MELISSA BLOCK, host:
For cities and towns across the U.S., this spring has brought a series of fast-moving natural disasters, from tornadoes to flash floods.
In northern New York and Vermont, a disaster has developed slowly. Weeks of torrential rains have overwhelmed Lake Champlain, flooding hundreds of miles of coastline. Now, in the mountain village of Keene Valley, New York, all that water has triggered a massive landslide that is destroying a neighborhood in slow motion. North Country Public Radio's Brian Mann reports.
BRIAN MANN: Town Supervisor Bill Ferebee walks along a gravel road, stepping over big fissures.
BILL FEREBEE (Keene Valley Town Supervisor): This all - this area has just dropped.
MANN: He's here to inspect one of the dozen houses perched on Little Porter Mountain. It looks like someone grabbed the entire structure and gave it a fierce twist.
Mr. FEREBEE: You can see here how the house has lifted. Now, this has lifted in the last three days so - which means that house is tipping forward.
MANN: Nearby, a stream surges with water. New York's Adirondack Mountains saw heavy snow last winter. The spring melt, combined with record-setting rain, has literally broken loose the entire flank of the mountain.
New York state geologist Andrew Kozlowski says hundreds of thousands of tons of rock and earth have been destabilized.
Mr. ANDREW KOZLOWSKI (Geologist): The area that's moving, that's impacted, is 82 acres. Eighty-two acres of land mass on the side of the mountain is actually, physically moving. It's the largest landslide in the state's history.
MANN: More homes and businesses sit at the bottom of the slide. It's oozing slowly, Kozlowski says, no faster than three feet per day. But it's so big that scientists have been arriving from all over the country to study it.
Mr. KOZLOWSKI: We still really have very little, in terms of subsurface information, to understand the depth and the actual extent in the subsurface of how wide this event is.
MANN: Gathering good data has been tricky, in part because the terrain is incredibly treacherous, with trees toppling and boulders kicking loose.
Mr. KOZLOWSKI: It definitely gets your attention when you hear the trunks cracking en masse. The boulders are sort of - you hear a tumbling or a thumping sound, and you'll sort of look up and catch a glimpse as they're sort of moving down through the forest. And you hear them hitting tree trunks because they're moving down-slope. And so you just try to get between a tree and where you think they're coming.
(Soundbite of vehicle ignition)
MANN: Just down the road, a truck is pulling away from another threatened home, salvaging furniture owned by Charity Marlatt. Her house is perched at the very top of the slide, its foundation half-exposed.
Ms. CHARITY MARLATT: If I weren't so emotionally involved, if my heart weren't so broken right now, this would be a fascinating situation because I've learned more about geology than I probably would care to.
MANN: Scientists say they haven't got a clue when Little Porter Mountain will stop moving, or how much of the neighborhood will be swept away, before this slow-motion disaster is over.
For NPR News, I'm Brian Mann in New York's Adirondack Mountains.