Steel Bridge

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Steel Bridge
SteelBridgePano1.jpg
Carries Upper: 2 outer traffic lanes and two inner lanes solely for MAX Light Rail
Lower: Union Pacific Railroad (incl. Amtrak toward Eugene) and walkway
Crosses Willamette River
Locale Portland, Oregon
Maintained by Union Pacific Railroad
Design Through truss with a double vertical-lift span
Width 71 feet (22 m)
Longest span 211 feet (64 m)
Clearance below 26 feet (7.9 m) closed, 72 feet (22 m) lower deck raised, 163 feet (50 m) fully raised
Opened 1912 (replaced 1888 bridge)
Coordinates 45°31′40″N 122°40′04″W / 45.52778°N 122.66778°W / 45.52778; -122.66778Coordinates: 45°31′40″N 122°40′04″W / 45.52778°N 122.66778°W / 45.52778; -122.66778

The Steel Bridge is a through truss, double lift bridge across the Willamette River in Portland, Oregon, United States. Its lower deck carries railroad and bicycle/pedestrian traffic, while the upper deck carries road traffic (on the Pacific Highway West No. 1W, former Oregon Route 99W) and light rail (MAX), making the bridge one of the most multimodal in the world. It is the only double-deck bridge with independent lifts in the world[1] 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.

Contents

History [edit]

The bridge was completed in 1912 and replaced the Steel Bridge that was built in 1888 as a double-deck swing-span bridge. The 1888 structure was the first railroad bridge across the Willamette River in Portland. Its name originated because steel, instead of wrought iron, was used in its construction, very unusual for the time.[2] When the current Steel Bridge opened, it was simply given its predecessor's name.

The bridge was designed by the engineering firm of Waddell & Harrington,[3] which was based in Kansas City, Missouri, but also had an office in Portland.[4]:7, 52 The structure was built by Union Pacific Railroad and the Oregon Railway and Navigation Company at a cost of $1.7 million[5] (equivalent to $40 million in 2013[6]). It opened in July 1912 to rail traffic and on August 9, 1912 to automobiles.

The 1888 Steel Bridge (upper deck) had been crossed by horse-drawn streetcars from the time of its opening and then by the city's first electric streetcar line starting in November 1889;[4]:23–25 when the present Steel Bridge opened in 1912, the streetcar lines (all electric by then) moved to it, starting on September 8, 1912.[7] Streetcar service across the Steel continued until August 1, 1948, when the last car lines using it, the Alberta and Broadway Lines, were abandoned. A single line of Portland's once-extensive trolley bus system also used the bridge; the Williams Avenue line crossed the Steel Bridge from February 1937 until October 9, 1949.[4]:31 Many years later, in 1986, electric transit vehicles returned to the bridge in the form of MAX Light Rail and later the Portland Vintage Trolley.[4][8]

In 1950, the Steel Bridge became an important part of a new U.S. 99W highway between Harbor Drive and Interstate Avenue. Harbor Drive was removed in 1974 and replaced with Tom McCall Waterfront Park.

A MAX light rail train crossing the bridge in 2009. TriMet now has four MAX lines, and all of them cross the Steel Bridge.

In the mid-1980s, the bridge underwent a $10 million rehabilitation, including construction of the MAX light rail line of TriMet. The span was closed to all traffic for two years, starting in June 1984.[9] It reopened on May 31, 1986.[10] Completion and testing of the light-rail tracks and overhead wires across the bridge took place during the months that followed, and the light rail line opened for service on September 5, 1986.[4]:37–39

A single-lane viaduct that connected the bridge's east approach to another viaduct (still in existence) that takes traffic from southbound Interstate 5 to Interstate 84 was closed in 1988 and removed in 1989, as part of roadway changes intended to improve traffic flow around the Oregon Convention Center.[11] The center was under construction at that time and opened in 1990.

In 2001, a 220-foot (67 m) long and 8-foot (2.4 m) wide cantilevered walkway was installed on the southern side of the bridge's lower deck as part of the Eastbank Esplanade construction, raising to three the number of publicly accessible walkways across the bridge, including the two narrow sidewalks on the upper deck. The bridge is owned by Union Pacific with the upper deck leased to Oregon Department of Transportation, and subleased to TriMet, while the City of Portland is responsible for the approaches.[12]

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.

In 2012, the Steel Bridge celebrated its 100th birthday. According to The Oregonian, it is the hardest working bridge on the Willamette River: "Cars, trucks, freight trains, buses, Amtrak, MAX, pedestrians, bicycles -- you carry it all."[13]

Structure [edit]

Steel Bridge panorama: at right is the Rose Garden Arena

The lift span of the bridge is 211 feet (64 m) long. At low river levels the lower deck is 26 feet (7.9 m) above the water, and 163 feet (50 m) of vertical clearance is provided when both decks are raised. Because of the independent lifts, the lower deck can be raised to 72 feet (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 buses), 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.[14]

Gallery [edit]

  • HAER description

  • Diagram of lifting mechanism

  • Diagram of lift components

  • The bridge while fully open

  • View from upper sidewalk showing a MAX light rail train above and pedestrian walkway below

  • The Coast Starlight crossing the lower deck

  • Talgo train crossing bridge

See also [edit]

References [edit]

  1. ^ "Willamette River (Steel) Bridge" (DOC). Portland Bridges. Oregon Department of Transportation. 1999. Retrieved 2007-08-25. 
  2. ^ Wood, Sharon (2001). The Portland Bridge Book (2nd Edition). Oregon Historical Society. ISBN 0-87595-211-9. 
  3. ^ Wood Wortman (2006), pp. 5, 39, 42, 180.
  4. ^ a b c d e Sheldrake, Arlen, et al (2012). Steel Over the Willamette. ISBN 978-0-9851207-0-2. 
  5. ^ Smith, Dwight A.; Norman, James B.; Dykman, Pieter T. (1989). Historic Highway Bridges of Oregon. Oregon Historical Society Press. p. 208. ISBN 0-87595-205-4. 
  6. ^ Staff. Consumer Price Index (estimate) 1800–2012. Federal Reserve Bank of Minneapolis. Retrieved March 31, 2013.
  7. ^ "New Bridge Used: Streetcars Take New Route for First Time" (September 9, 1912). The Morning Oregonian, p. 10.
  8. ^ Thompson, Richard H. (2010). Portland's Streetcar Lines. Arcadia Publishing. pp. 71, 90. ISBN 978-0-7385-8126-2. 
  9. ^ "Steel Bridge shut down for light rail" (June 12, 1984). The Oregonian, p. B1.
  10. ^ Federman, Stan (May 30, 1986). "Bridge party trumpets reopening". The Oregonian, p. E2.
  11. ^ Federman, Stan (January 18, 1989). "Major road repairs this summer could snarl Portland-area traffic". The Oregonian, p. B2.
  12. ^ Redden, Jim (October 19, 2006). "Steel Bridge is less than solid". Portland Tribune (Pamplin Media Group). Retrieved November 23, 2012. 
  13. ^ http://blog.oregonlive.com/commuting/2012/07/beaverton_driving_hotline_can.html
  14. ^ "Bridge bike traffic up in '05". BikePortland.org. Retrieved 2006-04-09. 

External links [edit]

Wikimedia Commons has media related to: Steel Bridge
Across the Willamette River
(north to south)
Across the Columbia River
(west to east)
Miscellaneous
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