Columbia Slough

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Coordinates: 45°38′04″N 122°45′36″W / 45.63444, -122.76

Columbia Slough
Slough
Name origin: Columbia River

Country	United States
State	Oregon
County	Multnomah


Source	Fairview Lake (nominal)
- location	Fairview, Multnomah County, Oregon
- elevation	10 ft (3 m) ^[1]
- coordinates	45°33′00″N 122°26′54″W / 45.55, -122.44833 ^[1]
Mouth	Willamette River
- location	Portland, Multnomah County, Oregon
- elevation	10 ft (3 m) ^[2]
- coordinates	45°38′04″N 122°45′36″W / 45.63444, -122.76 ^[2]

Length	19 mi (31 km) ^[3]
Basin	51 sq mi (132 km²) ^[3]
Discharge	for Portland, 0.25 miles (0.40 km) from mouth
- average	104 cu ft/s (2.9 m³/s) ^[4]
- max	2,400 cu ft/s (68 m³/s)
- min	-6,700 cu ft/s (-189.7 m³/s)

Location of the mouth of Columbia Slough in Oregon

The Columbia Slough is a 19-mile (31 km) long, narrow waterway, lying between the Columbia and Willamette rivers in the Portland metropolitan area of the U.S. state of Oregon. Beginning near Fairview Lake, it meanders west through Fairview, Gresham, Maywood Park, and north and northeast Portland to Kelly Point Park, where it enters the Willamette 1.25 miles (2 km) from its confluence with the Columbia.^[3]

The 32,700-acre (132 km²) watershed of the slough includes about 30 miles (48 km) of secondary waterways,^[3] several lakes and ponds, Fairview Creek, and the Smith and Bybee Lakes Wetlands, the largest protected urban wetland in the United States.^[5] About 175 bird species and 26 fish species use the watershed.^[3]

Historically, the Columbia Slough was part of the floodplain near the confluence of the Columbia and Willamette rivers, and floods often altered the wetlands and channels. Artificial levees were built to allow urban development along the slough; the waterway was straightened, and dozens of streams were diverted from natural channels into underground pipes. In 2008, about 158,000 people live in the watershed, which is also home to many industries and businesses, Portland International Airport, and Port of Portland marine terminals.^[3]

In 1978, at the request of Oregon legislators, U.S. Congress stripped the Columbia Slough of its "navigable" status, enabling the land to be dedicated to recreational use, and the cessation of channel dredging. It is an important component of the 40 Mile Loop for several proposed trails and wildlife areas.^[6]

Map of the Columbia Slough's route through Fairview, Gresham, and Portland. The slough begins at Fairview Lake (right) and flows generally west to its confluence with the Willamette River (left). The route has been artificially straightened by orienting each of the panels differently. The compass rose marks north for each. (Zoom in)

[edit] See also

Vanport, Oregon

[edit] References

^ ^a ^b Fairview Lake. Geographic Names Information System. United States Geological Survey (November 28, 1980). Retrieved on 2008-05-25.
^ ^a ^b Columbia Slough. Geographic Names Information System. United States Geological Survey (November 28, 1980). Retrieved on 2008-05-25.
^ ^a ^b ^c ^d ^e ^f Columbia Slough Watershed. Bureau of Environmental Services, City of Portland (2008). Retrieved on 2008-05-23.
^ Note: The average discharge rate was calculated by adding the average annual discharge rates for the four calendar years for which discharge data was available and dividing by 4. According to the USGS, the maximum discharge rate may have been greater December 2–4, 1995, and February 10–14, 1996, and the minimum discharge rate may have been less between November 29 and December 3, 1995, and February 8–9, 1996. USGS 14211820 Columbia Slough at Portland, OR. United States Geological Survey (2008). Retrieved on 2008-05-23.
^ Smith and Bybee Wetlands. Metro (2008). Retrieved on 2008-05-23.
^ Charles E. Little (1990). Greenways for America. JHU Press, 78. ISBN 0801851408. Retrieved on 2008-06-01.