Basswood Lake
46.3331° N, 83.3966° W
Depth contours from the 1965 government survey. Not for navigation.
Download the depth map (SVG)Basswood Lake, Ontario. 46.3331° N, 83.3966° W
Maximum depth 73.2 m (1965 survey). Scale bar on the map.
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/on/basswood-lake-near-thessalon/, 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.
- Aquatic Resource Area survey points, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
- 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).
- Guide to Eating Ontario Fish: Advisory Database, Ontario Ministry of the Environment, Conservation and Parks. Contains information licensed under the Open Government Licence – Ontario.
Basswood Lake is 73.2 m deep at its deepest point, deeper than 97% of the 2,688 surveyed lakes in Ontario. It covers 27 km² and lies beside Day Mills.
Government surveys have recorded 13 fish species here, including lake whitefish, lake trout and burbot.
- Maximum depth
- 73.2 msurveyed 1965
- deeper than 97% of the 2,688 surveyed lakes in Ontario
- Area
- 27 km²
- larger than 98% of the 18,731 lakes in Ontario
- Shoreline
- 46.6 km
- longer than 95% of the 18,731 lakes in Ontario
- Water clarity
- 11.1 mSecchi depth, 2025
- clearer than 99% of the 1,251 monitored lakes in Ontario
- Fish species
- 13
- more than 84% of the 2,454 surveyed lakes in Ontario
- Elevation
- 206 m
Today on the water
10.8 °C
Observed at Blind River, as of 6:00 a.m. EDT
choppy Estimated waves, next 12 hours: up to 0.3 m. Around 10 a.m., wind from the northwest: the northwest shore is sheltered, waves build toward the southeast shore.
| Time | 7 a.m. | 10 a.m. | 1 p.m. | 4 p.m. | 7 p.m. | 10 p.m. | 1 a.m. | 4 a.m. |
|---|---|---|---|---|---|---|---|---|
| Wind km/h | W 10 | NW 20 | NW 20 | NW 20 | var. 5 | var. 5 | E 10 | E 10 |
| Gusts km/h | 40 | 40 | 40 | |||||
| Waves (est.) m | 0.2 | 0.3 | 0.3 | 0.3 | ||||
| Temp. °C | 7 | 8 | 11 | 13 | 13 | 9 | 6 | 5 |
| Precip. % | 30 | 20 | 20 | 0 | 0 | 0 | 0 | 0 |
Today: A mix of sun and cloud. 30 percent chance of showers early this morning. Clearing this afternoon. Wind becoming northwest 20 km/h gusting to 40 this morning. High 14. UV index 4 or moderate.
Weather: Blind River (local forecast), as of 6:01 a.m. EDT
Sun and moon
- Civil dawn
- 7:12 a.m.
- Sunrise
- 7:42 a.m.
- Sunset
- 6:57 p.m.
- Civil dusk
- 7:28 p.m.
- Moonrise
- 6:35 a.m.
- Moonset
- 6:16 p.m.
- Moon
- Waning crescent, 1% lit
Follow this lake by email: a weekly summary of conditions.
Depth
7% of Basswood Lake is shallower than 3 m, and 61% is deeper than 30 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 1965 records a maximum depth of 73.2 m, drawn from 35 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.
Fish
Sport fish by the share of the 69 government surveys (2008–2013) that recorded them.
Forage fish and other species (7)
Forage fish
- Lake Chub 20
- Rainbow Smelt 9
- Slimy Sculpin 2
- Spoonhead Sculpin 1
Other
- White Sucker 23
- Brown Bullhead 3
- Longnose Sucker 1
Numbers are the surveys that recorded each species.
Eating your catch
The provincial guide to eating fish (2026) sets limits for 2 species from Basswood Lake. Maximum meals per month:
| Species | Length | General population | Sensitive population* | Contaminant |
|---|---|---|---|---|
| Lake Trout | 50-55 cm | 8 | 8 | PCB |
| Smallmouth Bass | 35-40 cm | 16 | 8 | Mercury, PCB |
* As defined in the guide, including children and people who are or may become pregnant. Limits are for the length the guide lists most often; they change with the size of the fish. Read the official guide
Fishing regulations: Fisheries Management Zone 10. Check seasons and limits before you fish.
Water
Clarity was measured with a Secchi disk in 23 years between 1999 and 2025; the latest annual mean is 11.1 m.
Getting on the water
1 listed boat launch; 1 with parking listed. marks launches on the map.
- Basswood Lake Boat Launch
Follow this lake
Every Friday by email: the Environment Canada forecast and any weather alerts in effect.