South Nation River
The South Nation River is a river whose watershed covers 3,900 km², a large part of eastern Ontario. The river's headwaters are located north of Brockville, Ontario and it flows 175 km northeast to empty into the Ottawa River near Plantagenet, Ontario.This river is called the "South Nation River" to distinguish it from a river in Quebec north of the Ottawa River called the Petit-Nation River.
The area surrounding the river, originally covered with white pine, is now mainly used for agriculture. Dams and other water control measures have been introduced to help reduce the impact of seasonal flooding in the watershed.
On June 20 1993, a major landslide occurred near the former site of the town of Lemieux, Ontario. Approximately 3 million m³ of mud and clay slid into the river valley, blocking the river's flow for three days.
Tributaries include the
- various branches of the Castor River
- Payne River
- Scotch River
- Bear Brook
- Casselman, Ontario
- Crysler, Ontario
- Plantagenet, Ontario