Frenchman Reservoir
Phillips County, Montana570 acresView mapDirections
No nutrient or algae sampling on record from Montana DEQ for this lake.
Frenchman Reservoir in Phillips County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 570 acres.
Frenchman Reservoir is a 570-acre lake in Phillips 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 Frenchman Reservoir 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 Frenchman Reservoir
These are the measurements Montana DEQ publishes for Frenchman Reservoir, 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
Surface area
570 acres
Shoreline
7.5 mi
No bathymetric survey has been published for Frenchman Reservoir, so its depth is not documented here.
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Stays near Frenchman Reservoir
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Frequently asked questions about Frenchman Reservoir
Where is Frenchman Reservoir?
- Frenchman Reservoir is a lake in Phillips County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Frenchman Reservoir?
- Frenchman Reservoir in Phillips County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 570 acres.
Is Frenchman Reservoir 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 Frenchman Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.