Where is McArthur Lake?

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

McArthur Lake

Boundary County, Idaho135 acresView map Directions

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

Area

135 acres

Surface area

Shoreline

4.3 mi

Measured length

Impaired · Mercury

See the measurements Directions Where to stay

McArthur Lake in Boundary County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Surface area: 135 acres.

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McArthur Lake is a 135-acre lake in Boundary County, Idaho.

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

Swimming conditions

No reading

Recreation use not supported

Nutrient and algae readings are not a swimming clearance. McArthur Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.

Whether McArthur Lake is safe to swim in today is a call for the Idaho 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 McArthur Lake

These are the measurements Idaho DEQ publishes for McArthur 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 McArthur Lake

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

Lake Details

Surface area

135 acres

Shoreline

4.3 mi

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

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Stays near McArthur Lake

Compare lakeside cabins, hotels, and vacation rentals near McArthur Lake in Boundary County, Idaho — 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 McArthur Lake

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

EPA Impairment Status

McArthur Lake is officially listed as impaired under Clean Water Act §303(d) in the 2022 EPA reporting cycle (IR category 5).

Causes of impairment

Mercury

Designated uses not supporting: Aquatic life, Recreation.

Source: EPA ATTAINS assessment unit ID17010104PN023_0L · Official waterbody report

Nearby Lakes in Boundary County

Harrison Lake14.7 miView →Smith Lake20.1 miView →Dawson Lake20.7 miView →Brush Lake—View →Herman Lake—View →Perkins Lake—View →

Frequently asked questions about McArthur Lake

Where is McArthur Lake?: McArthur Lake is a lake in Boundary County, Idaho. Its water-quality measurements are published by Idaho DEQ and shown on this page as reported.
What is the water quality of McArthur Lake?: McArthur Lake in Boundary County, Idaho has water-quality measurements published by Idaho DEQ, shown here as reported. Surface area: 135 acres.
Is McArthur Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. McArthur Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.