STEVE INSKEEP, HOST:
Some of America's coastal communities fear losing some of their land and also some of their history - history that drives tourism and their economies, places from New Orleans to New England's iconic fishing villages. Stephanie Leydon reports from member station WGBH.
STEPHANIE LEYDON, BYLINE: Portsmouth, N.H., is postcard-perfect New England - a compact city of red brick and cobblestones built - for good reason - on a river's edge.
RODNEY ROWLAND: The settlers who came here had to settle on the coast. They needed water for transportation; they needed water for a food source. And so the oldest parts of our country are right on the water.
LEYDON: For Rodney Rowland, managing water is now a priority. He's in charge of maintaining the three dozen historic homes that make up Strawbery Banke Museum.
How old is this house, Rodney?
ROWLAND: Shapley-Drisco House is 1795.
LEYDON: This 200-year-old house has withstood two centuries of storms. But in the last decade, tides from the river just across the street have reached unprecedented levels.
Oh, it's tight quarters down here.
ROWLAND: (Laughter) Very.
LEYDON: Water now routinely floods the basement.
ROWLAND: We've measured from 16 inches of saltwater in this basement during periods of astronomical high tide to 26 inches of saltwater in this basement during a nor'easter.
LEYDON: That saltwater has eaten away at mortar around the chimney bases and rotted the wood beams that support the house.
That rot eventually means what for the house?
ROWLAND: It'll fall down. One of the timbers supporting the first floor let go due to rot and the entire floor dropped a couple of inches.
LEYDON: The region's history is on the line, but so is its bottom line. More than 100,000 people a year visit Strawbery Banke Museum. Saving it is key to saving the region's tourism economy. Portsmouth, N.H., is not alone. Coastal communities nationwide are grappling with the impact of increasingly heavy and frequent storms. And it's not just old buildings that are threatened. Rising seas are also destroying less obvious pieces of history.
MEGHAN HOWEY: We're here at the mouth of the Oyster River where it enters the Great Bay. If you look that way, you're headed pretty much straight to Portsmouth. And down...
LEYDON: Meghan Howey, a University of New Hampshire anthropological archaeologist, is leading me through the woods to the site of her latest dig - the remnants of a house built by the British in the 1600s.
I don't see a house here.
HOWEY: Yeah, that's the point. The house is long gone, but the foundational kind of mound and debris remains are here.
LEYDON: I follow her to the edge of an embankment and a sweeping view of the river. This location, she says, allowed early settlers to keep an eye out for enemies. But instead of an advantage, in recent years, the river has become a liability - eroding the embankment where the house once stood.
HOWEY: I can show from aerial photo analysis that it went out about 20 feet further less than 20 years ago. There's been that much erosion through storm surges primarily.
LEYDON: Rising water is washing away the last traces of the 17th-century home, sending the rocks that once formed its foundation back toward the river. Howey's research shows over the next century, storm surges threaten to wipe out 14% of historic sites along New Hampshire's seacoast.
HOWEY: And if the erosion keeps happening in the way it is, that's just going to be more and more history that's going to wash away before we even get to it.
LEYDON: It's not just an academic loss. Authentic history, she says, is a selling point for tourist destinations worldwide. And in coastal communities, it raises an important question - how best to preserve that past given the threat of future storms?
For NPR News, I'm Stephanie Leydon in Portsmouth, N.H.
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