Lac Thor
45.7782° N, 71.2343° W
Depth contours from the government survey. Not for navigation.
Download the depth map (SVG)Lac Thor, Quebec. 45.7782° N, 71.2343° W
Maximum depth 10.9 m. Scale bar on the map.
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/qc/lac-thor/, 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).
- Photographs, Wikimedia Commons contributors. Each photo carries its own licence (CC0, public domain, CC BY or CC BY-SA), credited where shown.
Lac Thor is 10.9 m deep at its deepest point, shallower than 70% of the 1,506 surveyed lakes in Quebec. It covers 1.79 km² and lies 7.7 km northeast of Lac-Elgin.
- Maximum depth
- 10.9 m
- shallower than 70% of the 1,506 surveyed lakes in Quebec
- Area
- 1.79 km²
- larger than 82% of the 29,407 lakes in Quebec
- Shoreline
- 7 km
- longer than 71% of the 29,407 lakes in Quebec
- Water clarity
- 4.5 mSecchi depth, 2025
- clearer than 62% of the 805 monitored lakes in Quebec
- Elevation
- 295 m
Today on the water
4.6 °C
Observed at Thetford Mines, as of 4:00 a.m. EDT
choppy Estimated waves, next 12 hours: up to 0.2 m. Around 9 a.m., wind from the west: the west shore is sheltered, waves build toward the east shore.
| Time | 5 a.m. | 8 a.m. | 11 a.m. | 2 p.m. | 5 p.m. | 8 p.m. | 11 p.m. | 2 a.m. |
|---|---|---|---|---|---|---|---|---|
| Wind km/h | W 10 | W 10 | W 20 | W 20 | W 20 | W 20 | W 15 | W 10 |
| Gusts km/h | 40 | 40 | 40 | |||||
| Waves (est.) m | 0.1 | 0.1 | 0.2 | 0.2 | ||||
| Temp. °C | 9 | 8 | 10 | 11 | 10 | 6 | 5 | 2 |
| Precip. % | 60 | 40 | 40 | 40 | 40 | 40 | 0 | 0 |
Tonight: Mainly cloudy with 60 percent chance of showers. Risk of a thunderstorm this evening. Wind west 20 km/h gusting to 40 becoming light this evening. Low 8.
Weather: Thetford Mines (local forecast), as of 4:02 a.m. EDT
Sun and moon
- Civil dawn
- 6:23 a.m.
- Sunrise
- 6:53 a.m.
- Sunset
- 6:09 p.m.
- Civil dusk
- 6:39 p.m.
- Moonrise
- 5:43 a.m.
- Moonset
- 5:27 p.m.
- Moon
- Waning crescent, 1% lit
Follow this lake by email: a weekly summary of conditions.
Depth
29% of Lac Thor is shallower than 3 m, and 54% is deeper than 5 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 records a maximum depth of 10.9 m, drawn from 12 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: oligo-mesotrophic (transition).
Clarity was measured with a Secchi disk in 2 years between 2024 and 2025; the latest annual mean is 4.5 m.
Photos
Follow this lake
Every Friday by email: the Environment Canada forecast and any weather alerts in effect.