Washington mudslide: death toll to rise dramatically in next two days, say authorities

The announcement comes as the likelihood that any more survivors will be found becomes increasingly unlikely

A rescue worker looks over the debris pile from the mudslide in Oso, Washington March 27, 2014. (REUTERS/Mark Mulligan/Pool )

The death toll following the mudslide in Washington last Saturday is expected to rise dramatically in the next two days, according to state authorities.

16 bodies have been recovered and 90 people are still missing following the mudslide that occurred 55 miles northeast of Seattle.

On Wednesday, nine more people had been found but not yet been retrieved by search crews. However, Snohomish County District 21 Fire Chief Travis Hots said on Thursday that officials are not going to count additional recovered victims until the medical examiner's office had caught up with the recovery effort.

“In the next 24 to 48 hours, as the medical examiner catches up with their work, you're going to see these numbers increase substantially,” Hots said.

As the search entered its sixth day on Thursday, hope of discovering survivors has faded, but Hots said his crews will exhaust all options in the hope that somebody is alive amid the devastation.

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“My heart is telling me I'm not giving up yet,” he said. “If we find just one more person alive, it's all worth it to me.”

Meanwhile, many people who were thought to be missing in the incident have been found safe and alive.

But rescuers are far from completing their task of bringing closure to the relatives and friends of those who have not been found, by scouring the debris field that covers around a square mile of ground (2.5 square km) and is 30 to 40 feet (9 to 12 meters) deep in places.

Their job is only made tougher by the quicksand-like muck, rain-slickened mud and ice which cover the surface of the area. The terrain makes it treacherous or impossible to bring in heavy equipment.

To make matters worse, the pile is laced with other hazards that include fallen trees, propane and septic tanks, twisted vehicles and countless shards of shattered homes.

Seismic signals showed there were two major slides about four minutes apart during Saturday's disaster and afterward smaller slides continued for days, University of Washington researchers said.

The landslide moved with surprising speed, said Ralph Haugerud, a USGS research geologist at the University of Washington.

“Not very many move this fast,” he said Thursday. Typical landslides in the Nooksack Valley “crept down the hill.”

The vibration of falling can cause a landslide to turn into a debris flow that moves like water.

“My hunch is the slide may have dropped farther than many, and as it did it liquefied,” Haugerud said.

The study of seismic signals showed no earthquake triggered the slide, said Kate Allstadt, a university researcher.

Landslides are harder to study than earthquakes because the signals are less clear and don't travel as far, said Allstadt, who used seismology tools to research landslides for her doctorate.