Lower Rideau Lake
44.8661° N, 76.1189° W
Shoreline and neighbouring water from open government data.
Download the map (SVG)Lower Rideau Lake, Ontario. 44.8661° N, 76.1189° W
Not for navigation. Depths are from government surveys and may be outdated.
borealbound.ca/lakes/on/lower-rideau-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.
- 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.
- Ontario Waterbody Location Identifier, Ontario Ministry of Natural Resources. Contains information licensed under the Open Government Licence – Ontario.
Lower Rideau Lake covers 12.6 km², making it larger than 96% of the 18,731 lakes in Ontario. It lies beside Beveridge Locks.
Government surveys have recorded 6 fish species here, including largemouth bass, smallmouth bass and northern pike.
- Area
- 12.6 km²
- larger than 96% of the 18,731 lakes in Ontario
- Shoreline
- 44.5 km
- longer than 95% of the 18,731 lakes in Ontario
- Water clarity
- 2.6 mSecchi depth, 2014
- less clear than 71% of the 1,251 monitored lakes in Ontario
- Fish species
- 6
- more than 57% of the 2,454 surveyed lakes in Ontario
- Elevation
- 122 m
Today on the water
7.5 °C
Observed at Smiths Falls, as of 3:00 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 | 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 | NW 10 | NW 10 |
| Gusts km/h | 50 | 50 | ||||||
| Waves (est.) m | 0.2 | 0.2 | 0.2 | 0.3 | ||||
| Temp. °C | 4 | 5 | 9 | 12 | 14 | 10 | 5 | 3 |
| Precip. % | 20 | 40 | 40 | 40 | 40 | 20 | 20 | 0 |
Tonight: Partly cloudy. 60 percent chance of showers this evening. Risk of a thunderstorm early this evening. Wind west 30 km/h gusting to 50 becoming light this evening. Low plus 4.
Weather: Smiths Falls (local forecast), as of 3:03 a.m. EDT
Sun and moon
- Civil dawn
- 6:43 a.m.
- Sunrise
- 7:12 a.m.
- Sunset
- 6:30 p.m.
- Civil dusk
- 6:59 p.m.
- Moonrise
- 6:04 a.m.
- Moonset
- 5:48 p.m.
- Moon
- Waning crescent, 1% lit
Follow this lake by email: a weekly summary of conditions.
Fish
Sport fish by the share of the 13 government surveys (2018–2019) that recorded them.
Eating your catch
The provincial guide to eating fish (2026) sets limits for 8 species from Lower Rideau Lake. Maximum meals per month:
| Species | Length | General population | Sensitive population* | Contaminant |
|---|---|---|---|---|
| Lake Trout | 50-55 cm | 8 | 4 | Mercury |
| Largemouth Bass | 30-35 cm | 8 | 4 | Mercury |
| Northern Pike | 55-60 cm | 8 | Do not eat | Mercury |
| Pumpkinseed | 15-20 cm | 16 | 8 | Mercury |
| Rock Bass | 15-20 cm | 16 | 4 | Mercury |
| Walleye | 60-65 cm | 4 | Do not eat | Mercury |
| Yellow Perch | 20-25 cm | 16 | 4 | Mercury |
| Brown Bullhead | 25-30 cm | 16 | 16 | Precautionary |
* 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 18. Check seasons and limits before you fish.
Water
Clarity was measured with a Secchi disk in 7 years between 1996 and 2014; the latest annual mean is 2.6 m.
Getting on the water
2 listed access points, one of them a boat launch. marks launches on the map.
- Boat launch
- Shore access
Follow this lake
Every Friday by email: the Environment Canada forecast and any weather alerts in effect.