Urban Density = Safety?

A friend recently sent this article from The Atlantic to a group of college friends, most of whom are employed in the design and construction sectors. The article’s main thrust is to promote the idea that population density makes for an inherently safer built environment in the event of a natural disaster. As a New York-based engineer, my friend has spent better part of the past eleven months rebuilding parts of the city devastated in Hurricane Sandy. His take on the article was less than enthusiastic.

In a short, but not particularly unusual rant (he speaks in diatribe, it’s why we get along), he all but accused the author of knowing nothing. Nada. Zip. Devoid of the inclination to form semi-intelligent thoughts. His critique was a bit harsh, but not without merit. My friend—whose intelligence the validity of this entire article relies upon—came armed with a slew of points.

The first thing that you need to know about the article is that its author, Vishaan Chakrabarti, isn’t exactly a slouch. He’s an architect that boasts the type of resume filled with positions and accolades that are simultaneously impressive and make you want to gag. Currently an associate professor and director of the Center for Urban Real Estate (CURE) at Columbia University, he is also one of two principals at SHoP Architects not linked by marriage or blood, a former Executive Vice President at the Related Companies, and a former Associate Partner at Skidmore, Owings & Merrill. In 2001, he was named one of Crain’s 40 under 40.

Chakrabarti has the credentials to put forth claims on architecture and the city, especially those that cut across urban planning issues in New York City. His first job was in the City’s Office of Planning. As a practitioner, he is now involved with SHoP’s mixed-use projects, including a few on the Brooklyn side of the East River waterfront. He also has a new book, A Country of Cities: A Manifesto for an Urban America,that he is actively promoting. You can probably see where this is going…

The article’s headline makes the type of bold claims that his publisher is sure to love: Urban density makes us safer. The problem with Chakrabarti’s article is that the author never addresses his title’s central claim. Are there studies in which density is positively correlated with safety in the event of a hurricane? Do the events of Sandy bear this out? And how is that measured? Deaths? Injuries? Recovery time? Instances of disease? Does density’s safety factor vary by disaster type? The list of questions could go on, in part, because Chakrabarti offers few clues and even fewer answers. Instead, he provides readers with a slew of meaningless boilerplate and positivist rhetoric. The following selection is an instructive, but hardly exclusive sample of such vapidness:

We must continue to develop our cities—even in those areas that lie in potential flood zones. There are 300,000 New Yorkers living in our most vulnerable flood zones, with even more development being planned in those very zones. While this reality has been subject to criticism, we should no more abandon those plans than we should retreat from Lower Manhattan, Red Hook, or DUMBO. We must find “both-and” solutions that allow high-density, mixed-income, transit-oriented waterfront development able to withstand climate-related risks. If we abandon waterfront areas, for example, we risk further limiting supplies of housing, which will make the city unaffordable to an increasing number of people.

It all sounds good, though it lacks even the smallest suggestion about how the city might safely accommodate residents in the city’s most flood prone areas. Even more frustrating, its a position I’m inclined to get behind if there were even a hint of evidence in support. Notably absent is any explanation why population density is a stronger predictor of safety than another very basic tenet of architecture and urban planning: site selection.

And this, in particular, was why my friend was so incensed. As he has worked on various relief projects for the past eleven months, the parts of the city that he has visited aren’t the city’s low-density areas, they’re the low-lying areas. I’ll let him put it succinctly:

You could hand pick the densest part of Manhattan and plop it at Breezy Point and I’d imagine it would be even less functional after Sandy… That’s why Hoboken, basically at sea level and the fourth densest city in the US was destroyed for months while suburban Westchester came out relatively unscathed.

Downtown Brooklyn: On a fucking hill. Harlem: On a fucking hill. Battery Park: WTC landfill from the 70s with a sea wall and higher elevations than lower Manhattan. (All of those were protected by the harbor where the storm surge was many feet less). Staten Island & Breezy Point: The fucking beach, out in the ocean, at sea level.

To rephrase the already obvious: All things being equal, density doesn’t mean a whole lot when things aren’t going your way. Anyone who takes more than a few moments to think about this problem is probably going to arrive at a similar conclusion. It’s not as if New York’s pre-war architecture was constructed to survive major storms and many of the city’s unreinforced masonry buildings are ill-prepared for other disasters like seismic events.

If one were to attempt to glean a kernel of insight from the article, it would be by ignoring the title’s claim altogether and evaluating its sentiment. For one, the article says much more about the nature of recovery than it does about safety. High-density, mixed-use neighborhoods tend to command the type of infrastructural redundancies that not only provide services to a much larger group of people over smaller geographic areas, but allow at least partial restoration of services in a relatively short timeframe. For most people who experience the aftermath of a major storm, it’s the return to normalcy that takes it greatest toll. Further, the article hints that storms like Sandy are only going to become more common as global warming trends continue to advance. The inevitability of these storms places additional importance on advancing technology, engineering and policy measures to ensure that architecture and the urban environment are prepared to withstand them. Developing more stringent building codes, for example, may need to be a priority in coastal cities that are not historically subject to hurricane-like storms.

I’m not positive that dense patterns of urban development can be boiled down to a unified safety paradigm. I tend to assume that in such instances, there’s only so much that can be done before extreme precautionary measures become disruptive to daily life. And if such safety restrictions are one possible response to Sandy, the elimination or marginalization of developable coastal lands in the city could be another, potentially more significant result.

This is Chakrarbti’s real objective: To preserve the development potential of riverfront property, and in the process, maintain the city’s accessibility to residents of all income levels. It’s an old argument, but also one backed up by the simplest supply-and-demand logic stating that an increase in the supply of housing will drive down housing costs. Further, over the long-term, housing developed for high-income tenants will trickle down and become the affordable housing of tomorrow. Put another way, Chakrabarti’s article is an argument to do the right thing even if his reasons are not entirely supported by facts. As someone planning to move to New York City in the near future (to practice architecture, no less), the prospect of a lower rent and better housing options sounds swell.

It’s the title that Chakrabarti should have given to his article.