SR 99 - NB Duwamish River Bridge - Select Grid Deck Replacement

Project news

  • Construction started July 26, 2020. Expect nightly closures Sundays through Thursdays on northbound SR 99 through mid-August and plan for detours.
  • While the SR 99 Duwamish River Bridge is closed at night, the Spokane Street (lower) Bridge is open to all traffic overnight only.
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Needs and benefits

Several of the panels that make up the deck of the northbound SR 99 Duwamish River Bridge, commonly known as the 1st Avenue South bridge, need to be replaced to keep the bridge in a state of good repair. This highway is a critical route between cities like Burien, Normandy Park and SeaTac, and Sea-Tac Airport toSeattle, carrying about 62,000 vehicles each day.

During summer 2020, WSDOT contractor crews will replace 14 grid deck panels on the northbound SR 99 Duwamish River Bridge. This will help increase traction on the bridge and provide a smoother, safer ride for travelers. Also, replacing the grid deck panels helps preserve the bridge structure and reduces the need for costly emergency repairs.

Timeline

  • December 2019: Project was advertised for competitive bidding.
  • January 2020: Project awarded to C.A. Carey Construction.
  • July 26, 2020: Construction began.
  • Fall 2020: Construction is scheduled to be complete.

Funding

Financial Data for PIN 109926Y
Funding Source Amount ($ in thousands)
2003 Gas Tax (Nickel Funding) $0
2005 Gas Tax (TPA) $0
Pre-Existing Funds (PEF) $1,257
CWA $0
Total $1,257

Contact

Tom Pearce
WSDOT Communications
206-440-4696
tom.pearce@wsdot.wa.gov

A small map showing the location of the SR 99 Duwamish River Bridge select grid deck replacement project.