OSO, Wash. — A newly discovered “slow-moving hillside” near Oso prompted authorities Friday night to close State Route 530 and issue voluntary evacuation recommendations to residents in about 11 homes in the area.
It’s “a small and slow-moving slide,” said Snohomish County Sheriff’s Office spokeswoman Shari Ireton, adding that there were no injuries or property damage.
“What there is is a very slow-moving hillside,” Ireton told reporters at a media briefing at the Oso Firehouse. “Everything we’re doing tonight is just a precaution.”
She said geologist are calling this a “reactivation of small portion of a previous landslide.”
In March 2014, a large landslide near Oso killed 43 people and buried SR 530. This slow-moving hillside is about 2 miles west of the 2014 slide.
"Specifically, 10 homes along Whitman Road and one house to the south of SR 530 have been asked to evacuate," Ireton said in a news release. "Other area residents are being kept notified of developments through the night."
She said citizens reported seeing cracks along a private road that runs up the hillside south of SR 530. A geologist from the state Department of Natural Resources examined the hillside and roadway Friday and discovered several sites where "significant cracks in the slope indicated that the slope is moving and shared that information with county and state agencies," Ireton said.
The Washington Department of Transportation said it would be closing SR 530 between mile marker 35 and 36 at least overnight, until they can examine the hillside again in the morning light.