The accident, which involved a logging truck losing its load, happened about 9:30 a.m. State troopers are on scene.
WSDOT officials said they don’t know when the highway will reopen.
UPDATE as of 11:11 a.m.: The collision is still blocking the right lane and on-ramp from southbound SR 167.
Troopers, a WSDOT Incident Response Team and tow trucks are working to clear the scene.
UPDATE as of 12:57 p.m.: All lanes are now open.