Map of Lac Osisko with depth contours

Lac Osisko

48.2553° N, 78.9838° W

Depth contours from the 1978 government survey. Not for navigation.

Download the depth map (SVG)

Lac Osisko is 7.8 m deep at its deepest point, shallower than 83% of the 1,506 surveyed lakes in Quebec. It covers 3.87 km² and lies beside Rouyn-Noranda.

Maximum depth
7.8 msurveyed 1978
shallower than 83% of the 1,506 surveyed lakes in Quebec
Area
3.87 km²
larger than 89% of the 29,407 lakes in Quebec
Shoreline
19.8 km
longer than 88% of the 29,407 lakes in Quebec
Water clarity
3.7 mSecchi depth, 2025
less clear than 52% of the 805 monitored lakes in Quebec
Elevation
288 m

Today on the water

3.8 °C

Mostly CloudyWind N 9 km/h

Observed at Rouyn-Noranda, as of 7:00 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.

Hourly forecast, next 24 hours
Time8 a.m.11 a.m.2 p.m.5 p.m.8 p.m.11 p.m.2 a.m.5 a.m.
Wind km/hW 15W 20NW 20NW 20W 10W 10var. 5var. 5
Gusts km/h404040
Waves (est.) m0.10.20.20.20.1
Temp. °C347843-1-2
Precip. %30303000000

Today: A mix of sun and cloud with 30 percent chance of rain showers or flurries. Wind becoming northwest 20 km/h gusting to 40 this morning. High 8. UV index 3 or moderate.

Weather: Rouyn-Noranda (local forecast), as of 7:02 a.m. EDT

Sun and moon

Civil dawn
6:55 a.m.
Sunrise
7:26 a.m.
Sunset
6:38 p.m.
Civil dusk
7:09 p.m.
Moonrise
6:17 a.m.
Moonset
5:57 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

The government depth survey from 1978 records a maximum depth of 7.8 m, drawn from 20 depth contours.

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 Depths are from government surveys and may be outdated.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 6 years between 2018 and 2025; the latest annual mean is 3.7 m.

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

Photos

Fountain on Osisko Lake
Photo: Mathieu Pelletier, Public domain, via Wikimedia Commons
Les cygnes du lac Osisko
Photo: Maé-soleil veillette, CC BY 4.0, via Wikimedia Commons
Osisko lake
Photo: Ptijue, CC BY-SA 4.0, via Wikimedia Commons