Broadway Bridge (Portland)

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Broadway Bridge

Carries	vehicles and pedestrians
Crosses	Willamette River
Locale	Portland, Oregon
Maintained by	Multnomah County
ID number	06757
Design	Double leaf Rall-type bascule
Longest span	304 feet (92.7 m)
Total length	1,742 (531 m)
Width	70 feet
Vertical clearance	13 feet (3.9 m)
Clearance below	70 ft closed
Opening date	April 22, 1913
Maps and aerial photos Street map from Google Maps or Yahoo! Maps Topographic map from TopoZone Aerial image or topographic map from TerraServer-USA Satellite image from Google Maps or Microsoft Virtual Earth

The Broadway Bridge is a bascule bridge that spans the Willamette River in Portland, Oregon. It was the first bascule bridge built in Portland and the longest in the world at the time of its completion.^[1] It is the longest Rall type bascule bridge still in existence.

The bridge was opened on April 22, 1913 at a cost of $1.6 million. It filled a growing need for a bridge between the St. Johns Bridge at river mile 5.8, and the downtown Steel Bridge at river mile 12.1. Because it was to be the world's largest bascule bridge, there was competition between the patent holders of the Strauss, Scherzer, and Rall type bridges.^[2] The Rall type was selected for the Broadway Bridge because of cost,^[3] but the more complicated rolling lift mechanisms of the Scherzer and Rall types eventually lost favor to the simpler fixed trunnion bascules such as the Chicago and Strauss.

The bridge carries two lanes of vehicle traffic in each direction and has an 11 ft. wide sidewalk on each end. As of 2001 the bridge carried 27,000 vehicles per day and opens for river traffic around 25 times per month. It is also one of the main bridges for bicycle traffic crossing the Willamette in Portland, with over 2,000 daily bicycle crossings.^[4] Its color is "Golden Gate" red.

Because it is such a complicated bridge, there have been frequent repairs to the structure and mechanics of the bridge. In 1948 the concrete deck was replaced with steel grating. During 1982 access for bicyclists was improved by an $18,000 signal and sidewalk upgrade. In order to improve access and reduce energy costs, the sidewalks and lighting were replaced in 2000-2001. ^[5] The Lovejoy Viaduct was removed in 1999 as part of the $10 million construction of the shorter Lovejoy Ramp that opened in September of 2001. A $28 million renovation began in February of 2003. Included in this was the replacement of steel grating with a Fiber-reinforced polymer composite material called DuraSpan, made by Martin Marietta Materials.^[6] The renovation was completed in February of 2005.

[edit] Gallery

HAER discription

West leaf bascule span

Bridge mechanics

[edit] References

^ Smith, Dwight A. (1989). Historic Highway Bridges of Oregon. Oregon Historical Society Press, 116. ISBN 0-87595-205-4.
^ Wood, Sharon (2001). The Portland Bridge Book. Oregon Historical Society. ISBN 0-87595-211-9.
^ Willamette River (Broadway) Bridge (Word). Oregon Department of Transportation. Retrieved on November 6, 2006.
^ BikePortland.org: bridge bike traffic up in '05. Retrieved on April 9, 2006.
^ Broadway Lighting and Sidewalk Project. Multnomah County. Retrieved on November 9, 2006.
^ Martin Marietta Materials (August 20, 2004). Martin Marietta Composites Completes Landmark Installation Of Broadway Bridge Deck. Press release. Retrieved on 2006-11-09.

[edit] External links

	Bridges in the metropolitan area of Portland, Oregon See also: Transportation in Portland, Oregon
	Across the Willamette River (north to south) St. Johns Bridge - Burlington Northern Railroad Bridge 5.1 - Fremont Bridge - Broadway Bridge - Steel Bridge - Burnside Bridge - Morrison Bridge - Hawthorne Bridge - Marquam Bridge - Ross Island Bridge - Sellwood Bridge - Lake Oswego Railroad Bridge - Abernethy Bridge - Oregon City Bridge
	Across the Columbia River (west to east) Burlington Northern Railroad Bridge 9.6 - Interstate Bridge - Glenn L. Jackson Memorial Bridge