Is Grand Lac Saint-FrançOis safe to swim in?

Good for swimming, clear water with low algae levels. Grand Lac Saint-FrançOis has an overall water quality grade of B. Algae concentration (chlorophyll-a) is 3.8 µg/L. Always check local health department advisories before swimming.

Le Granit County, Québec · Water Quality Report Card

Grand Lac Saint-FrançOis

Grade B — Good

Mesotrophic

Grand Lac Saint-FrançOis in Le Granit, Québec received a water quality grade of B (Good). Water clarity: 2.7 m visibility. Phosphorus: 9.8 µg/L. Chlorophyll-a (algae): 3.8 µg/L.

Clarity: 2.7 m
Type: Mesotrophic

Where to stay →Safe to swim?

Grand Lac Saint-FrançOis is a mesotrophic lake in Le Granit County, Québec. Water quality is graded B based on 3 sampling years through 2025. Compared to the 9 other monitored lakes in Le Granit County, Grand Lac Saint-FrançOis ranks #8 for water quality.

Source: EPA Water Quality Portal sampling records, MELCCFP, last sampled 2025-08-01. Grade methodology: LakeGrade methodology.

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Swimming Safety

Good for swimming, clear water with low algae levels

Water Quality Grade: B, Good

Moderate clarity, visible to about 8.9 ft. Phosphorus level: 9.8 µg/L. Chlorophyll-a: 3.8 µg/L. Trophic State Index: 42.

Metric	Value	Grade
Water Clarity (Secchi Depth)	2.7 m	C
Phosphorus	9.8 µg/L	A
Chlorophyll-a (Algae)	3.8 µg/L	A
Trophic State Index (TSI)	42	Mesotrophic

Moderate nutrients, good water quality

Where to stay near Grand Lac Saint-FrançOis

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