Thelma Lake
Cook County, Minnesota67 acresView mapDirections
No nutrient or algae sampling on record from Minnesota PCA for this lake.
Thelma Lake in Cook County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Surface area: 67 acres.
Thelma Lake is a 67-acre lake in Cook 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 Thelma 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 Thelma Lake
These are the measurements Minnesota PCA publishes for Thelma 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 Thelma Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
67 acres
Shoreline
2.5 mi
No bathymetric survey has been published for Thelma Lake, so its depth is not documented here.
Stays via Stay22
Stays near Thelma Lake
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Fishing Thelma Lake
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Frequently asked questions about Thelma Lake
Where is Thelma Lake?
- Thelma Lake is a lake in Cook County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Thelma Lake?
- Thelma Lake in Cook County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Surface area: 67 acres.
Is Thelma 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 Thelma 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