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

How deep is Lost Lake?

Lost Lake has a maximum depth of 19.7 feet. The lake covers 735 acres.

Are there boat ramps on Lost Lake?

Lost Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lost Lake. Public access is listed as yes.

Can I fish at Lost Lake?

Lost Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.

Lost Lake

St. Louis County, Minnesota735 acresView map Directions

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

Max depth

19.7 ft

Bathymetric survey

Area

735 acres

Surface area

Shoreline

4.8 mi

Measured length

Impaired · Mercury
20 ft max depth
Public access

See the measurements Directions Where to stay

Lost Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 19.7 ft. Surface area: 735 acres.

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Lost Lake is a 735-acre lake in St. Louis County, Minnesota with a maximum depth of 20 feet. Limited fish-species data available. Public access is available with 1 public boat landing.

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

What Lost Lake is good for

From access and monitoring records, not editorial picks.

Boat launch1 documented ramp

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Lost Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.

Whether Lost 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 Lost Lake

These are the measurements Minnesota PCA publishes for Lost 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 Lost Lake

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

Lake Details

Max depth

19.7 ft

Surface area

735 acres

Shoreline

4.8 mi

Public access

Yes

Listed by Minnesota PCA

Recreation & Access

Boat Landings

Yes

Public Access

Lost LakePublic

Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps

Stays via Stay22

Stays near Lost Lake

Compare lakeside cabins, hotels, and vacation rentals near Lost Lake in St. Louis 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.

Top-rated places to stay near Lost Lake

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Fishing Lost Lake

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

EPA Impairment Status

Lost Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).

Causes of impairment

Mercury

Designated uses not supporting: Fish consumption.

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit MN69-0581-00 · Official waterbody report

Nearby Lakes in St. Louis County

Pike River Flowage3.1 miView →Pike River Lake3.1 miView →Bass Lake4.2 ft clear4.9 miView →East Vermilion Lake6.5 ft clear5.3 miView →Pfeiffer Lake6 miView →Vermilion Lake3.5 ft clear4.9 miView →

Frequently asked questions about Lost Lake

Where is Lost Lake?: Lost Lake is a lake in St. Louis County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Lost Lake?: Lost Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 19.7 ft. Surface area: 735 acres.
Is Lost Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Lost Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
How deep is Lost Lake?: Lost Lake has a maximum depth of 19.7 feet. The lake covers 735 acres.
Are there boat ramps on Lost Lake?: Lost Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Lost Lake. Public access is listed as yes.
Can I fish at Lost Lake?: Lost Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Seasons, size and bag limits, and whether you need a license are set by Minnesota's fish and wildlife agency, so check its current regulations before you go.