Assessing Resiliency and Risk: We Can’t Save It All
Conversations around resiliency today seem to imply that planners and designers might be capable of—might even be expected to—save every building and public space at risk. The sad truth is, however, that we cannot, and perhaps we should not. Climate change and its attendant sea level rise will radically redraw urban edges, forcing us to make difficult decisions. Even if we had the vast sums of money required to protect the precarious status quo, that might not be enough to stave off the inevitable.
So, then: What are our priorities? How do we choose what to save? How do we responsibly chart this uncertain future? I believe the answers to these and similar questions should begin with an honest assessment of three essential considerations:
(1) Consider the useful life of buildings, structures, and public spaces. When thinking about how to apportion funds for resiliency and risk assessment, the “useful life” of a facility should be a key determinant in what is saved (note that I do not say “protect,” a potentially more accessible goal). Every structure and public space is designed to have a “useful life”: an anticipated life span based on design and construction. This is usually determined by clients, but it should be a significant consideration for designers, too. For example, hospitals are designed for, at minimum, a 100-year existence, even if internal mechanical systems require upgrading to keep pace with technological advances.
Sadly, housing—particularly standalone and attached residences—typically falls far below this threshold. One of the major challenges for this sector is that we largely construct these buildings with concrete, which is also true for infrastructure. Exposed-concrete structures, such as bridges and tunnels, have an approximate 50-to-60-year life span. In other words, New York’s Robert Moses-era infrastructure has now reached the end of its viability. Steel structures are also limited, if they are not regularly inspected and monitored for rust and deterioration. As a result, in the future, hospitals located near or in flood zones might warrant saving, but at-risk housing and infrastructure might not.
(2) Evaluate their worth to society. Every structure and space should be considered in terms of the value to people of its ability to withstand the impacts of a physically disruptive occurrence—i.e., the ability to recover from a traumatic event—and supported accordingly. Critical facilities include hospitals, food storage and delivery systems, and infrastructure such as bridges, roads, and telecommunications that provide evacuation and emergency response opportunities. Among these, facilities considered highly critical should be evaluated based on their capacity to integrate redundant systems that will enable them to function immediately following a catastrophic event. For example, following Hurricane Sandy, a number of major facilities along New York’s Upper East Side “Hospital Row” lacking in-built redundancy had their mechanical systems overwhelmed by flooding, which resulted in weeks of disruption to crucial medical care.
Considering public spaces, one might ask whether parks, for example, are “critical infrastructure.” Clearly, they are not vital to one’s ability to recover or survive a catastrophic event, but are they critical in terms of daily life? I would argue that they are. So what level of risk are we willing to accept for parkland? And if this parkland—125 of New York City’s 525-mile-long coastline, for example—is within a zone of vulnerability from storms and sea level rise, then will we slowly see the disappearance of it as seas rise and storm frequency accelerates? Should we be planning to replace that parkland elsewhere? Should we relocate (“retreat”) people from coastal communities so that we can build replacement parks at a higher elevation (a highly unlikely option)? Or do we simply accept this “taking” of parkland by natural forces? On the other hand, when is a “floodable park” no longer usable? When it floods monthly, or weekly, or diurnally with the tide? All of these elements come into consideration when evaluating the investment value of resiliency interventions in these spaces.
(3) Officially categorize structures and spaces and take action based on risk management and climate change considerations. The NYC Mayor’s Office of Climate Policy and Programs, to which I am a contributor, suggests that, going forward, buildings and infrastructure should be formally categorized as to their “criticality,” and that these rankings should result in a level of responsibility on the part of clients. Presumably this would apply to public entities, but not always. The NYC Economic Development Corporation recently issued a request for proposal to developers for the reconstruction of the Bronx’s Hunts Point Produce Market—which delivers fresh produce to 22 million people along the Eastern Seaboard—to ensure that the project provides a facility to the public that is sufficiently robust. This will guarantee that through redundant systems and good site planning, it will withstand, or be able to quickly recover from, a catastrophic event. In the absence of such a system, food supply would be disrupted for days, and the economic loss from spoiled food products would be in the millions of dollars.
We need a different paradigm. The bottom line is that we, as designers and as a society, particularly in cities with vulnerable coastlines, cannot afford to save our entire built environment as it’s currently constructed. In New York, we’re unlikely to become a city of “climate refugees”—at least, not in the immediate future. So how does a coastal city of almost 9 million adapt to climate change?
The process will necessitate a multipronged approach requiring virtually every city agency to advance its thinking. If retreat and relocation are to be taken seriously, for example, we need to start looking at upzoning areas of higher ground. We need a different strategy to deal with our sewer systems, which determine street grades; streets with sewer outfalls that dispose of stormwater into our rivers are frequently low-lying and serve as conduits for inland flooding. And we need to take a comprehensive look at our parkland to identify where our recreation resources will disappear over the next 50 years and whether they can be replaced or should be made resilient.
But these suggestions merely reinforce a siloed approach. Ultimately, the city needs an integrated set of policies that can cut across all agencies, ensuring that every dollar spent on resiliency results in multiple long-term benefits.
Featured image: Waterfront Esplanade, The Stavros-Niarchos Foundation, David Rockefeller River Campus, Rockefeller University. All photos courtesy of MNLA.
Signe Nielsen is a founding principal of MNLA. She is also a professor of urban design and landscape architecture at Pratt Institute in both the graduate and undergraduate Schools of Architecture, and serves as the president of the Public Design Commission of the City of New York.