Steel Bridge

Infobox_Bridge
bridge_name=Steel Bridge


carries=upper: 2 outer traffic lanes and two inner lanes solely for MAX Light Rail
lower: Union Pacific Railroad (incl. Amtrak) and walkway
crosses=Willamette River
locale=Portland, Oregon
maint=Union Pacific Railroad
design=Through truss with a double vertical lift span
mainspan=211 ft (64 m)
width=71 ft (22 m)
below=26 ft (8 m) closed, 72 ft (22 m) lower deck raised, 163 ft (50 m) fully raised
open=1912 (replaced 1888 bridge)
lat=45.52778
long=-122.66778

The Steel Bridge is a through truss, double lift bridge across the Willamette River in Portland, Oregon, United States. It carries railroad and bicycle/pedestrian traffic on the lower deck, and the Pacific Highway West No. 1W (former Oregon Route 99W), MAX Light Rail and a vintage streetcar on the upper deck, making it one of the most multimodal in the world. It is the only double-deck bridge with independent lifts in the world [cite web
url = http://egov.oregon.gov/ODOT/HWY/GEOENVIRONMENTAL/docs/Historic_Bridge/Willamette_Steel_Bridge.doc
title = Willamette River (Steel) Bridge
accessdate = 2007-08-25
year = 1999
format = DOC
work = Portland Bridges
publisher=Oregon Department of Transportation ] and the second oldest vertical lift bridge in North America, after the nearby Hawthorne Bridge. The bridge links the Rose Quarter and Lloyd District in the east to Old Town Chinatown neighborhood in the west.

History

The bridge was completed in 1912 and replaced the Steel Bridge that was built in 1888 as a double deck swing span bridge ( [http://shastaroute.railfan.net/Cards/SteelBr1.jpgphoto] ). It was the first railroad bridge across the Willamette River in Portland. The name originated because steel, instead of wrought iron, was used in its construction. [ cite book
last= Wood
first= Sharon
title = The Portland Bridge Book
publisher = Oregon Historical Society
date = 2001
id= ISBN 0-87595-211-9]

The structure was built by Union Pacific Railroad and the Oregon Railway and Navigation Company at a cost of $1.7 million. [cite book
first = Dwight A.
last= Smith
coauthors = Norman, James B.; Dykman, Pieter T.
title = Historic Highway Bridges of Oregon
publisher = Oregon Historical Society Press
date = 1989
pages = 208
id = ISBN 0-87595-205-4 ] It opened in July of 1912 to rail traffic and on August 9,1912 to automobiles. Between 1984 and 1986 the bridge underwent a $10 million rehabilitation including MAX construction.

In 2001, a 220 ft (67 m) long and 8 ft (2.5 m) wide cantilevered walkway was installed on the southern side of the bridge's lower deck as part of the Eastbank Esplanade construction, making a total of three publicly accessible walkways, including two narrow sidewalks on the upper deck. The bridge is currently owned by Union Pacific with the upper deck leased to Oregon Department of Transportation, and subleased to TriMet, although the City of Portland is responsible for the approaches. [ cite news
last = Redden
first = Jim
publisher = Portland Tribune
title = Steel Bridge is less than solid
date = October 19,2006
url = http://www.portlandtribune.com/news/story.php?story_id=116130352598560300
accessdate = 2006-11-06 ]

The upper deck was closed again for summer 2008 for maintenance and to allow a junction to be built at the west end for the MAX Green Line. The lower deck of the bridge was threatened by major floods in 1948, 1964, and 1996.

tructure

The lift span of the bridge is 211 ft (64 m) long. At low river levels the lower deck is 26 ft (7.9 m) above the water and 163 ft (50 m) of vertical clearance is provided when both are raised. Because of the independent lifts, the lower deck can be raised to 72 ft (22 m), telescoping into the upper deck but not disturbing it. Each deck has it own counterweights, two for the upper and eight for the lower, totaling 9,000,000 lb (4,100 metric tons).

The machinery house is above the upper deck lift span with an operator's room suspended below the house so that the operator can view river traffic as well as the upper deck. The average daily traffic in 2000 was 23,100 vehicles (including many TriMet bus lines), 200 MAX trains, 40 freight and Amtrak trains, and 500 bicycles. The construction of the lower deck walkway connected to the Eastbank Esplanade resulted in a sharp increase in bicycle traffic, with over 2,100 daily bicycle crossings in 2005. [ cite web
publisher = BikePortland.org
url = http://bikeportland.org/2005/09/20/bridge-bike-traffic-jumps-15-in-05/
title = Bridge bike traffic up in '05
accessdate = 2006-04-09 ]

Gallery

ee also

* List of crossings of the Willamette River

References

External links

* [http://egov.oregon.gov/ODOT/HWY/GEOENVIRONMENTAL/historic_bridges_Portland.shtml#Steel_Bridge ODOT Steel Bridge page]
*
* [http://memory.loc.gov/cgi-bin/query/r?ammem/hh:@field(DOCID+@lit(OR0291)) The Library of Congress: American Memory]

Crossings navbox
structure = Crossings
place = Willamette River
bridge = Steel Bridge
bridge signs =
upstream = Burnside Bridge
upstream signs =
downstream = Broadway Bridge
downstream signs =