Columbia River

The Columbia begins its {{cvt|1,243|mi|km|abbr=on}} journey in the southern Rocky Mountain Trench in British Columbia (BC). Columbia Lake{{snds}} {{cvt|2,690|ft|m|abbr=on}} above sea level{{snds}} and the adjoining Columbia Wetlands form the river's headwaters. The trench is a broad, deep, and long glacial valley between the Canadian Rockies and the Columbia Mountains in BC. For its first {{cvt|200|mi|km|abbr=on}}, the Columbia flows northwest along the trench through Windermere Lake and the town of Invermere, a region known in BC as the Columbia Valley, then northwest to Golden and into Kinbasket Lake. Rounding the northern end of the Selkirk Mountains, the river turns sharply south through a region known as the Big Bend Country, passing through Revelstoke Lake and the Arrow Lakes. Revelstoke, the Big Bend, and the Columbia Valley combined are referred to in BC parlance as the Columbia Country. Below the Arrow Lakes, the Columbia passes the cities of Castlegar, located at the Columbia's confluence with the Kootenay River, and Trail, two major population centers of the West Kootenay region. The Pend Oreille River joins the Columbia about {{convert|2|mi|0}} north of the United States–Canada border.{{cite web |title = The Atlas of Canada: Toporama – Topographic Maps |publisher = Natural Resources Canada |year = 2015 |access-date = September 30, 2015 |url = http://atlas.gc.ca/toporama/en/index.html |archive-url = https://web.archive.org/web/20150509053449/http://atlas.gc.ca/toporama/en/index.html |archive-date = May 9, 2015 |url-status = live }}

File:Columbia River route on satellite image.jpg, in the United States. The maps show that the river, although flowing on average in a southwesterly direction from source to mouth, changes direction sharply from northwest to south at Big Bend in Canada, from south to west near Grand Coulee Dam in Washington, from west to south near Wenatchee, Washington, and from south to west near the Tri-Cities area in Washington.|Course of the Columbia River]]

The Columbia enters eastern Washington flowing south and turning to the west at the Spokane River confluence. It marks the southern and eastern borders of the Colville Indian Reservation and the western border of the Spokane Indian Reservation.{{cite web |last1 = Kowalski |first1 = Peter |last2 = Kaplan |first2 = Brian |last3 = Karus |first3 = Greg |title = Health Consultation |url = http://www.atsdr.cdc.gov/hac/pha/pha.asp?docid=1302&pg=1#back |work = Colville Federated Tribes |publisher = Agency for Toxic Substances and Disease Registry |date = March 7, 2001 |access-date = October 2, 2015 |archive-url = https://web.archive.org/web/20130403011248/http://www.atsdr.cdc.gov/HAC/pha/pha.asp?docid=1302&pg=1 |archive-date = April 3, 2013 |url-status = dead }} The river turns south after the Okanogan River confluence, then southeasterly near the confluence with the Wenatchee River in central Washington. This C-shaped segment of the river is also known as the "Big Bend". During the Missoula Floods 10{{ndash}}15,000 years ago, much of the floodwater took a more direct route south, forming the ancient river bed known as the Grand Coulee. After the floods, the river found its present course, and the Grand Coulee was left dry. The construction of the Grand Coulee Dam in the mid-20th century impounded the river, forming Lake Roosevelt, from which water was pumped into the dry coulee, forming the reservoir of Banks Lake.{{cite web |title = Columbia Basin Project |publisher = U.S. Department of the Interior, Bureau of Reclamation |year = 2009 |access-date = September 2, 2009 |url = http://www.usbr.gov/projects/Project.jsp?proj_Name=Columbia%20Basin%20Project |archive-url = https://web.archive.org/web/20150215125327/http://www.usbr.gov/projects/Project.jsp?proj_Name=Columbia%20Basin%20Project |archive-date = February 15, 2015 |url-status = dead |df = mdy-all }}

The river flows past The Gorge Amphitheatre, a prominent concert venue in the Northwest, then through Priest Rapids Dam, and then through the Hanford Nuclear Reservation. Entirely within the reservation is Hanford Reach, the only U.S. stretch of the river that is completely free-flowing, unimpeded by dams, and not a tidal estuary. The Snake River and Yakima River join the Columbia in the Tri-Cities population center. The Columbia makes a sharp bend to the west at the Washington–Oregon border. The river defines that border for the final {{cvt|309|mi|km|abbr=on}} of its journey.{{cite web|title=Oregon's {{Sic|hide=y|Publicly|-}}Owned Waterways|work=Public Ownership of Submerged and Submersible Land|publisher=Oregon Department of State Lands|access-date=March 9, 2008|url=http://www.oregon.gov/DSL/NAV/navigwaterways.shtml

|archive-url=https://web.archive.org/web/20100527193305/http://www.oregon.gov/DSL/NAV/navigwaterways.shtml|archive-date=May 27, 2010|url-status=dead}}

File:ColumbiaGorge CapeHorn.jpg facing east toward Beacon Rock]]

The Deschutes River joins the Columbia near The Dalles. Between The Dalles and Portland, the river cuts through the Cascade Range, forming the dramatic Columbia River Gorge. Via the gorge, the Columbia crosses the Cascades at a lower elevation than any other river. The gorge is known for its strong and steady winds, scenic beauty, and its role as an important transportation link.{{cite web |title = Columbia River Gorge National Scenic Area |archive-url = https://web.archive.org/web/20071209080927/http://www.fs.fed.us/r6/columbia/ |url = http://www.fs.fed.us/r6/columbia/ |publisher = U.S. Department of Agriculture: Forest Service |archive-date = December 9, 2007 }} The river continues west, bending sharply to the north-northwest near Portland and Vancouver, Washington, at the Willamette River confluence. Here the river slows considerably, dropping sediment that might otherwise form a river delta at the Columbia's mouth. Near Longview, Washington and the Cowlitz River confluence, the river turns west again. The Columbia empties into the Pacific Ocean just west of Astoria, Oregon, over the Columbia Bar, a shifting sandbar that makes the river's mouth one of the most hazardous stretches of water to navigate in the world.{{cite news |title = Columbia Pilot Pay Attracts Port's Eye |first = Ben |last = Jacklet |url = http://www.portlandtribune.com/news/story.php?story_id=26722 |work = Portland Tribune |date = October 19, 2004 |access-date = June 14, 2007 |archive-url = https://web.archive.org/web/20120206213802/http://www.portlandtribune.com/news/story.php?story_id=26722 |archive-date = February 6, 2012 |url-status = dead }} Because of the danger and the many shipwrecks near the mouth, it acquired a reputation as the "Graveyard of Ships".{{cite journal |last = Gibbs |first = Rafe |title = Guarding the Graveyard of Ships |url = https://books.google.com/books?id=oN0DAAAAMBAJ&q=1954+Popular+Mechanics+January&pg=PA128 |journal = Popular Mechanics |date = May 1954 |pages = 128–32 |access-date = March 1, 2012 |via = Google Books }}

The Columbia drains an area of about {{cvt|258,000|mi2|km2|abbr=on}}. Its drainage basin covers nearly all of Idaho, large portions of British Columbia, Oregon, and Washington, and ultimately all of Montana west of the Continental Divide, and small portions of Wyoming, Utah, and Nevada; the total area is similar to the size of France. Roughly {{cvt|745|mi|km|abbr=on}} of the river's length and 85 percent of its drainage basin are in the US.{{cite web |last = Lang |first = Bill |url = http://www.ccrh.org/river/history.htm |title = Columbia River |publisher = Center for Columbia River History |year = 2008 |access-date = April 2, 2008 |archive-url = https://web.archive.org/web/20150910111556/http://www.ccrh.org/river/history.htm |archive-date = September 10, 2015 |url-status = live }} The Columbia is the twelfth-longest river and has the sixth-largest drainage basin in the United States. In Canada, where the Columbia flows for {{cvt|498|mi|km|abbr=on}} and drains {{cvt|39,700|mi2|km2|abbr=on}}, the river ranks 23rd in length,This number was derived from the [https://web.archive.org/web/20060520164022/http://atlas.nrcan.gc.ca/site/english/learningresources/facts/rivers.html rivers list] published in The Atlas of Canada by Natural Resources Canada. and the Canadian part of its basin ranks 13th in size among Canadian basins.{{cite web |title = Frequently Asked Questions About Canada |work = The Atlas of Canada |publisher = Natural Resources Canada |year = 2008 |access-date = September 7, 2008 |url = http://atlas.nrcan.gc.ca/site/english/learningresources/facts/faq.html#rivers |archive-url = https://web.archive.org/web/20060604034510/http://atlas.nrcan.gc.ca/site/english/learningresources/facts/faq.html |archive-date = June 4, 2006 |url-status = dead }}

The Columbia shares its name with nearby places, such as British Columbia, as well as with landforms and bodies of water.

File:Columbia River Mouth and Bar.jpg map of the mouth of the Columbia River]]

With an average flow at the mouth of about {{cvt|265,000|ft3/s|m3/s|abbr=on}},{{cite web |first = J. C. |last = Kammerer |url = http://pubs.usgs.gov/of/1987/ofr87-242/ |title = Largest Rivers in the United States |publisher = United States Geological Survey |date = May 1990 |access-date = April 1, 2008 |archive-url = https://web.archive.org/web/20170129040848/https://pubs.usgs.gov/of/1987/ofr87-242/ |archive-date = January 29, 2017 |url-status = live }} the Columbia is the largest river by discharge flowing into the Pacific from the Americas{{cite web |title=Legend and Legacy: Fifty Years of Defense Production at the Hanford Site |first = Michele |last = Gerber |year = 1992 |url = http://www.washington.edu/uwired/outreach/cspn/Website/Classroom%20Materials/Curriculum%20Packets/Cold%20War%20&%20Red%20Scare/Documents/51.html |publisher = University of Washington Center for the Study of the Pacific Northwest |access-date = January 26, 2008 |archive-url = https://web.archive.org/web/20170527203435/http://www.washington.edu/uwired/outreach/cspn/Website/Classroom%20Materials/Curriculum%20Packets/Cold%20War%20%26%20Red%20Scare/Documents/51.html |archive-date = May 27, 2017 |url-status = live |df = mdy-all }} and is the fourth-largest by volume in the U.S. The average flow where the river crosses the international border between Canada and the United States is {{cvt|2,790|m3/s|cuft/s|abbr=on}} from a drainage basin of {{cvt|102,800|km2|mi2|abbr=on}}. This amounts to about 15 percent of the entire Columbia watershed. The Columbia's highest recorded flow, measured at The Dalles, was {{cvt|1,240,000|ft3/s|m3/s|abbr=on}} in June 1894, before the river was dammed.{{cite web |url = http://waterdata.usgs.gov/nwis/uv?14105700 |title = USGS Real-Time Water Data for USGS 14105700 Columbia River at the Dalles, OR |publisher = United States Geological Survey |access-date = August 6, 2008 |archive-url = https://web.archive.org/web/20140715004022/http://waterdata.usgs.gov/nwis/uv?14105700 |archive-date = July 15, 2014 |url-status = live }} The lowest flow recorded at The Dalles was {{cvt|12,100|ft3/s|m3/s|abbr=on}} on April 16, 1968, and was caused by the initial closure of the John Day Dam, {{cvt|28|mi|km|abbr=on}} upstream. The Dalles is about {{cvt|190|mi|km|abbr=on}} from the mouth; the river at this point drains about {{cvt|237,000|mi2|km2|abbr=on}} or about 91 percent of the total watershed. Flow rates on the Columbia are affected by many large upstream reservoirs, many diversions for irrigation, and, on the lower stretches, reverse flow from the tides of the Pacific Ocean. The National Ocean Service observes water levels at six tide gauges and issues tide forecasts for twenty-two additional locations along the river between the entrance at the North Jetty and the base of Bonneville Dam, its head of tide.{{cite web |author = NOAA Center for Operational Oceanographic Products and Services |title = NOAA Tide Predictions |publisher = U.S. Department of Commerce |year = 2013 |url = https://tidesandcurrents.noaa.gov/tide_predictions.html?gid=1415 |access-date = April 8, 2015 |archive-url = https://web.archive.org/web/20161220030719/https://tidesandcurrents.noaa.gov/tide_predictions.html?gid=1415 |archive-date = December 20, 2016 |url-status = live }}

{{Bar chart

| title = Columbia River at Port Westward, 86 km from the mouth ({{coord|46|10|55.74|N|123|11|11.0148|W}}), 1992–2023:{{cite web|url=https://waterdata.usgs.gov/nwis/inventory?site_no=14246900&agency_cd=USGS|title=USGS 14246900 COLUMBIA RIVER AT PORT WESTWARD, NEAR QUINCY, OR}}

| label_type = Year

| data_type = Average discharge (m³/s)

| bar_width = 18

| width_units = em

| data_max = 9,600

| label1 = 2023

| data1 = 5,165

| label2 = 2022

| data2 = 6,986

| label3 = 2021

| data3 = 5,397

| label4 = 2020

| data4 = 5,839

| label5 = 2019

| data5 = 5,386

| label6 = 2018

| data6 = 7,221

| label7 = 2017

| data7 = 8,795

| label8 = 2016

| data8 = 6,343

| label9 = 2015

| data9 = 5,862

| label10= 2014

| data10 =7,280

| label11= 2013

| data11 =6,963

| label12 =2012

| data12 =8,481

| label13 =2011

| data13 =8,852

| label14=2010

| data14=5,847

| label15=2009

| data15=5,998

| label16=2008

| data16=6,652

}}

{{Bar chart

| title = (continues)

| label_type = Year

| data_type = Average discharge (m³/s)

| bar_width = 18

| width_units = em

| data_max = 9,600

| label1=2007

| data1=6,524

| label2=2006

| data2=6,830

| label3=2005

| data3=5,213

| label4=2004

| data4=5,505

| label5=2003

| data5=5,913

| label6=2002

| data6=6,230

| label7=2001

| data7=3,964

| label8=2000

| data8=6,567

| label9=1999

| data9=8,487

| label10=1998

| data10=6,943

| label11=1997

| data11=9,578

| label12=1996

| data12=9,325

| label13=1995

| data13=6,315

| label14=1994

| data14=4,845

| label15=1993

| data15=6,176

| label16=1992

| data16=5,179

}}

{{Bar chart

| title = Columbia River multiannual average discharge:{{cite web|url=https://www.usgs.gov|title=USGS}}{{cite web|url=https://www.riversnetwork.org/V1/index.php/component/content/?view=article&id=33&catid=184&Itemid=179|title=Rivers Network - Columbia River|first=Eric|last=Tilman|website=Rivers Network}}

| label_type = Location, period

| data_type = Average discharge (m³/s)

| bar_width = 14

| width_units = em

| data_max = 7,134

| label1=Astoria, 1892–2023

| data1=7,134

| label2=Port Westward, 1879–2023

| data2=7,048

| label3=The Dalles, 1879–2023^*

| data3=5,338

| label5=International boundary, 1938–2023

| data5=2,812

}}

^*1858–1899: 6,280 m³/s

{{See also|Geology of the Pacific Northwest|Missoula Floods}}

File:Drum-Heller-Channels.jpg, part of the Channeled Scablands formed by the Missoula Floods]]

When the rifting of Pangaea, due to the process of plate tectonics, pushed North America away from Europe and Africa and into the Panthalassic Ocean (ancestor to the modern Pacific Ocean), the Pacific Northwest was not part of the continent. As the North American continent moved westward, the Farallon Plate subducted under its western margin. As the plate subducted, it carried along island arcs which were accreted to the North American continent, resulting in the creation of the Pacific Northwest between 150 and 90 million years ago.{{sfn|Bishop|2003|pp=13–14}} The general outline of the Columbia Basin was not complete until between 60 and 40 million years ago, but it lay under a large inland sea later subject to uplift.{{cite web |title = The Geologic Story of the Columbia Basin |url = https://www.bpa.gov/power/pl/columbia/4-geology.htm |publisher = Bonneville Power Administration |access-date = June 20, 2017 |archive-url = https://web.archive.org/web/20170708070906/https://www.bpa.gov/Power/pl/columbia/4-geology.htm |archive-date = July 8, 2017 |url-status = live }} Between 50 and 20 million years ago, from the Eocene through the Miocene eras, tremendous volcanic eruptions frequently modified much of the landscape traversed by the Columbia.{{sfn|Bishop|2003|pp=86, 128}} The lower reaches of the ancestral river passed through a valley near where Mount Hood later arose. Carrying sediments from erosion and erupting volcanoes, it built a {{convert|2|mi|km|adj=on}} thick delta that underlies the foothills on the east side of the Coast Range near Vernonia in northwestern Oregon.{{sfn|Bishop|2003|p=98}} Between 17 million and 6 million years ago, huge outpourings of flood basalt lava covered the Columbia River Plateau and forced the lower Columbia into its present course.{{sfn|Bishop|2003|pp=132, 150}} The modern Cascade Range began to uplift 5 to 4 million years ago.{{cite web |title = The Cascade Episode |url = https://www.bpa.gov/power/pl/columbia/4-geology.htm |publisher = Burke Museum |year = 2016 |access-date = June 20, 2017 |archive-url = https://web.archive.org/web/20170708070906/https://www.bpa.gov/Power/pl/columbia/4-geology.htm |archive-date = July 8, 2017 |url-status = live }} Cutting through the uplifting mountains, the Columbia River significantly deepened the Columbia River Gorge.{{sfn|Bishop|2003|p=195}}

The river and its drainage basin experienced some of the world's greatest known catastrophic floods toward the end of the last ice age. The periodic rupturing of ice dams at Glacial Lake Missoula resulted in the Missoula Floods, with discharges exceeding the combined flow of all the other rivers in the world, dozens of times over thousands of years. The exact number of floods is unknown, but geologists have documented at least 40; evidence suggests that they occurred between about 19,000 and 13,000 years ago.{{sfn|Bishop|2003|pp=226–29}}

File:ColumbiaRGorgePano.jpg in Washington]]

The floodwaters rushed across eastern Washington, creating the channeled scablands, which are a complex network of dry canyon-like channels, or coulees that are often braided and sharply gouged into the basalt rock underlying the region's deep topsoil. Numerous flat-topped buttes with rich soil stand high above the chaotic scablands.{{sfn|Stelling|Tucker|2007|pp=213–14, 230}} Constrictions at several places caused the floodwaters to pool into large temporary lakes, such as Lake Lewis, in which sediments were deposited. Water depths have been estimated at {{convert|1000|ft|m}} at Wallula Gap{{sfn|Bishop|2003|p=227}} and {{convert|400|ft|m}} over modern Portland, Oregon.{{sfn|Houck|Cody|2000|p=19}} Sediments were also deposited when the floodwaters slowed in the broad flats of the Quincy, Othello, and Pasco Basins.{{sfn|Stelling|Tucker|2007|pp=213–14, 230}} The floods' periodic inundation of the lower Columbia River Plateau deposited rich sediments; 21st-century farmers in the Willamette Valley "plow fields of fertile Montana soil and clays from Washington's Palouse".{{sfn|Bishop|2003|p=227}}

