The Willamette River (pronounced wɨˈlæmɨt (help·info)) is a tributary A tributary is a stream or river which flows into a mainstem river. A tributary does not flow directly into a sea. Tributaries and the mainstem river serve to drain the surrounding drainage basin of its surface water and groundwater by leading the water out into an ocean or some other large body of water of the Columbia River The Columbia River is the largest river in the Pacific Northwest region of North America. It is named after the Columbia Rediviva, the first ship from the western world known to have traveled up the river. It stretches from British Columbia through Washington state, forming much of the border between Washington and Oregon before emptying into the. The name derives from a similar Clackamas Indian village name.[1] The river is 187 miles (301 km) long, lying entirely in northwestern Oregon Oregon (pronounced /ˈɔərɨɡən/ OR-i-gən) is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern boundaries in the United States The United States of America is a federal constitutional republic comprising fifty states and a federal district. The country is situated mostly in central North America, where its forty-eight contiguous states and Washington, D.C., the capital district, lie between the Pacific and Atlantic Oceans, bordered by Canada to the north and Mexico to the.[3] Flowing northward between the Oregon Coast Range and Cascade Range The Cascade Range is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, and the notable volcanoes known as the High Cascades. The small part of the range in British Columbia is called the, the river and its tributaries form a basin called the Willamette Valley The Willamette Valley is the region in northwest Oregon in the United States that surrounds the Willamette River as it proceeds northward from its emergence from mountains near Eugene to its confluence with the Columbia River at Portland. A small part of the Willamette Valley ecoregion is in southwestern Washington, around the city of Vancouver containing two-thirds of Oregon's population,[6] including its largest city Portland Portland is a city located in the Northwestern United States, near the confluence of the Willamette and Columbia rivers in the state of Oregon. As of July 2008, it has an estimated population of 575,930, making it the thirtieth most populous in the United States. It has been referred to as the greenest city in the United States. Portland is Oregon', which sits along both sides of the river near its mouth on the Columbia (the river divides the east and west sides of the city). Its lush valley is fed by prolific rainfall on the western side of the Cascades, forming one of the most fertile agricultural Agriculture refers to the production of food and goods through farming and forestry. Agriculture was the key development that led to the rise of civilization, with the husbandry of domesticated animals and plants creating food surpluses that enabled the development of more densely populated and stratified societies. The study of agriculture is regions of North America North America is the northern continent of the Americas, situated in the Earth's northern hemisphere and almost totally in the western hemisphere. It is bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the southeast by the Caribbean Sea, and on the west by the North Pacific Ocean; South America lies to the that was the destination for many if not most of the immigrants along the Oregon Trail The Oregon Trail was one of the main serious overland migration routes on the North American continent, leading from locations on the Missouri River to the Oregon Territory. The eastern half of the trail was also used by travelers on the California Trail, Bozeman Trail, and Mormon Trail which used much of the same trail before turning off to their. 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.

In Harrisburg, the average depth of river is approximately 20 feet (6.1 m) and 50 feet (15 m) maximum river depth. In Portland Portland is a city located in the Northwestern United States, near the confluence of the Willamette and Columbia rivers in the state of Oregon. As of July 2008, it has an estimated population of 575,930, making it the thirtieth most populous in the United States. It has been referred to as the greenest city in the United States. Portland is Oregon', the average depth of river is 65 feet (20 m) and maximum depth of river is 130 feet (40 m).[citation needed]

Part of the river's floodplain A floodplain, or flood plain, is flat or nearly flat land adjacent to a stream or river that experiences occasional or periodic flooding. It includes the floodway, which consists of the stream channel and adjacent areas that carry flood flows, and the flood fringe, which are areas covered by the flood, but which do not experience a strong current (the Willamette Floodplain) was established as a National Natural Landmark The National Natural Landmark program recognizes and encourages the conservation of outstanding examples of the United States' natural history. It is the only natural areas program of national scope that identifies and recognizes the best examples of biological and geological features in both public and private ownership. The program was in 1987; ten years later the river was named as one of ten national American Heritage Rivers American Heritage Rivers are designated by the United States Environmental Protection Agency to receive special attention to further three objectives: natural resource and environmental protection, economic revitalization, and historic and cultural preservation.

