The Mighty Columbia
Jon Burch Photography
Photograph - Digital Capture
This photograph was made just over the Oregon - Washington border looking east. That's Mt. Hood sticking up in the sky above the Columbia river.
The Columbia is the largest river in the Pacific Northwest region of North America. It river rises in the Rocky Mountains of British Columbia, Canada, flowing northwest and then south into Washington, turns west to form most of the border between Washington and Oregon before emptying into the Pacific Ocean. The 1,243 mile long river has its largest tributary in the Snake River. The drainage basin is roughly the size of France and extends into seven U.S. states plus a Canadian province.
By volume, the Columbia is the fourth-largest river in the United States and has the greatest flow of any North American river draining into the Pacific. The river's heavy flow and its relatively steep gradient give it a tremendous potential for the generation of electricity. The 14 hydroelectric dams on the Columbia's main stem and many more on its tributaries produce more hydroelectric power than those of any other river in North America.
The Columbia and its tributaries have been central to the region's culture and economy for thousands of years. Used for transportation since ancient times, they link many cultural groups of the region together. The river system hosts many species of fish that migrate between freshwater habitats and the salty Pacific Ocean. These fish, especially the salmon species, provided the core subsistence for natives; in past centuries, traders from across western North America traveled to the Columbia to bargain for them.
In the late 18th century, a private American ship became the first non-indigenous vessel to enter the river; it was soon followed by a British explorer, who navigated past the Oregon Coast Range into the Willamette Valley. In the following decades, fur trading companies used the Columbia as a key transportation route. Overland explorers entered the Willamette Valley through the scenic but treacherous Columbia River Gorge, and pioneers began to settle the valley in increasing numbers, following both river and land routes to enter it. Steamships along the river linked communities and facilitated trade; the arrival of railroads in the late 19th century, many running along the river, supplemented these links.
Since the late 19th century, public and private sectors have heavily developed the river. This development tamed and harnessed the river, and the results have been massive and multi-faceted. To aid ship and barge navigation, locks were built along the lower Columbia and its tributaries, and dredging operations have opened, maintained, and enlarged the shipping channels. Since the early 20th century, dams were built across the river for the purposes of power generation, navigation, irrigation, and flood control.
Today, a dam-impounded reservoir lies along nearly every mile of the once free-flowing river in the United States, and much of the Canadian stretch has been similarly impounded. Production of nuclear power has taken place at two sites along the river. The plutonium for nuclear weapons was produced for decades at the Washington Hanford Site, which is now the most contaminated nuclear site in the U.S. All these developments have had a tremendous impact on river environments, perhaps most notably through industrial pollution and barriers to fish migration.
The Columbia begins its 1,243-mile journey in a southern Rocky Mountain trench in British Columbia. Columbia Lake, 2,690 feet above sea level, and the adjoining Columbia Wetlands form the river's headwaters. Here, the trench is a broad, deep, and long glacial valley between the Canadian Rockies and the Columbia Mountains in British Columbia. For its first 200 miles, the Columbia flows northwest along the trench through Windermere Lake and the town of Invermere, a region known in British Columbia 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 British Columbia 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 2 miles north of the U.S. - Canada border.
The Columbia then 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 and the western border of the Spokane Indian Reservations. 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 10,000 to 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.
The river then flows past the Gorge Amphitheatre, a prominent concert venue in the Northwest, then through Priest Rapids Dam, and finally 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, and the Columbia makes a sharp bend to the west at the Washington-Oregon border. It defines that border for the final 309 miles of its journey.
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. No other river except for the Klamath completely breaches the Cascades, other rivers that flow through the range also originate in or very near the mountains. The headwaters and upper course of the Pit River flows through much of the Cascades; in contrast the Columbia, it cuts through the range nearly a thousand miles from its source in the Rocky Mountains. The gorge is known for its strong and steady winds, scenic beauty, and its role as an important transportation link. The Columbia then 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. Near Longview, Washington and the Cowlitz River confluence, the river turns west again, emptying 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. Because of the danger and the many shipwrecks near the mouth, it acquired a reputation as the "Graveyard of Ships".
The Columbia drains an area of about 258,000 square miles. Its drainage basin covers nearly all of Idaho, large portions of British Columbia, Oregon, and Washington, ultimately all of Montana west of the Continental Divide, as well as small portions of Wyoming, Utah, and Nevada giving it a total area similar to the size of France. Roughly 745 miles of the river's length and 85 percent of its drainage basin is in the U.S. The Columbia is the twelfth-longest river and has the sixth-largest drainage basin in the entire United States.
In Canada, where the Columbia flows for 498 miles and drains 39,700 square miles, the river ranks 23rd in length, and its basin ranks 13th in size. The Columbia shares its name with nearby places, such as British Columbia, as well as with landforms and bodies of water.
Photograph copyright 2013 Jon Burch Photography
May 9th, 2013
Viewed 91 Times - Last Visitor from Athens, 35 - Greece on 05/02/2015 at 1:27 PM