Over the last several thousand years a series of large landslides have occurred on the north side of the Columbia River Gorge, sending massive amounts of debris south from Table Mountain and Greenleaf Peak into the gorge near the present site of Bonneville Dam. The most recent and significant is known as the Bonneville Slide, which formed a massive earthen dam, filling {{convert|3.5|mi|km}} of the river's length.{{cite news |first = Richard L. |last = Hill |title = Radiocarbon Dates Indicate the Bonneville Landslide May Be Far Younger Than Thought |work = The Oregonian |date = September 9, 1999 |url = http://landslides.usgs.gov/recent/archives/1999bonneville.php |access-date = September 7, 2009 |url-status = dead |archive-url = https://web.archive.org/web/20100923023338/http://landslides.usgs.gov/recent/archives/1999bonneville.php |archive-date = September 23, 2010 |df = mdy }}{{cite journal |last = Reynolds |first = Nathaniel D. |date = December 2001 |title = Dating the Bonneville Landslide with Lichenometry |journal = Washington Geology |volume = 29 |issue = 3/4 |pages = 11–16 |url = http://www.dnr.wa.gov/Publications/ger_washington_geology_2001_v29_no3-4.pdf |access-date = September 7, 2009 |archive-url = https://web.archive.org/web/20150630032045/http://www.dnr.wa.gov/Publications/ger_washington_geology_2001_v29_no3-4.pdf |archive-date = June 30, 2015 |url-status = live }} Various studies have placed the date of the Bonneville Slide anywhere between 1060 and 1760 AD; the idea that the landslide debris present today was formed by more than one slide is relatively recent and may explain the large range of estimates. It has been suggested that if the later dates are accurate there may be a link with the 1700 Cascadia earthquake.{{cite news |first = Richard L. |last = Hill |title = Science – Landslide Sleuths |work = The Oregonian |date = May 15, 2002 |url = https://earthquake.usgs.gov/regional/pacnw/paleo/greateq/20020515.html |access-date = September 7, 2009 |archive-url = https://web.archive.org/web/20080906210151/http://earthquake.usgs.gov/regional/pacnw/paleo/greateq/20020515.html |archive-date = September 6, 2008 |url-status = dead }} The pile of debris resulting from the Bonneville Slide blocked the river until rising water finally washed away the sediment. It is not known how long it took the river to break through the barrier; estimates range from several months to several years.{{cite journal |last = O'Connor |first = Jim E. |date = September 2004 |title = The Evolving Landscape of the Columbia River Gorge: Lewis and Clark and Cataclysms on the Columbia |journal = Oregon Historical Quarterly |volume = 105 |issue = 3 |pages = 390–421 |doi = 10.1353/ohq.2004.0043 |jstor = 20615448 |s2cid = 131976728 }} Much of the landslide's debris remained, forcing the river about {{convert|1.5|mi|km}} south of its previous channel and forming the Cascade Rapids.{{cite web |last1 = Norman |first1 = David K. |last2 = Roloff |first2 = Jaretta M. |title = A Self-Guided Tour of the Geology of the Columbia River Gorge—Portland Airport to Skamania Lodge, Stevenson, Washington |publisher = Washington Department of Natural Resources, Division of Geology and Earth Resources |date = March 2004 |url = http://www.dnr.wa.gov/Publications/ger_ofr2004-7_geol_tour_columbia_river_gorge.pdf |access-date = September 8, 2009 |archive-url = https://web.archive.org/web/20170131051201/http://file.dnr.wa.gov/publications/ger_ofr2004-7_geol_tour_columbia_river_gorge.pdf |archive-date = January 31, 2017 |url-status = live }} In 1938, the construction of Bonneville Dam inundated the rapids as well as the remaining trees that could be used to refine the estimated date of the landslide.{{sfn|Rybář|Stemberk|Wagner|2002|p=695}}

In 1980, the eruption of Mount St. Helens deposited large amounts of sediment in the lower Columbia, temporarily reducing the depth of the shipping channel by {{convert|26|ft|m}}.{{cite web |url = http://pubs.usgs.gov/fs/2000/fs036-00/ |title = Mount St. Helens |publisher = United States Geological Survey |access-date = September 10, 2008 |archive-url = https://web.archive.org/web/20130512162409/http://pubs.usgs.gov/fs/2000/fs036-00/ |archive-date = May 12, 2013 |url-status = live }}

File:Chief Joseph.jpg of the Nez Perce people]]

Humans have inhabited the Columbia's watershed for more than 15,000 years, with a transition to a sedentary lifestyle based mainly on salmon starting about 3,500 years ago.{{sfn|National Research Council (U.S.)|2004|p=18}} In 1962, archaeologists found evidence of human activity dating back 11,230 years at the Marmes Rockshelter, near the confluence of the Palouse and Snake rivers in eastern Washington. In 1996 the skeletal remains of a 9,000-year-old prehistoric man (dubbed Kennewick Man) were found near Kennewick, Washington. The discovery rekindled debate in the scientific community over the origins of human habitation in North America and sparked a protracted controversy over whether the scientific or Native American community was entitled to possess and/or study the remains.{{cite magazine |title = Who Were The First Americans? |magazine = Time |publisher = Time, Inc. |date = March 5, 2006 |first1 = Michael D. |last1 = Lemonick |last2 = Dorfman |first2 = Andrea |last3 = Cray |first3 = Dan |url = http://www.time.com/time/magazine/article/0,9171,1169905,00.html |access-date = April 3, 2008 |url-access=subscription |archive-url = https://web.archive.org/web/20130823143721/http://www.time.com/time/magazine/article/0%2C9171%2C1169905%2C00.html |archive-date = August 23, 2013 |url-status = dead |df = mdy-all }}

Many different Native Americans and First Nations peoples have a historical and continuing presence on the Columbia. South of the Canada–US border, the Colville, Spokane, Coeur d'Alene, Yakama, Wanapum, Nez Perce, Cayuse, Palus, Umatilla, Cowlitz, and the Confederated Tribes of Warm Springs live along the US stretch. Along the upper Snake River and Salmon River, the Shoshone Bannock tribes are present. The Sinixt or Lakes people lived on the lower stretch of the Canadian portion,{{sfn|Pryce|1999|p=7}} while above that the Shuswap people (Secwepemc in their own language) reckon the whole of the upper Columbia east to the Rockies as part of their territory.[http://shuswapwatershed.ca/pdf/Shuswap_the_Name.pdf Shuswap: What's in a Name, Jim Cooperman, in A Shuswap Passion column for the Shuswap Market News, shuswapwatershed.ca website] {{Webarchive|url=https://web.archive.org/web/20131221183113/http://shuswapwatershed.ca/pdf/Shuswap_the_Name.pdf |date=December 21, 2013 }} (PDF) The Canadian portion of the Columbia Basin outlines the traditional homelands of the Canadian Kootenay–Ktunaxa.

The Chinook tribe, which is not federally recognized, who live near the lower Columbia River, call it {{Lang|wac|Wimahl}} or {{Lang|wac|Wimal}} in the Upper Chinook (Kiksht) language,{{cite encyclopedia |last = Oldham |first = Kit |title = Captain Robert Gray Becomes the First Non-Indian Navigator to Enter the Columbia River, Which He Later Names, on May 11, 1792 |encyclopedia = The Online Encyclopedia of Washington State History |publisher = HistoryLink.org |date = January 13, 2003 |url = http://www.historylink.org/index.cfm?DisplayPage=output.cfm&File_Id=5051 |access-date = April 1, 2008 |archive-url = https://web.archive.org/web/20150929041353/http://www.historylink.org/index.cfm?DisplayPage=output.cfm&File_Id=5051 |archive-date = September 29, 2015 |url-status = live }} and it is Nch’i-Wàna or Nchi wana to the Sahaptin (Ichishkíin Sɨ́nwit)-speaking peoples of its middle course in present-day Washington.{{sfn|Hunn|1990|p=3}} The river is known as {{lang|sal|swah'netk'qhu}} by the Sinixt people, who live in the area of the Arrow Lakes in the river's upper reaches in Canada.{{sfn|Dove (Quintasket)|1990|pp=100–01}} All three terms essentially mean "the big river".

Oral histories describe the formation and destruction of the Bridge of the Gods, a land bridge that connected the Oregon and Washington sides of the river in the Columbia River Gorge. The bridge, which aligns with geological records of the Bonneville Slide, was described in some stories as the result of a battle between gods, represented by Mount Adams and Mount Hood, in their competition for the affection of a goddess, represented by Mount St. Helens.{{sfn|Satterfield|2003|p=82}} Native American stories about the bridge differ in their details but agree in general that the bridge permitted increased interaction between tribes on the north and south sides of the river.{{sfn|Dohnal|2003|pp=12–14}}{{sfn|Clark|2003|pp=20–25}}

Horses, originally acquired from Spanish New Mexico, spread widely via native trade networks, reaching the Shoshone of the Snake River Plain by 1700. The Nez Perce, Cayuse, and Flathead people acquired their first horses around 1730.{{sfn|Meinig|1995|pp=23–25, 493, 496}}{{sfn|Boyd|1996|pp=12–13}} Along with horses came aspects of the emerging plains culture, such as equestrian and horse training skills, greatly increased mobility, hunting efficiency, trade over long distances, intensified warfare, the linking of wealth and prestige to horses and war, and the rise of large and powerful tribal confederacies. The Nez Perce and Cayuse kept large herds and made annual long-distance trips to the Great Plains for bison hunting, adopted the plains culture to a significant degree, and became the main conduit through which horses and the plains culture diffused into the Columbia River region. Other peoples acquired horses and aspects of the plains culture unevenly. The Yakama, Umatilla, Palus, Spokane, and Coeur d'Alene maintained sizable herds of horses and adopted some of the plains cultural characteristics, but fishing and fish-related economies remained important. Less affected groups included the Molala, Klickitat, Wenatchi, Okanagan, and Sinkiuse-Columbia peoples, who owned small numbers of horses and adopted few plains culture features. Some groups remained essentially unaffected, such as the Sanpoil and Nespelem people, whose culture remained centered on fishing.{{sfn|Meinig|1995|pp=23–25, 493, 496}}

Natives of the region encountered foreigners at several times and places during the 18th and 19th centuries. European and American vessels explored the coastal area around the mouth of the river in the late 18th century, trading with local natives. The contact would prove devastating to the indigenous Chinookan speaking peoples; a large portion of their population was wiped out by a smallpox epidemic. Canadian explorer Alexander Mackenzie crossed what is now interior British Columbia in 1793.{{sfn|Boyd|1996|pp=12–13}} From 1805 to 1806, the Lewis and Clark Expedition entered the Oregon Country along the Clearwater and Snake rivers, and encountered numerous small settlements of natives. Their records recount tales of hospitable traders who were not above stealing small items from the visitors. They also noted brass teakettles, a British musket, and other artifacts that had been obtained in trade with coastal tribes.{{sfn|Ulrich|2007|p=8}} From the earliest contact with westerners, the natives of the mid- and lower Columbia were not tribal, but instead congregated in social units no larger than a village, and more often at a family level; these units would shift with the season as people moved about, following the salmon catch up and down the river's tributaries.{{sfn|Boyd|1996|pp=4–7}}

Sparked by the 1847 Whitman Massacre, a number of violent battles were fought between American settlers and the region's natives.{{cite journal |title = Review: Marcus Whitman, Pathfinder and Patriot |author = Myron Eells |volume = 42 |year = 1910 |jstor = 199162 |journal = Bulletin of the American Geographical Society |doi = 10.2307/199162 |issue = 4 |pages = 299 |hdl = 2027/hvd.32044086439460 |hdl-access = free }} The subsequent wars over Northwest territory, especially the Yakima War, decimated the native population and removed much land from native control.{{cite web |title = Oregon History: Indian Wars |work = Oregon Blue Book |url = https://sos.oregon.gov/blue-book/Pages/facts/history/pre-indian.aspx |access-date = September 3, 2009 |archive-url = https://web.archive.org/web/20181024035527/https://sos.oregon.gov/blue-book/Pages/facts/history/pre-indian.aspx |archive-date = October 24, 2018 |url-status = live }} As years progressed, the right of natives to fish along the Columbia became the central issue of contention with the states, commercial fishers, and private property owners. The US Supreme Court upheld fishing rights in landmark cases in 1905 and 1918,{{sfn|Ulrich|2007|p=14}} as well as the 1974 case United States v. Washington, commonly called the Boldt Decision.

File:Celilo Falls Lee.jpg

Fish were central to the culture of the region's natives, both as sustenance and as part of their religious beliefs.{{sfn|Ulrich|2007|p=6}} Natives drew fish from the Columbia at several major sites, which also served as trading posts. Celilo Falls, located east of the modern city of The Dalles, was a vital hub for trade and the interaction of different cultural groups,{{sfn|Boyd|1996|pp=4–7}} being used for fishing and trading for 11,000 years. Prior to contact with westerners, villages along this {{convert|9|mi|km|adj=on}} stretch may have at times had a population as great as 10,000.{{sfn|Barber|2005|pp=20–21}} The site drew traders from as far away as the Great Plains.Attributed to anthropologist Philip Drucker in Cultures of the North Pacific Coast in Netboy's The Columbia River Salmon and Steelhead Trout.{{sfn|Netboy|1980|p=14}}

The Cascades Rapids of the Columbia River Gorge, and Kettle Falls and Priest Rapids in eastern Washington, were also major fishing and trading sites.{{cite web |title = Kettle Falls |first = Cassandra |last = Tate |work = HistoryLink.org |url = http://www.historylink.org/index.cfm?DisplayPage=output.cfm&File_Id=7577 |date = December 27, 2005 |archive-url = https://web.archive.org/web/20150924050633/http://www.historylink.org/index.cfm?DisplayPage=output.cfm&File_Id=7577 |archive-date = September 24, 2015 |url-status = live }}{{cite encyclopedia |last = Willingham |first = William F. |title = Cascade Locks |encyclopedia = Oregon Encyclopedia |url = http://www.oregonencyclopedia.org/articles/cascade_locks/ |access-date = September 8, 2009 |archive-url = https://web.archive.org/web/20170620234804/http://www.oregonencyclopedia.org/articles/cascade_locks/#.WVZ6w1GQyih |archive-date = June 20, 2017 |url-status = live }}

In prehistoric times the Columbia's salmon and steelhead runs numbered an estimated annual average of 10 to 16 million fish. In comparison, the largest run since 1938 was in 1986, with 3.2 million fish entering the Columbia.{{cite web |title = Columbia River Fish Runs and Fisheries |publisher = Washington Department of Fish and Wildlife, and Oregon Department of Fish and Wildlife |date = August 2002 |pages = 2–3, 6, 47, 62 |url = http://wdfw.wa.gov/fish/columbia/2000_status_report_text.pdf |archive-url = https://web.archive.org/web/20060926091324/http://wdfw.wa.gov/fish/columbia/2000_status_report_text.pdf |archive-date = September 26, 2006 }} The annual catch by natives has been estimated at {{convert|42|e6lbs|tonne|abbr=off|sp=us}}.{{sfn|Wilkinson|2005|pp=159, 165}} The most important and productive native fishing site was located at Celilo Falls, which was perhaps the most productive inland fishing site in North America.{{cite journal |last = Cain |first = Allen |date = September 2007 |title = Boils Swell & Whorl Pools |journal = Oregon Historical Quarterly |volume = 108 |issue = 4 |pages = 546–560 |jstor = 20615793}} The falls were located at the border between Chinookan- and Sahaptian-speaking peoples and served as the center of an extensive trading network across the Pacific Plateau.{{sfn|Ronda|1984|p=170}} Celilo was the oldest continuously inhabited community on the North American continent.{{sfn|Dietrich|1995|p=52}}

Salmon canneries established by white settlers beginning in 1866 had a strong negative impact on the salmon population, and in 1908 US president Theodore Roosevelt observed that the salmon runs were but a fraction of what they had been 25 years prior.{{cite web |title = Columbia River History: Commercial Fishing |publisher = Northwest Power and Conservation Council |url = http://www.nwcouncil.org/history/commercialfishing.asp |year = 2010 |access-date = January 26, 2012 |archive-url = https://web.archive.org/web/20130210064923/http://www.nwcouncil.org/history/commercialfishing.asp |archive-date = February 10, 2013 |url-status = live }}

As river development continued in the 20th century, each of these major fishing sites was flooded by a dam, beginning with Cascades Rapids in 1938. The development was accompanied by extensive negotiations between natives and US government agencies. The Confederated Tribes of Warm Springs, a coalition of various tribes, adopted a constitution and incorporated after the 1938 completion of the Bonneville Dam flooded Cascades Rapids;{{cite web |title = The Oregon Story |url = http://www.opb.org/programs/oregonstory/tribal_econ/timeline.html |publisher = Oregon Public Broadcasting |year = 2001 |access-date = March 19, 2008 |archive-url = https://web.archive.org/web/20080318041442/http://www.opb.org/programs/oregonstory/tribal_econ/timeline.html |archive-date = March 18, 2008 |url-status = live }} Still, in the 1930s, there were natives who lived along the river and fished year round, moving along with the fish's migration patterns throughout the seasons.{{sfn|Ulrich|2007|p=5}} The Yakama were slower to do so, organizing a formal government in 1944.{{sfn|Ulrich|2007|p=11}} In the 21st century, the Yakama, Nez Perce, Umatilla, and Warm Springs tribes all have treaty fishing rights along the Columbia and its tributaries.{{sfn|Wilkinson|2005|pp=159, 165}}

In 1957 Celilo Falls was submerged by the construction of The Dalles Dam, and the native fishing community was displaced.{{sfn|Dietrich|1995|p=52}} The affected tribes received a $26.8 million settlement for the loss of Celilo and other fishing sites submerged by The Dalles Dam.{{sfn|Dietrich|1995|p=376}} The Confederated Tribes of Warm Springs used part of its $4 million settlement to establish the Kah-Nee-Ta resort south of Mount Hood.

In 1977, 75 indigenous fishermen of the Yakama Tribe were arrested in a federal sting operation which claimed that fishermen were poaching up to 40,000 fish in the Columbia River. Fishermen placed on trial received sentences ranging from six months to five years. The federal government pinned Yakama Tribe member David Sohappy ringleader of the operation. After the trial ended, it was determined that the fish were not poached, but driven away because of harmful chemicals present in the power plant. These harmful chemicals mainly consisted of aluminum. This event is commonly known today as the Salmon Scam.{{Cite web |last=Schick |first=Tony |date=September 24, 2022 |title=The racism, and resilience, behind today's Pacific Northwest salmon crisis |url=https://www.opb.org/article/2022/09/24/racism-endangered-salmon-federal-policy-northwest-tribes/ |access-date=2024-05-02 |website=opb |language=en}}

Shortly after the Salmon Scam, many Columbia River-based indigenous tribes received federally recognized status. The Siletz Tribe was the first to restore its federal recognition in 1977, followed by the Cow Creek Band of the Umpqua Tribe in 1982, the Grand Ronde Tribe in 1983, the Lower Umpqua Tribe, Siuslaw Tribe, and Coos Tribe in 1984, the Klamath Tribe in 1986, and the Coquille Tribe in 1989.{{Cite web |last=Guggemos |first=Eva |date=February 27, 2024 |title=LibGuides: Indigenous History of Oregon: Timeline |url=https://pacificu.libguides.com/c.php?g=1050460&p=7794169 |access-date=2024-05-02 |website=pacificu.libguides.com |language=en}} While all the aforementioned tribes received federally recognized status, the Chinook Indian Nation had their federal recognition revoked in 2002 by the Bush administration, and are fighting to have it restored.{{Cite web |last=Reyna |first=Luna |date=2023-02-01 |title=The Chinook Indian Tribe calls for restoration of federal recognition |url=http://prismreports.org/2023/02/01/chinook-indian-tribe-calls-restoration-federal-recognition/ |access-date=2024-05-02 |website=Prism |language=en-US}}

In 2023, members of the Yakama Nation expressed their dismay for the construction of a Goldendale-based pumped hydroelectric energy storage project. Jeremy Takala of the Yakama Nation embodies Yakama belief on the importance of Columbia River crops to food and medicine, stating "the [Goldendale] project being proposed here, it will definitely impact our life".  The Goldendale-pumped hydro storage unit could allow for reused water use in reservoirs, which would be placed on mountainous terrain overlooking the Columbia River. The mountainous terrain where the unit would be placed in is Juniper Point, referred to by the Yakama as Pushpum. Pushpum has rock formations, as well as food and medicine capabilities that are essential to the Yakama. Members of the Yakama tribe wish for consent on the Goldendale project, as opposed to consultation.{{Cite web |last=Williams |first=Kale |date=July 27, 2023 |title=Tribes raise objections to renewable energy project in Columbia River Gorge |url=https://www.kgw.com/article/tech/science/environment/renewable-energy-project-columbia-river-gorge-tribes/283-24fc5c1f-7bdc-4954-9e73-9b91110a568a |access-date=2024-05-02 |website=kgw.com |language=en-US}}

{{See also|History of Oregon|History of British Columbia|History of Washington (state)|Oregon Country|History of the west coast of North America}}

File:Cascade Columbia River.jpg, painted by James W. Alden, 1857]]

Some historians {{Who|date=August 2022}} believe that Japanese or Chinese vessels blown off course reached the Northwest Coast long before Europeans—possibly as early as 219 BCE. Historian Derek Hayes claims that "It is a near certainty that Japanese or Chinese people arrived on the northwest coast long before any European."{{sfn|Hayes|1999|p=9}}{{Citation needed|date=August 2022|reason=Single author for this claim means it could be seen as dubious.}} It is unknown whether they landed near the Columbia.

