Fraser

Fraser, river in southern British Columbia, Canada. The Fraser rises in the Rocky Mountains, in Mount Robson Provincial Park near the Alberta border, and flows 1,368 km (850 mi) before emptying, through a delta, into the Strait of Georgia, near Vancouver.

The Fraser initially flows north-west through a section of a deep, narrow valley called the Rocky Mountain Trench. It then turns south near the city of Prince George, where it receives its major western tributary, the Nechako River. In its central section, the volume of the river increases, and below Quesnel its banks gradually take on a canyonlike aspect. Important tributaries in this section include the West Road and Chilcotin rivers, from the west, and the Thompson River, from the east. From Lytton to Yale the river is forced into a narrow canyon of great scenic beauty through which it passes at great speed. At the canyon's southern end the Fraser passes between the Cascade Range to the east and the Coast Mountains to the west. A little below Yale, at Hope, the river turns sharply west, and the fertile lower Fraser Valley begins. The Fraser empties into the Strait of Georgia through three main channels. The river is used by commercial vessels for a short distance upstream. From May to July the Fraser Valley is subject to flooding; a series of dykes helps protect the delta.

The Fraser drains an area of about 238,000 sq km (91,890 sq mi). Much of the river basin is heavily wooded, and forest-products industries dominate the economy of the settlements along the river. The lower Fraser Valley, including the delta, has highly productive farms. Various species of salmon spawn in the Fraser, and salmon fisheries are located near the river's mouth. The river has great hydroelectric potential, but it remains undeveloped for fear of detrimental effects on the migratory habits of the salmon. The Fraser is highly polluted, especially at its mouth.

The first European to visit the river was Sir Alexander Mackenzie in 1793. It is named after the fur trader Simon Fraser, who explored the river to its mouth on behalf of the North West Company in 1808. In 1858 gold was found in alluvial gravels north of Yale, and a major gold rush ensued. In the early 1880s the lower reaches of the river, south from Lytton, were chosen for the route of the Canadian Pacific Railway; the ledge for the rail bed was chipped and blasted from the side of the canyon in one of the great feats of 19th-century railway building. In the 20th century the routes of the Canadian National Railway and the Trans-Canada Highway were also built along this stretch of the river.