Where cars once ruled: Seattle’s highway reborn as a public waterfront

After fifteen years between planning and construction, Seattle has opened to the public the new Waterfront Park, a 20-acre landscape and urban intervention that redefines the relationship between the city and Elliott Bay. The project, led by Field Operations, transforms the area once occupied by the Alaskan Way elevated viaduct into a continuous system of public spaces: pedestrian walks, bike paths, gardens, urban beaches, pedestrian bridges, and new event piers.

The park spans 26 blocks, connecting Pioneer Square to Belltown and restoring continuity between downtown, Pike Place Market and the water line. A pivotal element of the project is the Overlook Walk, an elevated walkway that reconnects the historic market to the Aquarium and commercial piers, offering panoramic views of the bay and skyline. The landscape design interprets the waterfront's industrial memory and places it alongside a natural lexicon inspired by the waters of Puget Sound. The ensemble includes large-scale civic spaces, play areas, gardens, landings, and stretches of urban beach, as well as art installations and artifacts that enrich the experience. Sustainability strategies integrate stormwater management, green infrastructure, and building details designed to last.

With a public and private investment of more than $800 million, the Waterfront Park was developed with input from Jacobs Engineering, WSP, HNTB, community groups and representatives of Native tribes. The transformation required an extensive infrastructure program: the construction of the new State Route 99 tunnel, the demolition of the old viaduct, the reconstruction of the Alaskan Way and Elliott Way waterfront, and the construction of new pedestrian bridges, including the Union Street Bridge and the Marion Street Bridge.