Constant Lake
45.4035° N, 76.9847° W
Depth contours from the 1960 government survey. Not for navigation.
Download the depth map (SVG)Constant Lake, Ontario. 45.4035° N, 76.9847° W
Maximum depth 18.3 m (1960 survey). Scale bar on the map.
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/on/constant-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.
- Aquatic Resource Area survey 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.
Constant Lake is 18.3 m deep at its deepest point, deeper than 54% of the 2,688 surveyed lakes in Ontario. It covers 5.61 km² and lies beside Balaclava.
Government surveys have recorded 5 fish species here, including pumpkinseed, smallmouth bass and largemouth bass.
- Maximum depth
- 18.3 msurveyed 1960
- deeper than 54% of the 2,688 surveyed lakes in Ontario
- Area
- 5.61 km²
- larger than 92% of the 18,731 lakes in Ontario
- Shoreline
- 40.4 km
- longer than 94% of the 18,731 lakes in Ontario
- Fish species
- 5
- more than 53% of the 2,454 surveyed lakes in Ontario
- Elevation
- 192 m
Today on the water
10.9 °C
Observed at Renfrew, as of 9:47 p.m. EDT Thursday
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 | 4 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/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 | 4 | 8 | 11 | 13 | 10 | 5 | 2 |
| Precip. % | 40 | 40 | 40 | 40 | 20 | 20 | 0 | 0 |
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 3.
Weather: Renfrew (local forecast), as of 3:05 a.m. EDT
Sun and moon
- Civil dawn
- 6:46 a.m.
- Sunrise
- 7:16 a.m.
- Sunset
- 6:33 p.m.
- Civil dusk
- 7:02 p.m.
- Moonrise
- 6:07 a.m.
- Moonset
- 5:51 p.m.
- Moon
- Waning crescent, 1% lit
Follow this lake by email: a weekly summary of conditions.
Depth
23% of Constant Lake is deeper than 10 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 1960 records a maximum depth of 18.3 m, drawn from 10 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 4 government surveys (2012–2012) that recorded them.
Eating your catch
The provincial guide to eating fish (2026) sets limits for 4 species from Constant Lake. Maximum meals per month:
| Species | Length | General population | Sensitive population* | Contaminant |
|---|---|---|---|---|
| Northern Pike | 55-60 cm | 12 | 4 | Mercury |
| Smallmouth Bass | 35-40 cm | 8 | Do not eat | Mercury |
| Walleye | 40-45 cm | 8 | 4 | Mercury |
| Yellow Perch | 20-25 cm | 12 | 4 | Mercury |
* 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 15. Check seasons and limits before you fish.
Follow this lake
Every Friday by email: the Environment Canada forecast and any weather alerts in effect.