Project overview
On Thursday, March 19, 2026, debris slides along northbound Interstate 5 near Bellingham brought thousands of cubic yards of boulders, trees and other debris down a slope and across nearby lanes of the freeway. Combined, the slides carved a debris field more than 250 feet wide and 100 feet tall between mileposts 248 and 249.
Boulders, some as big as buses and many others larger than a pickup truck, remained unstable and unsupported. Contractor crews working for the Washington State Department of Transportation began work Saturday, March 21, clearing debris and stabilizing the slope.
Crews worked 7 days a week and reopened the highway on Wednesday, April 15.
What to expect
Work has finished and northbound I-5 reopened April 15.
Northbound I-5 reopened on Wednesday, April 15, after a March 19 landslide.
On March 19, a landslide closed northbound I-5 near North Lake Samish south of Bellingham.
WSDOT geotechnical engineers began assessing slope stability Friday, March 20, and found areas of concern for more potential movement in the debris pile and higher above on the slope. Teams began developing and implementing plans to shore up and stabilize the slide area Saturday, March 21, so that cleanup work could safely begin. Contractor crews began limited rock and debris removal Sunday, March 22. This work is ongoing.
WSDOT will continue to work with contractor crews from Interwest Construction Inc. of Burlington to safely reopen this vital transportation corridor for people, freight and commerce between Seattle and Vancouver, B.C., as quickly as possible. Safety for work crews and travelers remains the top priority.
Due to the geology of the area, this location is known for slides. WSDOT maintenance crews routinely do hazard tree removal and vegetation management, and clear drains and culverts to help reduce chances of larger slides.
Concrete barrier was installed along the shoulder over this stretch of I-5 to catch smaller slides and prevent debris from reaching the roadway. During heavy rain events, such as the recent atmospheric rivers in 2025-26, soil saturation can create larger slides with more debris that can force highway closures.
