Mayor of Atlantis

Illustration by Bryan Christie Design

Michael Bloomberg’s $20 billion to-do list for repairing the coastline may seem radical and huge, more a fantasy of a water-adapted metropolis than an actual plan. Yet almost every proposal in it is a modest version of a strategy that other parts of the world—the Netherlands, mostly—have already tried, often on a far grander scale.

1. Storm-Surge Barrier
As seen in: The Afsluitdijk, The Netherlands (inset) The instinctive response to an invading sea is to keep it out, and some engineers have called for immense floodgates to barricade New York Harbor completely. The Dutch have built even more pharaonic fortifications: In the thirties, they sealed off a large bay that once drove from the North Sea deep into the heart of the country, and added higher, stronger defenses after a 1953 storm burst through several dikes, killing 1,800 people in Holland. But those require many billions of dollars and decades of dedication, and don’t come with guarantees. Bloomberg has proposed smaller, more targeted barriers, including this one near the sewage-treatment plant at Newtown Creek. Photo: Courtesy of the NYC Mayor’s Office; Frans Lemmens/Getty Images (Afsluitdijk Dike)

3. Seaport City
As seen in: HafenCity, Hamburg (inset) The most controversial and dramatic item in Bloomberg’s wish list is a new high-rise cluster on new land just south of the Brooklyn Bridge. Environmentalists fear the effect on sea life and currents; preservationists object to enfolding the old seaport in towers. Yet from its start, New York has stretched its natural coastline; only after the World Trade Center and Battery Park City were built on fill was the practice essentially stopped. In other cities, this new proposal would seem modest. Tokyo has colonized large parts of its harbor, and in Hamburg, Germany, the old port is being gradually transformed into HafenCity, a gleaming new district jacked up well clear of the projected floods. Photo: Courtesy of the NYC Mayor’s Office; Alamy (Hamburg)

4. Dune and Beach Nourishment
As seen in: Zandmotor, The Netherlands (inset) The Bloomberg plan recognizes the importance”and the fragility”of dunes. But replenishing the sand that waves and wind keep scouring away from beaches is a pricey way to combat nature: Far Rockaway is already the most expensive beach in America, and New Jersey property owners have griped about what Chris Christie’s Maginot Line of dunes is doing to their views. To get around both problems, the Netherlands created the Zandmotor, or sand engine, an artificial thumb of beach sticking out into the North Sea. Vast quantities of sand sucked up from the ocean floor were dumped in place in 2011 and turned over to the wind, tides, and currents, which should gradually redistribute the sand into a natural reinforcement. Photo: Brendan McDermid/Reuters; Rijkswaterstaat/Joop van Houdt/Alamy

5. Wetlands and Catch Basins
As seen in: Water Plaza, Rotterdam (inset) It can be hard to accept that the way to deal with floods is not to repel them but to calm waves, let the water in, then gradually release it. That’s why the city’s plan advocates soft-edged parks, marsh grasses, reefs, and rocky revetments for places like Jamaica Bay and Coney Island. In Rotterdam, a public area of playgrounds and soccer fields fills up during heavy rain; a day or two later, the plug is pulled, and the contents drain harmlessly away. For New York, the firm Architecture Research Office has proposed a system of porous, absorptive streets, and Joseph Wood, the winner of a design competition for the East Side waterfront, suggested cutting canals in from the East River, making Turtle Bay genuinely amphibious. Photo: Courtesy of the NYC Mayor’s Office; Courtesy of the Rotterdam Climate Initiative (Water Plaza)

Mayor of Atlantis