Contents

Description

The Willamette rises in three separate forks in the mountains south and southeast of Eugene Eugene is the second largest city in the U.S. State of Oregon and the county seat of Lane County. It is located at the south end of the Willamette Valley, at the confluence of the McKenzie and Willamette rivers, about 50 miles (86 km) east of the Oregon Coast. According to the official 2008 population figures Eugene is the second largest city in, 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 The Three Sisters are three volcanic peaks of the Cascade Volcanic Arc and the Cascade Range in Oregon, each of which exceed 10,000 feet in elevation. They are the third, fourth, and fifth highest peaks in the state of Oregon and are located in the Three Sisters Wilderness, about 15 mi (24 km) southwest from the nearest town of Sisters, Oregon south to Diamond Peak. The Middle Fork receives the North Fork northwest of Oakridge and flows 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 miles (3.2 km) southeast of Eugene.

Map of the Willamette River watershed

From Eugene, the combined river flows north-northwest across the plain of the southern Willamette Valley The Willamette Valley is the region in northwest Oregon in the United States that surrounds the Willamette River as it proceeds northward from its emergence from mountains near Eugene to its confluence with the Columbia River at Portland. A small part of the Willamette Valley ecoregion is in southwestern Washington, around the city of Vancouver to Corvallis Corvallis is a city located in central western Oregon, United States. It is the county seat of Benton County and the principal city of the "Corvallis, Oregon Metropolitan Statistical Area", which encompasses all of Benton County. The population was estimated at 49,807 in 2006 by the United States Census Bureau,, though other research, then follows a zigzag course past Albany Albany is a city in Benton and Linn Counties in the western part of the U.S. state of Oregon. It is located in the Willamette Valley and is the county seat of Linn County. As of the 2000 census, the city population was 40,852. As of 2007, Albany was the 11th largest city in Oregon. The unofficial estimated population was 48,770 in 2008 and around the isolated hills in the central valley, passing west of downtown Salem Salem is the capital of the U.S. state of Oregon, and the county seat of Marion County. It is located in the center of the Willamette Valley alongside the Willamette River, which runs north through the city. The river forms the boundary between Marion and Polk counties, and the city neighborhood of West Salem is in Polk County. Salem was founded. From Salem it flows north in a meandering A meander in general is a bend in a sinuous watercourse. A meander is formed when the moving water in a river erodes the outer banks and widens its valley. A stream of any volume may assume a meandering course, alternatively eroding sediments from the outside of a bend and depositing them on the inside. The result is a snaking pattern as the course across the northwest plain of the valley, reaching the hills at Newberg Newberg is a city in Yamhill County, Oregon, United States. Located in the Portland metropolitan area, the city is home to George Fox University. As of the 2000 census, the city population was 18,064. The 2007 estimate is 21,675 residents and is the second most populous city in the county, where it turns sharply east-northeast along the hills, passing through an opening in the hills at Oregon City Oregon City was the first city in the United States west of the Rocky Mountains to be incorporated. It is the county seat of Clackamas County, Oregon. As of the 2000 census, the city population was 25,754; the 2006 estimate has the population at 29,540, the location of the Willamette Falls and the de facto 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 splits into two channels around Sauvie Island that both hook around to enter the Columbia from the west. The main channel enters on the north edge of Portland, and the smaller Multnomah Channel enters about 15 miles (24 km) to the north-northwest at St. Helens.