The Maris Pacifici map published in 1589 features on the west coast of North-America an intriguing resemblance of two major coastline features: the mouth of the Columbia River identified as "Rio Grande" and the delta of the Fraser River labeled "Baia de las isleas". These rivers may have been too sighted by European visitors long before official records would confirm nearly 200 years later. In spite of limited evidence of Francis Drake expedition 1579 whereabouts in the Pacific Northwest, Pacific Northwest BC history commentator Sam Bawlf posited that the Ortelius mapped coastal features were a proof that Drake sighted the mouth of the Columbia and the Fraser River delta.Samuel Bawlf, The Secret Voyage of Sir Francis Drake 1577-1580, Douglas & McIntyre, 2003, pages 303 and 316 Evidence exists that Spanish castaways reached the shore in 1679 and traded with the Clatsop; if these were the first Europeans to see the Columbia, they failed to send word home to Spain.{{sfn|Hayes|1999a}}{{Citation needed|date=August 2022|reason=Single author for this claim means it could be seen as dubious.}}

In the 18th century, there was strong interest in discovering a Northwest Passage that would permit navigation between the Atlantic (or inland North America) and the Pacific Ocean. Many ships in the area, especially those under Spanish and British command, searched the northwest coast for a large river that might connect to Hudson Bay or the Missouri River. The first documented European discovery of the Columbia River was that of Bruno de Heceta, who in 1775 sighted the river's mouth. On the advice of his officers, he did not explore it, as he was short-staffed and the current was strong. He considered it a bay, and called it Ensenada de Asunción (Assumption Cove). Later Spanish maps, based on his sighting, showed a river, labeled Río de San Roque (The Saint Roch River), or an entrance, called Entrada de Hezeta, named for Bruno de Hezeta, who sailed the region.{{sfn|Hayes|1999a}} Following Hezeta's reports, British maritime fur trader Captain John Meares searched for the river in 1788 but concluded that it did not exist.{{cite web |title = Cape Disappointment State Park |url = https://www.nps.gov/lewi/planyourvisit/caped.htm |year = 2006 |publisher = National Park Service |access-date = September 4, 2009 |url-status = dead |archive-url = https://web.archive.org/web/20090831031245/https://www.nps.gov/lewi/planyourvisit/caped.htm |archive-date = August 31, 2009 |df = mdy }} He named Cape Disappointment for the non-existent river, not realizing the cape marks the northern edge of the river's mouth.{{sfn|Denton|1924|p=174}}

What happened next would form the basis for decades of both cooperation and dispute between British and American exploration of, and ownership claim to, the region. Royal Navy commander George Vancouver sailed past the mouth in April 1792 and observed a change in the water's color, but he accepted Meares' report and continued on his journey northward. Later that month, Vancouver encountered the American captain Robert Gray at the Strait of Juan de Fuca. Gray reported that he had seen the entrance to the Columbia and had spent nine days trying but failing to enter.{{sfn|Roberts|2005|p=23}}

File:Western North America 1778.png's map from 1778, showing the River of the West, New Albion, Lake Winnipeg, and the Mountains of Bright Stone]]

On May 12, 1792, Gray returned south and crossed the Columbia Bar, becoming the first known explorer of European descent to enter the river. Gray's fur trading mission had been financed by Boston merchants, who outfitted him with a private vessel named Columbia Rediviva; he named the river after the ship on May 18.{{sfn|Hayes|1999a}}{{sfn|Loy|Allan|Buckley|Meacham|2001|p=24}} Gray spent nine days trading near the mouth of the Columbia, then left without having gone beyond {{convert|13|mi|km}} upstream. The farthest point reached was Grays Bay at the mouth of Grays River.{{cite web |title = Captain Robert Gray Explores Grays Bay and Charts the Mouth of Grays River in May 1792 |publisher = HistoryLink.org |url = http://www.historylink.org/index.cfm?displaypage=output.cfm&file_id=5052 |access-date = May 16, 2009 |archive-url = https://web.archive.org/web/20150924093133/http://www.historylink.org/index.cfm?displaypage=output.cfm&file_id=5052 |archive-date = September 24, 2015 |url-status = live }} Gray's discovery of the Columbia River was later used by the United States to support its claim to the Oregon Country, which was also claimed by Russia, Great Britain, Spain and other nations.{{sfn|Jacobs|1938|p=77}}

In October 1792, Vancouver sent Lieutenant William Robert Broughton, his second-in-command, up the river. Broughton got as far as the Sandy River at the western end of the Columbia River Gorge, about {{convert|100|mi|km}} upstream, sighting and naming Mount Hood. Broughton formally claimed the river, its drainage basin, and the nearby coast for Britain. In contrast, Gray had not made any formal claims on behalf of the United States.{{cite journal |last = Mockford |first = Jim |title = Before Lewis and Clark, Lt. Broughton's River of Names: The Columbia River Exploration of 1792 |jstor = 20615586 |journal = Oregon Historical Quarterly |year = 2005 |volume = 106 |issue = 4 |pages = 542–567 |publisher = Oregon Historical Society |doi = 10.1353/ohq.2005.0011 |s2cid = 165732801 }}{{sfn|Friedman|2003|pp=304–05}}

File:ColyerColumbia76.jpg (oil on canvas). Beacon Rock is visible on the left.]]

File:Lewis and Clark Columbia River.jpg map. The Willamette River is shown as the "Multnomah", while the Snake River is "Lewis's River". (See complete map.)]]

Because the Columbia was at the same latitude as the headwaters of the Missouri River, there was some speculation that Gray and Vancouver had discovered the long-sought Northwest Passage. A 1798 British map showed a dotted line connecting the Columbia with the Missouri.{{sfn|Hayes|1999a}} When the American explorers Meriwether Lewis and William Clark charted the vast, unmapped lands of the American West in their overland expedition (1803–1805), they found no passage between the rivers. After crossing the Rocky Mountains, Lewis and Clark built dugout canoes and paddled down the Snake River, reaching the Columbia near the present-day Tri-Cities, Washington. They explored a few miles upriver, as far as Bateman Island, before heading down the Columbia, concluding their journey at the river's mouth and establishing Fort Clatsop, a short-lived establishment that was occupied for less than three months.{{sfn|Hayes|1999a}}

Canadian explorer David Thompson, of the North West Company, spent the winter of 1807{{ndash}}08 at Kootanae House near the source of the Columbia at present-day Invermere, BC. Over the next few years he explored much of the river and its northern tributaries. In 1811 he traveled down the Columbia to the Pacific Ocean, arriving at the mouth just after John Jacob Astor's Pacific Fur Company had founded Astoria. On his return to the north, Thompson explored the one remaining part of the river he had not yet seen, becoming the first Euro-descended person to travel the entire length of the river.{{sfn|Hayes|1999a}}

In 1825, the Hudson's Bay Company (HBC) established Fort Vancouver on the bank of the Columbia, in what is now Vancouver, Washington, as the headquarters of the company's Columbia District, which encompassed everything west of the Rocky Mountains, north of California, and south of Russian-claimed Alaska. Chief Factor John McLoughlin, a physician who had been in the fur trade since 1804, was appointed superintendent of the Columbia District. The HBC reoriented its Columbia District operations toward the Pacific Ocean via the Columbia, which became the region's main trunk route.{{sfn|Meinig|1995|pp=73–79}} In the early 1840s Americans began to colonize the Oregon country in large numbers via the Oregon Trail, despite the HBC's efforts to discourage American settlement in the region. For many the final leg of the journey involved travel down the lower Columbia River to Fort Vancouver.{{sfn|Mackie|1997|p=318}} This part of the Oregon Trail, the treacherous stretch from The Dalles to below the Cascades, could not be traversed by horses or wagons (only watercraft, at great risk). This prompted the 1846 construction of the Barlow Road.{{cite web |url = http://www.endoftheoregontrail.org/road2oregon/sa21barlowrd.html |title = The Final Leg of the Trail |publisher = End of the Oregon Trail Interpretive Center |archive-url = https://web.archive.org/web/20081012035621/http://www.endoftheoregontrail.org/road2oregon/sa21barlowrd.html |archive-date = October 12, 2008 |url-status = dead }}

In the Treaty of 1818 the United States and Britain agreed that both nations were to enjoy equal rights in Oregon Country for 10 years. By 1828, when the so-called "joint occupation" was renewed indefinitely, it seemed probable that the lower Columbia River would in time become the border between the two nations. For years the Hudson's Bay Company successfully maintained control of the Columbia River and American attempts to gain a foothold were fended off. In the 1830s, American religious missions were established at several locations in the lower Columbia River region. In the 1840s a mass migration of American settlers undermined British control. The Hudson's Bay Company tried to maintain dominance by shifting from the fur trade, which was in decline, to exporting other goods such as salmon and lumber. Colonization schemes were attempted, but failed to match the scale of American settlement. Americans generally settled south of the Columbia, mainly in the Willamette Valley. The Hudson's Bay Company tried to establish settlements north of the river, but nearly all the British colonists moved south to the Willamette Valley. The hope that the British colonists might dilute the American presence in the valley failed in the face of the overwhelming number of American settlers. These developments rekindled the issue of "joint occupation" and the boundary dispute. While some British interests, especially the Hudson's Bay Company, fought for a boundary along the Columbia River, the Oregon Treaty of 1846 set the boundary at the 49th parallel. As part of the treaty, the British retained all areas north of the line while the United States acquired the south. The Columbia River became much of the border between the U.S. territories of Oregon and Washington.{{sfn|Meinig|1995|pp=72–73, 75, 117, 146–47, 169–70}} Oregon became a U.S. state in 1859, while Washington later entered into the Union in 1889.

By the turn of the 20th century, the difficulty of navigating the Columbia was seen as an impediment to the economic development of the Inland Empire region east of the Cascades.{{cite news |last = Reeder |first = Lee B. |title = Open the Columbia to the Sea |publisher = Center for Columbia River History |url = http://www.ccrh.org/comm/umatilla/primary/opensea.htm |access-date = April 3, 2008 |archive-url = https://web.archive.org/web/20160306103837/http://ccrh.org/comm/umatilla/primary/opensea.htm |archive-date = March 6, 2016 |url-status = dead }} URL is to a reprint of a 1902 magazine edition of the Pendleton Daily Tribune published by E. P. Dodd. The dredging and dam building that followed would permanently alter the river, disrupting its natural flow but also providing electricity, irrigation, navigability and other benefits to the region.

{{See also|Steamboats of the Columbia River|Steamboats of the Columbia River, Wenatchee Reach|Shipwrecks of the inland Columbia River}}

File:USACE Astoria-Megler Bridge.jpg; ships must navigate the treacherous Columbia Bar (near horizon, not visible in this picture) to enter or exit the river.]]

File:Steamboat Hassalo running Cascades.jpg runs the Cascades Rapids, May 26, 1888. The rapids are now submerged under the pool of the Bonneville Dam.]]

File:Columbia Log Raft.jpg, containing an entire year's worth of logs from one timber camp, heads downriver in 1906]]

American captain Robert Gray and British captain George Vancouver, who explored the river in 1792, proved that it was possible to cross the Columbia Bar. Many of the challenges associated with that feat remain today; even with modern engineering alterations to the mouth of the river, the strong currents and shifting sandbar make it dangerous to pass between the river and the Pacific Ocean.{{cite web |title = Crossing the Columbia Bar |publisher = Oregon State Marine Board |url = http://www.oregon.gov/OSMB/library/docs/30219_osmb_columbia_bar.pdf |access-date = September 4, 2009 |archive-url = https://web.archive.org/web/20150806235653/http://www.oregon.gov/OSMB/library/docs/30219_osmb_columbia_bar.pdf |url-status = dead |archive-date = August 6, 2015 }}

The use of steamboats along the river, beginning with the British Beaver in 1836{{sfn|Mackie|1997|p=136}} and followed by American vessels in 1850,{{cite news |url = http://www.opb.org/programs/oregonstory/ports/timeline.html |title = The Oregon Story: A Chronology of Ports in Oregon |publisher = Oregon Public Broadcasting |date = January 18, 2007 |access-date = February 15, 2008 |archive-url = https://web.archive.org/web/20080217072330/https://www.opb.org/programs/oregonstory/ports/timeline.html |archive-date = February 17, 2008 |url-status = live }} contributed to the rapid settlement and economic development of the region.{{sfn|Affleck|2000|p=6}}{{sfn|Corning|1977}} Steamboats operated in several distinct stretches of the river: on its lower reaches, from the Pacific Ocean to Cascades Rapids; from the Cascades to the Dalles-Celilo Falls; from Celilo to Priests Rapids; on the Wenatchee Reach of eastern Washington; on British Columbia's Arrow Lakes; and on tributaries like the Willamette, the Snake and Kootenay Lake. The boats, initially powered by burning wood, carried passengers and freight throughout the region for many years. Early railroads served to connect steamboat lines interrupted by waterfalls on the river's lower reaches.{{sfn|Timmen|1972|p=14}} In the 1880s, railroads maintained by companies such as the Oregon Railroad and Navigation Company began to supplement steamboat operations as the major transportation links along the river.{{sfn|Timmen|1972|p=32}}

As early as 1881, industrialists proposed altering the natural channel of the Columbia to improve navigation. Changes to the river over the years have included the construction of jetties at the river's mouth, dredging, and the construction of canals and navigation locks. Today, ocean freighters can travel upriver as far as Portland and Vancouver, and barges can reach as far inland as Lewiston, Idaho.

The shifting Columbia Bar makes passage between the river and the Pacific Ocean difficult and dangerous, and numerous rapids along the river hinder navigation. Pacific Graveyard, a 1964 book by James A. Gibbs, describes the many shipwrecks near the mouth of the Columbia.{{sfn|Gibbs|1964}} Jetties, first constructed in 1886, extend the river's channel into the ocean. Strong currents and the shifting sandbar remain a threat to ships entering the river and necessitate continuous maintenance of the jetties.

In 1891, the Columbia was dredged to enhance shipping. The channel between the ocean and Portland and Vancouver was deepened from {{convert|17|to|25|ft|m}}. The Columbian called for the channel to be deepened to {{convert|40|ft|m}} as early as 1905, but that depth was not attained until 1976.{{cite news |title = Rewind—Editorials from Our Archives: 1905: 40-Ft. Depth Wanted |work = The Columbian |date = December 26, 2005 |url = http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=Rewind--Editorials%20from%20our%20archives:%201905:%2040-ft.%20depth%20wanted&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2005&p_field_advanced-0=&p_text_advanced-0=(Rewind--Editorials%20from%20our%20archives:%201905:%2040-ft.%20depth%20wanted)&p_perpage=10&p_sort=_rank_:DÊl_ranksort=4Êl_useweights=yes |access-date = September 11, 2008 |url-access = subscription |archive-url = https://web.archive.org/web/20191228191901/http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=Rewind--Editorials%20from%20our%20archives:%201905:%2040-ft.%20depth%20wanted&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2005&p_field_advanced-0=&p_text_advanced-0=(Rewind--Editorials%20from%20our%20archives:%201905:%2040-ft.%20depth%20wanted)&p_perpage=10&p_sort=_rank_:D%C3%8Al_ranksort=4%C3%8Al_useweights=yes |archive-date = December 28, 2019 |url-status = live }}

Cascade Locks and Canal were first constructed in 1896 around the Cascades Rapids,The Oregonian, January 1, 1895, p. 8 enabling boats to travel safely through the Columbia River Gorge.{{sfn|Scott|Scott|1924|p=190}} The Celilo Canal, bypassing Celilo Falls, opened to river traffic in 1915.{{cite web |title = The Dalles-Celilo Canal on Columbia River opens to traffic on May 5, 1915 |url = http://www.historylink.org/essays/output.cfm?file_id=5195 |publisher = HistoryLink.org |access-date = November 26, 2007 |archive-url = https://web.archive.org/web/20071116003845/http://www.historylink.org/essays/output.cfm?file_id=5195 |archive-date = November 16, 2007 |url-status = dead }} In the mid-20th century, the construction of dams along the length of the river submerged the rapids beneath a series of reservoirs. An extensive system of locks allowed ships and barges to pass easily between reservoirs. A navigation channel reaching Lewiston, Idaho, along the Columbia and Snake rivers, was completed in 1975. Among the main commodities are wheat and other grains, mainly for export. As of 2016, the Columbia ranked third, behind the Mississippi and Paraná rivers, among the world's largest export corridors for grain.{{cite web |author = U.S. Wheat Associates |title = Overview of Wheat Movement on the Columbia River |url = http://www.pnwa.net/wp-content/uploads/PNWA_Handout.pdf |publisher = Pacific Northwest Waterways Association |year = 2016 |access-date = August 30, 2017 |archive-url = https://web.archive.org/web/20170831045923/http://www.pnwa.net/wp-content/uploads/PNWA_Handout.pdf |archive-date = August 31, 2017 |url-status = live }}

The 1980 eruption of Mount St. Helens caused mudslides in the area, which reduced the Columbia's depth by {{convert|25|ft|m}} for a {{convert|4|mi|km|adj=on}} stretch, disrupting Portland's economy.{{sfn|Harris|1988|p=209}}

File:Essayons.JPG

Efforts to maintain and improve the navigation channel have continued to the present day. In 1990 a new round of studies examined the possibility of further dredging on the lower Columbia. The plans were controversial from the start because of economic and environmental concerns.{{cite news |title = Cleanup Study Already Bogged in Controversy |date = January 21, 1990 |work = The Oregonian |last1 = Koberstein |first1 = Paul |last2 = Durbin |first2 = Kathie }}

In 1999, Congress authorized deepening the channel between Portland and Astoria from {{convert|40|to(-)|43|ft|m}}, which will make it possible for large container and grain ships to reach Portland and Vancouver.{{cite news |title = Dredging Columbia a Very Big Job |work = The Columbian |date = March 7, 2007 |first = Tom |last = Koenninger |access-date = September 11, 2008 |url = http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=Dredging%20Columbia%20a%20very%20big%20job&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2007&p_field_advanced-0=&p_text_advanced-0=(Dredging%20Columbia%20a%20very%20big%20job)&p_perpage=10&p_sort=_rank_:DÊl_ranksort=4Êl_useweights=yes |via = NewsBank |url-access = subscription |archive-url = https://web.archive.org/web/20191224084202/http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=Dredging%20Columbia%20a%20very%20big%20job&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2007&p_field_advanced-0=&p_text_advanced-0=(Dredging%20Columbia%20a%20very%20big%20job)&p_perpage=10&p_sort=_rank_:D%C3%8Al_ranksort=4%C3%8Al_useweights=yes |archive-date = December 24, 2019 |url-status = live }} The project has met opposition because of concerns about stirring up toxic sediment on the riverbed. Portland-based Northwest Environmental Advocates brought a lawsuit against the Army Corps of Engineers, but it was rejected by the Ninth U.S. Circuit Court of Appeals in August 2006.{{cite news |last = Columbian editorial writers |title = In Our View – Monitor the Dredging |work = The Columbian |date = August 26, 2006 |access-date = September 11, 2008 |url = http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=In%20Our%20View%20-%20Monitor%20the%20Dredging&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2006&p_field_advanced-0=&p_text_advanced-0=(In%20Our%20View%20-%20Monitor%20the%20Dredging)&p_perpage=10&p_sort=_rank_:DÊl_ranksort=4Êl_useweights=yes |via = NewsBank |url-access = subscription |archive-url = https://web.archive.org/web/20191223102909/http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=In%20Our%20View%20-%20Monitor%20the%20Dredging&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2006&p_field_advanced-0=&p_text_advanced-0=(In%20Our%20View%20-%20Monitor%20the%20Dredging)&p_perpage=10&p_sort=_rank_:D%C3%8Al_ranksort=4%C3%8Al_useweights=yes |archive-date = December 23, 2019 |url-status = live }} The project includes measures to mitigate environmental damage; for instance, the US Army Corps of Engineers must restore 12 times the area of wetland damaged by the project. In early 2006, the Corps spilled {{convert|50|USgal|L}} of hydraulic oil into the Columbia, drawing further criticism from environmental organizations.{{cite news |title = State Rebukes Corps of Engineers Over Oil Spill |work = The Columbian |date = March 3, 2006 |first = Erik |last = Robinson |access-date = September 11, 2008 |url = http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=State%20rebukes%20Corps%20of%20Engineers%20over%20spill&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2006&p_field_advanced-0=&p_text_advanced-0=(State%20rebukes%20Corps%20of%20Engineers%20over%20spill)&p_perpage=10&p_sort=_rank_:DÊl_ranksort=4Êl_useweights=yes |via = NewsBank |url-access = subscription |archive-url = https://web.archive.org/web/20191221020457/http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=State%20rebukes%20Corps%20of%20Engineers%20over%20spill&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2006&p_field_advanced-0=&p_text_advanced-0=(State%20rebukes%20Corps%20of%20Engineers%20over%20spill)&p_perpage=10&p_sort=_rank_:D%C3%8Al_ranksort=4%C3%8Al_useweights=yes |archive-date = December 21, 2019 |url-status = live }}

Work on the project began in 2005 and concluded in 2010.{{cite web |url = http://www.pnwa.net/new/Articles/Columbia_River_Channel_Deepening.pdf |title = Columbia River Channel Deepening – Maintenance Needed to Maximize Benefits |publisher = Pacific Northwest Waterways Association |access-date = January 23, 2013 |archive-url = https://web.archive.org/web/20130117052830/http://www.pnwa.net/new/Articles/Columbia_River_Channel_Deepening.pdf |archive-date = January 17, 2013 |url-status = dead }} The project's cost is estimated at $150 million. The federal government is paying 65 percent, Oregon and Washington are paying $27 million each, and six local ports are also contributing to the cost.{{cite news |title = Bush Budget Offers $15 Million for Dredging |date = February 8, 2006 |work = The Columbian |access-date = September 11, 2008 |url = http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=Bush%20budget%20offers%20$15%20million%20for%20dredging&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2006&p_field_advanced-0=&p_text_advanced-0=(Bush%20budget%20offers%20$15%20million%20for%20dredging)&p_perpage=10&p_sort=_rank_:DÊl_ranksort=4Êl_useweights=yes |via = NewsBank |url-access = subscription |archive-url = https://web.archive.org/web/20191230173641/http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=Bush%20budget%20offers%20$15%20million%20for%20dredging&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2006&p_field_advanced-0=&p_text_advanced-0=(Bush%20budget%20offers%20$15%20million%20for%20dredging)&p_perpage=10&p_sort=_rank_:D%C3%8Al_ranksort=4%C3%8Al_useweights=yes |archive-date = December 30, 2019 |url-status = live }}

{{See also|Hydroelectric dams on the Columbia River|Columbia River Treaty}}

File:John Day Dam fish ladder.jpg; its reservoir forms the deadliest stretch of the river for young salmon.{{cite news |last=King |first=Anna |date=October 2, 2007 |title=The Modern Day Columbia River – Part Two: Still Waters Run Deep and Deadly for Columbia River Salmon |url=http://news.opb.org/article/still-water-runs-deep-and-deadly-columbia-river-salmon/ |archive-url=https://web.archive.org/web/20160502130146/http://www.opb.org/news/article/still-water-runs-deep-and-deadly-columbia-river-salmon/ |archive-date=May 2, 2016 |access-date=July 17, 2024 |publisher=Oregon Public Broadcasting}}]]

File:ColumbiaRiverRowenaView.jpg and The Dalles, as seen from Rowena Crest]]

File:Kinbasket Lake, Columbia River, British Columbia.jpg

In 1902, the United States Bureau of Reclamation was established to aid in the economic development of arid western states.{{cite web |title = Bureau of Reclamation – About Us |publisher = U.S. Department of the Interior, Bureau of Reclamation |year = 2008 |url = http://www.usbr.gov/main/about/ |access-date = April 3, 2008 |url-status = dead |archive-url = https://web.archive.org/web/20170928181318/https://www.usbr.gov/main/about/ |archive-date = September 28, 2017 |df = mdy-all }} One of its major undertakings was building Grand Coulee Dam to provide irrigation for the {{convert|600|e3acre|km2}} of the Columbia Basin Project in central Washington.{{cite web |title = Grand Coulee Dam |url = http://www.usbr.gov/pn/grandcoulee/ |publisher = U.S. Bureau of Reclamation |year = 2009 |access-date = September 4, 2009 |archive-url = https://web.archive.org/web/20170524040953/http://www.usbr.gov/pn/grandcoulee/ |archive-date = May 24, 2017 |url-status = dead |df = mdy-all }} With the onset of World War II, the focus of dam construction shifted to production of hydroelectricity. Irrigation efforts resumed after the war.

