Willamette River
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The Willamette River (pronounced "wil-LAM-met") is a tributary of the Columbia River, approximately 240 mi (386 km) long, in northwestern Oregon in the United States. Flowing northward between the Coastal Range and Cascade Range, the river and its tributaries form a basin called the Willamette Valley containing the largest population centers of Oregon, including Portland, which sits along both sides of the river near its mouth on the Columbia. Its lush valley is fed by prolific rainfall on the western side of the Cascades, forming one of the most fertile agricultural regions of North America that was the destination for many if not most of the emigrants along the Oregon Trail. The river was an important transportation route throughout much of the early history of the state, furnishing a means of conveying the vast timber and agricultural resources of the state to the outside world.
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Description
The Willamette rises in three separate forks in the mountains south and southeast of Eugene, at the southern end of the Willamette Valley. The Middle Fork and North Fork rise on the western side of the Cascades between Three Sisters south to Diamond Peak, with the Middle Fork receiving the North Fork northwest of Oakridge and flowing northwest through the mountains to the southern end of the Willamette Valley. The Coast Fork rises in the lower mountains south of Cottage Grove, flowing north to join the Middle Fork 2 mi (3.2 km) southeast of Eugene.
From Eugene, the combined river flows NNW across the plain of the southern Willamette Valley to Corvallis, then follows a zigzag course past Albany and around the isolated hills in the central valley, passing west of downtown Salem. From Salem it flows north in a meandering course across the northwest plain of the valley, reaching the hills at Newberg, where it turns sharply ENE along the hills, passing through an opening in the hills at Oregon City, the location of the Falls of the Willamette and the head of navigation. From Oregon City it flows northwest, past Lake Oswego and Milwaukie on the south edge of Portland, then passing between east and west Portland, where it is spanned by a series of urban bridges. Downstream of downtown Portland it flows northwest through the industrial port area of Portland Harbor, then splitting into two channels around Sauvie Island, both of which hook around to enter the Columbia from the west, with the main channel entering on the north edge of Portland and the smaller Multnomah Channel entering approximately 15 mi (24 km) NNW at St.Helens.
The river's many tributaries drain the surrounding valley and well as portions of the Cascades and the Coastal Range. Downstream from the confluence of its forks, it is joined by McKenzie on the north side of Eugene, and by the Long Tom River from the southwest approximately 10 mi (16 km) south of Corvallis. It is joined by the Calapooia from the southeast 5 mi (8 km) northeast of Corvallis. It is joined by the Santiam from the east and the Luckiamute from the west within 1 mi (1.6 km) of each other approximately 5 mi (8 km) north of Albany. It is joined by the Yamhill from the west at Dayton, by the Molalla from the southeast near Canby, by the Tualatin from the west at West Linn, and by the Clackamas from the southeast at Gladstone.
The river forms part of the boundary of the following counties: Benton, Linn, Polk, Marion, Yamhill and Clackamas. Tributaries of the Willamette River also drain some or all of Lane, Washington and Multnomah counties.
Although riverboats navigated the upstream part of the Willamette into the first decades of the 20th century, currently there is no commercial traffic on the river above the Willamette Falls. The Willamette Falls Locks allow boat traffic, primarily recreational vessles, around the falls. The river is crossed by serveral ferries along its route in the Willamette Valley.
Environmental issues
The Portland Harbor section of the Willamette River between downtown Portland and its terminus at the Columbia River is heavily polluted from years of industrial development of the river and its banks. Historical and current activities have included shipbuilding, creosote manufacture, and transfer and storage of petroleum products. State studies in the 1990s identified a wide variety of pollutants in the river bottom, including heavy metals, polychlorinated biphenyls (PCBs), and pesticides. As a result of these studies, this section of the river was designated a Superfund site in 2000, involving the federal Environmental Protection Agency in cleanup of the river bottom. As of 2005, cleanup and containment of the pollutants is underway and is expected to be completed by 2006.
See also
External links
- Portland Harbor DEQ cleanup (http://www.deq.state.or.us/nwr/PortlandHarbor/ph.htm) - Oregon state Department of Environmental Quality