Tributaries of the Willamette River

The river's many tributaries drain the surrounding valley as 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 miles (16 km) south of Corvallis. It is joined by the Marys from the west at Corvallis, and the Calapooia from the southeast 5 miles (8.0 km) northeast of Corvallis, and it is joined by the Santiam from the east and the Luckiamute from the west within 1 mile (1.6 km) of each other approximately 5 miles (8.0 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 Benton County is a county located in the U.S. state of Oregon. The county was named after Thomas Hart Benton, a U.S. senator who advocated U.S. control over the Oregon Country. In 2000, the county's population was 78,153. It is coextensive with the Corvallis Metropolitan Statistical Area. Its county seat is Corvallis, Linn Linn County is a county located in the U.S. state of Oregon. It is named in honor of Lewis F. Linn, a U.S. Senator from Missouri who advocated the American occupation of the Oregon Country. In 2000, its population was 103,069. The seat of the county is Albany, Polk, Marion, Yamhill Yamhill County is a county located in the U.S. state of Oregon. According to Oregon Geographic Names, the origin of the name is uncertain, but is probably from an explorer's name for a local Native American tribe, the Yamhill, who are part of the North Kalapuyan family. The population of Yamhill County was 84,992 in the 2000 census. The county and Clackamas. Tributaries of the Willamette River also drain some or all of Lane Lane County is a county in the U.S. state of Oregon. In 2000, its population was 322,959. It is named in honor of Joseph Lane, Oregon's first territorial governor. The seat of the county is Eugene, Washington Washington County is one of 36 counties in the U.S. state of Oregon. Originally named Twality in 1843, the territorial legislature renamed it for the first president of the United States, George Washington, in 1849. In 2000 census, its population was 445,342. The seat and largest city is Hillsboro and Multnomah counties.

Although riverboats A riverboat is a ship designed for inland navigation. These vessels are usually less sturdy than ships built for the open seas, with limited navigational and rescue equipment, as they do not have to survive the high winds or large waves characteristic on large lakes, seas or oceans. They can therefore be build from steel as well as from composite navigated the upstream part of the Willamette into the first decades of the 20th century, currently there is little commercial traffic on the river above the Willamette Falls. The Willamette Falls Locks allow boat traffic, primarily recreational vessels, around the falls. The river is crossed by three ferries along its route in the Willamette Valley. The three ferries are located (from south to north) at Buena Vista, Wheatland, and Canby. The only locks on the river are located at Oregon City. There are 34 named river bars A shoal, sandbar , or sandbank is a somewhat linear landform within or extending into a body of water, typically composed of sand, silt or small pebbles. A spit or sandspit is a type of shoal. Shoals are characteristically long and narrow (linear) and develop where a stream or ocean current promotes deposition of granular material, resulting in in the Willamette between Newberg and Salem.[7]

The Willamette River is prone to periodic floods. The great winter flood of 1861 destroyed several towns, including Linn City, Champoeg, and Scottsburg. The flood of 1894 seems to be the first flood well documented with photographs: one such famous picture depicts men thigh-deep in water in downtown Portland, pointing shotguns at decoy ducks as they float by in the flood waters. The great Vanport Flood of 1948 wiped Oregon's then second-largest city off the map. It was a WWII-era project city, built to temporarily house shipyard workers. The city stood near the confluence of the Willamette and Columbia Rivers, a spot later occupied by Portland International Raceway. Other notable floods include events in 1899, 1964, and the Willamette Valley Flood of 1996.

The Willamette River at Harrisburg

The river below Willamette Falls (RM 26.5) is subject to semidiurnal tides Tides are the rising of Earth's ocean surface caused by the tidal forces of the Moon and the Sun acting on the oceans. Tides cause changes in the depth of the marine and estuarine water bodies and produce oscillating currents known as tidal streams, making prediction of tides important for coastal navigation . The strip of seashore that is caused by the Pacific Ocean The Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Mare Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan. It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and Australia in the west, and the Americas in the,[8] but also with the effects of dams on the Columbia River The Columbia River is the largest river in the Pacific Northwest region of North America. It is named after the Columbia Rediviva, the first ship from the western world known to have traveled up the river. It stretches from British Columbia through Washington state, forming much of the border between Washington and Oregon before emptying into the and Willamette river basin which are regulated for hydroelectric Hydroelectricity is electricity generated by hydropower, i.e., the production of power through use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy. Once a hydroelectric complex is constructed, the project produces no direct waste, and has a considerably lower output level of the power generation. Reverse flow is regularly observed above Ross Island at (river mile 15).[9]

