The Alaskan Way Viaduct Replacement Program is led by the Washington State Department of Transportation in partnership with the Federal Highway Administration, King County, the City of Seattle and the Port of Seattle. Each jurisdiction is responsible for its own projects’ management, environmental work, design and construction.
The state is responsible for leading or funding 30 of the projects that will work together to reshape the SR 99 corridor. Construction on our first project started in 2007, when crews stabilized four viaduct columns that settled following the 2001 Nisqually Earthquake. Since then, 24 projects that are led or funded by the state have been completed, with several more in progress or set to break ground soon.
- Bored Tunnel: This contract with Seattle Tunnel Partners includes the bored section of the new SR 99 tunnel, the tunnel’s interior structures, and the operations buildings at each portal. Work began in 2011.
- North Access: Completed in 2017 by Atkinson Construction, this contract connected the SR 99 tunnel’s north entrance to SR 99 north of the Mercer Street bridge; built new on- and off-ramps at Republican and Harrison streets; extended Sixth Avenue North between Harrison and Mercer streets; and improved water and sewer lines in the area.
- South Dearborn Street Off-Ramp Bridge: Completed in 2017 by Interwest Construction, this contract built the earthquake-resistant northbound SR 99 off-ramp to South Dearborn Street, which will open when the SR 99 tunnel opens to traffic.
- SR 99 Connections: Scheduled to begin in 2018, this contract will make the final connections between the tunnel’s portals and SR 99, necessary to open the tunnel to traffic.
- South Access: Surface Street Connections: Scheduled to begin in 2019, this contract will complete surface street improvements near the tunnel’s south portal.
- SR 99 Viaduct Demolition, Decommissioning and Surface Street Project: Scheduled to begin in early 2019, this contract will demolish the viaduct, decommission the Battery Street Tunnel, and reconnect Aurora Avenue North intersections near the tunnel’s north portal.
- Waterfront Seattle Construction: To be built by the City of Seattle’s Office of the Waterfront beginning in 2019, this project will build the new Alaskan Way street along the waterfront after the viaduct is demolished.
Seattle Tunnel Partners' schedule
Our contractor, Seattle Tunnel Partners, is responsible for designing and building the SR 99 tunnel. Our contract with STP includes a number of elements. In addition to boring the tunnel and building the highway within it, STP is responsible for building highway ramps and other connections at the north and south ends of the tunnel. They are also constructing buildings at each tunnel portal to house lighting, ventilation and other systems needed to operate the tunnel.
Summary versions of STP's previous monthly schedules are posted below. In spring 2016 WSDOT did not post STP schedules while STP was updating its baseline schedule based on recent tunneling progress.
- July 2017 schedule (pdf 125 kb)
- June 2017 schedule (pdf 195 kb)
- May 2017 schedule (pdf 208 kb)
- April 2017 schedule (pdf 249 kb)
- March 2017 schedule (pdf 265 kb)
- February 2017 schedule (pdf 233 kb)
- January 2017 schedule (pdf 262 kb)
- December 2016 schedule (pdf 238 kb)
- November 2016 schedule (pdf 224 kb)
- October 2016 schedule (pdf 243 kb)
- September 2016 schedule (pdf 222 kb)
- August 2016 schedule (pdf 215 kb)
- July 2016 schedule (pdf 194 kb)
- June 2016 schedule (pdf 196 kb)
- May 2016 schedule (pdf 557 kb)
- February 2016 schedule (pdf 221 kb)
- January 2016 schedule (pdf 280 kb)
- December 2015 schedule (pdf 226 kb)
- November 2015 schedule (pdf 258 kb)
- October 2015 schedule (pdf 316)
- September 2015 schedule (pdf 291 kb)
- August 2015 schedule (pdf 324 kb)
- July 2015 schedule (pdf 481 kb)
- June 2015 schedule (pdf 238kb)
- May 2015 schedule (pdf 568 kb)
- April 2015 schedule (pdf 112 kb)
- March 2015 schedule (pdf 107 kb)
- February 2015 schedule (pdf 569 kb)
- January 2015 schedule (pdf 155 kb)
- December 2014 schedule (pdf 132 kb)
- November 2014 schedule (pdf 143 kb)
- October 2014 schedule (pdf 148 kb)
- September 2014 schedule (pdf 138 kb)