Rock Lake
St. Louis County, Minnesota64 acresView mapDirections
No nutrient or algae sampling on record from Minnesota PCA for this lake.
- 50 ft max depth
Rock Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 49.9 ft. Surface area: 64 acres.
Rock Lake is a 64-acre lake in St. Louis County, Minnesota with a maximum depth of 50 feet.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder. Methodology: how these readings are compared.
What Rock Lake is good for
From access and monitoring records, not editorial picks.
- Deep water49.9 ft surveyed max depth
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Rock 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 Rock Lake
These are the measurements Minnesota PCA publishes for Rock 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 Rock Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
49.9 ft
Surface area
64 acres
Shoreline
1.9 mi
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Fishing Rock Lake
Nearby Lakes in St. Louis County
Frequently asked questions about Rock Lake
Where is Rock Lake?
- Rock Lake is a lake in St. Louis County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Rock Lake?
- Rock Lake in St. Louis County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 49.9 ft. Surface area: 64 acres.
Is Rock Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Rock Lake?
- Rock Lake has a maximum depth of 49.9 feet. The lake covers 64 acres.
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Where this data comes from
Measurements for Rock 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