Willow Flat Reservoir
Valley County, Montana26 acresView mapDirections
No nutrient or algae sampling on record from Montana DEQ for this lake.
Willow Flat Reservoir in Valley County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 26 acres.
Willow Flat Reservoir is a 26-acre lake in Valley 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 Willow Flat 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 Willow Flat Reservoir
These are the measurements Montana DEQ publishes for Willow Flat 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
26 acres
Shoreline
1 mi
No bathymetric survey has been published for Willow Flat Reservoir, so its depth is not documented here.
Stays via Stay22
Stays near Willow Flat Reservoir
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Frequently asked questions about Willow Flat Reservoir
Where is Willow Flat Reservoir?
- Willow Flat Reservoir is a lake in Valley County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Willow Flat Reservoir?
- Willow Flat Reservoir in Valley County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 26 acres.
Is Willow Flat 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 Willow Flat Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.