Mattawa Lake
49.6983° N, 90.9764° W
Shoreline and neighbouring water from open government data.
Download the map (SVG)Mattawa Lake, Ontario. 49.6983° N, 90.9764° W
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/on/mattawa-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.
- 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.
Mattawa Lake covers 17.8 km², making it larger than 97% of the 18,731 lakes in Ontario. It lies 18 km east of Clarkdon.
Government surveys have recorded 14 fish species here, including walleye, yellow perch and cisco.
- Area
- 17.8 km²
- larger than 97% of the 18,731 lakes in Ontario
- Shoreline
- 77 km
- longer than 97% of the 18,731 lakes in Ontario
- Fish species
- 14
- more than 86% of the 2,454 surveyed lakes in Ontario
- Elevation
- 434 m
Today on the water
4 °C
Observed at Ignace, as of 6:00 a.m. CDT
choppy Estimated waves, next 12 hours: up to 0.2 m. Around 7 p.m., wind from the southeast: the southeast shore is sheltered, waves build toward the northwest 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 | var. 5 | var. 5 | SE 10 | SE 10 | SE 20 | SE 20 | SE 20 | SE 20 |
| Gusts km/h | 40 | 40 | 40 | 40 | ||||
| Waves (est.) m | 0.1 | 0.1 | 0.1 | 0.1 | 0.2 | |||
| Temp. °C | 2 | 8 | 12 | 15 | 11 | 11 | 9 | 13 |
| Precip. % | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Today: A mix of sun and cloud. Becoming cloudy this afternoon. High 15. UV index 3 or moderate.
Weather: Ignace (local forecast), as of 6:01 a.m. CDT
Sun and moon
- Civil dawn
- 6:44 a.m.
- Sunrise
- 7:16 a.m.
- Sunset
- 6:25 p.m.
- Civil dusk
- 6:57 p.m.
- Moonrise
- 6:09 a.m.
- Moonset
- 5:44 p.m.
- Moon
- Waning crescent, 1% lit
Fish
Sport fish by the share of the 27 government surveys (2009–2009) that recorded them.
Forage fish and other species (5)
Forage fish
- Emerald Shiner 6
- Spottail Shiner 6
- Trout-Perch 3
Other
- White Sucker 17
- Shorthead Redhorse 4
Numbers are the surveys that recorded each species.
Eating your catch
The provincial guide to eating fish (2026) sets limits for 3 species from Mattawa Lake. Maximum meals per month:
| Species | Length | General population | Sensitive population* | Contaminant |
|---|---|---|---|---|
| Northern Pike | 55-60 cm | 4 | Do not eat | Mercury |
| Smallmouth Bass | 35-40 cm | 8 | Do not eat | Mercury |
| Walleye | 40-45 cm | 4 | Do not eat | 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 4. Check seasons and limits before you fish.