A Sightseer's Guide to EngineeringNational Society of Professional EngineersNational Engineer's Week
 


The Evergreen Point Floating Bridge is constructed of 33 prestressed concrete pontoons. A typical pontoon measures 360 feet long, 60 feet wide, and 14 feet, 9 inches deep. The bridge has a retractable drawspan in the middle, and when it opens, the middle pontoons separate and roll underneath the raised sections like drawers.


return to homeback to results    National Society of Professional EngineersNational Engineers Week

© 2010 NSPE. A Sightseer's Guide to Engineering | Disclaimer | Contact: Stacey Ober, pr@nspe.org, at 703-684-2815
WASHINGTON Printable version
Albert D. Rosellini (Evergreen Point) Floating Bridge
State Route 520
Seattle, WA
800/695-7623 or 206/368-4499
Web Site
Drive across the bridge from Seattle to Bellevue, but you'll want to avoid rush hour. 
Hours of Operation: Call the Washington State DOT for bridge closure and repair information. Need a map?
The Evergreen Point Floating Bridge, built 1960-1963, is the longest floating bridge in the world. Essentially a 1.42-mile-long barge, it was an innovative and cost-effective engineering solution to the problem of how to span a lake bed too wide and deep for a suspension bridge. Unfortunately, it has become a victim of its own success. Originally designed to handle a maximum of 50,000 cars a day, it now carries twice that number. The bridge has been reinforced and repaired, but it will likely to be too costly to retrofit the bridge to meet current wind and earthquake standards.
 
Who Made It: Floating structure by Guy F. Atkinson; bridge approach structures by General Construction Company and Manson Construction & Engineering Company