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The Fremont Bridge is a steel tied-arch bridge over the Willamette River located in Portland, Oregon. It carries Interstate 405 traffic between downtown and North Portland where it intersects with Interstate 5. It has the longest main span of any bridge in Oregon and, until the completion of the Caiyuanba Bridge, is the longest tied-arch bridge in the world.
Due to the public's dissatisfaction with the appearance of the Marquam Bridge, the Portland Art Commission was invited to participate in the design process of the Fremont. The improvement in visual quality resulted in a bridge that was nearly 6 times as expensive as the purposefully economical Marquam Bridge.
In October of 1971, while still under construction, a crack was found on the west span girder that requred a $5.5 million redesign and repair.
The main span of the bridge was built in California then assembled (http://www.portlandonline.com/auditor/index.cfm?&a=ceici&c=27928) at Swan Island and floated in place on a barge. On March 16, 1973 the 6,000 ton steel arch span was lifted 170 ft. using 32 hydraulic jacks. At the time, it was listed in the Guiness Book of World Records as the heaviest lift ever completed. The bridge was open on November 11, 1973 at a final cost of $82 million, most of which was financed by the Federal Highway Administration.
The bridge is 2,152 ft. in total length with a main span of 1,255 ft. The top of the arch is 381 ft. tall and the main span has 175 ft. of vertical clearance. It was named for Fremont Street, which was a proposed eastside approach. Designers modeled the bridge after the Port Mann Bridge in Vancouver, British Columbia.
The Fremont Bridge was also the 26th Peregrine falcon nest site designated in Oregon after the raptor was placed on the U.S. Threatened and Endangered Species list in 1970.
External links
Books
Wood, Sharon. The Portland Bridge Book. Portland: Oregon Historical Society, 2001. ISBN 0-87595-211-9.
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