Where is Flat Horn Lake?

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

How deep is Flat Horn Lake?

Flat Horn Lake has a maximum depth of 9.8 feet. The lake covers 50 acres.

Are there campgrounds on Flat Horn Lake?

Flat Horn Lake has 1 public campground from USGS The National Map within 5 km, including Little Isabella River Campground. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.

Flat Horn Lake

Lake County, Minnesota50 acresView map Directions

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

Max depth

9.8 ft

Bathymetric survey

Area

50 acres

Surface area

Shoreline

1.8 mi

Measured length

Impaired · Mercury
10 ft max depth

See the measurements Directions Where to stay

Flat Horn Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 9.8 ft. Surface area: 50 acres.

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Flat Horn Lake is a 50-acre lake in Lake 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.

What Flat Horn Lake is good for

From access and monitoring records, not editorial picks.

Camping1 public campground nearby

Swimming conditions

No reading

Not rated

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

Whether Flat Horn 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 Flat Horn Lake

These are the measurements Minnesota PCA publishes for Flat Horn 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 Flat Horn Lake

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

Lake Details

Max depth

9.8 ft

Surface area

50 acres

Shoreline

1.8 mi

Recreation & Access

Campgrounds

Public campgrounds near Flat Horn Lake

Little Isabella River Campground2.8 kmReserve

Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes

Stays via Stay22

Stays near Flat Horn Lake

Compare lakeside cabins, hotels, and vacation rentals near Flat Horn Lake in Lake 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 Flat Horn Lake

Prices for Oct 16–18, 4 adults. Change dates on the map below.

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Fishing Flat Horn Lake

→ Flat Horn Lake fishing regulations (limits, seasons, special rules)

EPA Impairment Status

Flat Horn 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 MN38-0568-00 · Official waterbody report

Nearby Lakes in Lake County

Gegoka Lake3.4 ft clear · Eutrophic1.2 miView →Grouse Lake6 ft clear1.8 miView →Mitawan Lake11.3 ft clear · Oligotrophic1.9 miView →Cat Lake2.5 miView →Ova Lake2.7 miView →Kitigan Lake2.5 miView →

Frequently asked questions about Flat Horn Lake

Where is Flat Horn Lake?: Flat Horn Lake is a lake in Lake County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Flat Horn Lake?: Flat Horn Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 9.8 ft. Surface area: 50 acres.
Is Flat Horn Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Flat Horn Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
How deep is Flat Horn Lake?: Flat Horn Lake has a maximum depth of 9.8 feet. The lake covers 50 acres.
Are there campgrounds on Flat Horn Lake?: Flat Horn Lake has 1 public campground from USGS The National Map within 5 km, including Little Isabella River Campground. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.