River development occurred within the structure of the 1909 International Boundary Waters Treaty between the United States and Canada. The United States Congress passed the Rivers and Harbors Act of 1925, which directed the U.S. Army Corps of Engineers and the Federal Power Commission to explore the development of the nation's rivers. This prompted agencies to conduct the first formal financial analysis of hydroelectric development; the reports produced by various agencies were presented in House Document 308. Those reports, and subsequent related reports, are referred to as 308 Reports.{{cite web |title = Floods and Flood Control |url = http://www.nwcouncil.org/history/Floods.asp |publisher = Northwest Council |access-date = October 6, 2008 |archive-url = https://web.archive.org/web/20130210064639/http://www.nwcouncil.org/history/Floods.asp |archive-date = February 10, 2013 |url-status = dead }}

The 308 Reports generated 176 publications across the United States.{{Cite web |date=2015 |title=[308 Program]; Pacific Northwest (Oregon, Washington); 308 Program summary |url=https://usace.contentdm.oclc.org/digital/collection/p16021coll5/id/178 |access-date=2024-05-02 |website=U.S. Army Corps of Engineers Digital Library}} Of those 176 documents, thirteen of them were generated in the Pacific Northwest. In 1932, one of the thirteen reports was released on the Columbia River, titled The Columbia River and Minor Tributaries. The report was backed by many engineers and state politicians who believed that the creation of Dams along the Columbia River would be a strong candidate for generation of hydroelectric power. The report led to congressional action, where dams at Bonneville and Grand Coulee were authorized in 1933.

The report itself emphasized the economic values of dam creation. Additionally, the reports emphasized the importance of dams for river navigation. Furthermore, the reports emphasized the importance of hydropower, storage of water for irrigation techniques, and flood control. To ensure that the dams did not affect biodiversity, many engineers and state politicians regarded the importance of salmon within the region. Thus, dams were to be built at a low height that would permit salmon to pass over.{{Cite web |last=Tate |first=Cassandra |date=October 1, 2005 |title=McNary National Wildlife Refuge |url=https://www.historylink.org/File/7493 |access-date=2024-05-02 |website=www.historylink.org}}

In the late 1920s, political forces in the Northwestern United States generally favored the private development of hydroelectric dams along the Columbia. But the overwhelming victories of gubernatorial candidate George W. Joseph in the 1930 Republican primary, and later his law partner Julius Meier, were understood to demonstrate strong public support for public ownership of dams.{{cite journal |title = The Movement for Public Ownership of Power in Oregon |first = Emerson P. |last = Schmidt |journal = The Journal of Land & Public Utility Economics |volume = 7 |date = February 1931 |issue = 1 |pages = 52–60 |jstor = 3138633 |doi = 10.2307/3138633 }} In 1933, President Franklin D. Roosevelt signed a bill that enabled the construction of the Bonneville and Grand Coulee dams as public works projects. The legislation was attributed to the efforts of Oregon Senator Charles McNary, Washington Senator Clarence Dill, and Oregon Congressman Charles Martin, among others.{{cite journal |title = When Dams Weren't Damned: The Public Power Crusade and Visions of the Good Life in the Pacific Northwest in the 1930s |last = Dick |first = Wesley Arden |journal = Environmental Review |volume = 13 |date = Autumn–Winter 1989 |publisher = Forest History Society and American Society for Environmental History |jstor = 3984393 |issue = 3/4 |pages = 113–153 |doi = 10.2307/3984393 |s2cid = 155350722 }}

In 1948, floods swept through the Columbia watershed, destroying Vanport, then the second largest city in Oregon, and impacting cities as far north as Trail, BC.{{cite report |title = Columbia River Treaty: History and 2014/2024 Review |publisher = Bonneville Power Administration and the U.S. Army Corps of Engineers |date = April 2008 |url = http://www.bpa.gov/Corporate/pubs/Columbia_River_Treaty_Review_-_April_2008.pdf |archive-url = https://web.archive.org/web/20120414221348/http://www.bpa.gov/Corporate/pubs/Columbia_River_Treaty_Review_-_April_2008.pdf |archive-date = April 14, 2012 |url-status = dead }} The flooding prompted the U.S. Congress to pass the Flood Control Act of 1950, authorizing the federal development of additional dams and other flood control mechanisms. By that time local communities had become wary of federal hydroelectric projects, and sought local control of new developments; a public utility district in Grant County, Washington, ultimately began construction of the dam at Priest Rapids.{{cite web |title = Priest Rapids Hydroelectric Project No. 2114 Public Utility District No. 2 of Grant County Final Application for New License, Exhibit B: Project Operation and Resource Utilization |date = October 2003 |url = http://www.gcpud.org/pudDocuments/naturalResourcesDocs/disk3/GCPUDFLA3D/contents.pdf |access-date = October 5, 2008 |archive-url = https://web.archive.org/web/20130117052759/http://www.gcpud.org/pudDocuments/naturalResourcesDocs/disk3/GCPUDFLA3D/contents.pdf |archive-date = January 17, 2013 |url-status = dead }}

In the 1960s, the United States and Canada signed the Columbia River Treaty, which focused on flood control and the maximization of downstream power generation. Canada agreed to build dams and provide reservoir storage, and the United States agreed to deliver to Canada one-half of the increase in United States downstream power benefits as estimated five years in advance.{{cite web |title = Treaty Relating to Cooperative Development of the Water Resources of the Columbia River Basin (with Annexes) |publisher = Center for Columbia River History |url = http://www.ccrh.org/comm/river/docs/cotreaty.htm |access-date = September 4, 2009 |archive-url = https://web.archive.org/web/20160405143110/http://www.ccrh.org/comm/river/docs/cotreaty.htm |archive-date = April 5, 2016 |url-status = dead }} Canada's obligation was met by building three dams (two on the Columbia, and one on the Duncan River), the last of which was completed in 1973.{{cite web |title = Dams of the Columbia Basin & Their Effects on the Native Fishery |publisher = Center for Columbia River History |url = http://www.ccrh.org/comm/river/dams9.htm |access-date = September 4, 2009 |archive-url = https://web.archive.org/web/20150915182548/http://www.ccrh.org/comm/river/dams9.htm |archive-date = September 15, 2015 |url-status = dead |df = mdy-all }}

Today the main stem of the Columbia River has fourteen dams, of which three are in Canada and eleven in the United States. Four mainstem dams and four lower Snake River dams contain navigation locks to allow ship and barge passage from the ocean as far as Lewiston, Idaho. The river system as a whole has more than 400 dams for hydroelectricity and irrigation. The dams address a variety of demands, including flood control, navigation, stream flow regulation, storage, and delivery of stored waters, reclamation of public lands and Indian reservations and territories, and the generation of hydroelectric power.{{sfn|Pitzer|1994}}

{{Quote box

| width = 350px

| align = left

| quote = This river may have been shaped by God, or glaciers, or the remnants of the inland sea, or gravity, or a combination of all, but the Army Corps of Engineers controls it now. The Columbia rises and falls, not by the dictates of tide or rainfall, but by a computer-activated, legally arbitrated, federally allocated schedule that changes only when significant litigation is concluded, or a United States Senator nears election time. In that sense, it is reliable.

| source = Timothy Egan, in The Good Rain{{sfn|Egan|1990|p=17}}}}

The larger U.S. dams are owned and operated by the federal government (some by the Army Corps of Engineers and some by the Bureau of Reclamation), while the smaller dams are operated by public utility districts and private power companies. The federally operated system is known as the Federal Columbia River Power System, which includes 31 dams on the Columbia and its tributaries. The system has altered the seasonal flow of the river to meet higher electricity demands during the winter. At the beginning of the 20th century, roughly 75 percent of the Columbia's flow occurred in the summer, between April and September. By 1980, the summer proportion had been lowered to about 50 percent, essentially eliminating the seasonal pattern.{{sfn|National Research Council (U.S.)|2004|pp=4, 22}}

Upon its creation in 1942, the Grand Coulee Dam required land inundation for construction. This flooding included parts of the Colville Reservation and Spokane Reservation. Reservation flooding has resulted in the displacement of 2,250 indigenous peoples located on said reservations.{{Cite journal |last1=Randell |first1=Heather |last2=Curley |first2=Andrew |date=2023-09-01 |title=Dams and tribal land loss in the United States |journal=Environmental research letters: ERL [Web site] |volume=18 |issue=9 |pages=094001 |doi=10.1088/1748-9326/acd268 |issn=1748-9326 |pmid=37564914|pmc=10410305 |bibcode=2023ERL....18i4001R }}

The installation of dams dramatically altered the landscape and ecosystem of the river. At one time, the Columbia was one of the top salmon-producing river systems in the world.{{cite news |last = Rosenberg |first = John |title = Sacred and Shared – Clergy Work to Save Columbia River |work = Christian Century |date = July 19, 2000 }} Previously active fishing sites, such as Celilo Falls in the eastern Columbia River Gorge, have exhibited a sharp decline in fishing along the Columbia in the last century, and salmon populations have been dramatically reduced.{{cite web |title = Celilo Falls and The Dalles Dam Historic Viewer |publisher = Oregon Historical Society |url = http://www.ohs.org/education/oregonhistory/historicviewer/CeliloFalls/ |access-date = September 4, 2009 |archive-url = https://web.archive.org/web/20130117052830/http://www.ohs.org/education/oregonhistory/historicviewer/CeliloFalls/ |archive-date = January 17, 2013 |url-status = dead }} Fish ladders have been installed at some dam sites to help the fish journey to spawning waters. Fish ladders have been seen as highly effective when configurations to fishway exits are properly configured, as reconstructing the Bradford Island fish ladder allowed Sockeye salmon to stray away from spillway zones, reducing fallback (the rate at which fish are found moving away from a dam post-migration) and mortality birthrates. However, improper construction of fish ladders can result in salmon populations exerting significantly more energy when breeding, which results in higher levels of fallback.{{Cite journal |last1=Reischel |first1=Tami S. |last2=Bjornn |first2=Theodore C. |date=November 2003 |title=Influence of Fishway Placement on Fallback of Adult Salmon at the Bonneville Dam on the Columbia River |url=https://onlinelibrary.wiley.com/doi/10.1577/M02-113 |journal=North American Journal of Fisheries Management |language=en |volume=23 |issue=4 |pages=1215–1224 |doi=10.1577/M02-113 |bibcode=2003NAJFM..23.1215R |issn=0275-5947}} Chief Joseph Dam has no fish ladders and completely blocks fish migration to the upper half of the Columbia River system.{{cite web |title = Chief Joseph Dam |url = http://ludb.clui.org/ex/i/WA3264/ |publisher = The Center for Land Use Interpretation |access-date = September 4, 2009 |archive-url = https://web.archive.org/web/20110606120355/http://ludb.clui.org/ex/i/WA3264/ |archive-date = June 6, 2011 |url-status = dead }}

In 2019, both the Yakama and Lummi Northwest Nations proposed to remove the Bonneville, John Day, and The Dalles dams due to their belief removal would strengthen salmon population.{{Cite web |last=Mize |first=Jeffrey |date=October 14, 2019 |title=Two tribes want three Columbia River dams removed |url=https://www.columbian.com/news/2019/oct/14/pacific-northwest-tribes-remove-columbia-river-dams/ |access-date=2024-05-02 |website=The Columbian |language=en-US}} The former Chairman of the Lummi Nation, Jay Julius, stated in 2019 that the fate of salmon without dam removal for the Lummi Nation is a "horrifying reality".{{Cite web |last=Flatt |first=Courtney |date=2019-10-15 |title=Yakama And Lummi Nation Leaders Call For Removal Of 3 Lower Columbia River Dams |url=https://www.nwpb.org/2019/10/14/yakama-and-lummi-nation-leaders-call-for-removal-of-3-lower-columbia-river-dams/ |access-date=2024-05-02 |website=Northwest Public Broadcasting |language=en-US}} JoDe Goudy, a former Chairman of the Yakama Nation, coincides with beliefs of the Lummi Nation, stating "The Columbia River Dams were built on this false legal foundation, and decimated the Yakama Nation’s fisheries, traditional foods, and cultural sites.".{{Cite web |last=Goodykoontz |first=Emily |date=2019-10-15 |title=Tribes call for removal of Bonneville, and other dams, along Columbia River |url=https://www.oregonlive.com/news/2019/10/tribes-call-for-removal-of-bonneville-and-other-dams-along-columbia-river.html |access-date=2024-05-02 |website=oregonlive |language=en}} Both Nations have worked with nonprofit advocacy organizations to further removal agendas.

Throughout 2021, the nonprofit organization Earthjustice represented 10 conservation and fishing organizations in negotiations with President Joe Biden over removal of dam operations on the Snake River. These negotiations culminated in a lawsuit, with Earthjustice requesting to completely halt operations due to their belief of Snake River Dam effects on salmon and steelhead fish runs. On December 15, 2021, the two parties agreed to settle the dispute and focus on a plan to mitigate fish extinction.{{Cite web |last=Baumhardt |first=Alex |date=2023-11-30 |title=Feds consider removing Snake River dams in leaked agreement with plaintiffs in lawsuit • Washington State Standard |url=https://washingtonstatestandard.com/2023/11/30/feds-consider-removing-snake-river-dams-in-leaked-agreement-with-plaintiffs-in-lawsuit/ |access-date=2024-05-02 |website=Washington State Standard |language=en-US}}

Proposed in December 2023, President Joe Biden agreed to a $1 billion mandate, which will attempt to reintroduce Columbia River salmon blockaded by dams. The mandate asked for the Bonneville Power Administration to supply US$300 million over a ten-year span starting in 2024, which includes habitat restoration and upgrades in fish hatcheries. Furthermore, the Biden administration has publicly stated it will examine the possibility of doubling fish and wildlife spending to meet tribal needs. As a benchmark for financial utilization, US$1 billion in backlogged projects have been identified in the Columbia River Basin.{{Cite web |last=Schick |first=Tony |date=December 21, 2023 |title=In a major shift, Northwest tribes — not US officials — will control salmon recovery funds |url=https://www.opb.org/article/2023/12/21/us-grants-tribes-states-control-1-billion-for-salmon-recovery-efforts/ |access-date=2024-05-02 |website=opb |language=en}} The mandate did not call for the removal of four dams on the Snake River.{{Cite web |last=Daly |first=Matthew |date=2024-02-23 |title=White House, tribal leaders hail 'historic' deal to restore salmon runs in Pacific Northwest |url=https://apnews.com/article/salmon-dams-tribes-columbia-snake-river-biden-51408c120a2e2dc147e6b07fe01d3531 |access-date=2024-05-02 |website=AP News |language=en}}

[[File:Columbia dams map.png|thumb|alt=A map shows the locations of many river dams on the Columbia River and its tributaries. They extend from near the river mouth in Oregon and Washington up these rivers into Nevada, Idaho, Wyoming, Montana, and British Columbia.|Prominent dams of the Columbia River Basin. Color indicates dam ownership: {{legend|#C500FF|US Federal government}}

{{legend|#E60000|Public utilities}}

{{legend|#4CE600|State, provincial, or local government}}

{{legend|#A87000|Private}}]]

The Bureau of Reclamation's Columbia Basin Project focused on the generally dry region of central Washington known as the Columbia Basin, which features rich loess soil. Several groups developed competing proposals, and in 1933, President Franklin D. Roosevelt authorized the Columbia Basin Project. The Grand Coulee Dam was the project's central component; upon completion, it pumped water up from the Columbia to fill the formerly dry Grand Coulee, forming Banks Lake. By 1935, the intended height of the dam was increased from a range between {{convert|200|and|300|ft|m}} to {{convert|500|ft|m}}, a height that would extend the lake impounded by the dam to the Canada–United States border; the project had grown from a local New Deal relief measure to a major national project.{{sfn|Pitzer|1994}}

The project's initial purpose was irrigation, but the onset of World War II created a high electricity demand, mainly for aluminum production and for the development of nuclear weapons at the Hanford Site. Irrigation began in 1951.{{cite book |title = Lake Roosevelt, Administrative History |publisher = U.S. National Park Service: Department of the Interior |chapter-url = https://www.nps.gov/history/history/online_books/laro/adhi/adhit.htm |archive-url = https://web.archive.org/web/20070716185155/https://www.nps.gov/history/history/online_books/laro/adhi/adhit.htm |archive-date = July 16, 2007 |chapter = Chapter 2 }} The project provides water to more than {{convert|670|e3acre|km2|abbr=off|sp=us}} of fertile but arid land in central Washington, transforming the region into a major agricultural center. Important crops include orchard fruit, potatoes, alfalfa, mint, beans, beets, and wine grapes.

Since 1750, the Columbia has experienced six multi-year droughts. The longest, lasting 12 years in the mid‑19th century, reduced the river's flow to 20 percent below average. Scientists have expressed concern that a similar drought would have grave consequences in a region so dependent on the Columbia.{{cite web |last1 = Hines |first1 = Sandra |last2 = Sands |first2 = Yasmeen |last3 = Hunt |first3 = Lori Bona |publisher = University of Washington Office of News and Information |title = Tree-Ring Data Reveals Multiyear Droughts Unlike Any in Recent Memory |date = February 14, 2005 |url = http://www.washington.edu/news/archive/id/8220 |access-date = January 26, 2008 |archive-url = https://web.archive.org/web/20121010133118/http://www.washington.edu/news/archive/id/8220 |archive-date = October 10, 2012 |url-status = live }} In 1992–1993, a lesser drought affected farmers, hydroelectric power producers, shippers, and wildlife managers.

