In the decade since the Oso landslide, technicians have meticulously mapped the state of Washington, scanning thousands of square miles of terrain, precise nearly to the inch, part of efforts to forestall another tragedy like the one that killed 43 people when the hillside above Steelhead Haven collapsed 10 years ago this week.
The maps, created using planes that fly over the state taking laser measurements of the ground below, help geologists analyze where landslides have happened, whether a year ago, or 10,000 years ago. Past landslides are the best predictor of future landslides.
Geologists with the state Department of Natural Resources have mapped 34,683 slides over the past decade.
And yet …
While they now have laser-created lidar maps of nearly the entire state, they’ve pinpointed past landslides in only 14% of it. And they haven’t taken the next step, recommended by a number of outside experts, of plugging that data into models to try to map the potential hazard zones of future landslides, and then highlighting where a landslide would have the gravest consequences.