Building section [illustration courtesy of Transbay]
Transbay interior [rendering courtesy of Transbay]
After eight years of construction and many more of planning, San Francisco’s much-anticipated Transbay Transit Center—officially called the Salesforce Transit Center, after the cloud-computing giant acquired naming rights for $110 million—opened this summer.
The four-block-long terminal, dubbed “the Grand Central of the West,” connects eight Bay Area counties and beyond through 11 transit agencies, including BART; Muni; AC Transit, which serves the East Bay; CalTrain, which runs through Silicon Valley to San José; and—eventually, perhaps—the $100 billion California high-speed rail line linking San Francisco and Los Angeles.
The $2.7 billion transit hub is packed with innovative and sustainable design features that will enable the facility to achieve LEED Gold certification. They include a gently undulating, perforated exterior wall that screens buses from view, provides natural ventilation, and creates a dramatic Grand Hall with a soaring “light column” that washes the interior in natural light. But perhaps the most innovative element of the design is a 5.4-acre rooftop public park that provides much-needed open space for transit passengers, neighborhood residents, and workers in nearby office buildings.
In a recent interview with CREW SF, lead architect Fred Clarke said that one of the driving forces behind the design of the new transit center was to create a facility that was easily accessible and well integrated into the fabric of the neighborhood, the rapidly developing SoMa district, just south of the city’s Financial District.
“Large transportation centers generally have a negative impact on the neighborhood,” Clarke observed. “Penn Station in New York is a good example. They tend to be very unfriendly as they reach the ground. The movement of vehicles in and out creates pollution, waste, and congestion… We wanted the [Salesforce] building to be very welcoming and friendly and permeable. We wanted it to support the growth of the neighborhood.”
To reduce ground-level congestion and pollution, most of the buses entering and leaving the building have been “lifted off the ground” via a bridge that links directly to the Bay Bridge. Indeed, the design of the bridge is actually a scaled-down version of the new eastern span of the Bay Bridge, with its distinctive single-tower design.
The transit center has been carefully aligned with the existing street grid so that pedestrians can easily walk through the building. And it is filled with welcoming art designed to draw the public in, such as the colorful terrazzo floor in the Grand Hall, designed by local artist Julie Chang, which evokes a lush, sunlit Victorian garden.
But the most welcoming element of the new center is unquestionably the rooftop park, which Clarke believes was a pivotal element in persuading the judges to pick the design of his firm (Pelli Clarke Pelli, based in New Haven, CT) over several other proposals. “It’s unique and unprecedented,” Clarke remarked, noting that the only park that can compare to it is the High Line in New York, a 1.5-mile-long elevated greenway fashioned out of an abandoned rail spur.
“The park was our invention. It wasn’t in the original requirements,” Clarke said. “Everybody loved the idea.”
The quarter-mile long elevated park features an impressive array of amenities, including an outdoor theater, gardens populated by dozens of mature trees, a half-mile-long walking loop, open grass areas, and a children’s play space, as well as a restaurant and café. The park design includes active spaces that allow for organized events like concerts and fairs, along with quiet areas where visitors can relax in informal natural settings.
One of the most innovative features of the elevated park is a water sculpture, designed by Bay Area artist Ned Kahn, composed of a thousand-foot-long line of water jets triggered by sensors in the bus deck below. The frequency, motion, and height of the jets corresponds to the level of activity below, making the arrival and departure of buses tangible to people in the park.
Clarke said his team approached the roof of the transit center as a “fifth façade,” because many of the neighboring high-rises would look down on it. If office workers in nearby buildings could view a beautiful park rather than a sea of asphalt, they reasoned, that would be a big asset for the neighborhood.
The park also doubles as a “living roof,” providing shade to ground-level sidewalks, habitat for flora and fauna, and insulation for interior spaces, moderating heat buildup in warm weather and retaining heat during cooler weather. And unlike conventional roofs, which tend to absorb heat, the park cools the surrounding environment and improves air quality by capturing and filtering exhaust fumes.
One of the biggest challenges in building a park several stories above the ground was how to make it accessible to the public. To address that challenge the designers provided multiple means of access, including an express elevator, escalators, stairs, pedestrian bridges linking to the 61-story Salesforce Tower and an adjacent high-rise, and a diagonal elevator, or funicular, that rises through a copse of redwood trees from the main entry plaza at the corner of Mission and Fremont Streets.
The inspiration for the intricately designed, perforated metal apron that wraps around the building came from Roger Penrose, a renowned British mathematical physicist who has been exploring nonrepeating patterns for decades. Clarke was familiar with Penrose’s work because he had been a physics major himself in college before turning to architecture.
“It’s a simple idea but very complex,” Clarks says of Penrose’s design. “You can stare at it forever,” because it never repeats itself. “It’s like a flower that keeps opening and blossoming. It’s the perfect intersection of science, architecture, and art—which is a perfect metaphor for the Bay Area.”
The transit center was built on top of a giant underground concrete box designed to be the terminus for CalTrain—via a 1.3-mile-long tunnel from the current CalTrain station at the corner of 4th and King Streets—and the high-speed rail line. But adding those rail components will take many more years and hundreds of millions of dollars—and it’s far from clear whether the political will or the financing exist to make it happen.
About the Author
Jen Chan, MBA, is the CEO and founder of White Tiger Condo Conversion. Headquartered in San Francisco, White Tiger innovates alternative real estate ownership and wealth strategies by leveraging leading-edge digital technology. Jen’s mission is to revolutionize the American Dream through condo conversion—making property ownership and equity available to more people while at the same time building vibrant communities. She has more than 25 years of experience in residential and commercial real estate and related fields. For additional information, visit WhiteTiger.us.
Unfortunately, the Salesforce Transit Center has been temporarily closed since the original writing of this article. A fissure was found in a steel support beam leading the Transbay Joint Powers Authority to authorize a temporary closure of the center while the situation is under investigation.