Otter Lake is a lake in Cook County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.

How deep is Otter Lake?

Otter Lake has a maximum depth of 9.8 feet. The lake covers 75 acres.

Otter Lake

Cook County, Minnesota75 acresView map Directions

No nutrient or algae sampling on record from Minnesota PCA for this lake.

Max depth

9.8 ft

Bathymetric survey

Area

75 acres

Surface area

Shoreline

1.8 mi

Measured length

Impaired · Mercury
10 ft max depth

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Otter Lake in Cook County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 9.8 ft. Surface area: 75 acres.

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Otter Lake is a 75-acre lake in Cook County, Minnesota with a maximum depth of 10 feet.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder. Methodology: how these readings are compared.

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Otter Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.

Whether Otter Lake is safe to swim in today is a call for the Minnesota Pollution Control Agency and the Minnesota DNR and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Otter Lake

These are the measurements Minnesota PCA publishes for Otter Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.

No clarity data. TSI undefined.

Ask about Otter Lake

Answers come straight from the public measurements and survey records on this page.

Lake Details

Max depth

9.8 ft

Surface area

75 acres

Shoreline

1.8 mi

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Stays near Otter Lake

Compare lakeside cabins, hotels, and vacation rentals near Otter Lake in Cook County, Minnesota — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.

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Fishing Otter Lake

→ Otter Lake fishing regulations (limits, seasons, special rules)

EPA Impairment Status

Otter Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).

Causes of impairment

Mercury

Designated uses not supporting: Fish consumption.

Source: EPA ATTAINS assessment unit MN16-0032-00 · Official waterbody report

Nearby Lakes in Cook County

Royal Lake4.4 miView →Powers Lake3.6 miView →Chester Lake11.9 ft clear3.6 miView →Little John Lake—View →North Fowl Lake—View →Tom Lake9 ft clear · Mesotrophic—View →

Frequently asked questions about Otter Lake

Where is Otter Lake?: Otter Lake is a lake in Cook County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Otter Lake?: Otter Lake in Cook County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 9.8 ft. Surface area: 75 acres.
Is Otter Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Otter Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
How deep is Otter Lake?: Otter Lake has a maximum depth of 9.8 feet. The lake covers 75 acres.