Altermatt Lake
Brown County, Minnesota125 acresView mapDirections
No nutrient or algae sampling on record from Minnesota PCA for this lake.
- Impaired · Nutrients (phosphorus, nitrogen)
- 4 ft max depth
Altermatt Lake in Brown County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 4.4 ft. Surface area: 125 acres.
Altermatt Lake is a 125-acre lake in Brown County, Minnesota with a maximum depth of 4 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. Altermatt Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for nutrients (phosphorus, nitrogen). Check local advisories before you swim.
Whether Altermatt 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 Altermatt Lake
These are the measurements Minnesota PCA publishes for Altermatt 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 Altermatt Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
4.4 ft
Surface area
125 acres
Shoreline
2.3 mi
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Fishing Altermatt Lake
EPA Impairment Status
Altermatt 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 MN08-0054-00 · Official waterbody report
Nearby Lakes in Brown County
Frequently asked questions about Altermatt Lake
Where is Altermatt Lake?
- Altermatt Lake is a lake in Brown County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Altermatt Lake?
- Altermatt Lake in Brown County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 4.4 ft. Surface area: 125 acres.
Is Altermatt Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Altermatt 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 Altermatt Lake?
- Altermatt Lake has a maximum depth of 4.4 feet. The lake covers 125 acres.
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Where this data comes from
Measurements for Altermatt 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