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Map of Lac Desmarais with depth contours

Lac Desmarais

46.1792° N, 74.6543° W

Depth contours from the 2011 government survey. Not for navigation.

Download the depth map (SVG)

Lac Desmarais, Quebec. 46.1792° N, 74.6543° W

Maximum depth 33 m (2011 survey). Scale bar on the map.

Not for navigation. Depths are from government surveys and may be outdated.

borealbound.ca/lakes/qc/lac-desmarais/, compiled October 9, 2026

  • Canadian Geographical Names Database, Natural Resources Canada. Contains information licensed under the Open Government Licence – Canada.
  • HydroLAKES v1.0, Messager et al. 2016 / WWF HydroSHEDS. Licensed under CC BY 4.0.
  • Census boundaries and population, 2021, Statistics Canada. Adapted from Statistics Canada. This does not constitute an endorsement by Statistics Canada.
  • Géobase des bathymétries de lac du Québec (GBLQ), Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs. Licensed under CC BY 4.0. Source: Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs (MELCCFP), Données Québec.
  • États trophiques des lacs (RSVL), Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs. Licensed under CC BY 4.0. Source: Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs (MELCCFP), Données Québec.
  • City page weather forecasts and alerts, Environment and Climate Change Canada. Contains data from Environment and Climate Change Canada (ECCC Data Servers End-use Licence).

Lac Desmarais is 33 m deep at its deepest point, deeper than 85% of the 1,506 surveyed lakes in Quebec. It covers 0.82 km² and lies 1 km northwest of Lac-Gélinas.

Maximum depth
33 msurveyed 2011
deeper than 85% of the 1,506 surveyed lakes in Quebec
Area
0.82 km²
larger than 71% of the 29,407 lakes in Quebec
Shoreline
6.3 km
longer than 68% of the 29,407 lakes in Quebec
Water clarity
8.3 mSecchi depth, 2025
clearer than 97% of the 805 monitored lakes in Quebec
Elevation
270 m

Today on the water

3.7 °C

Wind NE 3 km/h

Observed at Mont-Tremblant, as of 2:00 a.m. EDT

choppy Estimated waves, next 12 hours: up to 0.2 m.

Time3 a.m.6 a.m.9 a.m.12 p.m.3 p.m.6 p.m.9 p.m.12 a.m.
Wind km/hW 10W 10W 10W 20W 20W 10W 10NW 10
Waves (est.) m0.10.10.10.2
Temp. °C76799741
Precip. %6040404040000

Tonight: Partly cloudy with 60 percent chance of showers. Wind west 20 km/h becoming light this evening. Low 6.

Weather: Mont-Tremblant (local forecast), as of 2:02 a.m. EDT

Sun and moon

Civil dawn
6:37 a.m.
Sunrise
7:07 a.m.
Sunset
6:23 p.m.
Civil dusk
6:53 p.m.
Moonrise
5:58 a.m.
Moonset
5:41 p.m.
Moon
Waning crescent, 1% lit

Data Source: Environment and Climate Change Canada. Local times.

How waves are estimated

Significant wave height from the forecast hourly wind and the open-water distance (fetch) upwind, using the SMB method (US Army Corps of Engineers Shore Protection Manual, 1984), rounded up to the next 0.1 m. It is not a measurement: gusts, leftover swell and shoals can make water rougher. Under 0.2 m: calm; 0.2–0.5 m: choppy; over 0.5 m: rough.

Depth

78% of Lac Desmarais is deeper than 10 m.

How to read it: the lake’s area is sorted from the shore to the deepest point. Where the curve is flat, large areas share one depth (flats and weed beds); where it drops, depth changes quickly (drop-offs).

The government depth survey from 2011 records a maximum depth of 33 m, drawn from 38 depth contours.

Not for navigation. Depths are from government surveys and may be outdated.

Water

Trophic status from the latest monitoring: ultra-oligotrophic.

Clarity was measured with a Secchi disk in 13 years between 2009 and 2025; the latest annual mean is 8.3 m.

Water clarity (Secchi depth, m)
Total phosphorus (µg/L)