Download Superstructure, Spring 2010 PDF |
Atkinson Continues I-405 Roadwork in Washington State May 2010 BELLEVUE, Wash. - Drivers traveling through one of the more congested portions of I-405 in Washington state are getting some relief thanks to the Washington State Department of Transportation (WSDOT) and Guy F. Atkinson Construction. In late 2009, Atkinson completed the design-build I-405 South Bellevue Widening project. Over two-and-a-half years, Atkinson's team added two new traffic lanes on I-405 between 112th Avenue and SE Eighth Street as part of the $126 million project. In addition, Atkinson demolished the Wilburton Tunnel, allowing I-405 to expand to six lanes, where the 360-foot tunnel previously restricted traffic flow to four. The project team also built a new southbound bridge over I-90. WSDOT estimates that travel speeds have increased as much as 25 mph since the widening project was completed. Shortly after completing the widening project, the Atkinson team moved north to begin work on a second design-build contract awarded by WSDOT. The $107.5 million I-405/NE Eighth Street to SR 520 Braided Ramps Interchange Improvements project will alleviate congestion along a three-mile stretch near the I-405/SR 520 interchange. Known as "Bellevue Braids" for the crisscrossing ramps that will link the two major highways, the project will improve traffic conditions for the 60,000 drivers who use the interchange en route to Redmond or continue to points north on I-405. Drivers have grown accustomed to vehicles jockeying for position on northbound I-405 approaching SR 520 causing stop-and-go traffic for up to eight hours a day. The Bellevue Braids project replaces a problematic merge with separate, weaving ramps to safely and quickly get drivers to their destinations. Over the next two years, Atkinson will demolish the existing NE 12th Street bridge and replace it with a wider, longer span to allow construction of the new braided ramps. A new ramp will be added from the NE 10th Street Bridge at I-405, giving drivers direct access to SR 520 from downtown Bellevue. In all, Atkinson will build seven new bridges and 30 new retaining walls as part of the project. Jacobs Engineering of Bellevue, Wash., is the lead designer on the project. |