Columbia River

Columbia River
source
Name	Columbia River
Caption	The Columbia River Gorge looking eastward
Source1 location	Columbia Lake, British Columbia
Mouth location	Pacific Ocean at Clatsop County, Oregon and Pacific County, Washington
Length	1243 mi
Discharge1 avg	265000 cuft/s
Basin size	258000 sqmi

Columbia River. The Columbia River is the largest river in the Pacific Northwest region of North America, flowing from the Canadian Rockies in British Columbia through the U.S. state of Washington and forming much of the border with Oregon before emptying into the Pacific Ocean. Its massive drainage basin, known as the Columbia Basin, extends into seven U.S. states and one Canadian province, encompassing diverse ecosystems from alpine forests to arid plateaus. The river's tremendous flow and elevation drop have made it a paramount source of hydropower, irrigation, and transportation, fundamentally shaping the region's economy and ecology.

Geography and course

The river originates at Columbia Lake in the Rocky Mountain Trench of southeastern British Columbia, near the town of Canal Flats. It flows northwest through the Windermere Lake area before turning sharply south across the Canada–United States border into Washington at Lake Roosevelt, the reservoir behind Grand Coulee Dam. It then traces a sweeping arc through the Columbia Plateau, cutting through the Cascade Range via the dramatic Columbia River Gorge, a major National Scenic Area. Major tributaries joining its course include the Kootenay River, Pend Oreille River, Spokane River, Snake River, Deschutes River, and Willamette River. Its final segment forms the Oregon–Washington border before broadening into a massive estuary and discharging into the Pacific Ocean near Astoria, Oregon.

History and exploration

For millennia, the river and its basin have been home to numerous Indigenous peoples, including the Nez Perce, Yakama, Umatilla, and Warm Springs tribes. The first documented European sighting was by Spanish explorer Bruno de Heceta in 1775. American captain Robert Gray entered the river mouth in 1792, naming it after his ship, the Columbia Rediviva. The Lewis and Clark Expedition reached the river in 1805, mapping its lower reaches and establishing a U.S. claim to the region. Subsequent exploration and trade were dominated by the British North West Company and the Hudson's Bay Company, with key posts like Fort Vancouver established by John McLoughlin. The Oregon Treaty of 1846 finally established the river as the border between U.S. and British territories west of the Continental Divide.

Ecology and environment

The river's basin hosts a wide variety of biomes, from temperate rainforests in the Cascade Range to shrub-steppe in the Columbia Plateau. It was once one of the world's greatest salmon-producing river systems, with major runs of Chinook salmon, coho salmon, and steelhead. Other native fish species include Pacific lamprey and white sturgeon. The basin is a critical corridor for migratory birds along the Pacific Flyway. Significant environmental challenges stem from hydroelectric dams, which have altered river flow, temperature, and sediment transport, severely impacting anadromous fish populations. Pollution from agricultural runoff, industrial waste, and historical Hanford Site operations also affects water quality, leading to extensive conservation and restoration efforts led by agencies like the U.S. Environmental Protection Agency and the Columbia River Inter-Tribal Fish Commission.

Dams and economic uses

The river is the hydroelectric powerhouse of North America, with 14 major dams on its main stem, including the massive Grand Coulee Dam and Chief Joseph Dam in the U.S., and the Mica Dam and Revelstoke Dam in Canada. These projects, largely constructed under the Bonneville Power Administration and the U.S. Army Corps of Engineers, provide about one-third of the United States' hydropower. The dams also enable extensive irrigation for agriculture in the Columbia Basin Project, supporting crops like apples, wheat, and potatoes. The river is navigable to oceangoing vessels as far inland as Portland, Oregon, and to barge traffic via a system of locks and slackwater reservoirs to Lewiston, Idaho, facilitating the transport of grain, fuel, and other goods. Key ports include the Port of Portland and the Port of Vancouver USA.

Cultural significance

The river holds profound cultural and spiritual importance for the Indigenous peoples of the Northwest Plateau, central to their creation stories, diets, and ceremonies, as affirmed by treaties like the Treaty of 1855. It has inspired numerous works of art and literature, including the photography of Carleton Watkins and the films of Ken Burns. The river's history of exploration and development is interpreted at sites like the Columbia River Maritime Museum and Fort Clatsop. Annual events like the hydroplane races during Seafair on Lake Washington and the Bridge of the Gods crossing in the Cascade Locks celebrate its ongoing role in regional identity. Its dramatic landscapes are protected within the Columbia River Gorge National Scenic Area and several U.S. National Wildlife Refuges.

Category:Rivers of British Columbia Category:Rivers of Oregon Category:Rivers of Washington (state) Category:Columbia River Category:International rivers of North America