Many farmers in central Washington build dams on their property for irrigation and to control frost on their crops. The Washington Department of Ecology, using new techniques involving aerial photographs, estimated there may be as many as a hundred such dams in the area, most of which are illegal. Six such dams have failed in recent years, causing hundreds of thousands of dollars of damage to crops and public roads. Fourteen farms in the area have gone through the permitting process to build such dams legally.{{cite news |last = McNiel |first = Michelle |title = State Cracking Down on Illegal Frost-Control Dams |date = March 21, 2008 |work = Wenatchee World }}

The Columbia's heavy flow and large elevation drop over a short distance, {{convert|2.16|ft/mi|abbr=off|sp=us}}, give it tremendous capacity for hydroelectricity generation. In comparison, the Mississippi drops less than {{convert|0.65|ft/mi}}. The Columbia alone possesses one-third of the United States's hydroelectric potential.{{sfn|Harden|1996|p=17}} In 2012, the river and its tributaries accounted for 29 GW of hydroelectric generating capacity, contributing 44 percent of the total hydroelectric generation in the nation.{{cite web |url = https://www.eia.gov/todayinenergy/detail.cfm?id=16891 |last = Lillis |first = Kevin |title = The Columbia River Basin Provides More Than 40% of Total U.S. Hydroelectric Generation |date = June 27, 2014 |access-date = June 1, 2016 |publisher = U.S. Energy Information Agency |archive-url = https://web.archive.org/web/20170609095801/https://www.eia.gov/todayinenergy/detail.php?id=16891 |archive-date = June 9, 2017 |url-status = live }}

[[File:Woody Guthrie NYWTS.jpg|thumb|left|upright|alt=Half-length photo of a middle-aged man sitting in front of a closed door and playing a guitar and singing. His wavy black hair is partly covered by a black hat tipped at a rakish angle. He wears a striped flannel work shirt. His black guitar has a sign on it that says, "This machine kills fascists".|Roll on, Columbia, roll on, roll on, Columbia, roll on / Your power is turning our darkness to dawn / Roll on, Columbia, roll on.

Lyrics from Woody Guthrie's 1941 song Roll on Columbia, written for the Bonneville Power Administration.

]]

The largest of the 150 hydroelectric projects, the Grand Coulee Dam and Chief Joseph Dam are also the largest in the United States.{{cite web |title = Renewable Energy Explained |url = https://www.eia.gov/energyexplained/index.cfm?page=renewable_home#tab2 |publisher = US Energy Information Administration |year = 2017 |access-date = May 9, 2017 |archive-url = https://web.archive.org/web/20170611123322/https://www.eia.gov/energyexplained/index.cfm?page=renewable_home |archive-date = June 11, 2017 |url-status = live }}{{cite web |title = Chief Joseph Dam and Rufus Woods Lake |publisher = U.S. Army Corps of Engineers |date = November 19, 2003 |url = http://www.nwd-wc.usace.army.mil/report/chj.htm |access-date = April 3, 2008 |archive-url = https://web.archive.org/web/20130301183103/http://www.nwd-wc.usace.army.mil/report/chj.htm |archive-date = March 1, 2013 |url-status = dead }} As of 2017, Grand Coulee is the fifth largest hydroelectric plant in the world.{{cite web |title = Three Gorges Dam: The World's Largest Hydroelectric Plant |url = https://water.usgs.gov/edu/hybiggest.html |publisher = US Geological Survey |year = 2017 |access-date = May 9, 2017 |archive-url = https://web.archive.org/web/20170624222141/https://water.usgs.gov/edu/hybiggest.html |archive-date = June 24, 2017 |url-status = live }}

Inexpensive hydropower supported the location of a large aluminum industry in the region because its reduction from bauxite requires large amounts of electricity. Until 2000, the Northwestern United States produced up to 17 percent of the world's aluminum and 40 percent of the aluminum produced in the United States.{{cite news |title = Aluminum Industry Powering Down |last = Kinsey Hill |first = Gail |date = March 11, 2001 |work = The Oregonian }} The commoditization of power in the early 21st century, coupled with a drought that reduced the generation capacity of the river, damaged the industry and by 2001, Columbia River aluminum producers had idled 80 percent of its production capacity. By 2003, the entire United States produced only 15 percent of the world's aluminum and many smelters along the Columbia had gone dormant or out of business.{{cite news |first = Gretchen |last = Fehrenbacher |title = Aluminum All But Gone |date = February 23, 2003 |work = The Columbian |access-date = September 11, 2008 |page = E1 |url = http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=Aluminum%20all%20but%20gone&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2003&p_field_advanced-0=&p_text_advanced-0=(Aluminum%20all%20but%20gone)Êl_numdocs=20&p_perpage=10&p_sort=_rank_:DÊl_ranksort=4Êl_useweights=yes |via = Newsbank |url-access = subscription |archive-url = https://web.archive.org/web/20191223194644/http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=Aluminum%20all%20but%20gone&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2003&p_field_advanced-0=&p_text_advanced-0=(Aluminum%20all%20but%20gone)%C3%8Al_numdocs=20&p_perpage=10&p_sort=_rank_:D%C3%8Al_ranksort=4%C3%8Al_useweights=yes |archive-date = December 23, 2019 |url-status = live }}{{cite news |title = BPA Chief to Detail Strategy for Troubled Power Broker |first = William |last = McCall |date = November 22, 2002 |work = The Columbian |access-date = September 12, 2008 |page = C2 |url = http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=BPA%20chief%20to%20detail%20strategy%20for%20troubled%20power%20broker&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2002&p_field_advanced-0=&p_text_advanced-0=(BPA%20chief%20to%20detail%20strategy%20for%20troubled%20power%20broker)Êl_numdocs=20&p_perpage=10&p_sort=_rank_:DÊl_ranksort=4Êl_useweights=yes |via = Newsbank |url-access = subscription |archive-url = https://web.archive.org/web/20191222170950/http://nl.newsbank.com/nl-search/we/Archives?p_product=VC&p_theme=vc&p_action=search&p_maxdocs=200&s_dispstring=BPA%20chief%20to%20detail%20strategy%20for%20troubled%20power%20broker&p_field_date-0=YMD_date&p_params_date-0=date:B,E&p_text_date-0=2002&p_field_advanced-0=&p_text_advanced-0=(BPA%20chief%20to%20detail%20strategy%20for%20troubled%20power%20broker)%C3%8Al_numdocs=20&p_perpage=10&p_sort=_rank_:D%C3%8Al_ranksort=4%C3%8Al_useweights=yes |archive-date = December 22, 2019 |url-status = live }}

Power remains relatively inexpensive along the Columbia, and since the mid-2000 several global enterprises have moved server farm operations into the area to avail themselves of cheap power.{{cite news |title = Hiding in Plain Sight, Google Seeks More Power |work = The New York Times |date = June 14, 2006 |last1 = Markoff |first1 = John |last2 = Hansell |first2 = Saul |access-date = September 11, 2008 |url = https://www.nytimes.com/2006/06/14/technology/14search.html |archive-url = https://web.archive.org/web/20080406111310/http://www.nytimes.com/2006/06/14/technology/14search.html |archive-date = April 6, 2008 |url-status = live }}{{cite journal |last = Mehta |first = Stephanie N. |title = Behold the Server Farm! Glorious Temple of the Information Age! |journal = Fortune |date = August 7, 2006 |url = https://money.cnn.com/magazines/fortune/fortune_archive/2006/08/07/8382587/index.htm |access-date = April 4, 2008 |archive-url = https://web.archive.org/web/20150612111208/http://archive.fortune.com/magazines/fortune/fortune_archive/2006/08/07/8382587/index.htm |archive-date = June 12, 2015 |url-status = live }}{{Cite news |url = https://www.politico.eu/article/this-is-what-happens-when-bitcoin-miners-take-over-your-town/ |title = This is what happens when bitcoin miners take over your town |date = March 9, 2018 |work = POLITICO |access-date = March 15, 2018 |language = en-US |archive-url = https://web.archive.org/web/20180315200040/https://www.politico.eu/article/this-is-what-happens-when-bitcoin-miners-take-over-your-town/ |archive-date = March 15, 2018 |url-status = live }} Downriver of Grand Coulee, each dam's reservoir is closely regulated by the Bonneville Power Administration (BPA), the U.S. Army Corps of Engineers, and various Washington public utility districts to ensure flow, flood control, and power generation objectives are met. Increasingly, hydro-power operations are required to meet standards under the U.S. Endangered Species Act and other agreements to manage operations to minimize impacts on salmon and other fish, and some conservation and fishing groups support removing four dams on the lower Snake River, the largest tributary of the Columbia.{{cite news |first = Michael |last = Milstein |title = Judge Rips Latest Plan to Help Salmon |date = December 11, 2007 |work = The Oregonian }}

In 1941, the BPA hired Oklahoma folksinger Woody Guthrie to write songs for a documentary film{{cite video |year = 1949 |title = Video: The Columbia (1949) |url = https://archive.org/details/gov.fdr.353.3.4 |publisher = United States Department of the Interior |access-date = February 22, 2012 |archive-url = https://web.archive.org/web/20120627204353/https://archive.org/details/gov.fdr.353.3.4 |archive-date = June 27, 2012 |url-status = live }} promoting the benefits of hydropower. In the month he spent traveling the region Guthrie wrote 26 songs, which have become an important part of the cultural history of the region.{{cite news |title = Rolling Along the Columbia, Driving for Woody Guthrie |date = July 8, 2007 |first = Spencer |last = Heinz |work = The Oregonian }}{{cite magazine |title = This Land Is Whose Land? |magazine = Time |date = July 8, 2002 |first1 = Lance |last1 = Morrow |first2 = Nathan |last2 = Thornburgh |access-date = April 4, 2008 |url = http://www.time.com/time/magazine/article/0,9171,1002825,00.html |url-access = subscription |archive-url = https://web.archive.org/web/20071016190137/http://www.time.com/time/magazine/article/0,9171,1002825,00.html |archive-date = October 16, 2007 |url-status = dead }}

{{clear}}

{{See also|Environmental impact of reservoirs}}

File:Seining salmon.jpg salmon on the Columbia River, 1914]]

File:Dead salmon in spawning season.jpg in Oregon, November 2007.]]

The Columbia supports several species of anadromous fish that migrate between the Pacific Ocean and freshwater tributaries of the river. Sockeye salmon, Coho and Chinook ("king") salmon, and steelhead, all of the genus Oncorhynchus, are ocean fish that migrate up the rivers at the end of their life cycles to spawn.{{cite web |title = Salmon and Steelhead |publisher = Bonneville Power Administration |url = https://www.bpa.gov/efw/FishWildlife/SalmonSteelhead/Pages/default.aspx |access-date = July 1, 2017 |archive-url = https://web.archive.org/web/20170510210922/https://www.bpa.gov/efw/FishWildlife/SalmonSteelhead/Pages/default.aspx |archive-date = May 10, 2017 |url-status = live }} White sturgeon, which take 15 to 25 years to mature, typically migrate between the ocean and the upstream habitat several times during their lives.{{cite web |title = White Sturgeon |url = http://www.psmfc.org/habitat/edu_wsturg_fact.html |publisher = Pacific Coast Marine Habitat Program |year = 1996 |access-date = September 4, 2009 |archive-url = https://web.archive.org/web/20160303180521/http://www.psmfc.org/habitat/edu_wsturg_fact.html |archive-date = March 3, 2016 |url-status = dead }}

Salmon populations declined dramatically after the establishment of canneries in 1867. In 1879 it was reported that 545,450 salmon, with an average weight of {{convert|22|lb|kg}} were caught (in a recent season) and mainly canned for export to England. A can weighing {{convert|1|lb|kg}} could be sold for 8d or 9d.{{cite news |title = Editorial |work = The Cornishman |issue = 75 |date = December 18, 1879 |page = 4 }} By 1908, there was widespread concern about the decline of salmon and sturgeon. In that year, the people of Oregon passed two laws under their newly instituted program of citizens' initiatives limiting fishing on the Columbia and other rivers.{{sfn|Benson|1908|pp=44–57}} Then in 1948, another initiative banned the use of seine nets (devices already used by Native Americans, and refined by later settlers) altogether.{{cite encyclopedia |last = Smith |first = Courtland L. |title = Seine Fishing |url = http://www.oregonencyclopedia.org/articles/seine_fishing/ |encyclopedia = The Oregon Encyclopedia |publisher = Portland State University and the Oregon Historical Society |date = April 17, 2016 |access-date = June 19, 2017 |archive-url = https://web.archive.org/web/20170621011309/https://oregonencyclopedia.org/articles/seine_fishing/ |archive-date = June 21, 2017 |url-status = live }}

Dams interrupt the migration of anadromous fish. Salmon and steelhead return to the streams in which they were born to spawn; where dams prevent their return, entire populations of salmon die. Some of the Columbia and Snake River dams employ fish ladders, which are effective to varying degrees at allowing these fish to travel upstream. Another problem exists for the juvenile salmon headed downstream to the ocean. Previously, this journey would have taken two to three weeks. With river currents slowed by the dams, and the Columbia converted from a wild river to a series of slackwater pools, the journey can take several months, which increases the mortality rate.{{sfn|Mueller|1997|p=229}} In some cases, the Army Corps of Engineers transports juvenile fish downstream by truck or river barge. The Chief Joseph Dam and several dams on the Columbia's tributaries entirely block migration, and there are no migrating fish on the river above these dams. Sturgeons have different migration habits and can survive without ever visiting the ocean. In many upstream areas cut off from the ocean by dams, sturgeon simply live upstream of the dam.{{cite web |title = Upper Columbia White Sturgeon |url = http://www.uppercolumbiasturgeon.org/ |publisher = Upper Columbia White Sturgeon Recovery Initiative |year = 2007 |access-date = September 4, 2009 |archive-url = https://web.archive.org/web/20170611145152/http://www.uppercolumbiasturgeon.org/ |archive-date = June 11, 2017 |url-status = dead }}

Not all fish have suffered from the modifications to the river; the northern pikeminnow (formerly known as the squawfish) thrives in the warmer, slower water created by the dams. Research in the mid-1980s found that juvenile salmon were suffering substantially from the predatory pikeminnow,{{cite web |title = The Northern Pikeminnow Management Program |url = http://www.dfw.state.or.us/fish/OSCRP/CRI/Pikeminnow.asp |publisher = Oregon Department of Fish and Wildlife |date = August 25, 2008 |access-date = September 20, 2009 |archive-url = https://web.archive.org/web/20170109030133/http://www.dfw.state.or.us/fish/OSCRP/CRI/Pikeminnow.asp |archive-date = January 9, 2017 |url-status = dead }} and in 1990, in the interest of protecting salmon, a "bounty" program was established to reward anglers for catching pikeminnow.{{cite news |title = Fishing for Dollars |first = Chris |last = Hansen |work = The Register-Guard |date = July 7, 2005 }}

In 1994, the salmon catch was smaller than usual in the rivers of Oregon, Washington, and British Columbia, causing concern among commercial fishermen, government agencies, and tribal leaders.{{cite news |first = John |last = Balzar |title = As Wild Salmon Fade, Northwest Losing a Symbol |work = Los Angeles Times |date = April 2, 1994 |url = https://pqasb.pqarchiver.com/latimes/access/59341587.html?dids=59341587:59341587&FMT=ABS&FMTS=ABS:FT&date=Apr+02%2C+1994&author=JOHN+BALZAR&pub=Los+Angeles+Times+(pre-1997+Fulltext)&desc=As+Wild+Salmon+Fade%2C+Northwest+Losing+a+Symbol&pqatl=google |access-date = March 19, 2008 |url-access = subscription |archive-url = https://web.archive.org/web/20111229151256/http://pqasb.pqarchiver.com/latimes/access/59341587.html?dids=59341587:59341587&FMT=ABS&FMTS=ABS:FT&date=Apr+02%2C+1994&author=JOHN+BALZAR&pub=Los+Angeles+Times+(pre-1997+Fulltext)&desc=As+Wild+Salmon+Fade%2C+Northwest+Losing+a+Symbol&pqatl=google |archive-date = December 29, 2011 |url-status = dead }}{{cite news |last=Swardson |first=Anne |date=December 30, 1994 |title=Mystery of Vanishing Salmon Puzzles Canadians; Commercial Fishermen, Indian Groups and Officials Dispute Who's to Blame for Drop in Harvest |url=https://www.washingtonpost.com/archive/politics/1994/12/31/mystery-of-vanishing-salmon-puzzles-canadians/34afafba-03ac-4b76-8236-3a2d3372f8f1/ |access-date= |newspaper=}} US government intervention, to which the states of Alaska, Idaho, and Oregon objected, included an 11-day closure of an Alaska fishery.{{cite news |title = Lawsuit Targets Fishery Closure: Alaska Seeks to Reverse Policy on Snake River King Salmon Run |first = Marilee |last = Enge |date = March 3, 1994 |work = Anchorage Daily News |format = subscription required |url = http://nl.newsbank.com/nl-search/we/Archives?p_product=AS&p_theme=as&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0F78EC32E9B37EDB&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM |access-date = March 19, 2008 |archive-url = https://web.archive.org/web/20121017142551/http://nl.newsbank.com/nl-search/we/Archives?p_product=AS&p_theme=as&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0F78EC32E9B37EDB&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM |archive-date = October 17, 2012 |url-status = live }} In April 1994 the Pacific Fisheries Management Council unanimously approved the strictest regulations in 18 years, banning all commercial salmon fishing for that year from Cape Falcon north to the Canada–US border.{{cite news |title = Strict Fishing Limits Are Passed to Protect Salmon in Northwest |date = April 10, 1994 |url = https://query.nytimes.com/gst/fullpage.html?res=9C01EEDD153EF933A25757C0A962958260 |work = The New York Times |access-date = March 19, 2008 }} In the winter of 1994, the return of coho salmon far exceeded expectations, which was attributed in part to the fishing ban.{{cite news |title = Massive Coho Return Surprises Fisheries |work = The News Tribune |date = December 28, 1994 |url-access = subscription |url = http://nl.newsbank.com/nl-search/we/Archives?p_product=NewsLibrary&p_multi=TNTB&d_place=TNTB&p_theme=newslibrary2&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0F0FBF58EE18B3C4&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM |access-date = March 19, 2008 |archive-url = https://web.archive.org/web/20121017142627/http://nl.newsbank.com/nl-search/we/Archives?p_product=NewsLibrary&p_multi=TNTB&d_place=TNTB&p_theme=newslibrary2&p_action=search&p_maxdocs=200&p_topdoc=1&p_text_direct-0=0F0FBF58EE18B3C4&p_field_direct-0=document_id&p_perpage=10&p_sort=YMD_date:D&s_trackval=GooglePM |archive-date = October 17, 2012 |url-status = live }}

Also in 1994, United States Secretary of the Interior Bruce Babbitt proposed the removal of several Pacific Northwest dams because of their impact on salmon spawning.{{cite news |title = Are West's Dams Set in Stone? Bruce Babbitt Dreams of Razing Some of Them to Transform Rivers and the Interior Department. But Businesses Dependent on Cheap Water and Power Fear the Added Expense and Predict Job Losses |work = Los Angeles Times |first = Melissa |last = Healy |date = March 31, 1994 |url = https://pqasb.pqarchiver.com/latimes/access/59340985.html?dids=59340985:59340985&FMT=ABS&FMTS=ABS:FT&date=Mar+31%2C+1994&author=MELISSA+HEALY&pub=Los+Angeles+Times+(pre-1997+Fulltext)&desc=COLUMN+ONE+Are+West's+Dams+Set+in+Stone%3F+Bruce+Babbitt+dreams+of+razing+some+of+them+to+transform+rivers+and+the+Interior+Department.+But+businesses+dependent+on+cheap+water+and+power+fear+the+added+expense+and+predict+job+losses.&pqatl=google |access-date = March 19, 2008 |archive-url = https://web.archive.org/web/20111229141339/http://pqasb.pqarchiver.com/latimes/access/59340985.html?dids=59340985%3A59340985&FMT=ABS&FMTS=ABS%3AFT&date=Mar+31%2C+1994&author=MELISSA+HEALY&pub=Los+Angeles+Times+%28pre-1997+Fulltext%29&desc=COLUMN+ONE+Are+West%27s+Dams+Set+in+Stone%3F+Bruce+Babbitt+dreams+of+razing+some+of+them+to+transform+rivers+and+the+Interior+Department.+But+businesses+dependent+on+cheap+water+and+power+fear+the+added+expense+and+predict+job+losses.&pqatl=google |archive-date = December 29, 2011 |url-status = dead }} The Northwest Power Planning Council approved a plan that provided more water for fish and less for electricity, irrigation, and transportation.{{cite news |last=Power Planning Council |first=Northwest |date=December 14, 1994 |title=1994 Columbia River Basin Fish and Wildlife Program |url=https://www.nwcouncil.org/sites/default/files/program_19.pdf}} Environmental advocates have called for the removal of certain dams in the Columbia system in the years since. Of the 227 major dams in the Columbia River drainage basin, the four Washington dams on the lower Snake River are often identified for removal,{{cite news |title = Pressure Builds on Snake River Dams |first = Erik |last = Robinson |work = The Columbian |access-date = April 4, 2008 |url = http://www.bluefish.org/pressure.htm |date = April 15, 2007 |archive-url = https://web.archive.org/web/20090815062935/http://www.bluefish.org/pressure.htm |archive-date = August 15, 2009 |url-status = live }} for example in an ongoing lawsuit concerning a Bush administration plan for salmon recovery. These dams and reservoirs limit the recovery of upriver salmon runs to Idaho's Salmon and Clearwater rivers.{{cite news |title = Oregon's Delicate Balance |date = September 11, 2006 |first = Bill |last = Monroe |work = The Oregonian }} Historically, the Snake produced over 1.5 million spring and summer Chinook salmon, a number that has dwindled to several thousand in recent years.{{cite news |title = Court Finds Feds No Help to Fish |first = Michael |last = Milstein |work = The Oregonian |date = April 10, 2007 }} Idaho Power Company's Hells Canyon dams have no fish ladders (and do not pass juvenile salmon downstream), and thus allow no steelhead or salmon to migrate above Hells Canyon. In 2007, the destruction of the Marmot Dam on the Sandy River was the first dam removal in the system.{{cite news |author = Oregonian editorial writers |title = A River Released to the Wild |work = The Oregonian |date = July 29, 2007 }} Other Columbia Basin dams that have been removed include Condit Dam on Washington's White Salmon River, and the Milltown Dam on the Clark Fork in Montana.{{cite web |title = Clark Fork to Flow Free This Month |date = March 14, 2008 |first = Kevin |last = Colburn |publisher = AmericanWhitewater.org |url = http://www.americanwhitewater.org/content/Article_view_display_full_id_29971_ |access-date = March 28, 2008 |archive-url = https://web.archive.org/web/20110617021353/http://www.americanwhitewater.org/content/Article_view_display_full_id_29971_ |archive-date = June 17, 2011 |url-status = dead |df = mdy-all }}

