ROBERT SIEGEL, HOST:
For New York, last year's hurricane was a painful reminder that the city is surrounded by water. It has more than 500 miles of coastline, from the beaches of Staten Island and the Rockaways, to the banks of the Hudson and East Rivers and beyond. There is little dispute among scientists that rising sea levels will increase the threat of flooding. And now, as hurricane season begins again, there's a spirited debate about how the region should prepare for that threat.
NPR's Joe Rose has this story about two very different visions for New York's future.
JOEL ROSE, BYLINE: The view of lower Manhattan, with skyscrapers soaring right out of New York Harbor, is one of the most recognizable images of the city. Stephen Cassell(ph) wants to change it.
STEPHEN CASSELL: We are looking right out towards the Statue of Liberty right now and we see a series of wetlands and sort of very slender barrier islands...
ROSE: Cassell is an architect. His firm re-imagined this section of New York's waterfront for a museum exhibition in 2010. But their plans didn't get much attention until Hurricane Sandy hit last fall. I met Cassell near the Staten Island ferry terminal in Lower Manhattan, where tanker ships and tour boats dot the harbor. Right now, the concrete sidewalk ends abruptly where the water begins.
But in Cassell's vision, the land might give way more gradually to parks and wetlands that would help absorb the impact of storms and the hard pavement of downtown Manhattan might be replaced with something softer.
CASSELL: We're basically proposing an absorptive street bed that would absorb the water and then have channels that would channel it back off to the edge of the island, into the wetlands which would then filter out pollutants.
ROSE: This is one vision of New York's future, a city that's more resilient after a major flood but it's not the only one.
MALCOLM BOWMAN: My response to that is that's not good enough. It's not sufficient against another major event like Sandy.
ROSE: Malcolm Bowman is a professor at the State University of New York at Stony Brook. He doesn't object to wetlands or absorptive streets, but Bowman argues we have to think it bigger, a lot bigger. He wants to see a set of massive offshore floodwalls, one set of barriers that would span the harbor between New Jersey and Long Island, and another between Queens and the Bronx.
BOWMAN: That would provide protection for all of Manhattan, the outer boroughs of Brooklyn and Queens, Staten Island, the three major airports - Newark, JFK LaGuardia - and everything that's inside that circle of protection, that is the only long-term solution if we're going to stop this happening again.
KLAUS JACOB: Is that a permanent solution? No, because sea level keeps rising.
ROSE: Klaus Jacob is a climate scientist at Columbia University. Jacob says barriers are problematic. They're expensive and we don't really know how much the sea is going to rise.
JACOB: With sufficient sea level rise those barriers will become dysfunctional. So we will have then to do everything that we could do now, or start to do now, that we have to do eventually if we have the barriers.
ROSE: Instead of fighting to keep the water out, Jacob and others argue it may be more practical to just let it in. That would likely mean retreating from some neighborhoods along the shore. And in areas that are too densely built to abandon, like Lower Manhattan, it would be accepting that the storm surge which accompanied Sandy could become a regular event.
JACOB: That means the water once in a while floods the streets. And I can foresee sort of like high lines connecting the buildings above ground, above the street level. And we'll look down onto Wall Street when the water comes and the ducks float around down there, and we still can get from building to building.
ROSE: Jacob's vision may not be as farfetched as it sounds.
HARRY BRIDGWOOD: All of this was new. All of this was brand-new. I mean let's take a little walk.
ROSE: Harry Bridgwood runs 55 Water Street, a massive office building in Lower Manhattan. As the name suggests, the building sits right up against the East River which, during Sandy, flooded into the lobby and basement. The cleanup took months and cost $135 million. Bridgwood shows me room after room of brand-new electrical equipment in the basement.
BRIDGWOOD: Now, the shame - and it's truly a shame - is we're going to tear all this out. And it's all going to go to the third floor.
ROSE: Fifty-five Water Street is moving its critical infrastructure up above the floodplain. Bridgwood says that will take years and cost the building's owner another $80 million.
BRIDGWOOD: That's a massive undertaking, a massive expenditure. But you want to be viable going forward and you want to attract the quality tenants that we have, these are things you just have to do.
ROSE: So if a flood like this happened again, how are you imagining that it will go?
BRIDGWOOD: I guess you would shut down for the day or two, you know, that the city might mandate. But we would expect that with everything we've done, we're ready to go.
ROSE: Fifty-five Water Street is a relatively modern building and its owner has deep pockets. Not all commercial buildings have the resources to do what it's doing. Regional solutions won't come cheap, either. It took a fight for Congress to approve $60 billion to rebuild after Sandy and prepare for future storms and that might have been the easy part.
Joel Rose, NPR News, New York. Transcript provided by NPR, Copyright NPR.