Parsons Brinckerhoff Skagit River Bridge Replacement Pulls Gold Award

Gold Award – Meeting/Exceeding Owner’s/Client’s Needs

Parsons Brinckerhoff – I-5 Skagit River Bridge Replacement

Client: Washington State Department of Transportation

Built in 1955, the Skagit River Bridge crosses the river between Mount Vernon and Burlington in northern Washington State. The bridge is a part of a heavily traveled section of Interstate 5, the primary transportation artery between Seattle and Vancouver, B.C., and an essential corridor for regional and international commerce. On May 23, 2013, an over-height truck clipped a portion of the bridge’s steel truss, causing a 160-foot-long bridge span to collapse into the river.

On June 19, Max J. Kuney Company, with Parsons Brinckerhoff as designer, was selected by the Washington Department of Transportation (WSDOT) and given notice to proceed to construct the $6.87 million permanent bridge span replacement.

Parsons Brinckerhoff utilized its structural engineering familiarity with emergency bridge replacements and design visualization and virtual design and construction capabilities to work closely as part of the design-build team. The team prepared a design and construction scheme that met the WSDOT maximum dead load requirements, minimized impacts to I-5 traffic, was constructible within the 90-day schedule, and resulted in the best value to WSDOT.

The team’s work resulted in three successful and significant first achievements for WSDOT: the first emergency design-build contract using federal funds, the first decked bulb tee girder bridge design on an interstate highway in Washington, and the first use of lightweight aggregate by WSDOT for a concrete girder bridge of this type.

Following a 19-hour closure of I-5, Governor Jay Inslee enthusiastically announced the opening of the new Skagit River Bridge span on Sept. 15, 2013, just 115 days after the initial accident and 88 days after the design-build team’s notice to proceed.