Frethem Lake
Mahnomen County, Minnesota54 acresView mapDirections
No nutrient or algae sampling on record from Minnesota PCA for this lake.
Frethem Lake in Mahnomen County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Surface area: 54 acres.
Frethem Lake is a 54-acre lake in Mahnomen County, Minnesota.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder. Methodology: how these readings are compared.
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Frethem 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 Frethem Lake
These are the measurements Minnesota PCA publishes for Frethem 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 Frethem Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
54 acres
Shoreline
1.4 mi
No bathymetric survey has been published for Frethem Lake, so its depth is not documented here.
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Stays near Frethem Lake
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Fishing Frethem Lake
Nearby Lakes in Mahnomen County
Frequently asked questions about Frethem Lake
Where is Frethem Lake?
- Frethem Lake is a lake in Mahnomen County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Frethem Lake?
- Frethem Lake in Mahnomen County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Surface area: 54 acres.
Is Frethem Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
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Where this data comes from
Measurements for Frethem Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Lake details from Minnesota DNR LakeFinder