In the days since the devastating landslide swept through a stretch of northwest Washington state, all the news has been bad. As hundreds of workers spent a fifth day digging through debris and wreckage, the death toll had increased to at least 16 and was expected to keep rising; worse, no survivors had been found since Saturday, the day the landslide hit.

More than 200 rescue workers continued to search the area, trying to find survivors and locate bodies, a job complicated by the nature of the landslide site, which has been compared to quicksand by officials. The slide area spans a square mile, and it’s at least 15 feet deep in some spots, according to the county. Rescue workers have to search a sea of mud and debris, navigating the twisted wreckage of cars, piles of wood, debris from homes, spilled gasoline and septic material that are all mixed together in the search area.

“Our rescuers were sinking down to their thighs in the soft silt,” Bill Quistorf, the chief helicopter pilot for the Snohomish County Sheriff’s Office, said during a news conference on Wednesday. “It was very difficult.”

These workers are digging through the carnage with their hands and shovels, searching the area from helicopters and with infrared scanners, trying to focus on areas where they think there could be people. Search dogs have been the most effective way of finding bodies, helping them figure out the areas to look, Travis Hots, the Snohomish County District 21 fire chief, said in a news conference.

Rain arrived on Tuesday and was expected to continue for days, which made for another challenge, Hots said. The environment itself has also posed dangers and challenges. Rescue crews had been pulled back for a few hours on Monday due to fears that additional slides were possible, while authorities are also keeping an eye on the Stillaguamish River to watch for flood hazards.

“It’s just amazing the magnitude and the force that this slide has created and what it has done,” Hots said.

This slide in particular is different because of the size, said Lynn Highland, a geographer with the U.S. Geological Survey who has studied landslides for 30 years.

“Usually landslides when they fall, they’re kind of confined,” she said in a phone interview Wednesday. “This one had such a volume of material that it ran out on one side of the river, crossed it, dammed it and came out on the other side of the river.”

Authorities are keeping an eye on the Stillaguamish River, because a blockage created by the landslide and the rain that followed raised the possibility of a flood hazard.

The field of debris also offers potential for injuries to workers. A volunteer rescue worker was taken to the hospital after suffering minor injuries working in the landslide area on Tuesday; a helicopter kicked up a small bit of debris that hit him in the head.

“It was pretty mind-numbing,” Randy Fay, one of the rescue workers, said of the devastation during a Wednesday news conference.

So for these rescue workers struggling to look for signs of life, all they can do is try to cling to what victories they could. Fay talked about helping to save survivors in the hours after the landslide, describing some of the efforts to pull people from the mud and, in one woman’s case, “what was left of her roof.”

But he began to get choked up when describing the rescue of a young boy, explaining that as a grandfather, he couldn’t help but think of his own grandchild. Working with injured children is the hardest thing, he said, because you think about your own loved ones.

“The good news, the silver lining, is mom and kid are back together, so that’s what you hang onto,” he said during an emotional appearance.

The death toll remained 16 by Wednesday night, though authorities believe they had found another eight bodies, John Pennington, director of emergency for the county, said in a briefing. Those bodies have not been recovered or brought to a medical examiner yet, so they are not confirmed, he said.

The list of people believed to be missing or unaccounted for had dropped to 90 on Wednesday night, down from the 176 number that had been in place for two days, Pennington said in a briefing Wednesday night. He said that 140 of the 176 names that had been listed as missing are safe and well. But there are another nearly three dozen other people whose status remains unknown.

“It’s definitively 90 people we can identify as unaccounted for or missing,” he said. “It’s 35 we just don’t know.”

As the search efforts continue, many have been asking whether the slide could have been foreseen. Pennington said earlier this week that the slide was “completely unforeseen” and “came out of nowhere.” Seattle Times) warned a full 15 years before this slide that there was “potential for a large catastrophic failure” in the area. There was also a landslide in 2006. And a 2010 county report (also flagged by the Seattle Times) dedicated a chapter to landslides, explicitly warning that heavy rains during the winter months saturate the soil and lead to slides; the county and the U.S. Geological Survey have said this is believed to be the cause of this fatal slide.

Pennington, asked about the earlier warnings during the Wednesday morning briefing, said that he and others want to understand why it happened. He said people knew the area was prone to landslides.

“We did everything that we could have done and the community did feel safe,” Pennington said. “We did what we could do. Sometimes large slides happen.”

This post will be updated as new information becomes available. Latest update: 9:26 p.m.