PORTLAND, Ore. — A house in an affluent southwestern Portland neighborhood broke free of its foundation Wednesday, slid at least 100 feet down a hillside and slammed into two other houses.
A woman in the house, Kathleen Hendrickson, was rescued, neighbors said.
The house that slid down the hill was wrecked. One of the houses it hit was bumped off its foundation.
A geologist said other houses in the neighborhood in Portland’s West Hills may be in jeopardy.
Neighbor Greg Sherwood told KGW-TV he heard what he thought was garbage being taken out before dawn, but he looked across the street to see the house starting to fall over backward.
After calling 911, he ran across the street, where he and a neighbor lay where the slope gave way and extended a ladder to the woman.
He said she was atop the structure, which had turned so that one side faced up.
“We were able to get the ladder down to her and pull her up out of the hole there,” he said. “Then a couple of minutes later, the whole house gave way down the hill.”
A state landslide expert said he mapped as many as 700 slides in the Portland area after a stormy winter in 1996-97.
“Many houses were damaged, but I don’t remember any cutting loose and sliding down the slope,” said Bill Burns, an engineering geologist for the Oregon Department of Geology and Mineral Industries.
Burns said landslides are products of steep, unstable slopes loosened by moisture.
The west hills of Portland are underlain by loess, windblown deposits known for instability, he said. And the house was at the steeper part of a slope Burns estimated at 20 degrees to 40 degrees.
How the hillside got wet enough to give way, though, is a question, Burns said.
The Portland area got rain in early October, but it’s just the beginning of the city’s rainy season, Burns said. So, investigators might look for broken water lines or springs.