Contents tagged with viaduct

  • + How are you managing parking during construction?

    WSDOT and program partners meet regularly with a group of Pioneer Square and central waterfront stakeholders to identify and implement parking mitigation strategies. A plan to address short- and long-term parking concerns in these neighborhoods was completed in 2012. Example strategies include: partnerships with parking facilities to offer low-cost, short-term parking options; wayfinding signs that direct drivers to the parking supply; a responsive mobile website that provides data on parking availability and directions; and a public awareness program to let visitors and the general public know that parking is available in Pioneer Square and on the waterfront during SR 99 tunnel construction.


  • + Is viaduct replacement construction being coordinated with other nearby projects?

    WSDOT coordinates with partner agencies on nearly every aspect of the program including overall strategy and management, project schedules, construction and public involvement. Project coordination extends beyond the SR 99 viaduct replacement - coordination with the Seawall Project, the Seattle Multimodal Terminal at Colman Dock ProjectWaterfront Seattle and many other projects is vital to keeping traffic and construction moving.


  • + When will the viaduct be demolished?

    Crews will begin removing the Alaskan Way Viaduct after the new SR 99 tunnel opens to drivers. Tunnel opening is currently scheduled for early 2019. Removing the Alaskan Way Viaduct, which stretches along the waterfront from South King Street to Battery Street, is expected to take about six monthsIn 2011, crews demolished the southern mile of the viaduct, which accounted for nearly half the structure's total length. 


  • + What will happen to the Battery Street Tunnel?

    The Battery Street Tunnel was constructed in the 1950s and is at the end of its useful life. WSDOT’s final environmental document for the program included decommissioning (filling and sealing) the tunnel, and so WSDOT has a legal obligation to implement that plan.
    Community ideas have been proposed for alternative uses for the tunnel. However, given the age and condition of the structure, it would need significant and costly structural and system upgrades in order to be safe for other uses. WSDOT will be decommissioning the tunnel as part of a design-build contract that also includes demolishing the viaduct and connecting surface streets at the tunnel’s north portal.


  • + Is most of the traffic using the viaduct going to downtown or through downtown?

    WSDOT estimates there are more than 90,000 vehicles currently using the viaduct daily. Because this is an old road, there are no automatic traffic counts to pinpoint the number of vehicles that use the downtown ramps. A traffic count of three days in March 2018 (Tuesday – Thursday) showed that approximately 25,000 cars exited northbound at Seneca and Western Streets and approximately 31,000 cars entered the viaduct at Western Ave., Elliott Ave. and Columbia Street.


  • + Is the viaduct still a safe structure on which to drive?

    Routine safety inspections and maintenance keep the viaduct safe for public use. In 2008, crews strengthened four column footings where the viaduct had settled approximately five-and-a-half inches into the ground since the 2001 Nisqually earthquake. The column safety project limits settlement in this area of the viaduct and prevents further damage to the structure.

    We also installed a system designed to close the viaduct automatically in the event of a moderate to severe earthquake in the greater Seattle area. The automated closure system consists of traffic gates at all viaduct access points controlled by an earthquake detection system. If the earthquake monitoring system detects significant ground movement, it will simultaneously lower all nine traffic gates and safely close the viaduct in two minutes.

    In 2011, crews demolished nearly half of the vulnerable viaduct near Seattle’s port and stadiums. Drivers now use a construction bypass connected to new side-by-side bridges built to current safety standards.


  • + Why is replacing the viaduct important to public safety?

    The Alaskan Way Viaduct was built in the 1950s, and decades of daily wear and tear have taken their toll on the concrete structure. While it remains safe for everyday use, it also remains vulnerable to earthquakes.
    The 2001 Nisqually quake damaged the structure and hastened plans for its replacement. WSDOT has since repaired and strengthened the viaduct, and conducts twice-yearly inspections for safety. Parts of the viaduct, however, remain built atop fill soil that could liquefy in an earthquake. A tunnel will provide a much safer roadway for people travelling along SR 99. 
    Replacing the aging seawall is another element of improving the Seattle waterfront's resiliency against earthquakes. Visit the Waterfront Seattle website for information on the seawall replacement project.


  • 1