ft |
| Clear Lake | Itasca | MN | A | 14.9 ft | 30 ft |
| Bear Lake | Lake | MN | A | 17.4 ft | 31 ft |
| Emerald Lake | Beltrami | MN | A | 31.2 ft | — |
| Blue Lake | Hubbard | MN | A | 17.4 ft | 84 ft |
| Blue Lake | Crow Wing | MN | A | 19 ft | 48 ft |
| Eagle Lake | Otter Tail | MN | A | 22.6 ft | 46 ft |
| West Fox Lake | Crow Wing | MN | A | 15 ft | 55 ft |
| Spearhead Lake | Hubbard | MN | A | 15 ft | 81 ft |
| Ida Lake | Douglas | MN | A | 16.5 ft | 106 ft |
| Star Lake | Crow Wing | MN | A | 19 ft | 83 ft |
| Star Lake | Otter Tail | MN | A | 16.7 ft | 94 ft |
| Upper Maple Lake | Wright | MN | A | 18 ft | 76 ft |
| Partridge Lake | Crow Wing | MN | A | 16.2 ft | 42 ft |
| Fish Lake | Otter Tail | MN | A | 17.8 ft | 69 ft |
| Sand Lake | Cass | MN | A | 21 ft | 54 ft |
| Jenny Lake | Lake | MN | A | 15.5 ft | 93 ft |
| Roger Lake | Crow Wing | MN | A | 16 ft | 64 ft |
| Hamlet Lake | Crow Wing | MN | A | 18.5 ft | 88 ft |
| Square Lake | Washington | MN | A | 17 ft | 68 ft |
| Shell Lake | Beltrami | MN | A | 42.7 ft | — |
| Tofte Lake | Lake | MN | A | 18.5 ft | 73 ft |
| Andrusia Lake | Beltrami | MN | A | 15.5 ft | 60 ft |
| Green Lake | Beltrami | MN | A | 60.7 ft | — |
| Green Lake | Beltrami | MN | A | 39.4 ft | — |
| Girl Lake | Cass | MN | A | 17 ft | 81 ft |
| Charlotte Lake | Wright | MN | A | 17.1 ft | 46 ft |
| Big Mcdonald Lake | Otter Tail | MN | A | 16.4 ft | 46 ft |
| Bass Lake | Otter Tail | MN | A | 16.9 ft | — |
| Bass Lake | Crow Wing | MN | A | 16.1 ft | 47 ft |
| Bass Lake | Itasca | MN | A | 18.2 ft | 65 ft |
| Bass Lake | Cass | MN | A | — | 55 ft |
| Island Lake | Cass | MN | A | 15 ft | 45 ft |
| Island Lake | Crow Wing | MN | A | 15.3 ft | 76 ft |
| Island Lake | Cass | MN | A | 17.5 ft | 40 ft |
| Island Lake | Beltrami | MN | A | 52.5 ft | — |
| Island Lake | Hubbard | MN | A | 16.4 ft | 32 ft |
| Crooked Lake | Hubbard | MN | A | 19.2 ft | — |
| Crooked Lake | Crow Wing | MN | A | 15 ft | 54 ft |
| Portage Lake | Cass | MN | A | 22.8 ft | 84 ft |
| Cedar Lake | Morrison | MN | A | 16.4 ft | 88 ft |
| Big Pine Lake | Aitkin | MN | A | 16.5 ft | 78 ft |
| Lizzie Lake | Otter Tail | MN | A | 16.4 ft | 66 ft |
| Eagles Nest Lake | St. Louis | MN | A | 15.5 ft | 49 ft |
| Turtle Lake | Becker | MN | A | 23 ft | 73 ft |
| Turtle Lake | Itasca | MN | A | 17.1 ft | 54 ft |
| Lower Bottle Lake | Hubbard | MN | A | 15 ft | 110 ft |
| Pokegama Lake | Itasca | MN | A | 16 ft | 112 ft |
| Sandy Lake | Beltrami | MN | A | 52.5 ft | — |
| Pickerel Lake | Becker | MN | A | 18 ft | 74 ft |
| Pickerel Lake | Clearwater | MN | A | 16.1 ft | 60 ft |
| Strawberry Lake | Becker | MN | A | 17.8 ft | 40 ft |
| Middle Cormorant Lake | Becker | MN | A | 15.1 ft | 40 ft |
| Mcavity Lake | Itasca | MN | A | 17 ft | 29 ft |
| Gull Lake | Cook | MN | A | 16.4 ft | — |
| Upper Bottle Lake | Hubbard | MN | A | 16 ft | 55 ft |
| Devil'S Lake | Otter Tail | MN | A | 15 ft | 67 ft |
| Hand Lake | Cass | MN | A | 17 ft | 57 ft |
| Ox Yoke Lake | Cass | MN | A | 17.5 ft | 42 ft |
| Ottertrack Lake | Unknown | MN | A | 20.7 ft | 116 ft |
Showing 100 of 1,398 oligotrophic lakes.
Frequently Asked Questions
What is an oligotrophic lake?
Low nutrients, clear water, excellent for swimming. There are 1,398 oligotrophic lakes in Minnesota and Wisconsin, representing 37% of all graded lakes.
Can you swim in oligotrophic lakes?
Oligotrophic lakes are excellent for swimming — they have crystal clear water with minimal algae and very low nutrient levels.