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LakeGrade
Oligotrophic

Oligotrophic Lakes in Minnesota & Wisconsin

Low nutrients, clear water, excellent for swimming. 1,398 lakes (37% of all graded lakes).

LakeCountyStateGradeClarityDepth
East Fox LakeCrow WingMNA16.1 ft65 ft
Deep Portage LakeCassMNA15.4 ft105 ft
Little Wabana LakeItascaMNA23.8 ft57 ft
Clearwater LakeCookMNA30 ft65 ft
Clearwater LakeLakeMNA18 ft46 ft
Lower Hay LakeCrow WingMNA19 ft100 ft
Latoka LakeDouglasMNA19 ft108 ft
Bad Medicine LakeBeckerMNA25 ft84 ft
Big Sugar Bush LakeBeckerMNA17 ft42 ft
Fullers Lake: East BasinBeltramiMNA49.2 ft
Birch LakeCookMNA18 ft69 ft
Birch LakeUnknownMNA15 ft34 ft
Round LakeAitkinMNA15.3 ft59 ft
Round LakeCookMNA16.5 ft45 ft
Round LakeBeltramiMNA59.1 ft
Pike LakeCookMNA17.8 ft45 ft
Pike LakeSt. LouisMNA18 ft60 ft
Horseshoe LakeCassMNA21 ft51 ft
Long LakeClearwaterMNA20 ft80 ft
Long LakeCassMNA21.8 ft115 ft
Long LakeBeltramiMNA20 ft87 ft
Long LakeBeckerMNA20 ft61 ft
Long LakeCassMNA16.8 ft37 ft
Long LakeBeltramiMNA45.9 ft
Long LakeItascaMNA16.7 ft72 ft
Long LakeItascaMNA16.9 ft85 ft
Dead LakeHubbardMNA16 ft34 ft
Unnamed LakeOtter TailMNA15.1 ft95 ft
Maple LakeItascaMNA15.3 ft39 ft
West Twin LakeCrow WingMNA19.8 ft
Sunshine LakeSt. LouisMNA20 ft37 ft
Shallow LakeItascaMNA16.4 ft85 ft
Trout LakeItascaMNA15.5 ft135 ft
Trout LakeItascaMNA18 ft157 ft
Trout LakeCookMNA19 ft77 ft
Otter LakeOtter TailMNA18 ft64 ft
Eddy LakeLakeMNA16.5 ft95 ft
Cowdry LakeDouglasMNA17 ft52 ft
Ossawinnamakee LakeCrow WingMNA20 ft63 ft
Clear LakeCrow WingMNA18 ft63 ft
Clear LakeAitkinMNA16 ft24 ft
Clear LakeItascaMNA14.9 ft30 ft
Bear LakeLakeMNA17.4 ft31 ft
Emerald LakeBeltramiMNA31.2 ft
Blue LakeHubbardMNA17.4 ft84 ft
Blue LakeCrow WingMNA19 ft48 ft
Eagle LakeOtter TailMNA22.6 ft46 ft
West Fox LakeCrow WingMNA15 ft55 ft
Spearhead LakeHubbardMNA15 ft81 ft
Ida LakeDouglasMNA16.5 ft106 ft
Star LakeCrow WingMNA19 ft83 ft
Star LakeOtter TailMNA16.7 ft94 ft
Upper Maple LakeWrightMNA18 ft76 ft
Partridge LakeCrow WingMNA16.2 ft42 ft
Fish LakeOtter TailMNA17.8 ft69 ft
Sand LakeCassMNA21 ft54 ft
Jenny LakeLakeMNA15.5 ft93 ft
Roger LakeCrow WingMNA16 ft64 ft
Hamlet LakeCrow WingMNA18.5 ft88 ft
Square LakeWashingtonMNA17 ft68 ft
Shell LakeBeltramiMNA42.7 ft
Tofte LakeLakeMNA18.5 ft73 ft
Andrusia LakeBeltramiMNA15.5 ft60 ft
Green LakeBeltramiMNA60.7 ft
Green LakeBeltramiMNA39.4 ft
Girl LakeCassMNA17 ft81 ft
Charlotte LakeWrightMNA17.1 ft46 ft
Big Mcdonald LakeOtter TailMNA16.4 ft46 ft
Bass LakeOtter TailMNA16.9 ft
Bass LakeCrow WingMNA16.1 ft47 ft
Bass LakeItascaMNA18.2 ft65 ft
Bass LakeCassMNA55 ft
Island LakeCassMNA15 ft45 ft
Island LakeCrow WingMNA15.3 ft76 ft
Island LakeCassMNA17.5 ft40 ft
Island LakeBeltramiMNA52.5 ft
Island LakeHubbardMNA16.4 ft32 ft
Crooked LakeHubbardMNA19.2 ft
Crooked LakeCrow WingMNA15 ft54 ft
Portage LakeCassMNA22.8 ft84 ft
Cedar LakeMorrisonMNA16.4 ft88 ft
Big Pine LakeAitkinMNA16.5 ft78 ft
Lizzie LakeOtter TailMNA16.4 ft66 ft
Eagles Nest LakeSt. LouisMNA15.5 ft49 ft
Turtle LakeBeckerMNA23 ft73 ft
Turtle LakeItascaMNA17.1 ft54 ft
Lower Bottle LakeHubbardMNA15 ft110 ft
Pokegama LakeItascaMNA16 ft112 ft
Sandy LakeBeltramiMNA52.5 ft
Pickerel LakeBeckerMNA18 ft74 ft
Pickerel LakeClearwaterMNA16.1 ft60 ft
Strawberry LakeBeckerMNA17.8 ft40 ft
Middle Cormorant LakeBeckerMNA15.1 ft40 ft
Mcavity LakeItascaMNA17 ft29 ft
Gull LakeCookMNA16.4 ft
Upper Bottle LakeHubbardMNA16 ft55 ft
Devil'S LakeOtter TailMNA15 ft67 ft
Hand LakeCassMNA17 ft57 ft
Ox Yoke LakeCassMNA17.5 ft42 ft
Ottertrack LakeUnknownMNA20.7 ft116 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.