Columbia River

Columbia River
Columbia River from Rowena Crest with Interstate 84 on the right
Columbia River drainage basin
EtymologyCaptain Robert Gray's ship, Columbia Rediviva
Nickname(s)Big River, the River of the West, River Oregon
Native name
Location
CountryCanada, United States
ProvinceBritish Columbia
StateWashington, Oregon
CitiesRevelstoke, BC, Castlegar, BC, Trail, BC, Wenatchee, WA, East Wenatchee, WA, Tri-Cities, WA, The Dalles, OR, Hood River, OR, Portland, OR, Vancouver, WA, Longview, WA, Astoria, OR
Physical characteristics
SourceColumbia Lake
  locationBritish Columbia, Canada
  coordinates50°13′35″N 115°51′05″W / 50.22639°N 115.85139°W / 50.22639; -115.85139
  elevation2,690 ft (820 m)
MouthPacific Ocean, at Clatsop County, Oregon / Pacific County, Washington
  coordinates
46°14′39″N 124°3′29″W / 46.24417°N 124.05806°W / 46.24417; -124.05806
  elevation
0 ft (0 m)
Length1,243 mi (2,000 km)
Basin size258,000 sq mi (670,000 km2)
Discharge 
  locationAstoria (near mouth)
  average(Period: 1951–1980)265,000 cu ft/s (7,500 m3/s) (Period: 1969–2023)234,700 cu ft/s (6,650 m3/s)
Discharge 
  locationPort Westward
  average(Period: 1969–2023)233,700 cu ft/s (6,620 m3/s)
  minimum63,600 cu ft/s (1,800 m3/s)(Year: 2001)
  maximum864,000 cu ft/s (24,500 m3/s)(Year: 1996)
Discharge 
  locationThe Dalles
  average(Period: 1879–2023)188,500 cu ft/s (5,340 m3/s)
  minimum12,100 cu ft/s (340 m3/s)(Year: 1968)
  maximum1,240,000 cu ft/s (35,000 m3/s)(Year: 1894)
Discharge 
  locationPriest Rapids Dam
  average(1960–2023)118,200 cu ft/s (3,350 m3/s)
  minimum36,400 cu ft/s (1,030 m3/s)(Year: 1962)
  maximum533,000 cu ft/s (15,100 m3/s)(Year: 1961)
Discharge 
  locationUnited States and Canada international boundary
  average(Period: 1938– 2023)99,300 cu ft/s (2,810 m3/s)
  minimum21,200 cu ft/s (600 m3/s)(Year: 1944)
  maximum550,000 cu ft/s (16,000 m3/s)(Year: 1948)
Basin features
ProgressionPacific Ocean
River systemColumbia River
Tributaries 
  leftSpillimacheen River, Beaver River, Illecillewaet River, Incomappleux River, Kootenay River, Pend Oreille River, Spokane River, Crab Creek, Snake River, John Day River, Deschutes River, Willamette River
  rightKicking Horse River, Blaeberry River, Canoe River, Kettle River, Sanpoil River, Okanogan River, Entiat River, Wenatchee River, Yakima River, Lewis River, Cowlitz River

The Columbia River (Upper Chinook: Wimahl or Wimal; Sahaptin: Nch’i-Wàna or Nchi wana; Sinixt dialect swah'netk'qhu) is the largest river in the Pacific Northwest region of North America. The river forms in the Rocky Mountains of British Columbia, Canada. It flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state of Oregon before emptying into the Pacific Ocean. The river is 1,243 mi (2,000 km) long, and its largest tributary is the Snake River. Its drainage basin is roughly the size of France and extends into seven states of the United States and one Canadian province. The fourth-largest river in the United States by flow, the Columbia has the greatest flow of any river into the eastern Pacific.

The Columbia and its tributaries have been central to the region's culture and economy for thousands of years. They have been used for transportation since ancient times, linking the region's many cultural groups. The river system hosts many species of anadromous fish, which migrate between freshwater habitats and the saline waters of the Pacific Ocean. These fish—especially the salmon species—provided the core subsistence for native peoples.

The first documented European discovery of the Columbia River occurred when Spanish explorer Bruno de Heceta sighted the river's mouth in 1775. On May 11, 1792, a private American ship, Columbia Rediviva, under Captain Robert Gray from Boston became the first non-indigenous vessel to enter the river. Later in 1792, William Robert Broughton of the British Royal Navy commanding HMS Chatham as part of the Vancouver Expedition, navigated past the Oregon Coast Range and 100 miles (160 km) upriver to what is now Vancouver, Washington. In the following decades, fur-trading companies used the Columbia as a key transportation route. Overland explorers entered the Willamette Valley through the scenic, but treacherous Columbia River Gorge, and pioneers began to settle the valley in increasing numbers. Steamships along the river linked communities and facilitated trade; the arrival of railroads in the late 19th century, many running along the river, supplemented these links.

Since the late 19th century, public and private sectors have extensively developed the river. To aid ship and barge navigation, locks have been built along the lower Columbia and its tributaries, and dredging has opened, maintained, and enlarged shipping channels. Since the early 20th century, dams have been built across the river for power generation, navigation, irrigation, and flood control. The 14 hydroelectric dams on the Columbia's main stem and many more on its tributaries produce more than 44 percent of total U.S. hydroelectric generation. Production of nuclear power has taken place at two sites along the river. Plutonium for nuclear weapons was produced for decades at the Hanford Site, which is now the most contaminated nuclear site in the United States. These developments have greatly altered river environments in the watershed, mainly through industrial pollution and barriers to fish migration.