Map of Lac Saint-Augustin with depth contours

Lac Saint-Augustin

46.75° N, 71.3925° W

Depth contours from the 1975 government survey. Not for navigation.

Download the depth map (SVG)

Lac Saint-Augustin is 6.1 m deep at its deepest point, shallower than 89% of the 1,506 surveyed lakes in Quebec. It covers 0.68 km² and lies 4.5 km northeast of Saint-Augustin-de-Desmaures.

Maximum depth
6.1 msurveyed 1975
shallower than 89% of the 1,506 surveyed lakes in Quebec
Area
0.68 km²
larger than 68% of the 29,407 lakes in Quebec
Shoreline
5.2 km
longer than 62% of the 29,407 lakes in Quebec
Water clarity
1 mSecchi depth, 2025
less clear than 98% of the 805 monitored lakes in Quebec
Elevation
40 m

Today on the water

6.7 °C

Wind SSW 7 km/h

Observed at Bernières, as of 4:00 a.m. EDT

calm Estimated waves, next 12 hours: up to 0.1 m. Around 5 a.m., wind from the west: the west shore is sheltered, waves build toward the east shore.

Hourly forecast, next 24 hours
Time5 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/hW 15W 15W 20W 20W 20W 20W 20W 20
Gusts km/h404040
Waves (est.) m0.10.10.10.10.1
Temp. °C668139633
Precip. %4030303030000

Tonight: A few showers ending early this evening then partly cloudy with 40 percent chance of showers. Risk of a thunderstorm early this evening. Wind southwest 20 km/h gusting to 40 becoming light this evening. Low plus 5.

Weather: Bernières (local forecast), as of 4:02 a.m. EDT

Sun and moon

Civil dawn
6:24 a.m.
Sunrise
6:55 a.m.
Sunset
6:09 p.m.
Civil dusk
6:39 p.m.
Moonrise
5:45 a.m.
Moonset
5:27 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

29% of Lac Saint-Augustin is shallower than 3 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 1975 records a maximum depth of 6.1 m, drawn from 9 depth contours.

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 Depths are from government surveys and may be outdated.

Water

Trophic status from the latest monitoring: eutrophic.

Clarity was measured with a Secchi disk in 2 years between 2005 and 2025; the latest annual mean is 1 m.

Water clarity (Secchi depth, m)