With sea levels rising and catastrophic storms and flooding becoming more frequent and severe, waterfront cities need to reinvent themselves to protect land, buildings, infrastructure, and people. At the 2015 Fall Meeting in San Francisco, panelists discussed projects that tackle these challenges in ways that enhance public safety and also create value.
Cathy Simon, design principal with Perkins + Will, mentioned several promising models for green infrastructure at the water’s edge, including Brooklyn Bridge Park. “It’s an amazing park, but it’s also resilient,” she said. “It uses topography and an almost didactic design concept.” Salvaged pieces of granite form an amphitheater stepping up a hillside, providing protection from sea-level rise and storm surges on the East River. “It is resilient, but it’s also an amphitheater, which is about the pleasure of being in a place like this—of looking and being with other people, of engagement.”
Simon also pointed to restoration and rehabilitation of Crissy Field, a former military installation at the northern edge of San Francisco, which creates a tidal lagoon and a barrier beach that the public can enjoy. In Germany, HafenCity, the redevelopment of an area along the Elba River, is constructed 26 feet (8 m) above the flood level to protect it from flooding. “It’s built for resiliency and housing and all kinds of things that really bring people to the water,” Simon said.
Will Travis, sea-level rise planning consultant and former executive director of the San Francisco Bay Conservation and Development Commission (BCDC), noted that over the past century, the level of San Francisco Bay has already risen about eight inches (20 cm). San Francisco and Oakland’s airports, as well as Silicon Valley, are all in danger of falling below sea level.
“Silicon Valley faces a double jeopardy,” Travis said. It previously was home to fruit orchards irrigated with well water, causing the ground elevation to sink so significantly that much of the South Bay shoreline is below current sea levels. The shoreline is separated from the bay by a mosaic of salt ponds, but the levees between the salt ponds weren’t designed for flood protection. “They are essentially heaps of dirt,” Travis said. “Silicon Valley could be flooded if an earthquake melts those heaps of dirt into pools of mud.”
The BCDC has crafted regulatory requirements for addressing rising sea levels. In 2011, BCDC became the first state coastal management agency in the nation to require that sea-level rise be addressed in the plans for new shoreline development. The first large project BCDC approved was the Brooklyn Basin redevelopment in Oakland.
Amy Chester is managing director of the Rebuild by Design competition, which the U.S. Department of Housing and Urban Development (HUD), the Rockefeller Foundation, and other philanthropic organizations created in the wake of Hurricane Sandy. She noted the high economic cost of Sandy, totaling $65 billion worth of damage, with 650,000 homes damaged or destroyed. “The storm unveiled interdependent vulnerabilities across the region,” she said. “We realized that what we need to do is have some time to think before we start building back exactly what was there before, or just building things a little higher.”
The competition sought to address this by inviting multidisciplinary design teams to develop solutions after engaging in research and making site visits throughout the region affected by Sandy to meet with government officials, residents of public housing, emergency responders, and others. Of the ten teams selected, HUD chose to implement proposals by six of them in New York and New Jersey. Rebuild by Design is now working with other cities, including Boston, San Francisco, and Chicago, to replicate the process.
David Waggonner III, president of Waggonner and Ball Architects, noted that Dutch experience with water issues has been invaluable in efforts to protect New Orleans. After Hurricane Katrina struck, the Dutch embassy in Washington, D.C., the American Planning Association, and Waggonner and Ball collaborated to study how to rebuild the city’s resilience. This resulted in the creation of the Greater New Orleans Water Plan.
Heavy rainfall regularly overwhelms New Orleans’s drainage system. However, the city’s historic methods of immediately draining stormwater have left the soil so dry that the ground has sunk below sea level. The Greater New Orleans Water Plan follows the Dutch approach, which involves retaining water and storing it before draining it. The plan aims to delay stormwater release through rain gardens, bioswales, retrofitted and new canals, and new ponds, using stormwater to enhance neighborhoods.
Most of New Orleans’s existing waterways are hidden or inaccessible, providing little value to the public—an approach that makes it harder to increase the willingness of people to spend tax dollars on water infrastructure. “If you divorce investment from what people want or what people think is beautiful, you probably won’t get them to pay for it,” Waggonner said. “The more it connects to their culture and history, the easier it is for them.”