Mark Lake
Cook County, Minnesota128 acresView mapDirections
No nutrient or algae sampling on record from Minnesota PCA for this lake.
- Impaired · Mercury
- 5 ft max depth
Mark Lake in Cook County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 4.9 ft. Surface area: 128 acres.
Mark Lake is a 128-acre lake in Cook County, Minnesota with a maximum depth of 5 feet.
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. Mark Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Mark 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 Mark Lake
These are the measurements Minnesota PCA publishes for Mark 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 Mark Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
4.9 ft
Surface area
128 acres
Shoreline
3.1 mi
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Stays near Mark Lake
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Fishing Mark Lake
EPA Impairment Status
Mark 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: Fish consumption.
A Total Maximum Daily Load (TMDL) plan has been approved.
Source: EPA ATTAINS assessment unit MN16-0250-00 · Official waterbody report
Nearby Lakes in Cook County
Frequently asked questions about Mark Lake
Where is Mark Lake?
- Mark 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 Mark Lake?
- Mark Lake in Cook County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 4.9 ft. Surface area: 128 acres.
Is Mark Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Mark Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
How deep is Mark Lake?
- Mark Lake has a maximum depth of 4.9 feet. The lake covers 128 acres.
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Where this data comes from
Measurements for Mark 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