A new tool to track landslide threats in King County

SNOQUALMIE, Wash. – Record-setting October rainfall is just the start of what’s expected to be a wet winter.  With the wet weather comes the threat of landslides.

The most devastating of those slides came in 2014 when 43 people were killed in a landslide in Oso.  Mud and debris came rolling down on the rural Snohomish County town covering nearly a square mile.

The tragedy  sparked King County Department of Natural Resources geologists to do something they haven’t done in 25 years, re-map the landslide threat throughout their county.

Fall City resident Oster Gilbert said he's been watching an eroding hill on his land for two years. “It hasn’t threatened the county road yet, but it did close our doggone road to our property coming in the back way,” he added.

On Thursday night, Gilbert  joined others concerned about the landslide danger at a community meeting held by King County.

“We came to find out what the risk is, what should we be aware of, and what kind of things should we be prepared for,” said Fall City resident Tacy Hindle.

Hindle brought her questions to geologist John Bethel.

“I think everybody thinks about the tragedy that happened in Oso,” said geologist John Bethel.

With 49 homes destroyed and 43 people killed in Oso two years ago, how do you know if your property is at risk?  You can now check by using iMap King County.  Once on the site, hit the layers button and click on landslides.  Then, type in your address.

It’s a new tool to check the threat, even if your home isn’t near an outlined area.

“A landslide occurs where it wasn’t typically anticipated or where it didn’t happen on a repeated basis,” said Bethel.

So make sure your landscaping is in order.

“Healthy, robust, native vegetation growing on slopes is quite helpful,” said Bethel. “The slope becoming saturated and often that happens as a result of storm water being directed in a concentrated place on the slope.”

But with the unpredictable nature of landslides, some still wonder…

“Is this slide going to keep creeping down the side of the hill?” asked Gilbert.

Bethel says if you have a specific worry about something on your land or nearby, contact a consultant.