By Dan Catchpole, Noah Haglund and Scott North Herald Writers
OSO — Before the hillside wiped out Steelhead Drive on Saturday, the people who lived there worried more about flooding from the Stillaguamish River.
They weren’t alone.
They worked with Snohomish County, the Army Corps of Engineers and other agencies to keep the river from gnawing away at their land.
They knew slides were possible – like a big one in 1967, and another in 2006 that blocked the Stilly — but they never imagined that the slope rising steeply above the river’s north bank could bury a neighborhood.
“We had one eight years ago. How could it happen again?” asked Ruth Hargrave of Kirkland, who along with her husband, Davis, owned a cabin that was swept away.
While experts raised concerns about the potential for catastrophic consequences of the river eating away at the toe of the earlier slides, the focus for Snohomish County officials was on flooding.
“We never, ever expected or anticipated a slide of this size would occur,” Steve Thomsen, the county’s public works director, said Tuesday.
“It’s epic, it’s incredibly large. I’ve never seen anything equivalent to it in the 30 years I’ve been engineering,” he said.
Saturday’s slide involved an area about 600 feet high by 1,500 feet across. It left a square-mile debris field up to 50 feet deep in places.
The 2006 slide didn’t reach any homes. Within days, 17 property owners had signed paperwork granting the county permission to perform emergency work on the south river bank.
Some of those people now are unaccounted for, or had homes that were obliterated.
“We were just trying to stabilize the river so we could save the community from additional flooding,” Thomsen said. “That was our main goal.”
That focus remained, in spite of a 2000 U.S. Army Corps of Engineers study that warned lives would be at risk if the hillside came crashing down.
The study said one option would be trying to harden the river bank at the bottom of the hill to resist erosion. It also explored buying out the property owners to get them out of harm’s way. The author, however, discounted that notion, since it was unlikely they would want to sell.
Among those missing is Thom Satterlee, who had spent years telling county officials they had no authority over him or what he did with his land. The three-bedroom rambler he shared with his wife, Marlese, was wiped out when the slide buried Steelhead Drive. The couple reportedly haven’t been seen since.
Thom Satterlee was no fan of the state’s 1990 Growth Management Act, which among other things aims to keep communities from taking root in environmentally sensitive areas. He challenged how Snohomish County officials attempted to implement the law. Starting in 1993, Satterlee was among the most vocal supporters of a movement to carve a new government he called Freedom County from a 1,000-square-mile area in Snohomish County’s north end.
State and federal courts consistently ruled that Freedom County did not exist, but that didn’t stop Freedom County backers from naming as sheriff a retired FBI agent who called himself Fnu Lnu.
During the Freedom County battles, Satterlee listed his home as an isolated parcel off Whitehorse Drive, farther up the North Fork Stillaguamish River. Property records indicate the Satterlees acquired their Steelhead Drive property about five years ago. Their home was built there in 1991.
Though the area has been described as akin to a modern housing development, construction along Steelhead Drive has played out over the past 50 years.
Some homes in the area near Saturday’s slide date back to the 1920s, according to county property records. They started out as mountain cabins and weekend getaways along a river that fishermen love.
On Saturday morning, there were a total of 22 homes there. A handful of the buildings went up in the 1960s. They were followed by a few more there, and along Highway 530, in the 1970s. Most involved modest, single-family homes and vacation cabins, including a few pre-fab buildings.
The most-intense activity came in 2005 and 2006, when seven new single-family homes were built. A few years later, three more were approved on the south side of the highway.
The last home added to the area came in 2012, when a manufactured home was installed along Steelhead Drive.
The hillside that gave way Saturday was one of many areas mapped by the county in 2004 as a potential landslide hazard. In Snohomish County’s 2005 natural hazards mitigation plan, the county estimated that areas vulnerable to landslides contained 28,500 residents and 11,500 structures, many of them along the county’s western coastal bluffs.
Several government reports prior to the 2006 slide highlighted the danger in Oso.
“The development of the floodplain has encroached on the river’s natural channel migration and places current residents at risk,” Tracy Drury wrote in a 2000 study for the Army Corps of Engineers.
Based on the available data and prior events, the hillside “poses a significant risk to human lives and private property,” he said.
Drury recommended possible actions, including hardening the riverbank at the bottom of the hill, buying out properties potentially at risk and pushing the river a few hundred feet to the south, which happened anyway after the 2006 landslide.
It wasn’t immediately clear how aware county officials were of Drury’s work and other studies, but Ruth Hargrave said she was unaware of the extent of slide concerns.
“I never heard of that, and I can say I never heard anyone talk about it,” she said. “That’s pretty big information that we should have known.”
The Hargraves attended two community information meetings after the 2006 slide and said they never heard about the potential for a catastrophic slide.
“It’s a slide-prone area. Everybody knows that,” Davis Hargrave said. “ … You don’t need to be an engineer to look at that (hill) and know there’s unstable soil.”
They were drawn to the tranquil setting near the river as a weekend getaway. Their neighbors were mostly full-time residents, many of whom became dear friends. The couple often attended community get-togethers at the fire station just down the highway.
Like many people, they are still absorbing the loss of friends and neighbors.
Dan Catchpole, 425-339-3454, firstname.lastname@example.org