Washington State Department of Transportation—Alaskan Way Viaduct Demolition

For almost 70 years, the Alaskan Way Viaduct greeted travelers as they made their way down State Route 99 in Seattle. Originally a critical connector for freight traffic, the design of the road was outdated and posed a safety concern, as it was not suited to withstand an impeding earthquake. Working with Seattle, King County, and the Federal Highway Administration, the Washington State Department of Transportation (WSDOT) spent nearly 20 years coordinating this $93.7 demolition effort. This project did not come without challenges, as the viaduct sat close to close to buildings, traffic and pedestrians. WSDOT had to execute the demolition in the safest way possible. After nine months of work, WSDOT was finally able to remove 1.4 miles of roadway, along with 122,000 tons of concrete, 400 columns, and 7,000 tons of steel. Now, Seattle’s new waterfront is beginning to take shape, with 20 acres of public space, connections to bike and walking paths, and more – improving the quality of life in the city for years to come.