Seattle's Alaskan Way Viaduct

The Alaskan Way Viaduct started as a rail yard to accommodate the City's industrial needs along the waterfront of Elliot Bay in the 1880s. As the need for rail decreased with the rise of personal automobiles, the City built the viaduct in place of the rails in 1953, renamed State Route 99 and became the major north-south thoroughfare in Seattle. Today, traffic on the Viaduct is down for their roughly 100,000 daily vehicle peak (20-25% of downtown traffic), though recent rates are difficult to track. Studies conducted in the 1990s revealed the structure was reaching the end of its lifespan. Daily wear and tear, increasing age, salty marine air, and damage by the powerful Nisqually Earthquake in 2001 confirmed the weakening nature of the bridge, requiring costly emergency repairs and calling into question its long-term viability. The City of Seattle and the State of Washington agreed the viaduct must come down.

Viaduct Removal

In 2007, after a study by the University of Washington found that damage from continued post-earthquake settling will further harm the structure, they recommended the viaduct be destroyed within 4 years. In January 2008, Governor Christine Gregoire announced that "no action" was not an option and by 2012 the viaduct would come down. At the time of this statement however, no decision was made for a specific replacement.

Initial Proposals

The City of Seattle, the State of Washington and the Federal Highway Administration agreed the cut-and-cover tunnel was the prime replacement option for the viaduct. In the event the tunnel exceeded cost estimates, an alternative to rebuild the elevated viaduct was provided as well, each with price tags of $4 billion or more. Washington State and the City of Seattle grew increasingly embittered with one another disagreeing over which replacement to use, calling for a referendum among voters to decide the best option. In March 2007, the people of Seattle strongly voted against both options, welcoming in a surface transit option.

With the two expensive options off the table, Cary Moon and the People's Waterfront Coalition capitalized on momentum for a surface boulevard alternative. The organization envisioned an open, landscaped boulevard with built in options for transit. This human-scale structure would have re-opened the waterfront to the community and restore the shoreline, supporting a vibrant urban atmosphere. Further development along the newly opened 335 acres of public land on Seattle's waterfront could have given way to new parks, beaches, and development that could have ultimately save the city years of construction delays and billions of dollars. "If you try to build your way out of congestion," said Moon, "you'll ruin your city or go broke trying."

Future Plans

Despite best efforts to promote the surface boulevard option and criticism from local stakeholders, the City of Seattle, along with the county and state, replaced the cut-and-cover tunnel with a deep-bore underground tunnel option to reduce costs and traffic congestion. However, the $3.1 billion project is currently at a standstill after the drilling machine hit a well and broke down in December 2013. The machine broke just 1,023 feet into a 9,270-foot journey. A repair timetable estimates digging to resume in March 2015. Delays are not the only setback of the breakdown.

WSDOT and contractor Seattle Tunneling Partners are currently debating who should cover the repair costs estimated to add $125 million to the project budget. These repair costs include a large pit and concrete pad to fix the machine, though construction of the pit itself has stalled as local group Democracy Workshop filed suit in federal court in March 2014 naming WSDOT, the City of Seattle and the Federal Highway Administration as defendants. Democracy Now claims the pit is a “project within a project” that should not move forward without a further environmental impact study. Washington State Secretary of Transportation said she could not say 100 percent that the tunnel project will be finished as there is a possibility, albeit small, that the machine is unable to be repaired. Furthermore, if drilling does resume March 2015, the project still has over 8,000 feet to complete, leaving plenty of opportunity for further breakdowns, delays and additional costs.

Additional Information

People's Waterfront Coalition

Washington State Deparment of Transportation Alaskan Way Viaduct Program Information Center

Federal Highway Administration Alaskan Way Viaduct Replacement Program Executive Summary

Seattle Department of Planning and Development Central Waterfront Homepage

Get Involve

The Alaskan Way Viaduct, as seen from Elliot Bay, source: Wikipedia

One of three proposed surface level alternatives, image credit: Shawn McClung, flickr

Tunnel route, source: WSDOT