Rock Lake is a lake in Aitkin County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.

How deep is Rock Lake?

Rock Lake has a maximum depth of 13.1 feet. The lake covers 334 acres.

Rock Lake

Aitkin County, Minnesota334 acresView map Directions

No nutrient or algae sampling on record from Minnesota PCA for this lake.

Max depth

13.1 ft

Bathymetric survey

Area

334 acres

Surface area

Shoreline

5.2 mi

Measured length

Impaired · Mercury
13 ft max depth

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Rock Lake in Aitkin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 13.1 ft. Surface area: 334 acres.

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Rock Lake is a 334-acre lake in Aitkin County, Minnesota with a maximum depth of 13 feet.

Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder. Methodology: how these readings are compared.

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Rock Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. 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.

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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

13.1 ft

Surface area

334 acres

Shoreline

5.2 mi

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Stays near Rock Lake

Compare lakeside cabins, hotels, and vacation rentals near Rock Lake in Aitkin County, Minnesota — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.

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Fishing Rock Lake

→ Rock Lake fishing regulations (limits, seasons, special rules)

EPA Impairment Status

Rock Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 4A).

Causes of impairment

Mercury

Designated uses not supporting: Fish consumption.

A Total Maximum Daily Load (TMDL) plan has been approved.

Source: EPA ATTAINS assessment unit MN01-0072-00 · Official waterbody report

Nearby Lakes in Aitkin County

Bass Lake5 ft clear0.8 miView →Round Lake1.4 miView →Steamboat Lake2.3 ft clear1.3 miView →Davis Lake1.5 miView →Davis Lake1.6 ft clear1.5 miView →Turner Lake1.8 miView →

Frequently asked questions about Rock Lake

Where is Rock Lake?: Rock Lake is a lake in Aitkin 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 Aitkin County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 13.1 ft. Surface area: 334 acres.
Is Rock Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Rock Lake is listed impaired under Clean Water Act §303(d) (IR 4A) for mercury. Check local advisories before you swim.
How deep is Rock Lake?: Rock Lake has a maximum depth of 13.1 feet. The lake covers 334 acres.