It is estimated that Hurricane Katrina cost nearly $100 billion. Government reports suggest that a precisely aimed Category 4 hurricane could exact five times that amount in damages on New York City. Even a less severe storm could cost the subway system alone $58 billion. As sea levels rise, that number could swell to $84 billion.
"You thought Hurricane Katrina was bad," said Colonel John R. Boulé II, district commander of the U.S. Army Corps of Engineers New York District. "But if a hurricane like that hit New York, Katrina would be a day in the park." New York City has more than 520 miles of coastline -- more than any other city in America. As the hub of the largest regional economy in the United States, it produces over $600 billion a year, or four percent of the country's GDP. New York Harbor, one the nation's main trade gateways, manages over $350 billion in imports and exports. Plus, the city is home to the headquarters of 45 Fortune 500 companies.
It's statistics like this that haunt Klaus Jacob, a senior research scientist at Columbia University's Lamont-Doherty Earth Observatory, who has studied the city's vulnerability to flooding for years. Mayor Michael Bloomberg's plans to prune the city's greenhouse gas emissions (think bike sharing) will no doubt minimize the role it will play in global warming, says Jacob. But it cannot reverse a process like sea level rise, which has been afoot for quite a while.
Leaning back in a chair with orange tweed upholstery, Jacob, a 76-year-old German native with a wooly beard and slate-blue eyes, glances at a subway map pinned above his desk. If the ice that blankets Greenland and Antarctica melts more quickly, he says, New Yorkers could see more than four-and-a-half feet of sea level rise in the next 70 years. By then, New York City will be seven degrees warmer and will have the climate that Raleigh, North Carolina, does today.
Today, more than 200,000 New Yorkers live within the 100-year flood zone. The areas at risk include some of the city's most vibrant neighborhoods, critical infrastructure, and hundreds of thousands of jobs. Lower Manhattan, the neighborhood at the southernmost tip of the island that houses Wall Street and the New York Stock Exchange, occupies some the lowest-lying elevations in the city. "We've invested billions in rebuilding the World Trade Center site, said Jacob in March. "And SLOSH says the site will be flooded." This week, those predictions too bore out when seawater gushed into the cavernous construction pit at Ground Zero aptly named "the bathtub."
Nonetheless, many coastal neighborhoods in New York are in the midst of extensive shoreline development. According to the mayor's master plan for the city, local waterfronts -- particularly in the outer boroughs -- are due for a growth spurt. As is the case in Brooklyn (think Fairway and Ikea), some have already begun to see construction of new parks, housing and commercial buildings near the waters' edge. According to Jacob, all of this constitutes millions of dollars of spending in a floodplain. "It'slike Sisyphus," he said. "Rolling rocks up to the top of the hill just to see them slide back down."
Bloomberg's plan also considers schemes to hold back the advancing sea. Ideas range from the installation of wave attenuators -- long, floating piers that can absorb the energy of approaching water -- to "soft edges," or permeable surfaces, like wetlands, beaches, and reefs, designed to reduce the speed and force of incoming waves. Planners are experimenting with simpler fixes too, like building rims around the city's rooftops to trap rainwater, and moving critical equipment to higher elevations.
A more extreme proposal is that New York ring itself with giant concrete seawalls -- called storm surge barriers -- for protection. The mobile bulwarks would operate similarly to the ones on the Thames River in London, conceived after the North Sea flood of 1953 killed hundreds of residents and forced thousands more from their homes. Like a giant gate, New York's barriers would remain open in fair weather so that ships could navigate through, but close to shelter the city during storms. At their high points, the structures would rise 30 feet above the water. They would require decades of study, and could cost upwards of $10 billion dollars to build.
Jacob believes that large-scale projects like storm surge barriers offer a false sense of security. Since New York is located on an estuary, he says, they could never protect all of the city's coastal property. What's more, they would be expensive to preserve in the long run, and as sea level rises, they would need to be raised.
"There will be a brutal, wet awakening for the entire city," Jacob said, arguing that someday, New Yorkers will likely have to retreat from the coastlines. New York was lucky that Irene was only a 30-year storm, he said months ago. But a city can't rely on luck. "Before the year 2000, we had one bullet in a revolver that had a hundred chambers; every year we pulled the trigger, and hoped we wouldn't get hit. By the end of the century, we'll have at least 10, maybe 20, bullets in those 100 chambers, and we'll pull it every year. How many years can we expect to get play without getting shot?"
Slowly, things do happen, whether by mistake or design. On an afternoon in April, while the Yankees played the Red Sox in their 100-year anniversary game at Fenway Park in Boston, O'Grady's engineers labored across the Harlem River from the Bombers' empty stadium. A stretch of seawall had fallen into disrepair, and the 148th Street subway station and train yard were prone to flooding. O'Grady had recently secured funds to build a new wall -- and even raise its height -- and now a barge loaded with sheet piles was bobbing in the brackish water. After a construction crew demolished the old, spalling concrete, they set to work building a new barrier that transit officials hope will keep the Number Three Line dry.
According to Jacob, the new sliver of seawall pales in comparison to what the transit authority will need to do in the years to come. But senators and representatives from districts upstate have traditionally been reluctant to fund the New York City subway system, said Jacob, and there is still little prospect that Albany will approve a large rail project.
Dutta agrees that American political institutions display an anti-city bias when it comes to resource allocation. The country has been disinvesting in public transportation for generations, he said. "The New York region is riding a rail system that its grandparents and even its grandparents' grandparents put together. For 70 to 75 years, there's been no major reinvestment in running it." Think of it this way, Dutta explained: More people pass through Grand Central Terminal every day than live in the state of Wyoming, but Grand Central does not have two senators.
Ensuring the long-term survival of the subway system will require a radical shift in American values, said Dutta. Its longevity depends on society's belief in public transportation as a public good. "Public transportation reduces carbon dioxide," he said. "Carbon dioxide causes global warming, global warming brings water into the public transportation system, and the result is the reduction of public transportation. It's a vicious circle and it's not well understood." Two-thirds of New York state's residents live in the MTA service area, he said, but there is a national narrative about highways and cars and roads that is much more powerful. Right now, federal transportation dollars are split 80/20 in favor of roads and highways. "If you want to solve the problem of climate change, we have to start reversing that split."
That day in April, a century after Boston won its inaugural game at Fenway Park, the Yankees defeated the Red Sox by four runs. Below the steel superstructure of the Harlem River Drive in New York, the construction crew finished up its work on a thin patch of concrete. I stood and watched as a crane with a tall red boom and an American flag at the base turned in its cradle aboard the barge.
From shore, a transit worker shouted instructions to the cab's operator, but they were lost amid the roar of traffic overhead. Slowly, the boom dipped. Its hook caught the end of a heavy steel beam, hoisted it into midair, and sank it down in the muck below the surface of the water.