In southeastern Washington, a {{convert|50|mi|km|adj=on}} stretch of the river passes through the Hanford Site, established in 1943 as part of the Manhattan Project. The site served as a plutonium production complex, with nine nuclear reactors and related facilities along the banks of the river. From 1944 to 1971, pump systems drew cooling water from the river and, after treating this water for use by the reactors, returned it to the river. Before being released back into the river, the used water was held in large tanks known as retention basins for up to six hours. Longer-lived isotopes were not affected by this retention, and several terabecquerels entered the river every day. By 1957, the eight plutonium production reactors at Hanford dumped a daily average of 50,000 curies of radioactive material into the Columbia.{{cite web |last = Washington Physicians for Social Responsibility |title = Hanford History |year = 2007 |url = http://www.psr.org/chapters/washington/hanford/hanford-history.html |access-date = April 4, 2008 |archive-url = https://web.archive.org/web/20170619003042/http://www.psr.org/chapters/washington/hanford/hanford-history.html |archive-date = June 19, 2017 |url-status = dead |df = mdy-all }} These releases were kept secret by the federal government until the release of declassified documents in the late 1980s.{{cite web |author = Hanford Health Information Network |year = 2000 |title = An Overview of Hanford and Radiation Health Effects |url = http://www.doh.wa.gov/hanford/publications/overview/overview.html |archive-url = https://web.archive.org/web/20100823040735/http://www.doh.wa.gov/hanford/publications/overview/overview.html |archive-date = August 23, 2010 }} Radiation was measured downstream as far west as the Washington and Oregon coasts.{{cite news |title = Radiation Flowed 200 Miles to Sea, Study Finds |work = The New York Times |url = https://query.nytimes.com/gst/fullpage.html?res=9E0CE0D8173FF934A25754C0A964958260 |date = July 17, 1992 |access-date = January 29, 2007 |archive-url = https://web.archive.org/web/20080610175545/http://query.nytimes.com/gst/fullpage.html?res=9E0CE0D8173FF934A25754C0A964958260 |archive-date = June 10, 2008 |url-status = live }}

File:Hanford N Reactor adjusted.jpg along the river]]

The nuclear reactors were decommissioned at the end of the Cold War, and the Hanford site is the focus of one of the world's largest environmental cleanup, managed by the Department of Energy under the oversight of the Washington Department of Ecology and the Environmental Protection Agency.{{cite web |last = U.S. Department of Energy |author-link = United States Department of Energy |title = Hanford Site |year = 2015 |url = http://energy.gov/em/hanford-site |access-date = September 30, 2015 |archive-url = https://web.archive.org/web/20151001090714/http://energy.gov/em/hanford-site |archive-date = October 1, 2015 |url-status = live }} Nearby aquifers contain an estimated 270 billion US gallons (1 billion m³) of groundwater contaminated by high-level nuclear waste that has leaked out of Hanford's underground storage tanks.{{cite news |last = Wolman |first = David |title = Fission Trip |work = Wired Magazine |date = April 2007 |page = 78 }} {{As of|2008}}, 1 million US gallons (3,785 m³) of highly radioactive waste is traveling through groundwater toward the Columbia River. This waste is expected to reach the river in 12 to 50 years if cleanup does not proceed on schedule.{{cite web |last = Washington Department of Ecology |author-link = Washington Department of Ecology |title = Hanford Quick Facts |url = http://www.ecy.wa.gov/features/hanford/hanfordfacts.html |archive-url = https://web.archive.org/web/20070812061411/http://www.ecy.wa.gov/features/hanford/hanfordfacts.html |archive-date = August 12, 2007 }}

In addition to concerns about nuclear waste, numerous other pollutants are found in the river. These include chemical pesticides, bacteria, arsenic, dioxins, and polychlorinated biphenyls (PCB).{{cite news |title = Activist Plans an Epic Swim |first = Ben |last = Jacklet |work = The Portland Tribune |date = July 24, 2001 |url = http://www.portlandtribune.com/news/story.php?story_id=5243 |access-date = September 16, 2008 |archive-url = https://web.archive.org/web/20110608041803/http://www.portlandtribune.com/news/story.php?story_id=5243 |archive-date = June 8, 2011 |url-status = dead }}

Studies have also found significant levels of toxins in fish and the waters they inhabit within the basin. Accumulation of toxins in fish threatens the survival of fish species, and human consumption of these fish can lead to health problems. Water quality is also an important factor in the survival of other wildlife and plants that grow in the Columbia River drainage basin. The states, indigenous tribes, and federal government are all engaged in efforts to restore and improve the water, land, and air quality of the Columbia River drainage basin and have committed to work together to accomplish critical ecosystem restoration efforts. Several cleanup efforts are underway, including Superfund projects at Portland Harbor, Hanford, and Lake Roosevelt.{{cite web |last = U.S. Environmental Protection Agency |title = Columbia River Basin: A National Priority |year = 2008 |url = http://yosemite.epa.gov/r10/ecocomm.nsf/Columbia/Columbia |access-date = April 4, 2008 |archive-url = https://web.archive.org/web/20061028070047/http://yosemite.epa.gov/r10/ecocomm.nsf/Columbia/Columbia |archive-date = October 28, 2006 |url-status = dead }}

In early 2022, thousands of protestors demonstrated a demand for heightened cleanup efforts within the Hanford Nuclear Site. In June 2022, nearly 200 protestors attended the Hanford Journey Event, an educational tour which allowed those concerned about the Hanford Nuclear Site to learn about proposed cleanup efforts.The Hanford Journey Event was co-sponsored by the Yakama Nation. Davis Washines, a representative from the Yakama Nation Department of Natural Resources, alluded to "[the Hanford cleanup] has a lot of meaning to us, to our people. And not just for us, our personal safety, but to this ground, to the water, because they were here before we were".{{Cite web |last=PETTINGILL |first=REBECCA |date=2022-06-29 |title=Hope for Hanford |url=https://columbiabasinherald.com/news/2022/jun/29/hope-hanford/ |access-date=2024-05-02 |website=Columbia Basin Herald |language=en}} Congress responded in 2022 by increasing the budget for the Hanford clean-up efforts, after thousands of comments were sent to federal authorities to prevent high-level waste storage at Hanford.{{Cite web |last=Serres |first=Dan |date=February 13, 2023 |title=Standing Up For Clean Up At Hanford |url=https://www.columbiariverkeeper.org/news/2023/2/standing-cleanup-hanford |access-date=2024-05-02 |website=www.columbiariverkeeper.org}}

Starting between April and June 2025, the Hanford Nuclear Site is expected to melt radioactive wastes combined with glass flakes at a rate of 21 metric tons per day.  The melters being utilized have a lifespan of five years, which requires their replacement in 2030. As of 2023, the Hanford site cleanup project is sixteen years behind schedule. One of the harmful chemicals located in the Hanford site, strontium-90, reached over 2,000 times the standard concentration for drinking water in August 2022.{{Cite web |last=Stang |first=John |date=December 5, 2023 |title=At long last, Hanford poised to clean up nuclear waste with glass {{!}} Cascade PBS News |url=https://crosscut.com/briefs/2023/12/long-last-hanford-poised-clean-nuclear-waste-glass |access-date=2024-05-02 |website=crosscut.com |language=en}}

Timber industry activity further contaminates river water, for example in the increased sediment runoff that results from clearcuts. The Northwest Forest Plan, a piece of federal legislation from 1994, mandated that timber companies consider the environmental impacts of their practices on rivers like the Columbia.{{cite news |title = Bush Change to NW Forest Plan Would Ease Logging |first = J.R. |last = Pegg |date = November 26, 2007 |work = Environment News Service |url = http://www.ens-newswire.com/ens/nov2002/2002-11-26-10.asp |access-date = April 1, 2008 |archive-url = https://web.archive.org/web/20080517002243/http://www.ens-newswire.com/ens/nov2002/2002-11-26-10.asp |archive-date = May 17, 2008 |url-status = live }}

On July 1, 2003, Christopher Swain became the first person to swim the Columbia River's entire length, to raise public awareness about the river's environmental health.{{cite news |title = Swimming to Astoria |first = Patty |last = Wentz |date = May 29, 2002 |work = Willamette Week |url = http://www.wweek.com/portland/article-1048-swimming_to_astoria.html |access-date = November 22, 2007 |archive-url = https://web.archive.org/web/20160303222821/http://www.wweek.com/portland/article-1048-swimming_to_astoria.html |archive-date = March 3, 2016 |url-status = dead }}{{cite news |title = Challenge Sets Off Global Ripples |first = Jennifer |last = Anderson |url = http://www.portlandtribune.com/news/story.php?story_id=25157 |work = The Portland Tribune |date = July 9, 2004 |access-date = June 7, 2007 |archive-url = https://web.archive.org/web/20110608041835/http://www.portlandtribune.com/news/story.php?story_id=25157 |archive-date = June 8, 2011 |url-status = dead }}

Throughout 2019, a series of wildfires were ongoing in Oregon on indigenous land belonging to the Umpqua Tribe. The Umpqua Tribe lost possession to their former territory in 1853, which is now known as Elliott State Forest. Elliott State Forest has been the subject of many deforestation initiatives over past years. In December 2018, the Umpqua tribe settled in Oregon after purchasing land from the Bureau of Land Management. Michael Rondeau, a descendent of the Umpqua tribe, expressed his contradictory emotions on the acquisition, stating that he felt "sadness that my grandparents and great aunts and uncles and beyond that did not have a day of recognition". On July 14, 2019, in the Milepost 97 wildfires, 25% of the Umpqua's forest territory burned down.{{Cite web |last=Smith |first=Anna V. |title=A tale of restored tribal lands turns bittersweet in the wake of an Oregon wildfire {{!}} Cascade PBS News |url=https://crosscut.com/environment/2019/08/tale-restored-tribal-lands-turns-bittersweet-wake-oregon-wildfire |access-date=2024-05-02 |website=crosscut.com |language=en}}

On March 7, 2022, Columbia Riverkeeper, a climate advocacy group, sued Weyerhaeuser, a timber and forest products company, for possible contamination of the Columbia River. Columbia Riverkeeper accused Weyerhaeuser of releasing harmful levels of runoff through their Longview Mill into the Columbia River. Furthermore, Columbia Riverkeeper stated that runoff could result in harmful bacteria growth. As of May 6, 2022, Weyerhaeuser reached a settlement with Columbia Riverkeeper. Weyerhaeuser was determined to contribute US$600,000 for river restoration and proposed potential fines of up to US$5,000 for each subsequent act of pollution between 2023 and 2025.{{Cite web |last=Brynelson |first=Troy |date=May 10, 2022 |title=Environmental group, timber firm Weyerhaeuser to settle over pollution claims at Longview timber mill |url=https://www.opb.org/article/2022/05/10/weyerhaeuser-timber-producers-longview-washington-columbia-riverkeeper-environmental-group/ |access-date=2024-05-02 |website=opb |language=en}}

{{Main|Nutrient cycling in the Columbia River Basin}}

Both natural and anthropogenic processes are involved in the cycling of nutrients in the Columbia River basin. Natural processes in the system include estuarine mixing of fresh and ocean waters, and climate variability patterns such as the Pacific Decadal Oscillation and the El Nino Southern Oscillation (both climatic cycles that affect the amount of regional snowpack and river discharge).{{Cite web|url=http://www.ecy.wa.gov/programs/eap/Nitrogen/FateTransport.html|title=Fate and Transport of Nitrogen {{!}} Environmental Assessment Program {{!}} Washington State Department of Ecology, Puget Sound|website=www.ecy.wa.gov|access-date=November 7, 2017|url-status=dead|archive-url=https://web.archive.org/web/20171208003427/http://www.ecy.wa.gov/programs/eap/Nitrogen/FateTransport.html|archive-date=December 8, 2017|df=mdy-all}}{{Cite journal |last1 = Hamlet |first1 = Alan F. |last2 = Lettenmaier |first2 = Dennis P. |date = November 1, 1999 |title = Columbia River Streamflow Forecasting Based on ENSO and PDO Climate Signals |journal = Journal of Water Resources Planning and Management |volume = 125 |issue = 6 |pages = 333–341 |doi = 10.1061/(ASCE)0733-9496(1999)125:6(333) }} Natural sources of nutrients in the Columbia River include weathering, leaf litter, salmon carcasses, runoff from its tributaries, and ocean estuary exchange. Major anthropogenic impacts on nutrients in the basin are due to fertilizers from agriculture, sewage systems, logging, and the construction of dams.{{Cite web|url=http://www.ecy.wa.gov/programs/eap/Nitrogen/NitrogenNaturalSources.html|title=Natural Sources of Nitrogen {{!}} Sources and Pathways {{!}} Environmental Assessment Program {{!}} Washington State Department of Ecology|website=www.ecy.wa.gov|access-date=November 4, 2017|url-status=dead|archive-url=https://web.archive.org/web/20171208003233/http://www.ecy.wa.gov/programs/eap/Nitrogen/NitrogenNaturalSources.html|archive-date=December 8, 2017|df=mdy-all}}{{Cite journal |last = Hileman |first = James |date = July 1975 |title = Columbia River Nutrient Study |journal = Environmental Protection Agency }}

Nutrient dynamics vary in the river basin from the headwaters to the main river and dams, to finally reaching the Columbia River estuary and ocean. Upstream in the headwaters, salmon runs are the main source of nutrients.{{Cite news |url = https://www.wildsalmoncenter.org/work/why-protect-salmon/ |title = Why Protect Salmon – Wild Salmon Center |work = Wild Salmon Center |access-date = November 27, 2017 |language = en-US |archive-url = https://web.archive.org/web/20171207140007/https://www.wildsalmoncenter.org/work/why-protect-salmon/ |archive-date = December 7, 2017 |url-status = live }} Dams along the river impact nutrient cycling by increasing residence time of nutrients, and reducing the transport of silicate to the estuary, which directly impacts diatoms, a type of phytoplankton.{{Cite journal |last1 = Friedl |first1 = Gabriela |last2 = Wüest |first2 = Alfred |date = April 1, 2002 |title = Disrupting biogeochemical cycles – Consequences of damming |journal = Aquatic Sciences |language = en |volume = 64 |issue = 1 |pages = 55–65 |doi = 10.1007/s00027-002-8054-0 |bibcode = 2002AqSci..64...55F |s2cid = 44859140 |issn = 1015-1621 |url = https://www.dora.lib4ri.ch/eawag/islandora/object/eawag%3A4444 |access-date = July 11, 2019 |archive-url = https://web.archive.org/web/20191229142113/https://www.dora.lib4ri.ch/eawag/islandora/object/eawag%3A4444 |archive-date = December 29, 2019 |url-status = live }} The dams are also a barrier to salmon migration and can increase the amount of methane locally produced. The Columbia River estuary exports high rates of nutrients into the Pacific,{{Cite journal |last1 = Gilbert |first1 = Melissa |last2 = Needoba |first2 = Joseph |last3 = Koch |first3 = Corey |last4 = Barnard |first4 = Andrew |last5 = Baptista |first5 = Antonio |date = July 1, 2013 |title = Nutrient Loading and Transformations in the Columbia River Estuary Determined by High-Resolution In Situ Sensors |journal = Estuaries and Coasts |language = en |volume = 36 |issue = 4 |pages = 708–727 |doi = 10.1007/s12237-013-9597-0 |bibcode = 2013EstCo..36..708G |s2cid = 85414307 |issn = 1559-2723 }} except for nitrogen, which is delivered into the estuary by ocean upwelling sources.{{Cite journal |last1 = Lohan |first1 = Maeve C. |last2 = Bruland |first2 = Kenneth W. |date = February 1, 2006 |title = Importance of vertical mixing for additional sources of nitrate and iron to surface waters of the Columbia River plume: Implications for biology |journal = Marine Chemistry |volume = 98 |issue = 2 |pages = 260–273 |doi = 10.1016/j.marchem.2005.10.003 |bibcode = 2006MarCh..98..260L }}

{{Main|Columbia River drainage basin}}

File:08gorge2.jpeg in George, Washington]]

Most of the Columbia's drainage basin (which, at {{convert|258000|mi2|km2|disp=or}}, is about the size of France){{cite web |last1 = Booth |first1 = Bibi |last2 = Fischman |first2 = Shelly |title = The Columbia River Basin |publisher = U.S. Bureau of Land Management |url = http://www.blm.gov/education/00_resources/articles/Columbia_river_basin/article.html |archive-url = https://web.archive.org/web/20080411153836/http://www.blm.gov/education/00_resources/articles/Columbia_river_basin/article.html |archive-date = April 11, 2008 }} lies roughly between the Rocky Mountains on the east and the Cascade Mountains on the west. In the United States and Canada the term watershed is often used to mean drainage basin. The term Columbia Basin is used to refer not only to the entire drainage basin but also to subsets of the river's watershed, such as the relatively flat and unforested area in eastern Washington bounded by the Cascades, the Rocky Mountains, and the Blue Mountains.{{sfn|Meinig|1995|p=4}} Within the watershed are diverse landforms including mountains, arid plateaus, river valleys, rolling uplands, and deep gorges. Grand Teton National Park lies in the watershed, as well as parts of Yellowstone National Park, Glacier National Park, Mount Rainier National Park, and North Cascades National Park. Canadian National Parks in the watershed include Kootenay National Park, Yoho National Park, Glacier National Park, and Mount Revelstoke National Park. Hells Canyon, the deepest gorge in North America, and the Columbia Gorge are in the watershed. Vegetation varies widely, ranging from western hemlock and western redcedar in the moist regions to sagebrush in the arid regions. The watershed provides habitat for 609 known fish and wildlife species, including the bull trout, bald eagle, gray wolf, grizzly bear, and Canada lynx.

