Where is Benton Lake?

Benton Lake is a lake in Cascade County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.

Benton Lake

Cascade County, Montana855 acresView map Directions

No nutrient or algae sampling on record from Montana DEQ for this lake.

Area

855 acres

Surface area

Impaired · Algal growth

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Benton Lake in Cascade County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 855 acres.

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Benton Lake is a 855-acre lake in Cascade County, Montana.

Source: EPA Water Quality Portal sampling records, Montana DEQ. Methodology: how these readings are compared.

Swimming conditions

No reading

Recreation use not supported

Nutrient and algae readings are not a swimming clearance. Benton Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, metals (other than mercury), nutrients (phosphorus, nitrogen), salinity / chlorides. Check local advisories before you swim.

Whether Benton Lake is safe to swim in today is a call for the Montana Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.

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Water quality measurements for Benton Lake

These are the measurements Montana DEQ publishes for Benton 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 Benton Lake

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

Lake Details

Surface area

855 acres

No bathymetric survey has been published for Benton Lake, so its depth is not documented here.

Stays via Stay22

Stays near Benton Lake

Compare lakeside cabins, hotels, and vacation rentals near Benton Lake in Cascade County, Montana — 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.

Top-rated places to stay near Benton Lake

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Fishing Benton Lake

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

EPA Impairment Status

Benton Lake is officially listed as impaired under Clean Water Act §303(d) in the 2021 EPA reporting cycle (IR category 5).

Causes of impairment

Algal growthMetals (other than mercury)Nutrients (phosphorus, nitrogen)Salinity / chlorides

Designated uses not supporting: Drinking water, Aquatic life, Recreation, Other.

Source: EPA ATTAINS assessment unit MT41Q005_020 · Official waterbody report

Nearby Lakes in Cascade County

Benton Lake0.5 miView →Benton Lake3.3 miView →Benton Lake3.9 miView →Benton Lake3.8 miView →Black Horse Lake4.1 miView →Benton Lake4.5 miView →

Frequently asked questions about Benton Lake

Where is Benton Lake?: Benton Lake is a lake in Cascade County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Benton Lake?: Benton Lake in Cascade County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 855 acres.
Is Benton Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Benton Lake is listed impaired under Clean Water Act §303(d) (IR 5) for algal growth, metals (other than mercury), nutrients (phosphorus, nitrogen), salinity / chlorides. Check local advisories before you swim.