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Map of Source Lake

Source Lake

45.562° N, 78.6514° W

Shoreline and neighbouring water from open government data.

Download the map (SVG)

Source Lake, Ontario. 45.562° N, 78.6514° W

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 Depths are from government surveys and may be outdated.

borealbound.ca/lakes/on/source-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.
  • Fishing access points, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
  • 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.
  • 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).

Source Lake covers 2.67 km², making it larger than 85% of the 18,731 lakes in Ontario. It lies 2.9 km west of Algonquin Park.

Area
2.67 km²
larger than 85% of the 18,731 lakes in Ontario
Shoreline
15 km
longer than 83% of the 18,731 lakes in Ontario
Water clarity
5.1 mSecchi depth, 2025
clearer than 81% of the 1,251 monitored lakes in Ontario
Elevation
447 m

Today on the water

4.8 °C

Wind W 4 km/h

Observed at Algonquin Park (Lake of Two Rivers), as of 3:00 a.m. EDT

choppy Estimated waves, next 12 hours: up to 0.2 m. Around 4 a.m., wind from the west: the west shore is sheltered, waves build toward the east shore.

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/hW 15W 15W 15NW 30NW 30NW 15var. 5var. 5
Gusts km/h5050
Waves (est.) m0.20.20.20.20.2
Temp. °C126101294-1
Precip. %40404040202000

Tonight: Partly cloudy with 60 percent chance of showers. Risk of a thunderstorm early this evening. Wind west 30 km/h gusting to 50 becoming light this evening. Low plus 1.

Weather: Algonquin Park (Lake of Two Rivers) (local forecast), as of 3:03 a.m. EDT

Sun and moon

Civil dawn
6:53 a.m.
Sunrise
7:23 a.m.
Sunset
6:39 p.m.
Civil dusk
7:09 p.m.
Moonrise
6:15 a.m.
Moonset
5:58 p.m.
Moon
Waning crescent, 1% lit

Air Quality Health Index

2 low risk

Dorset, as of 3:00 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.

Water

Clarity was measured with a Secchi disk in 19 years between 2001 and 2025; the latest annual mean is 5.1 m.

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

Getting on the water

1 listed boat launch. marks launches on the map.