The lower river flow rate varies considerably by season and due to weather. Warm winter rains, for example, cause extensive mountain snow melt which significantly raises the river level and flow rate. The Willamette Valley Flood of 1996 was an extreme combination of saturated ground, snow melt and heavy rain. The maximum flow rate is not known, however 283,000 cubic feet per second (8010 m³/s) was estimated on January 18, 1974 at river stage 23.84 feet (7.27 m). The peak river stage (measured at the Morrison Bridge gauge in downtown Portland) on February 9, 1996, was 27.74 feet (8.46 m). Flood A flood is an overflow or accumulation of an expanse of water that submerges land. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Flooding may result from the volume of water within a body of water, such as a river or lake, which overflows or breaks levies, with the result that some of the water stage is 18.0 feet (5.5 m). The other extreme occurred during a drought on July 10, 1978, at 4,200 cu ft/s (120 m³/s).[4] The Willamette's mean discharge rate is approximately 32,000 cu ft/s (910 m3/s).[10]

Environmental issues

Since as early as 1869, with the introduction of a federally-funded "snag puller" designed to keep the waterway clear, human habitation has had an impact on the ecology of the river basin.[11] The construction of big federal dams on the Willamette's tributaries between 1941 and 1969 impacted the spawning grounds for spring Chinook salmon and steelhead trout.[11] Domestic and industrial waste from the cities built up along the river were said to have turned the river, essentially, into an open sewer by the 1920s.[11]

A 1927 Portland City Club report labeled the waterway "filthy and ugly," and identified the City of Portland as the worst offender.[11] The Oregon Anti-Stream Pollution League brought pollution-abatement measure before the 1937 Oregon Legislature; the bill passed, but Governor Charles Martin vetoed it. The Izaak Walton League and the Oregon Wildlife Federation countered the governor's veto with a ballot initiative, the Water Purification and Prevention of Pollution bill, which passed in November 1938.[11]

Today, 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 include shipbuilding Shipbuilding is the construction of ships. It normally takes place in a specialized facility known as a shipyard. Shipbuilders, also called shipwrights, follow a specialized occupation that traces its roots to before recorded history, creosote Creosote is the name used for a variety of products including wood creosote and coal tar creosote. Wood creosote is created by high temperature treatment of beech and other woods, or from the resin of the Creosote bush manufacture, lead Lead is a main-group element with symbol Pb (Latin: plumbum) and atomic number 82. Lead is a soft, malleable poor metal, also considered to be one of the heavy metals. Lead has a bluish-white color when freshly cut, but tarnishes to a dull grayish color when exposed to air. It has a shiny chrome-silver luster when melted into a liquid processing, and transfer and storage of petroleum Petroleum or crude oil is a naturally occurring, flammable liquid found in rock formations in the Earth consisting of a complex mixture of hydrocarbons of various molecular weights, plus other organic compounds products. State studies in the 1990s identified a wide variety of pollutants in the river bottom, including heavy metals, polychlorinated biphenyls Polychlorinated biphenyls are a class of organic compounds with 1 to 10 chlorine atoms attached to biphenyl, which is a molecule composed of two benzene rings. The chemical formula for PCBs is C12H10-xClx, where x > 1. PCB's were widely used for many applications, especially as dielectric fluids in transformers and capacitors and coolants. Due (PCBs), and pesticides A pesticide is a substance or mixture of substances used to kill a pest. A pesticide is any substance or mixture of substance intended for: - preventing, destroying, repelling or mitigating any pest. A pesticide may be a chemical substance, biological agent , antimicrobial, disinfectant or device used against any pest. Pests include insects, plant. As a result of these studies, this section of the river was designated a Superfund Superfund is the common name for the Comprehensive Environmental Response, Compensation, and Liability Act , a United States federal law designed to clean up abandoned hazardous waste sites. Superfund provides broad federal authority to clean up releases or threatened releases of hazardous substances that may endanger public health or the site in 2000,[12] involving the United States Environmental Protection Agency The U.S. Environmental Protection Agency is an agency of the federal government of the United States charged to regulate chemicals and protect human health by safeguarding the natural environment: air, water, and land. The EPA was proposed by President Richard Nixon and began operation on December 2, 1970, when its establishment was passed by in cleanup of the river bottom.[13] The initial cleanup and containment of the pollutants is focused on the portion between Swan Island and Sauvie Island.[14]

