Project Title & Location

SR 99 - Alaskan Way Viaduct and Seawall Replacement Program

Project Description
The existing seismically vulnerable Alaskan Way Viaduct and Seawall are both at the end of their useful life and at risk of sudden and catastrophic failure in an earthquake. The cost to replace in-kind this seismically vulnerable structure is between $2.0 and $2.4 billion. (This figure does not include the cost of replacing the seawall or work north of Battery Street tunnel. Necessary to protect public safety and maintain the transportation corridor.

Contractor/Consultant
PB Americas is the prime design consultant. Hatch Mott MacDonald is the Program Management Assistant Consultant

Recent Progress
Construction began on Stage 1 of Electrical Line Relocation to remove electrical power lines from the southern section of Viaduct in anticipation of demolition of that area in 2012.  Design work continues on the Battery Street Tunnel Fire and Safety Improvements Project with Advertisement forecasted to begin mid-2009. Work continues to support the Stakeholder Advisory Committee and the Executives from WSDOT, City of Seattle and King County for Central Waterfront Viaduct replacement scenarios.

Design Construction Impacts
Design is 90% complete for the Phase One Contract on the Viaduct Removal Holgate-to-King Project and  approaching 90% complete for the Stage 1 Battery Street Tunnel Fire Life Safety Improvements Project.  Design continues to progress for other program elements.  Major Roadway construction is planned to begin Winter 2009.

Environmental Impacts / Compliance
Program Environmental staff continues to work on the environmental document for the Holgate to King Viaduct Replacement Project and other Moving Forward Projects.  Forecast FONSI approval for Holgate to King Viaduct Removal in December 2008

Impacts to Traffic
Utilities construction, currently scheduled to begin in September 2008, will impact traffic on local city streets in the Stadium district.  Night and weekend lane closures through the Battery Street Tunnel are likely to begin mid-2009.  Traffic impact mitigation is underway with agreements under negotiation with the City of Seattle and King County for Traffic Enhancements and Local Improvements as well as design for I-5 Advanced Traffic Management.

Planned vs. Actual Expenditures
(Total Project Cost)

Nickel funds included in above costs

2005 Transportation Partnership Account