Marathon Lake
Lake County, Minnesota35 acresView mapDirections
No nutrient or algae sampling on record from Minnesota PCA for this lake.
Marathon Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Surface area: 35 acres.
Marathon Lake is a 35-acre lake in Lake 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 Marathon 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 Marathon Lake
These are the measurements Minnesota PCA publishes for Marathon 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 Marathon Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
35 acres
Shoreline
1 mi
No bathymetric survey has been published for Marathon Lake, so its depth is not documented here.
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Stays near Marathon Lake
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Fishing Marathon Lake
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Frequently asked questions about Marathon Lake
Where is Marathon Lake?
- Marathon 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 Marathon Lake?
- Marathon Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Surface area: 35 acres.
Is Marathon 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 Marathon 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