WSDOT seeks design-build team for tunnel project

SEATTLE — The Washington Department of Transportation (WSDOT) issued a request for qualifications to contractors interested in building the proposed SR 99 bored tunnel to replace the Alaskan Way Viaduct — the first step in the process to select a design-build contractor to deliver the tunnel project.

“This project is another step toward replacing the aging and vulnerable Viaduct,” said Paula Hammond, Washington Transportation Secretary. “Agreement with the city of Seattle and King County to build the SR 99 bored tunnel means we can begin the process of selecting a contracting team for what will be the largest viaduct replacement contract. We’re expecting some of the top engineering and construction teams to express interest in this world class project.”

The RFQ asks teams to submit a statement of qualifications by Nov. 16, 2009, which WSDOT will evaluate and score. The agency plans to announce in January a short-list of three to four most qualified design-build teams to submit proposals. The successful team will be selected at the end of 2010.

Those proposals will detail the firms’ plans for constructing a tunnel boring machine, the final design and construction of a new bored tunnel beneath downtown Seattle beginning in 2011, and the interior roadway, tunnel systems, ventilation buildings and connections to the portals. The contract is estimated at approximately $1 billion. Additional contracts for tunnel portals and other work are forthcoming, and will bring the total cost of the bored tunnel to $1.9 billion.

Early this year, the state, county, city, and Port of Seattle agreed to replace the Alaskan Way Viaduct with a deep bored tunnel. The plan includes a new waterfront boulevard and public open spaces, transit investments, a new central waterfront seawall, and other city street improvements. The total cost of the Alaskan Way Viaduct and Seawall Replacement Program is estimated at $4.24 billion.

The 2009 Legislature directed WSDOT to move forward with the bored tunnel and has $2.4 billion in committed state dollars to the project. An estimated $400 million will come through tolls on the new SR 99 tunnel. The agency is focused on delivering the tunnel on an aggressive schedule, given the vulnerability of the existing Viaduct. Crews are currently gathering soil samples along the alignment for the proposed tunnel to aid in the design of the tunnel boring machine and the tunnel itself. Environmental review is underway, and a supplemental draft environmental impact statement will be available for public comment in early 2010.

While preliminary design of the tunnel progresses, the state is moving forward to replace almost half of the Viaduct with a new roadway south of downtown near the sports stadiums. Road and bridge construction on this new mile of SR 99 will begin early next year.

For more information on the Alaskan Way Viaduct replacement program, visit www.alaskanwayviaduct.org.