Map of Threenarrows Lake with depth contours

Threenarrows Lake

46.0994° N, 81.4333° W

Depth contours from the government survey. Not for navigation.

Download the depth map (SVG)

Threenarrows Lake is 48.8 m deep at its deepest point, deeper than 93% of the 2,688 surveyed lakes in Ontario. It covers 8.79 km² and lies 11 km north of Killarney.

Maximum depth
48.8 m
deeper than 93% of the 2,688 surveyed lakes in Ontario
Area
8.79 km²
larger than 95% of the 18,731 lakes in Ontario
Shoreline
92 km
longer than 98% of the 18,731 lakes in Ontario
Elevation
193 m

Today on the water

choppy Estimated waves, next 12 hours: up to 0.3 m. Around 11 a.m., wind from the northwest: the northwest shore is sheltered, waves build toward the southeast shore.

Hourly forecast, next 24 hours
Time4 a.m.7 a.m.10 a.m.1 p.m.4 p.m.7 p.m.10 p.m.1 a.m.
Wind km/hNW 20NW 15NW 20NW 30NW 20var. 5var. 5E 10
Gusts km/h50
Waves (est.) m0.20.10.20.3
Temp. °C7710131515126
Precip. %3030302020000

Tonight: Partly cloudy with 30 percent chance of showers. Wind west 40 km/h gusting to 60 becoming northwest 20 gusting to 40 early this evening. Low 7.

Weather: Killarney (local forecast), as of 3:05 a.m. EDT

Sun and moon

Civil dawn
7:04 a.m.
Sunrise
7:34 a.m.
Sunset
6:50 p.m.
Civil dusk
7:20 p.m.
Moonrise
6:26 a.m.
Moonset
6:08 p.m.
Moon
Waning crescent, 1% lit

Air Quality Health Index

1 low risk

Sudbury, as of 2:00 a.m. EDT

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

26% of Threenarrows Lake 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 records a maximum depth of 48.8 m, drawn from 67 depth contours.

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 Depths are from government surveys and may be outdated.