By Laura Zuckerman
April 19 (Reuters) - A slow-moving landslide claimed a house in Jackson, Wyoming as crews scrambled to prevent a water main from rupturing and flooding the affluent resort town with two million gallons of water, a city manager said Saturday.
The landslide, which has prompted the evacuations of homes, apartment buildings and businesses, has picked up speed, doubling its acceleration since early April and speeding significantly in recent days, the town of Jackson said at the weekend.
The East Gros Ventre Butte, about one mile (1.6 km) from downtown Jackson, a popular international ski destination and gateway to Grand Teton and Yellowstone national parks, was slumping at a rate of as much as a foot a day from the previous rate of about four inches, authorities said.
A house at the highest point of a residential development on the hill's east face was torn in two late Friday as the ground beneath it dropped an estimated 20 feet, said Roxanne Robinson, the town's assistant manager.
"The house," the first destroyed by the slide, "was pulled apart. It's completely separated," Robinson said.
Utility workers were planning to try to re-route a section of a city water main threatened by the slide, which could spill millions of gallons of water onto the highway that serves as Jackson's primary north-south artery.
Robinson said that pavement has buckled as much as seven feet near a two-level parking facility which bears signs of structural stress.
While more than 50 residents on the butte have evacuated, an undetermined number has refused to leave, she said.
According to geologists, the butte could have become unstable because of land development, rains and snow melt.
(Editing by Chris Michaud)