At about 9:30 p.m. Thursday, March 19, an estimated 3,000-plus cubic yards of boulders, trees, rocks and other debris slid up to 80 feet down a slope near Interstate 5 south of Bellingham. Northbound lanes were immediately closed and remain closed.

Since then, our crews have been hard at work analyzing the slide area, developing detailed plans that require precision and beginning to stabilize the slope. Unfortunately, this is not just a case of loading up the debris that came down and hauling it away. Unsupported boulders, one of which is much larger than a bus, and unstable and loose rocks remain on the slope above.

Our geotechnical engineers began developing plans Friday, March 20. On Saturday we executed an emergency contract with Interwest Construction Inc. (ICI) of Burlington, and they mobilized equipment. ICI began the meticulous, precise process of stabilizing the 250-foot wide slide area on Sunday, March 21. On Wednesday, March 23, specialized workers began scaling work on the slope – rappelling down from above the slide area to remove trees and loose rocks that were unstable. We expect we have a few more days of scaling near the top of the slope, and then we can begin drilling to insert large rock dowels that go deep into the slope to stabilize it and help mitigate the risk for future slides. We will continue this work as we work down the slope, inspecting it carefully as we go.

Unfortunately, this work takes time, and we do not have an estimate when we will reopen I-5. We do not take this lightly – we know that closing an interstate in this area creates disruption to many people and commerce traveling between Seattle and Vancouver, B.C. But this closure is in the interest of safety – both for our crews working at the site and for people traveling through the area.

We are working to reopen I-5 as quickly as it is safe to do so.

Until then, all northbound traffic will exit at North Lake Samish Road (exit 246) and use Samish Way around the closure to get back on northbound I-5. Our freight detour uses State Route 20 to SR 9 to SR 542. Semi-trucks should not use local roads, which are not suitable for freight traffic.

We know this is frustrating, but we ask you to plan ahead, give yourself extra time and consider alternate routes, such as SR 9 or SR 11/Chuckanut Drive. Also please be respectful of the neighborhoods you are driving through – speed limits are not 60 mph like they are on I-5.

For more information

• Check out our project webpage for more information about the work.
• Read our blog for updates about the work we're doing.
• See photos and videos from the slide site on the project Flickr album.

Our bridge maintenance crews closed the northbound lane of SR 9 at Lake Creek Bridge (milepost 42) due to deteriorating deck conditions. A temporary traffic signal will alternate northbound and southbound traffic in the southbound lane until further notice. 

Bridge inspectors will evaluate the condition of the bridge deck on Monday, March 30. Pending that evaluation, bridge engineers will determine the repair plan. There is no estimate for when northbound lanes of Lake Creek Bridge will reopen. 

Please slow down near the work zone and expect delays.

The Lake Creek Bridge is a wood truss bridge built in 1966. Our bridges are inspected on a two-year cycle. The last inspection of this bridge took place in April 2025, and the bridge was determined to be in fair condition.

This bridge is part of a statewide bridge system with infrastructure operating beyond its intended service life. We often extend the life of these bridges through targeted repairs while larger preservation projects are being developed. That approach allows structures to remain in service, but it also means that when conditions change, crews must act quickly and sometimes close lanes or structures in the interest of public safety.

We often have special events and roadwork taking place in the Northend, including construction projects, maintenance and repairs. We always try to minimize any effects to travel, but sometimes it is necessary to close a lane to do the work or create a safe work zone for our crews.

If you spot our crews, slow down and give them space to work! A huge thanks to our crews for all their hard work. 

Want more information? Visit our real time travel center, where these projects and repairs can be found on our travel map, and download our app to receive alerts directly to your smartphone.