OLYMPIA, Wash., — As many as 108 people were listed as missing two days after a deadly mudslide north of Seattle hit dozens of homes and killed at least eight people, but many individuals still unaccounted for ultimately are expected to turn up safe, authorities said on Monday.
Still, emergency management officials expressed doubt that anyone else would be plucked alive from the muck and debris, and concern lingered about flooding from water backing up behind a crude dam of mud and rubble dumped into a river by Saturday’s slide.
“The situation is very grim,” said Travis Hots, Snohomish County District 21 Fire Chief. “We’re still holding out hope that we’re going to be able to find people that may still be alive. But keep in mind we haven’t found anybody alive on this pile since Saturday in the initial stages of our operation.”
The landslide was triggered after a rain-soaked hillside along State Route 530 near Oso, Wash., gave way on Saturday morning, washing away at least six homes in an area about 55 miles northeast of Seattle.
In all, at least 49 homes were believed to have been damaged by the slide, said John Pennington, director of the Snohomish County Department of Emergency Management. That figure was derived from the total number of land parcels — at least 112 — swept by the cascade of mud and known to have homes or other structures built on them.
The search for victims resumed early on Monday after treacherous quicksand forced rescue workers to suspend their efforts at dusk on Sunday. Some workers, mired in mud up to their armpits, had to be dragged to safety.
A spokesman for the Snohomish County Sheriff’s Office said eight bodies had been found by Sunday evening in the square-mile disaster zone of tangled debris, rocks, trees and mud. Another eight people were injured in the landslide.
On Sunday night, officials put the number of missing at 18 or more, but on Monday morning Pennington said agencies had collected reports — some specific and others vague — of 108 people who remained unaccounted for after the disaster.
“The number is, I think no question, going to decline dramatically. But it is a number that we want to just go ahead and disclose and say, ‘That’s what we’re working with,’” Pennington said.
The potential number of victims swallowed by the mudslide was higher on a Saturday, with many people at home, than it might have been on a weekday when more residents would have been at work or school, Pennington said. He noted that an unspecified number of construction workers were in the area at the time.
But authorities were hoping many of those reported as missing turn out to be survivors who were either double-counted or slow in alerting loved ones and local officials as to their whereabouts.
The slide in the foothills of the Cascade Mountains along the Stillaguamish River piled mud, boulders and rubble up to 15 feet deep in some places.
It blocked the flow of the river, backing up water behind a natural dam left in the stream’s channel that caused flooding of seven homes upstream of the slide, Pennington said.
“The bad news is that the water continues to rise and homes are inundated up to the eaves in many cases,” he said. “If there is a silver lining in that event … it is that it is a slow, methodical rise. You can see the danger.”
Authorities said as the volume and pressure of water behind the dam continued to build, there was a chance that additional downstream flooding and mud flows could be unleashed.
Water from the river was trickling through the side of the debris plug and creating a new stream channel, prompting authorities to post observation teams downstream to watch for signs of danger, state emergency management officials said.
Hots said Monday’s search for victims would incorporate the use of aircraft, teams with search dogs and special electronic equipment.
“Also, the Washington State Department of Transportation is going to have heavy equipment out there to clear mud out of the way so that we can continue to search those areas,” he said.
Washington Gov. Jay Inslee said the regional head of the Federal Emergency Management Agency issued a verbal declaration that would allow for immediate federal disaster assistance to deal with the aftermath of the slide.