Replacing the Alaskan Way Viaduct: We’re ready. Are you?

For many years, the main questions surrounding the Alaskan Way Viaduct replacement were – what will be built and when will construction start? We began answering these questions earlier this summer, as crews broke ground on a project to replace the southern mile of the aging structure with a new side-by-side roadway. Now that construction has begun, the question becomes – how will people get around during this work? Luckily for those who depend on the viaduct and State Route 99 today, we’ve been planning this work for a long time. And the pieces to help keep things moving are falling into place.

In February 2008, we, along with the King County and the City of Seattle announced a package of transit service and capital investments to minimize travel delays and disruptions during construction to replace the viaduct’s south end. Our contribution totaled approximately $125 million. During the last two and a half years, we worked with our partners to add these improvements and bolster a system that already includes new Link light rail, upcoming RapidRide bus routes, West Seattle ferry service and repaved downtown streets.

We are doing everything we can to keep lanes open on SR 99 during the viaduct replacement. Through the south end construction area, at least two lanes will remain open in each direction at most times, but reduced speeds in this area mean people will need options for getting around. So, what improvements did we put in place, and how will they help you? Let’s look at the list:

SR 519 Project
  • This spring we completed the SR 519 project, which included a new I-5/I-90 westbound off-ramp to S. Atlantic Street/ Edgar Martinez Drive S. Drivers now have a new connection that provides better access from I-5 and I-90 to the waterfront.
  • Earlier this year, King County Metro, with funding from us, added 31 new bus trips on four routes to and from southwest Seattle. Strategies to encourage the use of transit, teleworking and ridesharing will kick into high gear next year. To see how transit can help your commute to downtown, check out Metro’s Trip Planner.
  • We also provided funding so Metro could expand its bus monitoring system. Completed this summer, the expanded system will help Metro monitor when travel times along transit routes are affected by construction, so they know when and where additional service is needed to help you reach your destination.
  • This month we activated new overhead electronic signs on northbound I-5 between Boeing Access Road and I-90 that alert drivers to reduce speeds or change lanes when there are backups on the road ahead. We’ve also added new travel time signs on I-5. These tools provide real-time information to help drivers make their commute more manageable. 
  • The City of Seattle has opened its new Spokane Street Viaduct off-ramp to Fourth Avenue S. The eastbound off-ramp provides a new route into downtown for West Seattle commuters. Our contribution of $50 million completed full funding of the City’s $168 million Spokane Street project, allowing it to move into construction.
  • We funded City projects to add and upgrade traffic signals and add new driver information signs in the Elliott Avenue/15th Avenue NW, West Seattle and south of downtown corridors. These improvements will help keep buses and traffic moving.
  • Smart Highway signs
  • Later this year crews will finish installing and testing new electronic message signs on SR 99 and other major routes leading to downtown. The signs will provide real-time information to drivers so they can choose less congested routes.
With improvements in place, our focus now is giving you the information you need to reach your destination, whether by hopping on a bus or choosing a different route. Getting around during construction provides resources for checking current traffic conditions, current construction lane closures, bike route changes, and much more. We also created an interactive simulation that lets you see different views of the construction stages for the south end replacement. This is a good way to see roughly when SR 99 and city streets near Seattle’s stadiums will be affected by construction.

And if you have questions, we’re just an e-mail or a phone call away. You can reach us at and 1-888-AWV-LINE (298-5463).