An alternative route to urban renewal
The Alaskan Way Viaduct is an elevated, double-decked section of State Route 99 that runs across the Elliott Bay waterfront in the industrial district and downtown of Seattle. Since its construction in the 1950s, the viaduct has encountered numerous structural and serious seismic issues, and is now in need of replacement.
A multitude of differing plans have been proposed, including a scheme to turn the structure into a unique public park providing stunning views across the city.
BuroHappold Engineering led the team that studied the feasibility of reimagining part the viaduct into five acres of waterside green space. Working alongside the architect, construction consultants and the client, we reviewed the structural issues conceptually and mapped out the possible costs involved in the project. A key challenge for our team was to illustrate the benefits that retaining the structure would bring for the city and the community.
Plans to remove the viaduct completely and replace it with a waterside park were already established, so it was our role to demonstrate alternative options. Our proposed designs showed that creating an elevated park would not only offer a unique public realm for the city but also provide a highly sustainable solution by reusing an existing structure.
The results of the study led by our engineers recommended persevering 14 blocks of the upper deck of the viaduct, while also constructing a new pedestrian bridge to connect the park to other key access points. Our work ensured that the client had a comprehensive feasibility report, detailed options and associated costs and the preferred way forward to put together the case for developing the park and retaining Alaskan Way Viaduct.
Now entitled Initiative123, the project to preserve a part of Seattle’s history and provide a unique facility for the city’s community is set to be considered for approval in summer 2016.
Services and approach
When we integrate our specialist teams around an approach, the benefits to the client multiply