Twelve Mile Lake
45.0253° N, 78.7058° W
Depth contours from the government survey. Not for navigation.
Download the depth map (SVG)Twelve Mile Lake, Ontario. 45.0253° N, 78.7058° W
Maximum depth 27.4 m. Scale bar on the map.
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/on/twelve-mile-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).
- 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.
- Ontario Waterbody Location Identifier, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
Twelve Mile Lake is 27.4 m deep at its deepest point, deeper than 74% of the 2,688 surveyed lakes in Ontario. It covers 3.65 km² and lies beside Carnarvon.
Government surveys have recorded 16 fish species here, including yellow perch, rock bass and smallmouth bass.
- Maximum depth
- 27.4 m
- deeper than 74% of the 2,688 surveyed lakes in Ontario
- Area
- 3.65 km²
- larger than 89% of the 18,731 lakes in Ontario
- Shoreline
- 13 km
- longer than 80% of the 18,731 lakes in Ontario
- Water clarity
- 5.6 mSecchi depth, 2016
- clearer than 86% of the 1,251 monitored lakes in Ontario
- Fish species
- 16
- more than 91% of the 2,454 surveyed lakes in Ontario
- Elevation
- 304 m
Today on the water
4.1 °C
Observed at Oxtongue Lake, as of 7:00 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 | 8 a.m. | 11 a.m. | 2 p.m. | 5 p.m. | 8 p.m. | 11 p.m. | 2 a.m. | 5 a.m. |
|---|---|---|---|---|---|---|---|---|
| Wind km/h | W 15 | W 15 | NW 30 | NW 30 | NW 15 | var. 5 | var. 5 | SE 10 |
| Gusts km/h | 50 | 50 | ||||||
| Waves (est.) m | 0.1 | 0.1 | 0.3 | 0.3 | 0.2 | |||
| Temp. °C | 4 | 8 | 12 | 13 | 8 | 2 | -2 | -3 |
| Precip. % | 40 | 40 | 20 | 20 | 0 | 0 | 0 | 0 |
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 13. UV index 4 or moderate.
Weather: Oxtongue Lake (local forecast), as of 7:03 a.m. EDT
Sun and moon
- Civil dawn
- 6:53 a.m.
- Sunrise
- 7:22 a.m.
- Sunset
- 6:40 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
1 low risk
Dorset, as of 7:00 a.m. EDT
Depth
57% of Twelve Mile 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 records a maximum depth of 27.4 m, drawn from 16 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 44 government surveys (2011–2015) that recorded them.
Forage fish and other species (6)
Forage fish
- Rainbow Smelt 7
- Bluntnose Minnow 4
- Slimy Sculpin 2
- Spottail Shiner 1
Other
- White Sucker 6
- Brown Bullhead 1
Numbers are the surveys that recorded each species.
Eating your catch
The provincial guide to eating fish (2026) sets limits for 7 species from Twelve Mile Lake. Maximum meals per month:
| Species | Length | General population | Sensitive population* | Contaminant |
|---|---|---|---|---|
| Lake Trout | 50-55 cm | 12 | 4 | Mercury |
| Lake Whitefish | 45-50 cm | 16 | 4 | Mercury |
| Northern Pike | 60-65 cm | 16 | 4 | Mercury |
| Rock Bass | 15-20 cm | 16 | 8 | Mercury |
| Smallmouth Bass | 35-40 cm | 12 | 4 | Mercury |
| Walleye | 40-45 cm | 16 | 4 | Mercury |
| Cisco (Lake Herring) | 20-25 cm | 16 | 8 | 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.
Water
Clarity was measured with a Secchi disk in 16 years between 1992 and 2016; the latest annual mean is 5.6 m.