Invited by Bowman and his colleague Douglas Hill, two European engineering firms have drawn up proposals for walling most of New York off from the sea, at a price just above $6 billion.
Before the storm, Mayor Michael Bloomberg’s administration had said it was working to analyze natural risks and the effectiveness of various coast-protection techniques, including storm-surge barriers. But officials had noted that barriers were only one of many ideas, and they have often emphasized more modest, immediate steps the city has taken, such as installing floodgates at sewage plants and raising the ground level while redeveloping a low-lying area in Queens.
“It’s a series of small interventions that cumulatively, over time, will take us to a more natural system” to deal with climate change and rising sea levels, Carter H. Strickland, the city’s environmental commissioner, told The New York Times this summer.
Engineers know this approach as “resilience” – essentially, toughening the city piece by piece to make it soak up a surge without major damage. But the European engineering firms whose barriers protect the Netherlands and the Russian metropolis of St. Petersburg see this as unrealistic, given the vast amount of expensive infrastructure that underpins New York.
“How does New York as a city retreat into resilient mode? It’s just difficult to see how that would happen,” said Graeme Forsyth, an engineer for CH2M Hill in Glasgow, Scotland.
Sandy sent a record 14-foot storm surge into New York Harbor, flooding subway tunnels and airports. It forced the closure of the stock market for two days, the first time that’s happened for weather-related reasons since 1888. There’s no estimate yet for the cost of the devastation in New York City, but forecasting firm IHS Global Insight put the cost of the damage along the coast at $20 billion, plus $10 billion to $30 billion in lost business.
Forsyth has worked on St. Petersburg’s barrier, which consists of 16 miles of levees and gates shielding the city, built on what was once a swamp, from the Baltic Sea and the river Neva. The centerpiece of his firm’s early-stage proposal for New York is a levee-like barrier that would stretch five miles from the Rockaway peninsula in Queens on Long Island to the Sandy Hook promontory in New Jersey. The barrier would stop a surge of 30 feet, twice the height from Sandy. Gaps would allow ships, river water and tides through, but movable gates could close off all of New York Bay from the Atlantic when necessary. The barrier would protect most of the city, with the exception of Rockaway itself. It would also shield parts of New Jersey.<< previous 1 2 3 next >>