Big McNeil Slough
Phillips County, Montana40 acresView mapDirections
No nutrient or algae sampling on record from Montana DEQ for this lake.
Big McNeil Slough in Phillips County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 40 acres.
Big McNeil Slough is a 40-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 Big McNeil Slough 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 Big McNeil Slough
These are the measurements Montana DEQ publishes for Big McNeil Slough, 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 Big McNeil Slough
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
40 acres
Shoreline
3.7 mi
No bathymetric survey has been published for Big McNeil Slough, so its depth is not documented here.
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Frequently asked questions about Big McNeil Slough
Where is Big McNeil Slough?
- Big McNeil Slough 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 Big McNeil Slough?
- Big McNeil Slough in Phillips County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 40 acres.
Is Big McNeil Slough 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 Big McNeil Slough come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.