Loon Lake
Washington County, Minnesota51 acresView mapDirections
No nutrient or algae sampling on record from Minnesota PCA for this lake.
- Impaired · Nutrients (phosphorus, nitrogen)
- 13 ft max depth
Loon Lake in Washington County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 13.1 ft. Surface area: 51 acres.
Loon Lake is a 51-acre lake in Washington County, Minnesota with a maximum depth of 13 feet.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder. Methodology: how these readings are compared.
Swimming conditions
No readingRecreation use not supported
Nutrient and algae readings are not a swimming clearance. Loon Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Loon 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.
Water quality measurements for Loon Lake
These are the measurements Minnesota PCA publishes for Loon 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 Loon Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
13.1 ft
Surface area
51 acres
Shoreline
1.8 mi
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Fishing Loon Lake
EPA Impairment Status
Loon Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).
Causes of impairment
Designated uses not supporting: Recreation.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN82-0015-02 · Official waterbody report
Nearby Lakes in Washington County
Frequently asked questions about Loon Lake
Where is Loon Lake?
- Loon Lake is a lake in Washington County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Loon Lake?
- Loon Lake in Washington County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 13.1 ft. Surface area: 51 acres.
Is Loon Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Loon Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
How deep is Loon Lake?
- Loon Lake has a maximum depth of 13.1 feet. The lake covers 51 acres.
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Where this data comes from
Measurements for Loon Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database
Lake details from Minnesota DNR LakeFinder