Massive landslide more than a decade in the making
WHIDBEY ISLAND, Wash. — State and Island County geologists said Thursday night they believe the hillside where the massive landslide occurred south of Coupeville began to give away more than a decade ago, in 2002, and that time, water and gravity led to the inevitable event.
“What happens is you’ve got this heavier, denser, dry level on top of the layer that gets wet with the clay layer and that, as that clay gets lubricated, that’s what lets the block slide,” Island County engineer Bill Oakes said.
The experts said they believe the worst of the slide has passed, but the ground is still settling and there is still some minor slide activity or sloughing of dirt from the hillside.
“Oh, it is very unpredictable,” Oakes said. “We have very active coastal geology in Island County and it’s very difficult to predict when and where an individual slide is going to occur.”
Experts said 3.5 million square feet of land dropped away Wednesday morning, along with a lot of trees.
Late Thursday night, residents packed a community meeting, concerned about what will happen next.
Five homes are deemed still at risk. One home is red tagged, which means no one can go inside; four others have been yellow tagged, which means people can get inside but only to retrieve belongings.
As for Driftwood Way, which ran along the lower portion of the cliff and which was destroyed by the slide and left impassible, engineers are already studying the potential to replace it, but that won’t happen anytime soon.
“It would be basically rebuilding a road across a debris field and we don’t typically look at that but the other alternatives are not there in this case. We would typically not do that,” Oakes said.
In the short term, efforts are under way to turn the foot path into a temporary single-lane road. That could take two weeks and, even then, navigating it won’t be easy.
“It is a steep approach. I mean if you’ve been down there, it will be a steep road and it won’t be paved in two weeks. It will be a gravel surface so,” Oakes said.
Until Thursday, resident Morgan Bell’s attempts to get to her house on the bottom side of the slide was not easy — a quarter-mile hike along a muddy, switchback single-track trail.
But it was a trek she was more than ready to take.
“I think the house itself is going to be safe, but I’m concerned that if they can’t rebuild the road, or it’s too expensive to rebuild the road, that they’ll condemn the houses. And my car and everything I own is down there,” Bell said.