O.S.A. Lake
46.0551° N, 81.4009° W
Depth contours from the government survey. Not for navigation.
Download the depth map (SVG)O.S.A. Lake, Ontario. 46.0551° N, 81.4009° W
Maximum depth 36.6 m. Scale bar on the map.
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/on/o-s-a-lake/, 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.
- Fisheries Management Zones, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
- Lake Partner Program, Ontario Ministry of the Environment, Conservation and Parks. Contains information licensed under the Open Government Licence – Ontario.
- Bathymetry lines and survey index, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
- 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).
- Air Quality Health Index observations and forecasts, Environment and Climate Change Canada. Contains data from Environment and Climate Change Canada (ECCC Data Servers End-use Licence).
O.S.A. Lake is 36.6 m deep at its deepest point, deeper than 85% of the 2,688 surveyed lakes in Ontario. It covers 2.93 km² and lies 12 km northeast of Killarney.
- Maximum depth
- 36.6 m
- deeper than 85% of the 2,688 surveyed lakes in Ontario
- Area
- 2.93 km²
- larger than 86% of the 18,731 lakes in Ontario
- Shoreline
- 13.6 km
- longer than 81% of the 18,731 lakes in Ontario
- Water clarity
- 13 mSecchi depth, 2004
- clearer than 99% of the 1,251 monitored lakes in Ontario
- Elevation
- 206 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.
| Time | 6 a.m. | 9 a.m. | 12 p.m. | 3 p.m. | 6 p.m. | 9 p.m. | 12 a.m. | 3 a.m. |
|---|---|---|---|---|---|---|---|---|
| Wind km/h | NW 15 | NW 20 | NW 30 | NW 20 | var. 5 | var. 5 | E 10 | SE 10 |
| Gusts km/h | 50 | |||||||
| Waves (est.) m | 0.2 | 0.2 | 0.3 | 0.2 | 0.1 | |||
| Temp. °C | 7 | 8 | 12 | 15 | 15 | 13 | 9 | 5 |
| Precip. % | 30 | 30 | 20 | 20 | 0 | 0 | 0 | 0 |
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 5:05 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 4:00 a.m. EDT
Follow this lake by email: a weekly summary of conditions.
Depth
18% of O.S.A. Lake is shallower than 3 m, and 17% 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 36.6 m, drawn from 38 depth contours.
- Download the depth map (SVG)Printing this page gives the map on one sheet, with scale and sources.
Not for navigation. Depths are from government surveys and may be outdated.
Follow this lake
Every Friday by email: the Environment Canada forecast and any weather alerts in effect.