Is Lac Siesta safe to swim in?

Good for swimming, clear water with low algae levels. Lac Siesta has an overall water quality grade of B. Algae concentration (chlorophyll-a) is 6.3 µg/L. Always check local health department advisories before swimming.

Montcalm County, Québec · Water Quality Report Card

Lac Siesta

Grade B — Good

Mesotrophic

Lac Siesta in Montcalm, Québec received a water quality grade of B (Good). Water clarity: 2.3 m visibility. Phosphorus: 8.5 µg/L. Chlorophyll-a (algae): 6.3 µg/L.

Clarity: 2.3 m
Type: Mesotrophic

Where to stay →Safe to swim?

Lac Siesta is a mesotrophic lake in Montcalm County, Québec. Water quality is graded B based on 3 sampling years through 2017. Compared to the 7 other monitored lakes in Montcalm County, Lac Siesta ranks #7 for water quality.

Source: EPA Water Quality Portal sampling records, MELCCFP, last sampled 2017-08-01. 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 7.5 ft. Phosphorus level: 8.5 µg/L. Chlorophyll-a: 6.3 µg/L. Trophic State Index: 44.

Metric	Value	Grade
Water Clarity (Secchi Depth)	2.3 m	C
Phosphorus	8.5 µg/L	A
Chlorophyll-a (Algae)	6.3 µg/L	B
Trophic State Index (TSI)	44	Mesotrophic

Moderate nutrients, good water quality

Where to stay near Lac Siesta

Compare lakeside cabins, hotels, and vacation rentals near Lac Siesta in Montcalm, Québec — 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.

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Fishing Lac Siesta

→ Lac Siesta fishing regulations (limits, seasons, special rules)

Location

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County Ranking

Ranked #7 of 8 lakes in Montcalm

Cleaner Lakes Within 30 Miles

Lac Siesta holds Grade B. 5 nearby lakes hold higher grades.

See full comparison →

Nearby Lakes in Montcalm

Explore Lac Siesta across LakeGrade

Lake Fishing Forecast

Species activity outlook by water temperature and season

Mesotrophic Lakes

Moderate nutrients, good water quality

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Grade A/B + low algae filter

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All Québec lakes

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Other Grade B Lakes in Québec

Matawinie · 2.5 m

Matawinie · 2.5 m

Matawinie · 2.2 m

Matawinie · 1.8 m

La Rivière-du-Nord · 2.9 m

Lac Chantelle

Matawinie · 2.6 m

Mesotrophic Lakes in Québec

Lac à Lunettes Lac Beaulne Lac Rawdon Lac Sur la Montagne

More records, surveys & data sources

Where this data comes from

Measurements for Lac Siesta come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.

Data Sources

Water quality data from the EPA Water Quality Portal

Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion

Most recent sample: 2017-08-01

Monitoring stations:

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