This is the second of several articles examining how the building industry and building owners are addressing future effects of climate change. Click here for the first article, which examined responses to sea-level rise in Boston.
Hurricane Sandy brought new urgency to New York City’s ability to recover from severe storm surge. And with sea levels projected to rise 11 to 24 inches by 2050, Mayor Michael Bloomberg recently unveiled a $20 billion plan to help the city brace for the realities of climate change. Architects, designers, and urban planners should also consider how they will address rising sea levels and increased storm surges as they design new buildings and retrofit existing ones.
Two designers are actively engaged in the city’s resiliency efforts: Robin Guenther, FAIA, sustainable healthcare design leader in Perkins+Will's New York office, and Claire Weisz, principal at New York-based WXY Architecture + Urban Design. Guenther is currently serving as co-chair of the Critical Buildings Committee and is on the steering committee of the New York City Building Resiliency Task Force, which provided recommendations to Mayor Bloomberg for his report. Weisz and her firm designed the East River Blueway, which aims to protect the city's eastern waterfront from flooding and damage, and advised the mayor on the Brooklyn-Queens waterfront chapter for the mayor's report.
Their advice to designers? Design for surge conditions. According to Guenther, Sandy revealed that impervious surfaces magnify the effects of surge. “We need smarter stormwater management [strategies] that channels the water to benefit the ecology,” she asserts. “Freshwater plant species were destroyed. We need to change municipal ordinances and educate property owners on landscapes with salt-tolerant plantings in order to improve recovery time.” Weisz concurs, saying that methods that better hold stormwater are a must. “Architects, engineers and landscape architects need to have a significant dialog about approaches to water, as features like green roofs, detention tanks and bioswales will help slow down the amount of water that enters the river.”
Housing must be above the flood plain to be resilient. Many homeowners now are considering raising their residences and adding wheelchair-accessible ramps and lifts on sloping yards. For existing buildings that can’t be elevated, materials that handle water better such as porcelain ceramic flooring will lessen damage. And shifting ground floor uses to retail or workshop space instead of residences will help older buildings become more resilient.
“Many multistory housing buildings near the waterfront trapped large numbers of elderly residents without lights in elevators and water service,” Guenther recalls. Because water flows downhill in New York City, the natural pressure in the system can bring water to up four or five floors without the use of electric pumps. Guenther advises multistory building owners to designate a place in the building below the fourth floor where the natural water pressure will continue to deliver water into the building during power outages. “It’s also important to retrofit elevators so that at least one elevator stays operational," she says, "and create a specific place in the building with a generator to maintain uninterrupted power so people can come and charge cell phones or radios."
Weisz says it’s critical to take a holistic approach, especially on residential streets. Neighborhood hubs such as libraries and schools with generators, can provide access to power during a storm. “A lot of innovation is coming out of single-family dwellings reaching for zero-net energy and these strategies can be examined for larger buildings,” Weisz says. “We found that people who had invested in co-generation systems and solar hot water were able to stay up and running. If large multifamily housing developments add gas or solar generators or co-generation systems, they can become a hub to serve people in nearby smaller-scale residences too.”