Lac des Trois Montagnes
46.1642° N, 74.7836° W
Depth contours from the 2011 government survey. Not for navigation.
Download the depth map (SVG)Lac des Trois Montagnes, Quebec. 46.1642° N, 74.7836° W
Maximum depth 68.7 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 Depths are from government surveys and may be outdated.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-des-trois-montagnes/, 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 des Trois Montagnes is 68.7 m deep at its deepest point, deeper than 98% of the 1,506 surveyed lakes in Quebec. It covers 3.28 km² and lies beside Lac-Simon.
- Maximum depth
- 68.7 msurveyed 2011
- deeper than 98% of the 1,506 surveyed lakes in Quebec
- Area
- 3.28 km²
- larger than 88% of the 29,407 lakes in Quebec
- Shoreline
- 17.7 km
- longer than 86% of the 29,407 lakes in Quebec
- Water clarity
- 7 mSecchi depth, 2025
- clearer than 92% of the 805 monitored lakes in Quebec
- Elevation
- 232 m
Today on the water
3.7 °C
Observed at Mont-Tremblant, as of 2:00 a.m. EDT
choppy Estimated waves, next 12 hours: up to 0.2 m.
| Time | 3 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/h | W 10 | W 10 | W 10 | W 20 | W 20 | W 10 | W 10 | NW 10 |
| Waves (est.) m | 0.1 | 0.1 | 0.1 | 0.2 | ||||
| Temp. °C | 7 | 6 | 7 | 9 | 9 | 7 | 4 | 1 |
| Precip. % | 60 | 40 | 40 | 40 | 40 | 0 | 0 | 0 |
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
- 6:38 a.m.
- Sunrise
- 7:08 a.m.
- Sunset
- 6:23 p.m.
- Civil dusk
- 6:53 p.m.
- Moonrise
- 5:59 a.m.
- Moonset
- 5:41 p.m.
- Moon
- Waning crescent, 1% lit
Follow this lake by email: a weekly summary of conditions.
Depth
29% of Lac des Trois Montagnes is deeper than 30 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 68.7 m, drawn from 42 depth contours.
- Download the depth map (SVG)Printing this page gives the map on one sheet, with scale and sources.
- Official government depth map (PDF)
Not for navigation. Depths are from government surveys and may be outdated.
Water
Trophic status from the latest monitoring: oligotrophic.
Clarity was measured with a Secchi disk in 22 years between 2004 and 2025; the latest annual mean is 7 m.
Follow this lake
Every Friday by email: the Environment Canada forecast and any weather alerts in effect.