Koshlong Lake
44.9732° N, 78.4854° W
Shoreline and neighbouring water from open government data.
Download the map (SVG)Koshlong Lake, Ontario. 44.9732° N, 78.4854° W
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/on/koshlong-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.
- 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).
- Guide to Eating Ontario Fish: Advisory Database, Ontario Ministry of the Environment, Conservation and Parks. Contains information licensed under the Open Government Licence – Ontario.
- Photographs, Wikimedia Commons contributors. Each photo carries its own licence (CC0, public domain, CC BY or CC BY-SA), credited where shown.
Koshlong Lake covers 3.78 km², making it larger than 89% of the 18,731 lakes in Ontario. It lies 1.6 km east of Donald.
- Area
- 3.78 km²
- larger than 89% of the 18,731 lakes in Ontario
- Shoreline
- 29.5 km
- longer than 92% of the 18,731 lakes in Ontario
- Water clarity
- 3.9 mSecchi depth, 2025
- clearer than 59% of the 1,251 monitored lakes in Ontario
- Elevation
- 347 m
Today on the water
5.5 °C
Observed at Haliburton, as of 4:00 a.m. EDT
choppy Estimated waves, next 12 hours: up to 0.3 m. Around 12 p.m., wind from the northwest: the northwest shore is sheltered, waves build toward the southeast shore.
| Time | 5 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/h | W 15 | W 15 | W 15 | NW 30 | NW 30 | NW 15 | var. 5 | var. 5 |
| Gusts km/h | 50 | 50 | ||||||
| Waves (est.) m | 0.2 | 0.2 | 0.2 | 0.3 | ||||
| Temp. °C | 3 | 5 | 9 | 12 | 13 | 8 | 3 | 0 |
| Precip. % | 20 | 40 | 40 | 20 | 20 | 0 | 0 | 0 |
Tonight: Partly cloudy. 60 percent chance of showers this evening. Risk of a thunderstorm early this evening. Wind west 30 km/h gusting to 50 becoming light this evening. Low plus 3.
Weather: Haliburton (local forecast), as of 4:02 a.m. EDT
Sun and moon
- Civil dawn
- 6:52 a.m.
- Sunrise
- 7:22 a.m.
- Sunset
- 6:39 p.m.
- Civil dusk
- 7:08 p.m.
- Moonrise
- 6:14 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
Follow this lake by email: a weekly summary of conditions.
Water
Clarity was measured with a Secchi disk in 17 years between 1992 and 2025; the latest annual mean is 3.9 m.
Getting on the water
2 listed boat launches; 1 with parking listed. marks launches on the map.
East shore
- Koshlong Lake, South
Northwest shore
- Koshlong Lake North
Follow this lake
Every Friday by email: the Environment Canada forecast and any weather alerts in effect.