SR 520 Floating Bridge and Landings Design/Build

Seattle, Washington

  • Services Bridge Engineering, Civil Engineering, Structural Engineering, Waterfront Engineering
  • Market(s) Bridges, Floating Structures
  • Awards 2017 ASCE Seattle Section, Local Outstanding Civil Engineering Award for Structures
    2017 ACEC Top Engineering Feat - Grand Conceptor Award
    2017 APWA Top Transportation Project of the Year (over $75M)
    2017 WACA Excellence in Concrete - Public Works, Bridges
    2017 ACEC Gold Award Structural Systems, Engineering Excellence Awards
    2016 DBIA Excellence in Design (Engineering)
    2015 DBIA National Award of Merit
SR 520 Floating Bridge and Landings Design/Build

The SR 520 Floating Bridge and Landings Project designed and built the world’s longest floating bridge, creating a safer, more reliable link between Seattle and the growing high-tech cities east of Lake Washington. With HOV lanes, full shoulders for disabled vehicles, a cross-lake bicycle and pedestrian path, and the largest, heaviest, and strongest bridge pontoons ever built, the new, 1.5-mile-long floating highway dramatically improves the movement of people and freight in the Central Puget Sound region. The Washington State Department of Transportation (WSDOT) considered traditional delivery options but decided that the design-build model was a perfect fit for this project because design-build did several things: it allowed fast-track delivery of the new bridge replacing a vulnerable structure, it allowed greater innovation and potential cost savings to WSDOT, and it shifted appropriate project risk components to the design-builder. KPFF provided prime design, civil, structural, and mechanical engineering services, as well as construction quality assurance management.

SR 520 Floating Bridge and Landings Design/Build

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SR 520 Floating Bridge and Landings Design/Build

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