Why is New York City so prone to flooding and how do other major cities prevent it?
NEW YORK -- Last week's historic flooding in the New York City area has raised three key questions: Why is New York so flood-prone, what's being done to prevent it and what are other cities doing?
Where you see water pouring into one Queens subway station, ecologist Eric Sanderson sees something else.
"It's a place that used to be a salt marsh," said Sanderson.
And where you see flooding in South Williamsburg, "That was Wallabout Creek," said Sanderson.
Sanderson, an ecologist with the New York Botanical Garden, spent years mapping out and visualizing what New York City looked like before and after it became a city.
"I know why these places are flooding. Because they're all places that used to be wetlands or streams or ponds in the past and we built city on top of them," he said.
Scientists say those areas are even more flood-prone thanks to the increased heavy rainfalls caused by climate change.
The New York State Department of Environmental Conservation honored several communities Monday for reducing emissions, which it hopes will slow the effects of climate change.
"If we do everything we can to reduce emissions globally right now, it will take decades to begin reducing the average global temperatures," said Basil Seggos, commissioner of the New York State Department of Environmental Conservation.
Much of New York's infrastructure was not built to handle the kind of rain we've seen.
"The MTA has invested billions of dollars in resiliency projects that again demonstrated their value in recent days when the latest 'thousand-year storm' dropped a historic amount of water on the region in a short period of time—and the subway system and commuter railroads were just partially impacted and only for a matter of hours," said MTA spokesperson Michael Cortez.
The state and city have invested billions in flood prevention, a concern all over the globe.
In Bangkok, for example, subway riders walk up a staircase before they walk down, a design aimed at keeping water out.
"One of these chronic places where there's flooding, it's not gonna help a whole lot," said Upmanu Lal, an engineering professor at Columbia University. "So we need a strategy where we at least install pumps there so that we could proactively pump the water in those locations to other areas that are not yet flooding."
The city of Copenhagen has earned praise for redesigning parts of the city to hold water from heavy rainstorms.
New York City is planning projects with that same goal, including a sunken basketball court designed to hold stormwater at a NYCHA property in Southeast Queens.
"My only criticism, if I might, is that it's just not enough. They're trying to work in the public domain. Some things are gonna have to happen on private land," said Sanderson.
The city said it plans to break ground on that project in the fall.
NYU is also working with the city on a place to create a network of hundreds of sensors to help detect flood risks in real time.