The World Wide Fund for Nature (WWF) divides the waters of the Columbia and its tributaries into three freshwater ecoregions: Columbia Glaciated, Columbia Unglaciated, and Upper Snake. The Columbia Glaciated ecoregion, about a third of the total watershed, lies in the north and was covered with ice sheets during the Pleistocene. The ecoregion includes the mainstem Columbia north of the Snake River and tributaries such as the Yakima, Okanagan, Pend Oreille, Clark Fork, and Kootenay rivers. The effects of glaciation include a number of large lakes and a relatively low diversity of freshwater fish. The Upper Snake ecoregion is defined as the Snake River watershed above Shoshone Falls, which totally blocks fish migration. This region has 14 species of fish, many of which are endemic. The Columbia Unglaciated ecoregion makes up the rest of the watershed. It includes the mainstem Columbia below the Snake River and tributaries such as the Salmon, John Day, Deschutes, and lower Snake Rivers. Of the three ecoregions it is the richest in terms of freshwater species diversity. There are 35 species of fish, of which four are endemic. There are also high levels of mollusk endemism.{{sfn|Abell|Olsen|Dinerstein|Hurley|2000|pp=166–69}}{{cite web |url = http://www.feow.org/ecoregion_details.php?eco=120 |title = Columbia Glaciated |publisher = World Wide Fund for Nature and The Nature Conservancy |year = 2008 |access-date = September 25, 2008 |archive-url = https://web.archive.org/web/20131101053119/http://www.feow.org/ecoregion_details.php?eco=120 |archive-date = November 1, 2013 |url-status = dead }}; {{cite web |url = http://www.feow.org/ecoregion_details.php?eco=121 |archive-url = https://web.archive.org/web/20131101052230/http://www.feow.org/ecoregion_details.php?eco=121 |archive-date = November 1, 2013 |url-status = dead |title = Columbia Unglaciated |publisher = World Wide Fund for Nature and The Nature Conservancy |year = 2008 |access-date = September 25, 2008 }}; {{cite web |url = http://www.feow.org/ecoregion_details.php?eco=122 |archive-url = https://web.archive.org/web/20131101062512/http://www.feow.org/ecoregion_details.php?eco=122 |archive-date = November 1, 2013 |url-status = dead |title = Upper Snake |publisher = World Wide Fund for Nature and The Nature Conservancy |year = 2008 |access-date = September 25, 2008 }}

In 2016, over eight million people lived within the Columbia's drainage basin. Of this total about 3.5 million people lived in Oregon, 2.1 million in Washington, 1.7 million in Idaho, half a million in British Columbia, and 0.4 million in Montana. Population in the watershed has been rising for many decades and is projected to rise to about 10 million by 2030. The highest population densities are found west of the Cascade Mountains along the I-5 corridor, especially in the Portland-Vancouver urban area. High densities are also found around Spokane, Washington, and Boise, Idaho. Although much of the watershed is rural and sparsely populated, areas with recreational and scenic values are growing rapidly. The central Oregon county of Deschutes is the fastest-growing in the state. Populations have also been growing just east of the Cascades in central Washington around the city of Yakima and the Tri-Cities area. Projections for the coming decades assume growth throughout the watershed. The Canadian part of the Okanagan subbasin is also growing rapidly.{{cite web |last1 = Bilby |first1 = Robert |last2 = Hanna |first2 = Susan |last3 = Huntly |first3 = Nancy |author-link3=Nancy Huntly|title = Human Population Impacts on Columbia River Basin Fish and Wildlife |publisher = Independent Scientific Advisory Board |date = July 8, 2007 |url = http://www.nwcouncil.org/library/isab/isab2007-3.pdf |access-date = September 15, 2008 |display-authors = etal |archive-url = https://web.archive.org/web/20130117052954/http://www.nwcouncil.org/library/isab/isab2007-3.pdf |archive-date = January 17, 2013 |url-status = dead |df = mdy-all }}

Climate varies greatly within the watershed. Elevation ranges from sea level at the river mouth to more than {{convert|14000|ft|m}} in the mountains, and temperatures vary with elevation. The highest peak is Mount Rainier, at {{convert|14411|ft|m}}. High elevations have cold winters and short cool summers; interior regions are subject to great temperature variability and severe droughts. Over some of the watershed, especially west of the Cascade Mountains, precipitation maximums occur in winter, when Pacific storms come ashore. Atmospheric conditions block the flow of moisture in summer, which is generally dry except for occasional thunderstorms in the interior. In some of the eastern parts of the watershed, especially shrub-steppe regions with Continental climate patterns, precipitation maximums occur in early summer.{{cite web |title = Columbia River Water Management Report, Chapter 2 |publisher = U.S. Army Corps of Engineers, Water Management Division |year = 2005 |url = http://www.nwd-wc.usace.army.mil/crwmg/reports/bluebook/2005/Chapter2%202005.pdf |access-date = September 19, 2008 |archive-url = https://web.archive.org/web/20140812175319/http://www.nwd-wc.usace.army.mil/crwmg/reports/bluebook/2005/Chapter2%202005.pdf |archive-date = August 12, 2014 |url-status = dead }} Annual precipitation varies from more than {{convert|100|in|cm}} a year in the Cascades to less than {{convert|8|in|cm}} in the interior. Much of the watershed gets less than {{convert|12|in|cm}} a year.

Several major North American drainage basins and many minor ones border the Columbia River's drainage basin. To the east, in northern Wyoming and Montana, the Continental Divide separates the Columbia watershed from the Mississippi-Missouri watershed, which empties into the Gulf of Mexico. To the northeast, mostly along the southern border between British Columbia and Alberta, the Continental Divide separates the Columbia watershed from the Nelson-Lake Winnipeg-Saskatchewan watershed, which empties into Hudson Bay. The Mississippi and Nelson watersheds are separated by the Laurentian Divide, which meets the Continental Divide at Triple Divide Peak near the headwaters of the Columbia's Flathead River tributary. This point marks the meeting of three of North America's main drainage patterns, to the Pacific Ocean, to Hudson Bay, and to the Atlantic Ocean via the Gulf of Mexico.{{cite web |title = Watersheds (map) |publisher = Commission for Environmental Cooperation |year = 2006 |url = http://www.cec.org/naatlas/img/NA-Watersheds.gif |archive-url = http://webarchive.loc.gov/all/20080807145118/http://www.cec.org/naatlas/img/NA-Watersheds.gif |archive-date = August 7, 2008 |url-status = dead }}{{cite web |title = Continental Divides in North Dakota and North America |work = North Dakota Geological Survey Newsletter |last = Gonzalez |first = Mark A. |year = 2003 |url = https://www.dmr.nd.gov/ndgs/NEWSLETTER/NLS03/pdf/Divide.pdf |access-date = September 12, 2008 |archive-url = https://web.archive.org/web/20130117052801/https://www.dmr.nd.gov/ndgs/NEWSLETTER/NLS03/pdf/Divide.pdf |archive-date = January 17, 2013 |url-status = dead }}

Further north along the Continental Divide, a short portion of the combined Continental and Laurentian divides separate the Columbia watershed from the Mackenzie-Slave-Athabasca watershed, which empties into the Arctic Ocean. The Nelson and Mackenzie watersheds are separated by a divide between streams flowing to the Arctic Ocean and those of the Hudson Bay watershed.{{cite web |title = Atlas of Canada: Drainage Basins |url = http://geogratis.gc.ca/api/en/nrcan-rncan/ess-sst/dc475fb0-8893-11e0-9ab7-6cf049291510.html |publisher = Natural Resources Canada |year = 2010 |access-date = September 29, 2015 |archive-url = https://web.archive.org/web/20160314090740/http://geogratis.gc.ca/api/en/nrcan-rncan/ess-sst/dc475fb0-8893-11e0-9ab7-6cf049291510.html |archive-date = March 14, 2016 |url-status = live }} This divide meets the Continental Divide at Snow Dome (also known as Dome), near the northernmost bend of the Columbia River.{{sfn|Palmer|Thorington|1921|p=119}}

To the southeast, in western Wyoming, another divide separates the Columbia watershed from the Colorado–Green watershed, which empties into the Gulf of California. The Columbia, Colorado, and Mississippi watersheds meet at Three Waters Mountain in the Wind River Range of {{nowrap|Wyoming}}.{{cite journal |last = Gonzalez |first = Mark A. |title = Continental Divides in North Dakota and North America |journal = NGDS Newsletter |volume = 30 |number = 1 |pages = 5–6 |publisher = North Dakota Geological Survey |year = 2002 |url = https://www.dmr.nd.gov/ndgs/Newsletter/NLS03/pdf/Divide.pdf |access-date = December 2, 2016 |url-status = dead |archive-url = https://web.archive.org/web/20130117052801/https://www.dmr.nd.gov/ndgs/NEWSLETTER/NLS03/pdf/Divide.pdf |archive-date = January 17, 2013 }} To the south, in Oregon, Nevada, Utah, Idaho, and Wyoming, the Columbia watershed is divided from the Great Basin, whose several watersheds are endorheic, not emptying into any ocean but rather drying up or sinking into sumps. Great Basin watersheds that share a border with the Columbia watershed include Harney Basin, Humboldt River, and Great Salt Lake. The associated triple divide points are Commissary Ridge North, Wyoming,{{cite peakbagger |pid = 5429 |name = Commissary Ridge North, Wyoming }} and Sproats Meadow Northwest, Oregon.{{cite peakbagger |pid = 3248 |name = Sproats Meadow Northwest, Oregon }} To the north, mostly in British Columbia, the Columbia watershed borders the Fraser River watershed. To the west and southwest the Columbia watershed borders a number of smaller watersheds that drain to the Pacific Ocean, such as the Klamath River in Oregon and California and the Puget Sound Basin in Washington.

{{See also|List of tributaries of the Columbia River}}

File:Deschutes River.jpg

The Columbia receives more than 60 significant tributaries. The four largest that empty directly into the Columbia (measured either by discharge or by size of watershed) are the Snake River (mostly in Idaho), the Willamette River (in northwest Oregon), the Kootenay River (mostly in British Columbia), and the Pend Oreille River (mostly in northern Washington and Idaho, also known as the lower part of the Clark Fork). Each of these four averages more than {{convert|20000|cuft/s|m3/s}} and drains an area of more than {{convert|20000|mi2|km2}}.

The Snake is by far the largest tributary. Its watershed of {{convert|108000|mi2|km2}} is larger than the state of Idaho. Its discharge is roughly a third of the Columbia's at the rivers' confluence but compared to the Columbia upstream of the confluence the Snake is longer (113%) and has a larger drainage basin (104%).

The Pend Oreille River system (including its main tributaries, the Clark Fork and Flathead rivers) is also similar in size to the Columbia at their confluence. Compared to the Columbia River above the two rivers' confluence, the Pend Oreille-Clark-Flathead is nearly as long (about 86%), its basin about three-fourths as large (76%), and its discharge over a third (37%).Calculated mainly with data from: {{cite web |url = https://wdr.water.usgs.gov/wy2007/search.jsp |title = Water-resources data for the United States, Water Year 2007 |publisher = United States Geological Survey |access-date = September 16, 2008 |archive-url = https://web.archive.org/web/20081206000126/http://wdr.water.usgs.gov/wy2007/search.jsp |archive-date = December 6, 2008 |url-status = dead }}

File:Kp'itl'els (Brilliant, BC), Sinixt village site and historic home of the Alex Christian family.jpg), Sinixt village site at the confluence of the Kootenay and Columbia Rivers|alt=View of an overgrown field with a rotting fencepost in the foreground and a range of hills in the distance]]

{| class="wikitable collapsible sortable state = uncollapsed"

|-

!Tributary

!colspan=2|Average discharge

!colspan=2|Drainage basin

|-

!

!ft³/s

!m³/s

!mi²

!km²

|-

|Snake River

|{{convert|56900|cuft|m3|sigfig=3|disp=table}}

|{{convert|107500|mi2|km2|sigfig=4|disp=table}}{{cite web |title = USGS Water Resources of the United States: Boundary Descriptions and Names of Regions, Subregions, Accounting Units and Cataloging Units |publisher = United States Geological Survey |year = 2007 |url = http://water.usgs.gov/GIS/huc_name.html |access-date = September 16, 2008 |archive-url = https://web.archive.org/web/20170625160942/https://water.usgs.gov/GIS/huc_name.html |archive-date = June 25, 2017 |url-status = live }}'' Sum of Subregion 1704, Upper Snake, Subregion 1705, Middle Snake, and Subregion 1706, Lower Snake.

|-

|Willamette River

|{{convert|37400|cuft|m3|sigfig=3|disp=table}}

|{{convert|11500|mi2|km2|sigfig=4|disp=table}}{{cite web |title = Willamette Watershed |url = https://www.portlandonline.com/bes/index.cfm?c=32749 |publisher = Portland Bureau of Environmental Services |year = 2008 |access-date = September 16, 2008 |archive-url = https://web.archive.org/web/20170415010826/https://www.portlandoregon.gov/bes/30938 |archive-date = April 15, 2017 |url-status = live }}

|-

|Kootenay River (Kootenai)

|{{convert|30650|cuft|m3|sigfig=3|disp=table}}[http://www.nwcouncil.org/fw/subbasinplanning/kootenai/plan/Assessment_01IntroOverview.pdf Subbasin Overview] {{Webarchive|url=https://web.archive.org/web/20090325213657/http://www.nwcouncil.org/fw/subbasinplanning/kootenai/plan/Assessment_01IntroOverview.pdf |date=March 25, 2009 }} , [http://www.nwcouncil.org/fw/subbasinplanning/kootenai/plan/ Kootenai Subbasin Plan] {{Webarchive|url=https://web.archive.org/web/20080921122638/http://www.nwcouncil.org/fw/subbasinplanning/kootenai/plan/ |date=September 21, 2008 }}, Northwest Power and Conservation Council

|{{convert|19420|mi2|km2|sigfig=4|disp=table}}{{cite web |url = http://virtualmuseum.ca/Exhibitions/Hydro/en/stories/rivers.php |title = Balance of Power: Hydroelectric Development in Southeastern British Columbia |publisher = Touchstones Nelson: Museum of Art and History |year = 2007 |access-date = September 16, 2008 |archive-url = https://web.archive.org/web/20111106161101/http://virtualmuseum.ca/Exhibitions/Hydro/en/stories/rivers.php |archive-date = November 6, 2011 |url-status = dead }}

|-

|Pend Oreille River

|{{convert|26430|cuft|m3|sigfig=3|disp=table}}{{cite web |title = Pend Oreille, Kettle, and Colville River Basins, and the Columbia River from the International Boundary to the confluence with the Spokane River |publisher = United States Geological Survey |year = 2005 |url = http://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/pdf/wa00103ADR2005_Figure48.pdf |access-date = October 19, 2008 |archive-url = https://web.archive.org/web/20081018080145/http://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/pdf/wa00103ADR2005_Figure48.pdf |archive-date = October 18, 2008 |url-status = live }} Discharge data taken from a gauge at the US–Canada border, {{convert|16.1|mi|km}} from the mouth, measuring data from about {{convert|25200|mi2|km2}}, about 98 percent of the total watershed.

|{{convert|25800|mi2|km2|sigfig=3|disp=table}}{{cite web |url = http://www.llbc.leg.bc.ca/public/pubdocs/bcdocs/409063/seven_mile_project.pdf |title = Seven Mile Project Water Use Plan |publisher = BC Hydro |date = December 8, 2006 |access-date = September 3, 2009 |archive-url = https://web.archive.org/web/20170822011818/http://www.llbc.leg.bc.ca/public/pubdocs/bcdocs/409063/seven_mile_project.pdf |archive-date = August 22, 2017 |url-status = dead }}

|-

|Cowlitz River

|{{convert|9140|cuft|m3|sigfig=3|disp=table}}{{cite web |title = Water-data report 2007: USGS 14243000 Cowlitz River at Castle Rock, WA |url = http://wdr.water.usgs.gov/wy2007/pdfs/14243000.2007.pdf |publisher = United States Geological Survey |year = 2007 |access-date = October 24, 2008 |archive-url = https://web.archive.org/web/20081029095450/http://wdr.water.usgs.gov/wy2007/pdfs/14243000.2007.pdf |archive-date = October 29, 2008 |url-status = dead }} Discharge data taken from gauge 14243000 at Castle Rock, {{convert|17.3|mi|km}} from the mouth, measuring the flow from about {{convert|2238|sqmi|km2}} or 85 percent of the total watershed.

|{{convert|2586|mi2|km2|sigfig=3|disp=table}}

Calculated by summing subbasin sizes listed in [http://www.nwcouncil.org/fw/subbasinplanning/lowerColumbia/plan/Vol%20II%20H--L%20Columbia%20Tribs.pdf Lower Columbia Tributaries] {{Webarchive|url=https://web.archive.org/web/20081002170752/http://www.nwcouncil.org/fw/subbasinplanning/lowerColumbia/plan/Vol%20II%20H--L%20Columbia%20Tribs.pdf |date=October 2, 2008 }} , Northwest Power and Conservation Council; and [http://www.nwcouncil.org/fw/subbasinplanning/lowerColumbia/plan/2004_05/ManagementPlan/VolumeII/MP%20Vol%20II%20Ch%2008%20Toutle2.pdf Toutle Management Plan] {{Webarchive|url=https://web.archive.org/web/20081002170813/http://www.nwcouncil.org/fw/subbasinplanning/lowerColumbia/plan/2004_05/ManagementPlan/VolumeII/MP%20Vol%20II%20Ch%2008%20Toutle2.pdf |date=October 2, 2008 }}, Northwest Power and Conservation Council. Retrieved on September 16, 2008.

|-

|Spokane River

|{{convert|7900|cuft|m3|sigfig=3|disp=table}}{{sfn|Benke|Cushing|2005|p=650}}

|{{convert|6680|mi2|km2|sigfig=3|disp=table}}

|-

|Lewis River

|{{convert|6125|cuft|m3|sigfig=3|disp=table}}{{cite web |last = Lower Columbia Fish Recovery Board |title = volume II – Subbasin Plan Chapter G – NF and EF Lewis |work = Lower Columbia Salmon Recovery and Fish & Wildlife Subbasin Plan |publisher = Northwest Power and Conservation Council |date = December 2004 |url = http://www.nwcouncil.org/fw/subbasinplanning/lowerColumbia/plan/Vol%20II%20G--Lewis.pdf |access-date = October 14, 2008 |archive-url = https://web.archive.org/web/20060823103132/http://www.nwcouncil.org/fw/subbasinplanning/lowerColumbia/plan/Vol%20II%20G--Lewis.pdf |archive-date = August 23, 2006 |url-status = dead |df = mdy-all }}

|{{convert|1046|mi2|km2|sigfig=3|disp=table}}{{cite web |title = Description: Lewis River Drainage, Mount St. Helens, Washington |publisher = United States Geological Survey |year = 1999 |url = http://vulcan.wr.usgs.gov/Volcanoes/MSH/Hydrology/Drainages/Lewis/description_lewis.html |access-date = October 14, 2008 |archive-url = https://web.archive.org/web/20081006201419/http://vulcan.wr.usgs.gov/Volcanoes/MSH/Hydrology/Drainages/Lewis/description_lewis.html |archive-date = October 6, 2008 |url-status = live }}

|-

|Deschutes River

|{{convert|5845|cuft|m3|sigfig=3|disp=table}}{{sfn|Loy|Allan|Buckley|Meacham|2001|pp=164–65}}

|{{convert|10700|mi2|km2|sigfig=3|disp=table}}

|-

|Yakima River

|{{convert|3542|cuft|m3|sigfig=3|disp=table}}{{cite web |publisher = United States Geological Survey |url = http://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/pdf/wa00103ADR2005_Figure60.pdf |title = Yakima River and Esquatzel Coulee Basins and the Columbia River from Richland to Kennewick, Water Resources Data-Washington Water Year 2005 |access-date = October 16, 2008 |archive-url = https://web.archive.org/web/20081018074714/http://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/pdf/wa00103ADR2005_Figure60.pdf |archive-date = October 18, 2008 |url-status = live }} Discharge data from gauge 12510500 at Kiona, {{convert|29.9|mi|km}} from the mouth, measuring the flow from about 91 percent of the total watershed.

|{{convert|6150|mi2|km2|sigfig=3|disp=table}}{{cite web |url = http://www.nwcouncil.org/fw/subbasinplanning/yakima/plan/1_Overview.pdf |title = Yakima Subbasin Plan Overview |publisher = Northwest Power and Conservation Council |access-date = September 16, 2008 |archive-url = https://web.archive.org/web/20081002170908/http://www.nwcouncil.org/fw/subbasinplanning/yakima/plan/1_Overview.pdf |archive-date = October 2, 2008 |url-status = dead }}

|-

|Wenatchee River

|{{convert|3079|cuft|m3|sigfig=2|disp=table}}{{cite web |publisher = United States Geological Survey |url = http://pubs.usgs.gov/wdr/WDR-WA-02-1/data/12459000.2002.sw.pdf |title = Wenatchee River Basin: 12459000 Wenatchee River at Peshastin, WA |access-date = October 16, 2008 |archive-url = https://web.archive.org/web/20121008191739/http://pubs.usgs.gov/wdr/WDR-WA-02-1/data/12459000.2002.sw.pdf |archive-date = October 8, 2012 |url-status = live }}. Discharge data from gauge 12459000 at Peshastin, {{convert|21.5|mi|km}} from the mouth, measuring the flow from about {{convert|1000|mi2|km2}} or 77 percent of the total watershed.

