Saint Mary Lake
Glacier County, Montana3,964 acresView mapDirections
No nutrient or algae sampling on record from Montana DEQ for this lake.
Saint Mary Lake in Glacier County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 3964 acres.
Saint Mary Lake is a 3,964-acre lake in Glacier County, Montana.
Source: EPA Water Quality Portal sampling records, Montana DEQ. Methodology: how these readings are compared.
What Saint Mary Lake is good for
From access and monitoring records, not editorial picks.
- Camping1 public campground nearby
- Big water3,964 acres
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Saint Mary 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 Saint Mary Lake
These are the measurements Montana DEQ publishes for Saint Mary 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 Saint Mary Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
3,964 acres
Shoreline
24.4 mi
No bathymetric survey has been published for Saint Mary Lake, so its depth is not documented here.
Recreation & Access
Public campgrounds near Saint Mary Lake
- Rising Sun3.1 km
Nearest public campgrounds in the USGS National Map inventory, within about 3 miles. An empty list means USGS records no campground that close, which is not the same as camping being unavailable. Where the source gives an official reservation link, it is used; the cabin and hotel search does not cover campsites. More camping lakes
Stays via Stay22
Stays near Saint Mary Lake
Compare lakeside cabins, hotels, and vacation rentals near Saint Mary Lake in Glacier 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 Saint Mary Lake
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Fishing Saint Mary Lake
Nearby Lakes in Glacier County
Frequently asked questions about Saint Mary Lake
Where is Saint Mary Lake?
- Saint Mary Lake is a lake in Glacier County, Montana. Its water-quality measurements are published by Montana DEQ and shown on this page as reported.
What is the water quality of Saint Mary Lake?
- Saint Mary Lake in Glacier County, Montana has water-quality measurements published by Montana DEQ, shown here as reported. Surface area: 3964 acres.
Is Saint Mary Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Are there campgrounds on Saint Mary Lake?
- Saint Mary Lake has 1 public campground from USGS The National Map within 5 km, including Rising Sun. This is a location join, not a booking. Cabins and hotels are listed separately; campsite reservations use the official link when the source provides one.
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Where this data comes from
Measurements for Saint Mary Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Public campgrounds from USGS The National Map Structures, within about 3 miles