The Superfund site is downstream from most of the river however and lies less than twelve miles from where the Willamette ends at the Columbia river. Further upstream the pressing environmental issues have been mainly variations in pH and dissolved oxygen.[15] In the Portland Metropolitan Area, these issues are exacerbated by sewer overflow events during periods of high rainfall. The city has embarked on expanding the sewer system in order to minimize these events through construction of the Big Pipe Project part of the river renaissance project.

Even further upstream however, the Willamette is not heavily polluted and is used by communities, such as the City of Tigard Tigard is a city in Washington County, Oregon, United States. The population was 41,223 at the 2000 census. The 2006 estimate is 46,300 residents. According to the 2003 Oregon Blue Book, Tigard is the state's 11th largest city. Located south of Beaverton and north of Tualatin, it is part of the Portland metropolitan area, for drinking water. The major contaminants are from agricultural runoff.

Big Pipe Project

Following an agreement between the City of Portland and the State of Oregon to reduce Combined sewer overflows (CSOs) dramatically in 1991,[16] the Bureau of Environmental Services began work on what it dubbed the "Big Pipe Project".

The project consisted primarily of two large pipes on either side of the river. The project was part of a larger effort by the Bureau of Environmental Services to reduce CSOs through a series of combined efforts, which had already netted results of a 53 percent reduction in CSO volume by 2003.[16]

The west side pipe, which is approximately 14 feet (4.3 m) in diameter and travels from Southwest Clay Street to the Swan Island Pumping Station, was completed in 2006.[16][17] The pipe connects to the Southwest Parallel Interceptor, another pipe project approximately 6 feet (1.8 m) in diameter, at Southwest Clay Street, which continues south for several more miles, covering the Portland Metro South Waterfront area.

As of June 2008, the east side pipe is under construction and is slated for completion in December 2011.[18] The pipe, like its cousin, will connect to the Swan Island Pumping Station but will extend a full 6 miles (9.7 km) south down the east bank.[19] The east side pipe, serving a much larger segment of population, is 22 feet (6.7 m) wide and will be able to hold more than 83 million gallons (310 million L The litre or liter is a unit of volume. There are two official symbols: the Latin letter L in lower and upper case (l and L). The lower case L is also often written as a cursive ℓ, though this symbol has no official approval by any international bureau. Although the litre is not an SI unit, it is accepted for use with the SI, and has appeared in) of storm water and sewage.[18][19]

Together the pipes and other CSO projects will provide a 94 percent reduction in CSO volume by 2011, dramatically reducing one of the largest pollutants of the Willamette River.[18][19]

