St. Mary's Lake
St. Mary River, British ColumbiaView mapDirections
ENV publishes the water-quality measurements for St. Mary's Lake. Here is what has been measured.
- Limited data
St. Mary's Lake in St. Mary River, British Columbia has water-quality measurements published by ENV, shown here as reported. Water clarity: 3.4 m visibility. Phosphorus: 7.4 µg/L. Chlorophyll-a (algae): 0.5 µg/L.
St. Mary's Lake is a lake in St. Mary River County, British Columbia.
Source: the British Columbia Ministry of Environment and Parks — not the EPA Water Quality Portal, last sampled 2017-08-24. Methodology: how these readings are compared.
What St. Mary's Lake is good for
From access and monitoring records, not editorial picks.
- Clear water11.1 ft of visibility
Swimming conditions
No readingLimited data
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether St. Mary's Lake is safe to swim in today is a call for the British Columbia Ministry of Environment and Parks and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for St. Mary's Lake
These are the measurements ENV publishes for St. Mary's Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
Good clarity, visible to about 11.1 ft. Phosphorus 7.4 µg/L. Chlorophyll-a 0.5 µg/L. TSI 33.
| Measure | Reading | Where it sits |
|---|---|---|
| Water clarity (Secchi depth) | 3.38m | Measured, not scored How deep a black-and-white disk stays visible from the surface. Higher is clearer. |
| Total phosphorus | 7.4µg/L | Measured, not scored The nutrient that most limits algae growth in freshwater. More phosphorus, more algae potential. |
| Chlorophyll-a (algae) | 0.5µg/L | Measured, not scored The green pigment in algae — a direct measure of how much algae is in the water. |
| Trophic state (TSI)Carlson's 0–100 index of how much algae a lake can support, from clarity, phosphorus and chlorophyll-a. | 33 | Oligotrophic OligotrophicMesotrophicEutrophicHypereutrophic |
Low nutrients, clear water. No reading is a swimming clearance.
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Answers come straight from the public measurements and survey records on this page.
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Frequently asked questions about St. Mary's Lake
Where is St. Mary's Lake?
- St. Mary's Lake is a lake in St. Mary River, British Columbia. Its water-quality measurements are published by ENV and shown on this page as reported.
What is the water quality of St. Mary's Lake?
- St. Mary's Lake in St. Mary River, British Columbia has water-quality measurements published by ENV, shown here as reported. Water clarity: 3.4 m visibility. Phosphorus: 7.4 µg/L. Chlorophyll-a (algae): 0.5 µg/L.
Is St. Mary's Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Explore St. Mary's Lake across LakeQuality
More lakes in British Columbia
Other Lakes in British Columbia
Oligotrophic Lakes in British Columbia
Where this data comes from
6 measurements from 1 monitoring station, 2017. Retrieved from British Columbia EnMoDS (not the EPA Water Quality Portal) on 2026-09-06.
Collected and reported by
- British Columbia Ministry of Environment and Parks
enmods-bc6 samples · 2017
Monitoring station identifiers (1)
E308528
Canadian lakes are published with the measurements their provincial programme reports. See where the data comes from and data sources.