Lac Blanc
46.821° N, 72.2748° W
Depth contours from the 2012 government survey. Not for navigation.
Download the depth map (SVG)Lac Blanc, Quebec. 46.821° N, 72.2748° W
Maximum depth 42.1 m (2012 survey). Scale bar on the map.
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/qc/lac-blanc-near-saint-marc-des-carrieres/, 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.
- Real-time hydrometric data, Environment and Climate Change Canada. Contains data from Environment and Climate Change Canada (ECCC Data Servers End-use Licence).
- National Water Data Archive (HYDAT) daily means, Environment and Climate Change Canada. Contains data from Environment and Climate Change Canada (ECCC Data Servers End-use Licence).
- 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 Blanc is 42.1 m deep at its deepest point, deeper than 91% of the 1,506 surveyed lakes in Quebec. It covers 2.05 km² and lies beside Lac-Blanc.
- Maximum depth
- 42.1 msurveyed 2012
- deeper than 91% of the 1,506 surveyed lakes in Quebec
- Area
- 2.05 km²
- larger than 83% of the 29,407 lakes in Quebec
- Shoreline
- 13.4 km
- longer than 83% of the 29,407 lakes in Quebec
- Water clarity
- 2.8 mSecchi depth, 2025
- less clear than 71% of the 805 monitored lakes in Quebec
- Elevation
- 140 m
Today on the water
YELLOW ADVISORY - FROST · issued 4:39 a.m. EDT
Temperatures will drop to near the freezing mark overnight tonight. Take preventative measures to protect cold-sensitive plants, trees, and crops. Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to QCstorm@ec.gc.ca or post reports on social media using #QCStorm.
Official alert on weather.gc.ca · expires 8:39 p.m. EDT
4.5 °C
Observed at Donnacona, as of 6:00 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 | 7 a.m. | 10 a.m. | 1 p.m. | 4 p.m. | 7 p.m. | 10 p.m. | 1 a.m. | 4 a.m. |
|---|---|---|---|---|---|---|---|---|
| Wind km/h | W 15 | W 20 | W 20 | W 20 | W 20 | W 20 | W 20 | W 20 |
| Gusts km/h | 40 | 40 | 40 | 40 | ||||
| Waves (est.) m | 0.1 | 0.2 | 0.2 | 0.2 | ||||
| Temp. °C | 7 | 9 | 10 | 10 | 7 | 4 | 1 | 2 |
| Precip. % | 30 | 30 | 30 | 30 | 0 | 0 | 0 | 0 |
Today: A mix of sun and cloud with 30 percent chance of showers. Wind becoming west 20 km/h gusting to 40 this morning. High 11. UV index 3 or moderate.
Weather: Donnacona (local forecast), as of 6:02 a.m. EDT
Sun and moon
- Civil dawn
- 6:28 a.m.
- Sunrise
- 6:58 a.m.
- Sunset
- 6:13 p.m.
- Civil dusk
- 6:43 p.m.
- Moonrise
- 5:48 a.m.
- Moonset
- 5:31 p.m.
- Moon
- Waning crescent, 1% lit
Follow this lake by email: a weekly summary of conditions.
Depth
29% of Lac Blanc is deeper than 20 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 2012 records a maximum depth of 42.1 m, drawn from 15 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: mesotrophic.
Clarity was measured with a Secchi disk in 19 years between 2007 and 2025; the latest annual mean is 2.8 m.
Follow this lake
Every Friday by email: the Environment Canada forecast, the water level at the nearest gauge and any weather alerts in effect.