The Willamette River as it passes through Portland, Oregon

See also

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References

  1. ^ a b Bright, William (2004). Native American Placenames of the United States. Norman, Oklahoma: University of Oklahoma Press. pp. 567. ISBN 9780806135984.
  2. ^ a b c d "Willamette River". Geographic Names Information System The Geographic Names Information System is a database that contains name and locative information about more than two million physical and cultural features located throughout the United States of America and its territories. It is a type of gazetteer. GNIS was developed by the United States Geological Survey in cooperation with the United States (GNIS). United States Geological Survey The United States Geological Survey is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization has four major science disciplines, concerning biology, geography, geology, and hydrology. The USGS is a (USGS). November 28, 1980. http://geonames.usgs.gov/pls/gnispublic/f?p=gnispq:3:::NO::P3_FID:1158060. Retrieved on 2008-07-06. Source elevation derived from Google Earth Google Earth is a virtual globe, map and geographic information program that was originally called Earth Viewer, and was created by Keyhole, Inc, a company acquired by Google in 2004. It maps the Earth by the superimposition of images obtained from satellite imagery, aerial photography and GIS 3D globe. It is available under three different search using GNIS source coordinates.
  3. ^ a b "The River". Willamette Riverkeeper. http://www.willamette-riverkeeper.org/nww1.htm. Retrieved on 2008-07-06.
  4. ^ a b c "National Water Information System: USGS 14211720 Willamette River at Portland". United States Geological Survey. 2008. http://waterdata.usgs.gov/or/nwis/uv/?site_no=14211720&PARAmeter_cd=00065,00060. Retrieved on 2008-07-06.
  5. ^ Loy, Willam G.; Stuart Allan, Aileen R. Buckley, James E. Meecham (2001). Atlas of Oregon. University of Oregon Press. pp. 164–65. ISBN 0-87114-102-7.
  6. ^ "Willamette Basin Alternative Futures Analysis" (PDF). U.S. Environmental Protection Agency. August, 2002. http://www.epa.gov/wed/pages/projects/alternativefutures/twopager.pdf. Retrieved on 2006-11-16.
  7. ^ "Oregon USGS bars plotted on Google Map of central Willamette valley". USGS. http://maps.google.com/maps?q=http:%2F%2Ftoolserver.org%2F~para%2Fcgi-bin%2Fkmlexport%3Farticle%3DList_of_shoals_of_Oregon&ie=UTF8&ll=45.074006,-122.99263&spn=0.220873,0.549316&t=h&z=12. Retrieved on 2008-12-22.
  8. ^ "Tidally-Influenced Waterways". Public Ownership of Submerged and Submersible Land. State of Oregon. http://www.oregon.gov/DSL/NAV/tidally.shtml. Retrieved on 2008-07-31.
  9. ^ Caldwell, James M.; Micelis C. Doyle. "Sediment Oxygen Demand in the Lower Willamette River, Oregon, 1994" (PDF). Oregon Department of Environmental Quality. 4. http://or.water.usgs.gov/pubs_dir/Pdf/95-4196.pdf. Retrieved on 2006-11-16.
  10. ^ "Willamette River Info.". Willamette Riverkeeper. http://www.willamette-riverkeeper.org/river1.htm. Retrieved on 2007-07-02.
  11. ^ a b c d e Willamette River in the Oregon Encyclopedia
  12. ^ Lee van der Voo (July 3, 2007). "History of a Superfund cleanup bid". Portland Tribune. http://portlandtribune.com/news/story.php?story_id=118341365933266700. Retrieved on 2008-02-12.
  13. ^ "Portland Harbor Superfund Site". Oregon Department of Environmental Quality. http://web.archive.org/web/20061216212032/http://www.deq.state.or.us/nwr/PortlandHarbor/ph.htm. Retrieved on 2006-12-16.
  14. ^ "Region 10 Cleanup: Portland Harbor". United States Environmental Protection Agency. http://yosemite.epa.gov/r10/cleanup.nsf/sites/ptldharbor. Retrieved on 2008-02-12.
  15. ^ "Processes Controlling Dissolved Oxygen and pH in the Upper Willamette River Basin" (PDF). U.S. Geological Survey. 1994. http://or.water.usgs.gov/pubs_dir/Pdf/95-4205.pdf. Retrieved on 2008-02-12.
  16. ^ a b c "Northwest Construction". http://northwest.construction.com/features/archive/0311_Cover.asp. Retrieved on 2008-06-03.
  17. ^ "West Side CSO Tunnel Project". http://www.portlandonline.com/cso/index.cfm?c=30909. Retrieved on 2008-06-03.
  18. ^ a b c "East Side CSO Tunnel Project". http://www.portlandonline.com/cso/index.cfm?c=31727. Retrieved on 2008-06-03.
  19. ^ a b c "A big pipe". The Oregonian. 2007-12-11.

External links

American Heritage Rivers
Rivers Blackstone & Woonasquatucket • Connecticut • Cuyahoga • Detroit • Hanalei • Hudson • Lower Mississippi • Potomac • New • Rio Grande • St. Johns • Upper Mississippi • Upper Susquehanna & Lackawanna • Willamette

Categories: American Heritage Rivers | Rivers of Oregon | Willamette River | Tributaries of the Columbia River

 

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