Salesforce Park

The Transbay Terminal redevelopment was one of the largest architectural competitions of the 2000s: replace an aging transit hub in downtown San Francisco and give the city a signature tower. Pelli Clarke Pelli hired Except to jointly develop the conceptual design and the environmental concept. The argument Except made was simple and, at the time, unusual: a rooftop park could be a true ecological system rather than potted plants and a lonely olive tree. The team won in 2007.

The integrated concept treated the roof as living infrastructure. Natural ventilation pulls fine particulates from the underground air; the landscape above sequesters carbon and other pollution; rainwater is captured and filtered for use on site; and funiculars carry people from street level up to the park. Except's involvement spanned the main concept, the roof park, the ecological and water systems, the main square, and the bridge connections, with environmental engineering by Atelier Ten.

Work ran from 2007 to completion in 2019. In 2017 the project was renamed Salesforce Park, beside Salesforce Tower, under a long-term sponsorship agreement. The built 5.4-acre rooftop park, delivered by PWP Landscape Architecture, runs nearly four blocks above the transit center and now serves as the district's central public open space.

What makes it regenerative is that the design adds ecological value to one of the densest parts of the city: cleaner air, captured and recycled water, habitat for birds and pollinators, and a green space whose benefits reach beyond its own footprint. Except's contribution was the concept that made the ecological case and helped win the competition.