Is New York’s 'Bold' Plan to Fight Rising Sea Levels a Model for Other Coastal Cities?

By the end of the century, one in five streets in Lower Manhattan could be flooded every day.
by | May 2019
Aerial of Manhattan
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A chorus of questions greeted New York City Mayor Bill de Blasio when he announced in March that he wanted to make the island of Manhattan bigger by extending it 500 feet into the East River, in order to better protect the Financial District and nearby areas from sea level rise.

What, people wanted to know, would go on the new land? Why does de Blasio favor this approach, after scuttling previous plans to build a berm at the edge of East River Park? How will the city avoid such a massive project from getting bogged down in environmental reviews, community hearings and inevitable lawsuits? Would protecting Manhattan come at the expense of Brooklyn and Queens? Above all, they asked, how would New York pay for the $10 billion project?

But Corinne LeTourneau, the former director of special projects for New York and now the head of North American operations for the Rockefeller Foundation’s 100 Resilient Cities program, says she was struck by the project’s “boldness.” That’s something she says is in short supply these days, as cities start coming to the realization that their neighborhoods and infrastructure will be affected by climate change. “I hope this isn’t a New York-only solution,” she says. “They’re trying to think from a new perspective. My hope is that we’ll see more of this boldness, even in cases when many, many, many other solutions and things that have been studied will not work.”

In fact, she notes, Boston Mayor Marty Walsh recently unveiled an ambitious “neighborhood by neighborhood” plan to protect the areas around Boston Harbor. His plan includes creating 67 acres of green space, adding landfill in places, erecting seawalls and adding land-based barriers. Walsh also called for elevating certain streets and other structures. 

Meanwhile, the city of New Orleans is using federal grants to help make Gentilly, one of its most flood-prone neighborhoods, more resilient. The city is creating parks and repurposing street medians to include water features that will collect rainwater and prevent flooding.

In New York, de Blasio noted that the city is already taking measures to protect its coastline in other places, using federal money that started flowing after Superstorm Sandy inundated the city in 2012. Other parts of Manhattan would be protected by removable barriers that could be anchored in place as storms approach. “But there’s one part of this area that will prove more complex, more costly, to defend than all the others combined,” he wrote in his announcement. “South Street Seaport and the Financial District, along the eastern edge of Lower Manhattan, sit so close to the sea level -- just eight feet above the waterline -- and are so crowded with utilities, sewers and subway lines that we can’t build flood protection on the land. So we’ll have to build more land itself.”

The city predicts that, by the 2050s, more than a third of Lower Manhattan would be at risk from a storm surge. And by the end of the century, the city says, the sea level rise in the area would be more than 6 feet; one in five streets in the neighborhood could be flooded every day -- even under sunny skies -- by the rising tides. “We’re going to build it,” de Blasio said, “because we have no choice.”

The mayor says the federal government should pay for some of the improvements, because projects of that scope are beyond the means of states and local governments. It makes no sense, he argues, that the federal government will help communities recover after a disaster but not help them prepare before a disaster occurs, when the costs would be much cheaper. Still, even the mayor acknowledges that help from Washington won’t be coming anytime soon.

LeTourneau says many resiliency projects never get off the drawing board because of questions of financing; too often those projects never even get to the drawing board. But she says cities shouldn’t dismiss expensive-sounding projects out of hand. In many cases, projects to build resilience offer many simultaneous benefits -- new parks and green space, better water quality, more attractive neighborhoods -- that could each attract their own sources of funding.