The existing 2.2 mile double-decker viaduct has allowed millions of drivers to reach their destinations through the north-south corridor that runs along downtown's waterfront. Originally built in the 1950's, the roadway was designed to carry 65,000 vehicles per day. Today, about 110,000 cars travel the viaduct daily. The 2001 Nisqually Earthquake - 6.8 on the Richter scale - confirmed what many transportation leaders had feared: the viaduct was in need of repair and could pose a safety threat. It was also determined that the sea wall, which helps support the viaduct, would also need to be replaced due to age, deterioration, seismic vulnerability and risk to public safety.
The Alaskan Way Viaduct is just a portion of State Route 99 that the Washington State Department of Transportation (WSDOT) is beginning to improve. WSDOT has teamed up with the Federal Highways Administration (FHWA) for the highway reconstruction and the city of Seattle has joined in to help on the portion of the Alaskan Way Viaduct which runs along the waterfront. Together, the three agencies studied nearly 80 replacement options.
By 2006, two of the replacement options emerged as favored front runners: an elevated structure rebuild or a cut-and-cover tunnel.
Several City leaders favored the cut-and-cover tunnel and viewed the option as the opportunity to reclaim Seattle's waterfront. Several state and city transportation officials also preferred the tunnel option, but not all embraced the plan. Many prominent state lawmakers claimed the project was too costly and that funding for the proposed six-lane double-decker cut and cover tunnel wasn't completely clear.
In mid-December 2006, Governor Christine Gregoire stated the controversial decision was at a stalemate and called for an advisory ballot from Seattle residents. She wanted to see a ballot that consisted of both the tunnel and rebuild option, complete with their cost estimates.
Responding to concerns over costs, City leaders created a smaller, four-lane Surface-Tunnel proposal - essentially scraping the six-lane double-decker design. The new proposal consists of tunnel lanes side-by-side and shoulder lanes that would turn into extra lanes during peak travel times. State leaders claimed it was a last minute attempt for the City to keep the tunnel option alive and that there wasn't adequate time to study the option. But that didn't deter Seattle Council Members who voted January 19, 2007 to put the new Surface-Tunnel Alternative and Elevated Structure Alternative on a special March 13, 2007 ballot.
However that wasn't enough to convince Seattle voters they needed a tunnel to replace the Viaduct.
In the nearly 100,000 ballots counted March 13, 2007, Seattle voters overwhelmingly rejected both the proposed viaduct rebuild and the tunnel options.
Following the March 2007 vote, Governor Christine Gregoire, King County Executive Ron Sims and Former Seattle Mayor Greg Nickels agreed to move forward on the non-controversial improvements to the north and south ends of the corridor; these projects will replace about half of the seismically vulnerable structure.
In addition, the executives also directed their three transportation departments to solve what The Seattle Times called the "riddle in the middle," the one-mile section of the viaduct that runs along Seattle's central waterfront.
In January 2009, the Governor, County Executive and Mayor recommended replacing the central waterfront section of the viaduct with a bored tunnel beneath downtown, a new waterfront surface street, transit investments, and downtown waterfront and city street improvements. You can watch a 90-second simulation of the bored tunnel.
As The Seattle Times reported the three executives also outlined a budget and many specific projects included in the plan.
Governor Gregoire proposed that the state government spend $2.8 billion from state gas taxes and federal highway funds on a two-mile bored tunnel under Seattle's streets.
Former Mayor Greg Nickels outlined his plan to spend $930 million to make a variety of transportation improvements to make the viaduct replacement plan work well. The Mayor's list included: replacing parts of the Alaskan Way Seawall, building a new streetcar line on First Avenue, and changes to the Mercer and Valley Streets in South Lake Union.
King County Executive Ron Sims proposed that Metro transit increase its bus service to help mobility in the viaduct corridor by seeking authority from the Washington State Legislature to levy a one-percent car-tabs tax for transit on motor vehicles in the county.
- City Of Seattle
The City owns the seawall and the Alaskan Way surface street. The City is responsible for most of the utilities in the corridor.
- Washington State Department of Transportation (WSDOT)
WSDOT is responsible for the Viaduct and State Route 99.
- Federal Highway Administration (FHWA)
FHWA provides roadway design guidance and environmental oversight.
- Allied Arts
In the spirit of the "Save the Pike Place Market" campaign, Allied Arts is working to replace the Alaskan Way Viaduct with Seattle's next great civic space.
- People's Waterfront Coalition
Organization who want to prevent the construction of a new highway on the shore of Elliott Bay in Downtown Seattle.
- No Tunnel Alliance
Coalition of people who are opposed to replacing the Alaskan Way Viaduct with a tunnel.
According to the Washington State Department of Transportation (WSDOT) the total cost of all the improvements included in the bored tunnel alternative is $4.24 billion. In addition to a bored tunnel, the alternative includes removing the elevated viaduct along the central waterfront, constructing a waterfront promenade, and implementing other transit and surface street improvements. The state has committed $2.8 billion to this program, of which $2.4 billion has been approved by the legislature as part of the 2003 and 2005 transportation investment programs. $400 million would come from tolling the tunnel. The Port of Seattle, King County, and the City of Seattle will fund the remaining $1.44 billion through local sources.
WSDOT's latest timeline for the project is:
- 2009: Relocate electrical lines from the south end of the viaduct
- 2008 - 2013: Transit enhancements and other improvements to keep people and goods moving during construction of the S. Holgate Street to S. King Street project
- 2009 - 2013: Build new SR 99 between S. Holgate Street and S. King Street
- 2011: Begin construction on the SR 99 bored tunnel