Was Oso mudslide nature’s mystery or man’s mistake?

OSO — Nearly a year after the worst disaster in modern Snohomish County history, a legal battle continues to take shape over whether somebody should be held responsible.

Was the March 22, 2014, mudslide near Oso a tragic display of natural forces reshaping the land, or a calamity caused by human hands?

Did local governments have a duty to discourage people from making their homes along the banks of the North Fork Stillaguamish River beneath a slide-prone hill, a place where 43 people later lost their lives?

So far, four lawsuits have been brought in King County Superior Court by those who lost family and homes. Three of the cases, representing the bulk of the plaintiffs, have been consolidated for a single trial, now scheduled for October.

Defendants include Snohomish County, the state of Washington and Grandy Lake Forest Associates, LLC. The Skagit County-based timber company not only owned part of the hill that fell but also engaged in limited logging there years before.

Seattle attorneys Corrie Yackulic and John Phillips represent the largest bloc of families. Yackulic can’t say much about what her team has learned. By March 23, she and the other plaintiffs’ attorneys are expected to tell the court which experts they’ll be relying on to help make their case.

“We are working really hard,” Yackulic said.

So far, there have been 20 depositions. Another 50 are expected, said Jason Cummings, the county’s chief civil deputy prosecutor.

Attorneys also have gathered up and pored over hundreds of thousands of pages of public records, scientific reports and other documents.

“This isn’t a sprint. This is a marathon,” Cummings said.

While the litigation promises to focus heavily on earth sciences, land-use policy and forest practices, attorneys are mindful that people are at the core of the case.

“Our hearts go out to the families of all those affected by the slide,” Cummings said.

The legal arguments

The theories advanced by the plaintiffs in court pleadings are nuanced and complex. Still, they could be summarized something like this: Logging on the bench above the hillside allegedly allowed unnatural amounts of water to seep into the slope, lubricating already slippery soils. Gravity and the gnawing river below worked to repeatedly bring down blocks of earth. Over decades, state and county officials responded with ineffective measures. They allowed more trees to be cut, more homes to be built nearby and put the greatest emphasis on fighting flooding and protecting fish. Those who lived nearby were reassured they were safe, the plaintiffs allege, particularly when work was done to control erosion after a large slide in 2006 that blocked the river.

The defendants’ legal responses could be boiled down this way: the slide was an act of of God or nature; officials acted in good faith and made decisions protected by law, particularly in response to flood risks; if mistakes were made, not all the defendants are equally to blame; and the plaintiffs’ own actions may have contributed to the harm.

This “case is being litigated as if it were — as one would expect it to be — a very large case,” attorney Elaine Spencer of Seattle said in court papers filed on behalf of her client, Grandy Lake.

The logging company is challenging allegations that it is partly responsible for the tragedy. It also maintains those claims should not be heard by a King County jury, but by people from Skagit or Snohomish counties, where it does business. That argument so far has found no traction with the King County judge. Grandy Lake has asked the state Court of Appeals to review the pre-trial ruling.

Pleadings demonstrate little agreement among the lawyers on the significance and meaning of scientific reports prepared prior to the slide. Plaintiffs maintain the reports were filled with red flags. Defendants counter that people have cherry picked information and presented it out of context to butress claims not supported by science.

Much remains unknown.

A January report released by a team of U.S. Geological Survey scientists determined that months of near-record rainfall played a key role in the hill’s collapse. The super soggy soil also added to the slide’s destructive power. The report made clear that more work needs to be done to understand how water entered and moved around the bluff.

Likewise, given the evidence of past slides near Oso, dating back eons, renewed activity should come as no surprise from a “geological perspective,” the report’s authors found. But they made clear that’s different from having the data necessary to forecast the slide’s timing and the mobility of the 10.8 million cubic yards of debris it unleashed.

To do so “would have required knowledge that was unavailable,” the report found.

Scott North: 425-339-3431; north@heraldnet.com. Twitter: @snorthnews

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