Flat Rock Lake
Carbon County, Montana41 acresView mapDirections
No nutrient or algae sampling on record from Montana DEQ for this lake.
- 85 ft max depth
Flat Rock Lake in Carbon County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Maximum depth: 85 ft. Surface area: 41 acres.
Flat Rock Lake is a 41-acre lake in Carbon County, Montana with a maximum depth of 85 feet.
Source: EPA Water Quality Portal sampling records, Montana DEQ. Methodology: how these readings are compared.
What Flat Rock Lake is good for
From access and monitoring records, not editorial picks.
- Deep water85 ft surveyed max depth
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Flat Rock 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 Flat Rock Lake
These are the measurements Montana DEQ publishes for Flat 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 Flat Rock Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
85 ft
Surface area
41 acres
Shoreline
1.2 mi
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Fishing Flat Rock Lake
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Frequently asked questions about Flat Rock Lake
Where is Flat Rock Lake?
- Flat Rock 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 Flat Rock Lake?
- Flat Rock Lake in Carbon County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Maximum depth: 85 ft. Surface area: 41 acres.
Is Flat Rock Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Flat Rock Lake?
- Flat Rock Lake has a maximum depth of 85 feet. The lake covers 41 acres.
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Where this data comes from
Measurements for Flat Rock Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.