The key northbound I-5 highway near Bellingham, Washington, has been closed for more than a week, and authorities still cannot provide even an approximate reopening date. The closure was caused by a large slope failure during the night of March 19, when rocks, trees and other debris completely blocked all lanes between Padden and Samish lakes. The volume of material that slid onto the road is estimated at 2,000–3,000 cubic yards, comparable to the volume of an Olympic swimming pool.
The main difficulty preventing a quick reopening is the extreme instability of the slope itself. As the state Department of Transportation explained, this is not a standard debris cleanup. Workers must carry out careful and slow engineering stabilization: first secure the top of the slope, then, moving downward, drill and install steel pins to anchor it. Because the work is methodical and hazardous, there is no specific timeline for restoring traffic.
While work continues, traffic is being detoured via alternate routes — Highway 9 or Highway 11, known as Chuckanut Drive. This scenic coastal route runs along rocky cliffs and includes narrow, winding sections with sharp turns and limited width. For that reason, Highway 11 is not suitable for trucks, which are advised to use Highway 9. Locals have already complained that some drivers on the detours are speeding and creating hazards, and officials are urging caution in residential areas.
After slope stabilization is complete, contractors will need to remove an additional 5,000 to 6,000 cubic yards of debris. Landslides of this scale are a known hazard in the region, tied to local geology. The area features the Chuckanut Formation — ancient layers of sedimentary rock such as sandstone and shale that are easily eroded by water and prone to sliding along clay seams, especially during heavy rain or seismic activity. Although authorities conduct year-round preventative work, it is impossible to eliminate the risk of recurrence entirely, which is part of life in the scenic but geologically active Pacific Northwest.
Based on: I-5 remains closed near Bellingham as work continues