Monday, February 18, 2013

Preparing for Future Major Storms


James T.B. Tripp

The FDR Drive at 81st Street flooded during Superstorm Sandy. Photo by Gothamist

Sandy hit New York City, Long Island, New Jersey and parts of Connecticut with a Katrina-type ferocity for which this region was not well prepared. Its effects were felt over a 1000-mile wide area. Its storm surge was over 14 feet in many coastal areas, higher than most forecasts and 3-4 feet higher than any former surge. Coastal flooding in Staten Island, the Rockaways and lower Manhattan was profound, with destruction of and damage to coastal buildings and public infrastructure, prolonged power outages and scores of deaths. New York City is obviously vulnerable to storm surge since it alone has some 550 miles of waterfront. Two of its five boroughs are separate islands, and two others,  Brooklyn and Queens are part of Long Island. Coastal New Jersey and Long Island have extensively built-up barrier islands and lowlying coastal mainland communities. Large portions of Manhattan are built on low-lying fill. This includes areas around East 96th Street that were marshy up until the end of the 19th century; flooding due to Sandy reached almost to Second Avenue on East 96th Street.
The East 63rd Street pedestrian bridge on the East River Esplanade as Superstorm Sandy moved in on October 29. Photo by Ruth Fremson of The New York Times

Sea level is rising, and could go up at least one foot during the next 20-30 years even without the collapse of any major ice sheet. The International Panel on Climate Change that uses a range of climate models predicts intensification of storms surge that could exceed Sandy’s by 3 or more feet? Given global warming, it is important that New York City, New York State, New Jersey and Connecticut use available federal, state, local and private resources to make this region and its coastal areas as resilient as possible to future storms. In addition, these three states should accelerate actions, jointly preferably, to reduce their CO2 emissions and thus their contributions to global warming. The Mayor’s Office of Sustainability and some New York City agencies, such as its Department of Environmental Protection, have done extensive planning for this new warmer world. The Mayor foresightedly ordered evacuations of low-lying areas in the City during both Irene in 2011 and Sandy.  

The pre-Sandy CIVITAS East River Esplanade ideas competition produced designs that incorporated ways to moderate storm surges. This concern was also seen in the leading competitive designs that the Museum of Modern Art showed in its “Rising Currents” exhibition. Wetlands and oyster reefs can moderate storm surge, but will have only a modest effect on a 14-17 foot surge. In some places flood walls might be considered, but they can be unsightly and serve to redirect rather than absorb flood waters. 
An underground transformer in front of Metropolitan Hospital at First Avenue and East 96th Street flooded with salt water, causing a lot of steam. The hospital was equipped with generators and continued to operate. Photo by Sune Engel Rasmussen, published by The Uptowner
While it is tempting to think that large-scale storm surge barriers located somewhere in Long Island Sound and New York City’s Lower Harbor can control nature’s future fury, the City and the three States would be ill-advised to plan and act on the assumption that such barriers would be built any time soon, although they may be wise to establish a process for thinking about the basic parameters of such barriers for the mid-century and not simply depend on the Army Corps of Engineers. They are complex and very expensive engineering works with major environmental consequences. They also redirect rather than eliminate storm surge so that coastal areas upstream of the barriers will experience higher flood elevations than would otherwise be the case. 

One solution to mitigating the effect of storm surges lies in designing, or retrofitting, public infrastructure and buildings to accommodate episodic major floods. New York City and other coastal areas will have to think about where they want storm surge waters to go in low-lying areas, as well as where they don’t want the waters to go. Public assets such as the subways, railroads, highways, hospitals, water and wastewater, communication and electric utility systems, and private high-rise commercial and residential buildings will have to be flood proofed. Investments to radically improve the energy efficiency of high-rise and individual buildings, coupled with back-up decentralized solar, wind or other power sources that can function independently of the central power grid, all part of the “smart grid” of the future, should be aggressively promoted. 

Individual structures outside of densely populated urban areas in New York City, Long Island, coastal New Jersey and Connecticut should be elevated to a new storm surge standard. In such areas, man-made sand dunes may play a useful role so long as they are properly sited where natural processes would place natural dunes, not right along the beachfront. Federal, state and local response programs should provide funds to buy out private properties in vulnerable areas as an option to the owners who otherwise would face high building-elevation and insurance costs or whose rebuilt structures would impede wise siting of any man-made dunes. Building codes will have to be revised to incorporate flood and energy resiliency measures. Insurance companies need to fine-tune their assessments of storm and flood risks associated with individual assets and structures, depending on what resiliency measures the owners adopt. As former Governor Pataki proposed, the electric utilities should gradually put power lines underground in areas with the density to justify such action. 

Taking these kinds of measures in the many different kinds of settings found in the tri-state region will cost tens of billions of dollars. Electric utility, MTA, water and wastewater, and communication system rates will inevitably rise to finance these measures. The federal government may come through with billions of dollars in emergency appropriation to help cover the cost of post-Sandy clean-up, damage compensation, and perhaps even future accommodation measures. New York City and the three states in our region should use these resources wisely to assure future resiliency to future storms powered by global warming. If we plan and prepare well now, we and other coastal areas of the country may not have to seek comparable federal assistance in the years ahead. 


James T.B. Tripp is Senior Counsel at the Environmental Defense Fund and Executive Vice President of CIVITAS. For more information on the CIVITAS Reimagining the Waterfront project visit: www.reimaginethewaterfront-civitas.com


To read the complete spring 2013 issue of CIVITAS News, visit http://civitasnyc.org/civitas-newsletters/

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