Knife Lake
Lake County, Minnesota1,774 acresView mapDirections
No nutrient or algae sampling on record from Minnesota PCA for this lake.
- Impaired · Mercury
Knife Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Surface area: 1774 acres.
Knife Lake is a 1,774-acre lake in Lake County, Minnesota.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder. Methodology: how these readings are compared.
What Knife Lake is good for
From access and monitoring records, not editorial picks.
- Big water1,774 acres
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Knife Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
Whether Knife 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 Knife Lake
These are the measurements Minnesota PCA publishes for Knife 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 Knife Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
1,774 acres
Shoreline
31.7 mi
No bathymetric survey has been published for Knife Lake, so its depth is not documented here.
Stays via Stay22
Stays near Knife Lake
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Fishing Knife Lake
EPA Impairment Status
Knife 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 MN38-0404-00 · Official waterbody report
Nearby Lakes in Lake County
Frequently asked questions about Knife Lake
Where is Knife Lake?
- Knife 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 Knife Lake?
- Knife Lake in Lake County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Surface area: 1774 acres.
Is Knife Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Knife Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
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Where this data comes from
Measurements for Knife 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