Map of Lac Aylmer with depth contours

Lac Aylmer

45.9117° N, 71.3708° W

Depth contours from the 2009 government survey. Not for navigation.

Download the depth map (SVG)

Lac Aylmer is 34.1 m deep at its deepest point, deeper than 86% of the 1,506 surveyed lakes in Quebec. It covers 32 km² and lies beside Disraeli.

Maximum depth
34.1 msurveyed 2009
deeper than 86% of the 1,506 surveyed lakes in Quebec
Area
32 km²
larger than 98% of the 29,407 lakes in Quebec
Shoreline
80.6 km
longer than 97% of the 29,407 lakes in Quebec
Water clarity
1.8 mSecchi depth, 2025
less clear than 89% of the 805 monitored lakes in Quebec
Elevation
244 m

Today on the water

6.4 °C

Wind W 7 km/h, gusts 28

Observed at Thetford Mines, as of 1:00 a.m. EDT

choppy Estimated waves, next 12 hours: up to 0.3 m.

Hourly forecast, next 24 hours
Time2 a.m.5 a.m.8 a.m.11 a.m.2 p.m.5 p.m.8 p.m.11 p.m.
Wind km/hW 10W 10W 10W 20W 20W 20W 20W 15
Gusts404040
Waves (est.) m0.10.10.10.30.3
Temp. °C99810111065
Precip. %606040404040400

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 1:02 a.m. EDT

Sun and moon

Civil dawn
6:24 a.m.
Sunrise
6:54 a.m.
Sunset
6:10 p.m.
Civil dusk
6:40 p.m.
Moonrise
5:44 a.m.
Moonset
5:28 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

7% of Lac Aylmer 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 2009 records a maximum depth of 34.1 m, drawn from 52 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 Depths are from government surveys and may be outdated.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 20 years between 2005 and 2025; the latest annual mean is 1.8 m.

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

Photos

Quai de Beaulac-Garthby, lac Aylmer, Qc - panoramio
Photo: busand2003, CC BY 3.0, via Wikimedia Commons
Quai de la marina de Beaulac-Garthby, lac Aylmer, Qc - panoramio
Photo: busand2003, CC BY 3.0, via Wikimedia Commons