Where is McWilliams Reservoir?

McWilliams Reservoir is a lake in Garfield County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.

McWilliams Reservoir

Garfield County, Montana107 acresView map Directions

No nutrient or algae sampling on record from Montana DEQ for this lake.

Area

107 acres

Surface area

See the measurements Directions Where to stay

McWilliams Reservoir in Garfield County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 107 acres.

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McWilliams Reservoir is a 107-acre lake in Garfield County, Montana.

Source: EPA Water Quality Portal sampling records, Montana DEQ. Methodology: how these readings are compared.

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.

Whether McWilliams 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.

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Water quality measurements for McWilliams Reservoir

These are the measurements Montana DEQ publishes for McWilliams 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.

Ask about McWilliams Reservoir

Answers come straight from the public measurements and survey records on this page.

Lake Details

Surface area

107 acres

No bathymetric survey has been published for McWilliams Reservoir, so its depth is not documented here.

Stays via Stay22

Stays near McWilliams Reservoir

Compare lakeside cabins, hotels, and vacation rentals near McWilliams Reservoir in Garfield 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.

Top-rated places to stay near McWilliams Reservoir

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Fishing McWilliams Reservoir

→ McWilliams Reservoir fishing regulations (limits, seasons, special rules)

Nearby Lakes in Garfield County

Clear Water Reservoir7.9 miView →Murnions Reservoir27.5 miView →McKrone Reservoir—View →Wheatcroft Reservoir—View →Krieder Reservoir—View →Fort Peck Lake—View →

Frequently asked questions about McWilliams Reservoir

Where is McWilliams Reservoir?: McWilliams Reservoir is a lake in Garfield County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of McWilliams Reservoir?: McWilliams Reservoir in Garfield County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 107 acres.
Is McWilliams Reservoir safe to swim in?: Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.