STEVE INSKEEP, HOST:
Let's talk next about a natural disaster. The many cities hit by hurricane Sandy included Hoboken, New Jersey. That city's mayor is ready to build walls to keep the water out next time, but that's a challenging proposition and the subject of today's business bottom line. Here's NPR's Joel Rose.
JOEL ROSE, BYLINE: Hoboken used to be an island, surrounded by the Hudson River on one side and tidal marshes on the other. By the 20th century, those wetlands were paved and developed. But after Hurricane Sandy, Hoboken was an island again.
MAYOR DAWN ZIMMER: The water came in at the south end of Hoboken, and then it came in at the north end of Hoboken and filled up the back end, and then started coming forward.
ROSE: Mayor Dawn Zimmer says more than half of Hoboken flooded during Sandy. But that's where the similarities with the Jersey Shore end. Hoboken is dense and urban with block after block of brownstone townhouses, tenements and high-rise apartment buildings. And Zimmer says the government's usual response to flooding - which is designed for coastal communities - won't work here.
ZIMMER: No, we cannot raise our homes up on pilings, and we need to have a different approach. Instead of having each person try to do their own flood mitigation, that we should be trying to protect the entire city.
ROSE: To do that, Zimmer is proposing a, quote, "universal solution" to protect all of Hoboken. She's calling for a system of emergency micro-generators that could keep the lights on in high-rise buildings, along with additional parks and green roofs to capture more water. But her most dramatic proposal is a system of floodwalls and retractable gates intended to protect Hoboken from a major storm surge like Sandy's.
ZIMMER: There is some criticism, like how can you put up walls around the city? But the reality is, you know, I'd rather have walls around the city to protect it than to have a city that's destroyed.
ROSE: But those floodwalls have risks of their own.
PHILIP ORTON: There's a big danger with any type of wall system. There's the New Orleans effect.
ROSE: Philip Orton is an oceanographer at the Steven's Institute of Technology in Hoboken, where he studies storm surge and sea level rise. The school sits on the highest point in town, on the waterfront facing Manhattan. Orton says a system of walls and retractable gates could work for Hoboken, but they would have to be tall enough and strong enough to protect every part of the city.
ORTON: The lowest-lying areas of Hoboken, you need probably a 10 or 15-foot-high wall. And you really don't want to under-build it, because if it gets overtopped, then it becomes a 10-foot-high pool of water behind it that's trapped. And that can be more deadly than just the common flooding problem that you might have.
ROSE: Which is roughly what happened in New Orleans after Hurricane Katrina. Hoboken isn't huge - just a few square miles - but to build floodwalls that high would be expensive. And critics say it could wind up hurting Hoboken's neighbors to the north and south. Paul Gallay is the Hudson riverkeeper.
PAUL GALLAY: Trying to wall off storm surges in densely populated areas like Hoboken is not the way to go. In the short run, it pushes water off onto surrounding communities, like Weehawken, Jersey City and, of course, the river to Manhattan. And in the long run, you end up overwhelmed by ever-rising waters.
ROSE: Gallay does like some other elements of Mayor Dawn Zimmer's plan, especially the part about more parks and green roofs. But Zimmer says those ideas alone won't solve Hoboken's flood problems. She's hoping to persuade state and federal authorities to help fund her most ambitious proposals.
ZIMMER: We've got a city with fantastic character, and we don't want to destroy that character. And most importantly, I mean, what we're talking about is the future of Hoboken and the future of, you know, the urban landscape.
ROSE: Mayor Zimmer wants Hoboken to be a test case. If these ideas work here, maybe they can help other low-lying coastal cities like Boston and Philadelphia, too. Joel Rose, NPR News, New York. Transcript provided by NPR, Copyright NPR.
