Hurricane Sandy tore through the New York metropolitan region on the evening of October 29, 2012. Two separate weather fronts combined with a high tide to produce astronomical tides approximately 5 percent higher than normal, with water levels at the Battery reaching an unprecedented 14 feet (measured as feet above the average low tide). The damage was enormous; impacting approximately 98,000 housing units in New York City alone.
Shortly after the storm, ideas such as tidal barriers across the entire mouth of the Hudson River and sea walls around lower Manhattan were proposed as future flood control strategies, pointing to civil engineering innovations similar to those embraced by the Netherlands and London. The costs in dollars of such strategies are enormous.
Suspicious of such large-scale solutions, a group of NYC civic organizations, under the coordinating mantle of Happold Consulting New York, undertook an assessment of the successes of various smaller scale strategies in avoiding or mitigating the impact of the storm. What they found, outlined in a report recently released to the public (www.sandysuccessstories.org), was that small, inexpensive, and relatively easy to implement measures were effective in mitigating the storm's impact with many of them providing quality of life benefits to New Yorkers during non-storm events.
The 19 case studies produced by the group touch on energy, building design, site planning, and land use approaches. Together they speak to a range of immediately implementable strategies and technologies. Concrete Plant Park along the Bronx River, for example, was reclaimed from its industrial past by the New York City Department of Parks and Recreation in collaboration with community partners.
Although its primary purpose was to provide more recreational space for the neighborhood, the carefully designed park increased the area's capacity to detain water and created a buffer that protected the surrounding communities from flooding. Equally effective was the Lower East Side People's Mutual Housing Association's disaster preparedness plan; clear procedures that had been put in place for their buildings prior to the storm that reduced damage to mechanical systems and ensured business continuity during and after the event.
The case studies also include a number of what might be termed serendipitous successes; such as a residential high-rise at 4705 Center Boulevard in Queens, where contamination at the site required the developer to build at higher elevations than he might otherwise have done. But they also include very deliberate ones like the green infrastructure component of the city's sustainability plan, where the creation of small vegetated triangles, curbside bump-outs, and trees helped reduce flooding and pollution outflows into the city's waterways.
Some of the solutions were initiated by people without any outside prompting: e.g. one beachside community relied on volunteers to help build and plant a double dune system to protect their homes. Others, including a new development in Queens known as Arverne by the Sea, were forced upon developers by increasingly sustainable local planning regulations. In the future, however, there is little question that it is the government's responsibility to manage the planning of the built environment with an eye to the new climate based challenges.
Whether or not New York City and State have the capacity to implement these ideas is unclear. But if the enthusiasm of the groups behind Sandy Success Stories remains in place, any new mayoral administration will think twice before endorsing controversial, expensive and risky civil engineering solutions at the expense of more doable, less expensive, and more beneficial ways of adapting to the new environmental realities we face.