MELISSA BLOCK, HOST:
Hurricane Sandy washed away houses, boats and boardwalks. It also washed away dunes, what served as protective barriers between coastal communities and the ocean. Now, scientists are investigating how drastically the storm redrew the coastline. NPR's Adam Cole has that story.
ADAM COLE, BYLINE: When the residents of Mantoloking, New Jersey, heard that Sandy was coming, almost everyone left town, but Edwin C. O'Malley and his father, Edwin J. O'Malley Jr., stayed put. They tied a boat to the porch of their 130-year-old house and then watched the ocean break over the dunes and flood the streets.
EDWIN C. O'MALLEY: And overnight that night, lying in bed, I could actually hear waves hitting the side of the house, which obviously made it more difficult to get to sleep.
COLE: The ocean entered the O'Malleys' living room, rose to the height of the couch cushions and then retreated. Other homes weren't so lucky.
O'MALLEY: When the weather finally cleared, looking out of the east side of the house towards the ocean, where we would normally see houses or trees blocking our view, we could see breaking ocean waves. At that point, we knew houses were gone.
COLE: And Sandy didn't just destroy several of Mantoloking's multimillion-dollar beachside houses, it reshaped the beach itself.
O'MALLEY: Those dunes were 100 percent gone. Some of that sand, of course, got sucked out to the ocean, but a lot of it got pushed into town, in between houses, onto the streets and all that. So there were sand dunes on the streets in some places that were a couple of feet thick. And my father and I walked the dogs through the center of town over huge piles of sand right in front of the post office and police station.
COLE: It was a bizarre scene, one repeated all along the New York and New Jersey coast.
CHERYL HAPKE: For my career, this was the most coastal change that I've seen from a single event.
COLE: Cheryl Hapke is a scientist with the United States Geological Survey. She's part of team trying to measure what Sandy did to the coast. Before and after the storm, team members traveled from the outer banks of North Carolina up to Long Island in a low-flying plane, collecting photos and topographical data. The post-Sandy images are striking. They show whole islands sliced into pieces and more.
HAPKE: Just huge boat yards that had been, you know, ripped to shreds.
COLE: They saw the remains of an amusement park.
HAPKE: You know, the giant rollercoaster just sitting in the surf zone what was truly amazing.
COLE: And everywhere, there was a new coastline. The ocean had moved inland, pushing the dunes in front of it. It will take a few weeks to figure out just how much sand was moved, but the USGS has some initial measurements from Fire Island, New York. Two days before Sandy hit, Hapke rushed out there to measure the dunes, and once the storm was over, she returned to the island by boat with a few rangers from the National Park Service. At the height of the storm, nearly half of Fire Island was underwater. Some of the dunes lost 10 feet of elevation, and on average, the shoreline retreated 72 feet.
HAPKE: Which is huge. I mean, that's, you know, if your house is there, it's gone.
COLE: Hapke says that beaches further south have probably seen even bigger changes, but she adds that the healing process has already started. The dunes are doing what they always do. The sand that was pushed inland will reform into dunes in that new spot, but Hapke says that can cause problems. People don't want dunes in their streets. They want to rebuild the beach back where it once was.
HAPKE: But basically, it doesn't want to be there. It wants to move as sea level rises. So the more we put it back, the more likely it is to experience this kind of impact in another severe storm.
COLE: And that raises the question that's sure to be debated as the East Coast recovers from Sandy: Should everything be rebuilt just the way it was before? Adam Cole, NPR News.