Saguenay River

The Saguenay River (French: rivière Saguenay) is a major river of Quebec, Canada. It drains Lac Saint-Jean in the Laurentian Highlands, leaving at Alma and running east, and passes the city of Saguenay. It drains into the Saint Lawrence River at Tadoussac.

The river has a very high flow-rate and is bordered by steep cliffs associated with the Saguenay Graben. Tide waters flow in its fjord upriver as far as Chicoutimi (about 100 kilometres). Many Beluga whales breed in the cold waters at its mouth, making Tadoussac a popular site for whale watching and sea kayaking; Greenland sharks also frequent the depths of the river. The confluence of the Saguenay and Saint Lawrence is protected by the Saguenay–St. Lawrence Marine Park, one of Canada's national parks.

The Saguenay River offered an important trade route into the interior for the First Nations people of the area. During the French colonization of the Americas, the river became a major route for the fur trade. The French established Tadoussac, France's first trading post in Canada, in 1600. The river takes its name from the legendary Kingdom of Saguenay. It is the namesake of Saguenay Herald at the Canadian Heraldic Authority.

Beginning in the 19th century, the river was used the logging and pulp and paper industries. It generates hydroelectricity, both for commercial power and to operate an aluminum smelter at Arvida.

Severe flooding of the Saguenay's tributary rivers from July 18 to 21, 1996, devastated the region in one of Canada's costliest natural disasters, the Saguenay Flood. However, an unexpected effect of the same flooding was to cover the heavily contaminated sediments at the bottom of the river with 10 to 50 centimetres (3.9 to 20 in) of new, relatively clean sediments. Research has shown that the old sediments are no longer a threat to ecosystems.