Watch out Sumas Mountain. The Washington state Department of Ecology and Whatcom County Public Works are teaming up to clean up your mess.

For decades, a slow-moving landslide on the west side of Sumas Mountain near Everson, Whatcom County, has dumped naturally occurring asbestos and metals into Swift Creek. And for decades, people have dredged the creek to limit downstream flooding.

Officials estimate the landside to be a mile long and 1/4 mile wide. Each year it deposits a significant amount of sediment into the creek — about the size of the Whatcom County Courthouse.

It can be dangerous during the summer when the sediment dries and asbestos can be inhaled, according to the state ecology department.

Well, this year, all that comes to an stop — or more accurately, a slow.

Whatcom County will soon begin construction as part of the Swift Creek Action Plan, which will ultimately slow the Swift Creek enough so that sediment settles out of the water in the creek’s upper reaches.


From there, the county will collect, store and cover the asbestos-containing sediment in long-term repositories to contain asbestos dust. Swift Creek will then slowly navigate a new channel with new sediment traps, and join the Sumas River with less sediment.

Some construction is expected to last through 2027.

The action plan was set into motion late 2019 when the Whatcom County Council signed a consent decree.

This is how the Washington state Department of Ecology characterized the event: “Unfortunately, a photo couldn’t quite capture the satisfaction in the room, but you can see a few smiles accompanying the pens.”