Arch Lake
Carbon County, Montana50 acresView mapDirections
No nutrient or algae sampling on record from Montana DEQ for this lake.
Arch Lake in Carbon County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 50 acres.
Arch Lake is a 50-acre lake in Carbon County, Montana.
Source: EPA Water Quality Portal sampling records, Montana DEQ. Methodology: how these readings are compared.
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Arch 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.
Water quality measurements for Arch Lake
These are the measurements Montana DEQ publishes for Arch 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 Arch Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
50 acres
Shoreline
1.6 mi
No bathymetric survey has been published for Arch Lake, so its depth is not documented here.
Stays via Stay22
Stays near Arch Lake
Compare lakeside cabins, hotels, and vacation rentals near Arch Lake in Carbon 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.
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Frequently asked questions about Arch Lake
Where is Arch Lake?
- Arch Lake is a lake in Carbon County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Arch Lake?
- Arch Lake in Carbon County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 50 acres.
Is Arch Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
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Where this data comes from
Measurements for Arch Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.