Nearly 20 Years of Planning Comes to Fruition: SR 99 Tunnel Opens to Traffic


This week, the State Route 99 tunnel through downtown Seattle opened to traffic, culminating many years of planning efforts. At over $3 billion, the Alaskan Way Viaduct Replacement Program has been one of the largest transportation investments in Washington State. The now-closed viaduct carried more than 110,000 vehicles per day along the City’s waterfront. While many Seattleites will miss the view from the double-decker freeway, we will all be much safer. The structure was not expected to withstand the “big one” – the major earthquake due for the Seattle area. The possibility of damage or failure in the next earthquake gave the project a sense of urgency and drive for progress.

View from the Alaskan Way Viaduct

Parametrix began working on the environmental impact statement (EIS) for the project to replace the Alaskan Way Viaduct and Seawall in September 2001. The draft impact statement was completed in nine months, won several local and national awards for its readability and design, and set a new standard for how environmental documents are being written. The Washington State Department of Transportation (WSDOT) and Parametrix pioneered new ground by creating a reader-friendly environmental document based on four concepts—tell a story, make it visual, engage the reader, and make it brief. Parametrix continued to lead the environmental review all the way to the Record of Decision and prepared updates as needed during construction.

The environmental documentation isn’t the only part of this project where Parametrix offered innovative solutions. Parametrix was a part of a multi-consultant team responsible for evaluating alternatives and designing a replacement facility. Employee-owner Kirk Wilcox “developed and presented a cost savings alternative for the North Portal that saved at least $30 million” according to Susan Everett, project manager with WSDOT.

On Friday evening, the team who has worked so hard on this project got a sneak peak of the tunnel from the North Portal. WSDOT invited consultants and contractors to the event to celebrate the work the team had done over the years.

Jill Czarnecki (Parametrix), Kathy Rossi (Retired), Maya Hunnewell (Seattle Department of Transportation)

Everyone had the opportunity to join in on the fun over the weekend at grand opening events for the tunnel including a fun run, bike ride, and tunnel walk. Many Parametrix employee-owners got in on the fun, including Alyssa Worsham and Kaylee Moser pictured below at the Viaduct to Tunnel 8K run.

The project isn’t quite complete just yet though – the work along the waterfront continues. With the viaduct gone, the City is capitalizing on the opportunity to transform the waterfront. Parametrix is providing multimodal transportation analysis, planning, and environmental documentation for the Waterfront Seattle Program. The project spans the waterfront from Pioneer Square to Belltown. It includes the rebuilt Elliott Bay Seawall, twenty acres of new and improved public space, improved connections between center city neighborhoods and Elliott Bay, critical utility infrastructure, and new Alaskan Way and Elliott Way surface streets to serve all modes of travel.

Parametrix is honored to have a role in this iconic Seattle project and we are thrilled to see the vision come to life.

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