Big Rideau Lake
| Big Rideau Lake | |
|---|---|
Sunset on the lake | |
| Location | Lanark County, United Counties of Leeds and Grenville, Ontario |
| Coordinates | 44°45′05″N 76°12′50″W / 44.75139°N 76.21389°W |
| Part of | Saint Lawrence River drainage basin |
| Primary inflows | Black Creek, Rideau River |
| Primary outflows | Rideau River |
| Catchment area | 407 square kilometres (157 sq mi) |
| Basin countries | Canada |
| Max. length | 32 kilometres (20 mi) |
| Max. width | 6 kilometres (3.7 mi) |
| Max. depth | 360 feet (110 m) |
| Surface elevation | 123.1 metres (403 ft 10 in) |
| Settlements | Portland, Rideau Ferry |
Big Rideau Lake is a lake in the municipalities of Tay Valley and Drummond/North Elmsley, Lanark County and Rideau Lakes, United Counties of Leeds and Grenville in Eastern Ontario, Canada. The lake is on the border between the two counties, 72 kilometres (45 mi) to the southwest of Ottawa. It is 32 kilometres (20 mi) long and is 6 kilometres (3.7 mi) wide, is much narrower at its northeastern end than at its southwestern end, and is part of the Saint Lawrence River drainage basin. It is the largest lake on the Rideau Canal, which was designated a UNESCO world heritage site in 2007.