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

How deep is Agate Lake?

Agate Lake has a maximum depth of 11.9 feet. The lake covers 154 acres.

Agate Lake

Cass County, Minnesota154 acresView map Directions

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

Max depth

11.9 ft

Bathymetric survey

Area

154 acres

Surface area

Shoreline

1.9 mi

Measured length

Impaired · Mercury
12 ft max depth

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Agate Lake in Cass County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 11.9 ft. Surface area: 154 acres.

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Agate Lake is a 154-acre lake in Cass County, Minnesota with a maximum depth of 12 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. Agate Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.

Whether Agate 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 Agate Lake

These are the measurements Minnesota PCA publishes for Agate 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.

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Answers come straight from the public measurements and survey records on this page.

Lake Details

Max depth

11.9 ft

Surface area

154 acres

Shoreline

1.9 mi

The depth above comes from a bathymetric survey of this lake, not from a regional estimate.

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Stays near Agate Lake

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Fishing Agate Lake

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

EPA Impairment Status

Agate Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).

Causes of impairment

Mercury

Designated uses not supporting: Fish consumption.

Source: EPA ATTAINS assessment unit MN11-0216-00 · Official waterbody report

Nearby Lakes in Cass County

Gull Lake15 ft clear · Mesotrophic1.3 miView →Margaret Lake5.5 ft clear · Eutrophic2.8 miView →Ruth Lake2.7 miView →Duffney Lake2.9 miView →Shafer Lake2.9 miView →Spider Lake—View →

Frequently asked questions about Agate Lake

Where is Agate Lake?: Agate Lake is a lake in Cass County, Minnesota. Its water-quality measurements are published by Minnesota PCA and shown on this page as reported.
What is the water quality of Agate Lake?: Agate Lake in Cass County, Minnesota has water-quality measurements published by Minnesota PCA, shown here as reported. Maximum depth: 11.9 ft. Surface area: 154 acres.
Is Agate Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Agate Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
How deep is Agate Lake?: Agate Lake has a maximum depth of 11.9 feet. The lake covers 154 acres.