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Map of Knowlton Lake with depth contours

Knowlton Lake

44.4562° N, 76.6128° W

Depth contours from the 1958 government survey. Not for navigation.

Download the depth map (SVG)

Knowlton Lake, Ontario. 44.4562° N, 76.6128° W

Maximum depth 34.7 m (1958 survey). Scale bar on the map.

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 Depths are from government surveys and may be outdated.

borealbound.ca/lakes/on/knowlton-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.

Knowlton Lake is 34.7 m deep at its deepest point, deeper than 85% of the 2,688 surveyed lakes in Ontario. It covers 1.96 km² and lies beside Holleford.

Maximum depth
34.7 msurveyed 1958
deeper than 85% of the 2,688 surveyed lakes in Ontario
Area
1.96 km²
larger than 80% of the 18,731 lakes in Ontario
Shoreline
11.7 km
longer than 77% of the 18,731 lakes in Ontario
Water clarity
6.3 mSecchi depth, 2024
clearer than 92% of the 1,251 monitored lakes in Ontario
Elevation
138 m

Today on the water

11.7 °C

Mostly CloudyWind NW 15 km/h

Observed at Sydenham, as of 10:00 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.

Time11 a.m.2 p.m.5 p.m.8 p.m.11 p.m.2 a.m.5 a.m.8 a.m.
Wind km/hW 15NW 30NW 30NW 15var. 5var. 5var. 5var. 5
Gusts km/h5050
Waves (est.) m0.10.30.30.1
Temp. °C111415105101
Precip. %404020200000

Today: A mix of sun and cloud. 40 percent chance of showers this morning and early this afternoon. Wind becoming northwest 30 km/h gusting to 50 near noon. High 15. UV index 4 or moderate.

Weather: Sydenham (local forecast), as of 10:02 a.m. EDT

Sun and moon

Civil dawn
6:45 a.m.
Sunrise
7:14 a.m.
Sunset
6:32 p.m.
Civil dusk
7:01 p.m.
Moonrise
6:06 a.m.
Moonset
5:50 p.m.
Moon
Waning crescent, 1% lit

Air Quality Health Index

1 low risk

Kingston, as of 9:00 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.

Depth

36% of Knowlton Lake 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 from 1958 records a maximum depth of 34.7 m, drawn from 15 depth contours.

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 Depths are from government surveys and may be outdated.

Water

Clarity was measured with a Secchi disk in 6 years between 2000 and 2024; the latest annual mean is 6.3 m.

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

Getting on the water

1 listed boat launch. marks launches on the map.