|{{convert|1350|mi2|km2|sigfig=3|disp=table}}{{cite web |url = http://water.usgs.gov/GIS/huc_name.html |title = Boundary Descriptions and Names of Regions |publisher = United States Geological Survey |access-date = September 10, 2008 |archive-url = https://web.archive.org/web/20120427215107/http://water.usgs.gov/GIS/huc_name.html |archive-date = April 27, 2012 |url-status = live }}

|-

|Okanogan River

|{{convert|3039|cuft|m3|sigfig=2|disp=table}}[http://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/ Water Data Report WA-05-1] {{Webarchive|url=https://web.archive.org/web/20070429052414/http://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/ |date=April 29, 2007 }}, chapter [http://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/pdf/wa00103ADR2005_Figure52.pdf Okanagan River Basin] {{Webarchive|url=https://web.archive.org/web/20081018075111/http://pubs.usgs.gov/wdr/2005/wdr-wa-05-1/pdf/wa00103ADR2005_Figure52.pdf |date=October 18, 2008 }}. Retrieved on April 20, 2007. Discharge data taken at Malott, Washington, {{convert|17|mi|km}} from the mouth, measuring the flow from about {{convert|8080|sqmi|km2}}, about 97 percent of the total watershed.

|{{convert|8200|mi2|km2|sigfig=3|disp=table}}{{cite web |author = School of Natural Resources |url = http://www.snre.umich.edu/ecomgt//pubs/transboundary/Okanagan.pdf |page = 2 |year = 2001 |title = Okanagan River Basin |publisher = University of Michigan |access-date = September 29, 2015 |archive-url = https://web.archive.org/web/20170701065515/http://www.snre.umich.edu/ecomgt/pubs/transboundary/Okanagan.pdf |archive-date = July 1, 2017 |url-status = live }}

|-

|Kettle River

|{{convert|2925|cuft|m3|sigfig=2|disp=table}}{{cite web |title = Water-Data Report 2007: 12404500 Kettle River near Laurier, WA |publisher = United States Geological Survey |year = 2007 |url = http://wdr.water.usgs.gov/wy2007/pdfs/12404500.2007.pdf |access-date = October 18, 2008 |archive-url = https://web.archive.org/web/20120220145826/http://wdr.water.usgs.gov/wy2007/pdfs/12404500.2007.pdf |archive-date = February 20, 2012 |url-status = dead }} Discharge data from a gauge near Laurier, {{convert|29.71|mi|km}} from the mouth, measuring the flow from about {{convert|3800|mi2|km2}}, about 90 percent of the total watershed.

|{{convert|4200|mi2|km2|sigfig=4|disp=table}}{{cite web |url = http://www.nwcouncil.org/fw/subbasinplanning/admin/level2/intermtn/plan/29_uprcol_overview.pdf |title = Upper Columbia Subbasin Overview |pages = 29–8 |publisher = Northwest Power and Conservation Council |access-date = September 16, 2008 |archive-url = https://web.archive.org/web/20081002170918/http://www.nwcouncil.org/fw/subbasinplanning/admin/level2/intermtn/plan/29_uprcol_overview.pdf |archive-date = October 2, 2008 |url-status = dead |df = mdy-all }}

|-

|Sandy River

|{{convert|2257|cuft|m3|sigfig=2|disp=table}}{{cite web |title = Water-Data Report 2007: 14142500 Sandy River Below Bull Run River, near Bull Run, OR |publisher = United States Geological Survey |year = 2008 |url = http://wdr.water.usgs.gov/wy2007/pdfs/14142500.2007.pdf |access-date = October 19, 2008 |archive-url = https://web.archive.org/web/20120220145835/http://wdr.water.usgs.gov/wy2007/pdfs/14142500.2007.pdf |archive-date = February 20, 2012 |url-status = dead }} Discharge data from a gauge near Bull Run, {{convert|18.4|mi|km}} from the mouth, measuring the flow from about {{convert|436|mi2|km2}}, about 86 percent of the total watershed.

|{{convert|508|mi2|km2|sigfig=4|disp=table}}{{cite web |last = Taylor |first = Barbara |title = Salmon and Steelhead Runs and Related Events of the Sandy River Basin – A Historical Perspective |publisher = Portland General Electric |date = December 1998 |url = http://www.portlandgeneral.com/community_environment/initiatives/protecting_fish/sandy_river/docs/sandy_river_history_full.pdf |access-date = December 18, 2010 |url-status = dead |archive-url = https://web.archive.org/web/20150427184240/https://www.portlandgeneral.com/community_environment/initiatives/protecting_fish/sandy_river/docs/sandy_river_history_full.pdf |archive-date = April 27, 2015 |df = mdy }}

|-

|John Day River

|{{convert|2060|cuft|m3|sigfig=2|disp=table}}{{cite web |title = Water-Data Report 2007: 14048000 John Day River at McDonald Ferry, OR |publisher = United States Geological Survey |year = 2007 |url = http://wdr.water.usgs.gov/wy2007/pdfs/14048000.2007.pdf |access-date = October 19, 2008 |archive-url = https://web.archive.org/web/20120220145844/http://wdr.water.usgs.gov/wy2007/pdfs/14048000.2007.pdf |archive-date = February 20, 2012 |url-status = dead }} Discharge data from a gauge at McDonald Ferry, {{convert|20.9|mi|km}} from the mouth, measuring the flow from about {{convert|7580|mi2|km2}}, about 95 percent of the total watershed.

|{{convert|8010|mi2|km2|sigfig=4|disp=table}}{{cite web |last1 = Powell |first1 = Russ |last2 = Delano |first2 = Kenneth |title = John Day River Subbasin Fish Habitat Enhancement Project |publisher = Bonneville Power Administration |year = 2004 |url = http://pisces.bpa.gov/release/documents/documentviewer.aspx?pub=H00005632-3.pdf |access-date = October 18, 2008 |archive-url = https://web.archive.org/web/20081029095450/http://pisces.bpa.gov/release/documents/documentviewer.aspx?pub=H00005632-3.pdf |archive-date = October 29, 2008 |url-status = dead }}

|}

{{clear}}

{{Portal|Pacific Northwest|Rivers}}

{{div col}}

• Columbia Park (Kennewick, Washington), a {{convert|400|acre|ha|adj=on}} recreational area
• Columbia River Estuary
• Columbia River Maritime Museum, Astoria, Oregon
• Empire Builder, an Amtrak rail line that follows the river from Portland to Pasco, Washington
• Estella Mine, an abandoned mine with a view of the Columbia River Valley
• Historic Columbia River Highway, a scenic highway on the Oregon side
• List of crossings of the Columbia River
• List of dams in the Columbia River watershed
• List of longest rivers of Canada
• List of longest rivers of the United States (by main stem)
• List of longest streams of Oregon
• Lists of ecoregions in North America and Oregon
• Lists of rivers of British Columbia, Oregon, and Washington
• Okanagan Trail, a historic trail that followed the Columbia and Okanagan rivers
• Robert Gray's Columbia River expedition

{{div col end}}

{{reflist|group=note}}

{{reflist}}

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• {{cite book |last = Affleck |first = Edward L. |title = A Century of Paddlewheelers in the Pacific Northwest, the Yukon, and Alaska |publisher = Alexander Nicholls Press |location = Vancouver, British Columbia |year = 2000 |isbn = 978-0-920034-08-8 }}
• {{cite book |last = Barber |first = Katrine |title = Death of Celilo Falls |publisher = University of Washington Press |location = Seattle |year = 2005 |isbn = 978-0-295-98546-6 |url = https://archive.org/details/deathofcelilofal0000barb }}
• {{cite book |last = Benson |first = Frank W. |title = A Pamphlet Containing All Measures ... |publisher = State of Oregon |date = June 1908 |author-link = Frank W. Benson (Oregon governor) |url = https://books.google.com/books?id=-HsNAAAAYAAJ |via = Google Books }}
• {{cite book |last = Bishop |first = Ellen Morris |title = In Search of Ancient Oregon: A Geological and Natural History |publisher = Timber Press |year = 2003 |location = Portland, Oregon |isbn = 978-0-88192-789-4 }}
• {{cite book |last1 = Benke |first1 = Arthur C. |last2 = Cushing |first2 = Colbert E. |title = Rivers of North America |year = 2005 |publisher = Elsevier |location = New York |isbn = 978-0-12-088253-3 |url-access = registration |url = https://archive.org/details/riversofnorthame0000unse }}
• {{cite book |last = Boyd |first = Robert |title = People of the Dalles: The Indians of Wascopam Mission |url = https://archive.org/details/peopleofdallesin0000boyd |url-access = registration |publisher = University of Nebraska Press |location = Lincoln |year = 1996 |isbn = 978-0-8032-1236-7 }}
• {{cite book |last = Clark |first = Ella E. |title = Indian Legends of the Pacific Northwest |publisher = University of California Press |location = Berkeley, California |year = 2003 |isbn = 978-0-520-23926-5 }}
• {{cite book |last = Corning |first = Howard McKinley |title = Willamette Landings |edition = 2nd |publisher = Oregon Historical Society |location = Portland, Oregon |year = 1977 |isbn = 978-0-87595-042-6 }}
• {{cite book |last = Denton |first = V. L. |title = The Far West Coast |url = https://archive.org/details/farwestcoast0000dent |url-access = registration |publisher = Dent |location = Toronto |year = 1924 |oclc = 918309366 }}
• {{cite book |last = Dietrich |first = William |title = Northwest Passage: The Great Columbia River |publisher = University of Washington Press |place = Seattle |year = 1995 |isbn = 978-0-295-97546-7 }}
• {{cite book |last = Dohnal |first = Cheri |title = Columbia River Gorge: National Treasure on the Old Oregon Trail |publisher = Arcadia Publishing |year = 2003 |isbn = 978-0-7385-2432-0 }}
• {{cite book |last = Dove (Quintasket) |first = Mourning (Christine) |title = Coyote Stories |year = 1990 |orig-year = 1933 |publisher = University of Nebraska Press |location = Lincoln |isbn = 978-0-8032-8169-1 |url-access = registration |url = https://archive.org/details/isbn_9780803281691 }}
• {{cite book |last = Egan |first = Timothy |author-link = Timothy Egan |title = The Good Rain |publisher = Knopf |location = New York |isbn = 978-0-394-57724-1 |year = 1990 |url = https://archive.org/details/goodrainthe00timo }}
• {{cite book |last = Friedman |first = Ralph |title = In Search of Western Oregon |publisher = Caxton Press |location = Caldwell, Idaho |year = 2003 |isbn = 978-0-87004-332-1 |url = https://archive.org/details/insearchofwester00frie }}
• {{cite book |last = Gibbs |first = James A. |author-link = James A. Gibbs |title = Pacific Graveyard |edition = 3rd |publisher = Binford & Mort |location = Portland, Oregon |year = 1964 }}
• {{cite book |last = Harden |first = Blaine |title = A River Lost: The Life and Death of the Columbia |year = 1996 |publisher = W. W. Norton |location = New York |isbn = 978-0-393-03936-8 }}
• {{cite book |last = Harris |first = Stephen L. |year = 1988 |title = Fire Mountains of the West: The Cascade and Mono Lake Volcanoes |location = Missoula, Montana |publisher = Mountain Press Publishing |isbn = 978-0-87842-220-3 |url = https://archive.org/details/firemountainsofw00harr }}
• {{cite book |last = Hayes |first = Derek |title = Historical Atlas of the Pacific Northwest: Maps of Exploration and Discovery |place = Seattle |publisher = Sasquatch Books |year = 1999 |isbn = 978-1-57061-215-2 }}
• {{cite book |last = Hayes |first = Derek |title = Historical Atlas of the Pacific Northwest: Maps of Exploration and Discovery |place = Seattle |publisher = Sasquatch Books |year = 1999a |isbn = 978-1-57061-215-2 }}
• {{cite book |last = Holbrook |first = Stewart |title = The Columbia |publisher = Comstock Editions |year = 1956 |location = San Francisco |isbn = 978-0-89174-051-3 }}
• {{cite book |last1 = Houck |first1 = Michael C. |last2 = Cody |first2 = M. J. |title = Wild in the City |publisher = Oregon Historical Society |location = Portland, Oregon |year = 2000 |isbn = 978-0-87595-273-4 }}
• {{cite book |last = Hunn |first = Eugene S. |title = Nch'i-Wàna: The Big River |publisher = University of Washington Press |location = Seattle |year = 1990 |isbn = 978-0-295-96851-3 |url-access = registration |url = https://archive.org/details/nchiwanathebigri0000hunn }}
• {{cite book |last = Jacobs |first = Melvin C. |title = Winning Oregon: A Study of an Expansionist Movement |publisher = The Caxton Printers |location = Caldwell, Idaho |year = 1938 |oclc = 9474314 }}
• {{cite book |last1 = Loy |first1 = William G. |last2 = Allan |first2 = Stuart |last3 = Buckley |first3 = Aileen R. |last4 = Meacham |first4 = James E. |title = Atlas of Oregon |publisher = University of Oregon Press |location = Eugene, Oregon |date = 2001 |orig-year = 1976 |isbn = 978-0-87114-102-6 }}
• {{cite book|first=William Denison |last=Lyman |year=1909|title=The Columbia River: Its History, Its Myths, Its Scenery, Its Commerce|url=https://archive.org/details/in.ernet.dli.2015.168767 |publisher=G. P. Putnam's Sons}} (see here for full online transcription)
• {{cite book |last = MacGibbon |first = Elma |title = Leaves of Knowledge |publisher = Shaw & Borden |year = 1904 |series = Washington State Library's Classics in Washington History collection |chapter = Columbia River and Pullman |isbn = 978-1-110-68495-3 }}
• {{cite book |last = Mackie |first = Richard Somerset |title = Trading Beyond the Mountains: The British Fur Trade on the Pacific 1793–1843 |year = 1997 |publisher = University of British Columbia Press |location = Vancouver |isbn = 978-0-7748-0613-8 }}
• {{cite book |last = Meinig |first = D. W. |author-link = D.W. Meinig |title = The Great Columbia Plain |orig-year = 1968 |edition = Weyerhaeuser Environmental Classic |year = 1995 |publisher = University of Washington Press |isbn = 978-0-295-97485-9 }}
• {{cite book |last = Mueller |first = Ted |title = Fire, Faults, and Floods: A Road and Trail Guide Exploring the Origins of the Columbia River Basin |publisher = University of Idaho Press |location = Moscow, Idaho |year = 1997 |isbn = 978-0-89301-206-9 |url = https://archive.org/details/firefaultsfloods00muel }}
• {{cite book |last = National Research Council (U.S.) |title = Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival |year = 2004 |publisher = National Academies Press |isbn = 978-0-309-09155-8 }}
• {{cite book |title = The Columbia River Salmon and Steelhead Trout |last = Netboy |first = Anthony |publisher = University of Washington Press |year = 1980 |location = Seattle |isbn = 978-0-295-95768-5 }}
• {{cite book |last1 = Palmer |first1 = Howard |last2 = Thorington |first2 = James Monroe |title = A Climber's Guide to the Rocky Mountains of Canada |publisher = Knickerbocker Press |year = 1921 |location = New York }}
• {{cite book |first = Paul |last = Pitzer |title = Grand Coulee: Harnessing a Dream |location = Pullman, Washington |publisher = Washington State University Press |year = 1994 |isbn = 978-0-87422-110-7 }}
• {{cite book |first=Nellie Bowden |last=Pipes | title=Oregon Historical Quarterly |chapter=Articles in the Oregon Historical Quarterly Relating to the Columbia River, Settlement of Astoria, Lewis and Clark Expedition | volume=27 |number=2 |year=1926 |publisher=Oregon Historical Society|title-link=Oregon Historical Quarterly }}
• {{cite book |last = Pryce |first = Paula |title = Keeping the Lakes' Way: Reburial and Re-creation of a Moral World among an Invisible People |publisher = University of Toronto Press |location = Toronto |year = 1999 |isbn = 978-0-8020-8223-7 }}
• {{cite book |last = Roberts |first = John E. |title = A Discovery Journal: George Vancouver's First Survey Season – 1792 |year = 2005 |publisher = Trafford Publishing |isbn = 978-1-4120-7097-3 }}
• {{cite book |last = Ronda |first = James P. |title = Lewis & Clark Among the Indians |url = https://archive.org/details/lewisclarkamongt00jame |url-access = registration |publisher = University of Nebraska Press |place = Lincoln |year = 1984 |isbn = 978-0-8032-8990-1 }}
• {{cite book |last1 = Rybář |first1 = Jan |last2 = Stemberk |first2 = Josef |last3 = Wagner |first3 = Peter |title = Landslides: Proceedings of the First European Conference on Landslides, Prague, Czech Republic, June 24–26, 2002 |year = 2002 |publisher = Taylor & Francis |isbn = 978-90-5809-393-6 }}
• {{cite book |last = Satterfield |first = Archie |title = Country Roads of Washington |publisher = iUniverse |location = Lincoln |year = 2003 |orig-year = 1989 |isbn = 978-0-595-26863-4 }}
• {{cite book |last1 = Scott |first1 = Harvey W. |author-link = Harvey W. Scott |last2 = Scott |first2 = Leslie M. |year = 1924 |title = History of the Oregon Country |location = Cambridge |publisher = Riverside Press |volume = 3 |isbn = 978-0-665-16710-2 }}
• {{cite book |last1 = Stelling |first1 = Peter L. |last2 = Tucker |first2 = David S. |title = Floods, Faults, and Fire |publisher = Geological Society of America |year = 2007 |location = Bellingham, Washington |isbn = 978-0-8137-0009-0 }}
• {{cite book |last = Timmen |first = Fritz |title = Blow for the Landing |publisher = Caxton Printers |location = Caldwell, Idaho |year = 1972 |isbn = 978-0-87004-221-8 }}
• {{cite book |title = Empty Nets: Indians, Dams, and the Columbia River |last = Ulrich |first = Roberta |publisher = Oregon State University Press |location = Corvallis, Oregon |year = 2007 |isbn = 978-0-87071-469-6 |url = https://archive.org/details/emptynetsindians00ulri }}
• {{cite book |title = Blood Struggle: The Rise of Modern Indian Nations |first = Charles F. |last = Wilkinson |publisher = W. W. Norton |location = New York |year = 2005 |isbn = 978-0-393-05149-0 |url = https://archive.org/details/bloodstruggleris00wilk }}

• White, Richard. The Organic Machine: The Remaking of the Columbia River (Hill and Wang, 1996)

{{Commons category}}

• [https://www.bchydro.com/index.html BC Hydro]
• [http://www.ppl.nl/index.php?option=com_wrapper&view=wrapper&Itemid=82 Bibliography on Water Resources and International Law] Peace Palace Library
• {{cite EB1911|wstitle=Columbia River |volume=6 |short=x}}
• {{Cite NIE|wstitle=Columbia River |short=x}}
• [http://www2.epa.gov/columbiariver Columbia River] {{Webarchive|url=https://web.archive.org/web/20160929021732/http://www2.epa.gov/columbiariver |date=September 29, 2016 }} US Environmental Protection Agency
• [http://www.fs.usda.gov/crgnsa Columbia River Gorge National Scenic Area] from the US Forest Service
• [http://www.critfc.org/ Columbia River Inter-Tribal Fish Commission]
• {{Internet Archive short film|id=gov.fdr.353.3.4|name="The Columbia (1949)"}}
• {{Cite web |url=http://www.iinet.com/~englishriver/LewisClarkColumbiaRiver/Regions/Places/columbia_river.html |title=Timeline of exploration of the Columbia |access-date=September 26, 2007 |archive-url=https://web.archive.org/web/20080102084202/http://www.iinet.com/~englishriver/LewisClarkColumbiaRiver/Regions/Places/columbia_river.html |archive-date=January 2, 2008 |url-status=dead |df=mdy-all }}, dating to the 17th century
• [http://digitalcollections.lib.washington.edu/cdm/search/collection/tollcan/searchterm/columbia/field/all/mode/all/conn/and/order/title/ad/asc University of Washington Libraries Digital Collections – Tollman and Canaris Photographs] Photographs document the salmon fishing industry on the southern Washington coast and in the lower Columbia River around the year 1897 and offer insights about commercial salmon fishing and the techniques used at the beginning of the 20th century.
• [https://web.archive.org/web/20161228163006/http://www.nationalgeographic.com/features/00/earthpulse/columbia/index_flash.html Virtual World: Columbia River] National Geographic via Internet Archive

{{Columbia River}}

{{Washington}}

{{British Columbia hydrography}}

{{Rivers and streams of Portland, Oregon}}

{{Authority control}}

{{Featured article}}

Category:Borders of Oregon

Category:Borders of Washington (state)

Category:Drainage basins of the Pacific Ocean

Category:International rivers of North America

Category:Rivers of Benton County, Washington

Category:Rivers of British Columbia

Category:Rivers of Chelan County, Washington

Category:Rivers of Clark County, Washington

Category:Rivers of Clatsop County, Oregon

Category:Rivers of Cowlitz County, Washington

Category:Rivers of Franklin County, Washington

Category:Rivers of Hood River County, Oregon

Category:Rivers of Multnomah County, Oregon

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Category:Rivers of Wasco County, Oregon

Category:Rivers of Washington (state)

Category:Rivers of Douglas County, Washington

Category:Rivers with fish ladders