Landslide closes northbound I-5 in Bellingham and a look at the work it takes to reopen the highway

By RB McKeon and David Rasbach

Landslide blocks all northbound lanes of I-5 near Bellingham

Update: 11 a.m. Friday, April 3

It's been two weeks since the March 19 slide that closed northbound Interstate 5 south of Bellingham. Though we do not have an estimate when lanes will reopen, our crews have been working seven days a week and will reopen northbound I-5 as quickly as it is safe to do so.

Earlier this week, we wrapped up scaling work on the top of the slope and began drilling holes to anchor 15- to 25-foot-long steel dowels. These dowels are placed in a pattern designed by on-site geotechnical engineers to help stabilize the slope. This work requires geotechs to constantly reassess the slope and adjust plans.

Near the bottom, crews are breaking up the largest boulders, including the "bus-sized" rock in the middle of the slope. On Wednesday, April 1, crews broke off a large section of that boulder using expansive grout and then used an excavator to break it up further. The boulder is so large, we'll have to repeat the process several times.

Geotechs still need to get a good look at what lies beneath the debris pile to develop plans to stabilize the bottom of the slope. Until we are able to do that work, northbound I-5 will remain closed at North Lake Samish Road (exit 246).

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Update: Friday, March 27

The work on northbound I-5 just south of Bellingham is a top down operation, meaning that crews must first stabilize and secure the upper portion of the slope before working their way down. As they do that, the geotechnical engineers on site are continuing to assess conditions and define the full scope of work in real time.

This past week, specialized crews began rock scaling on Wednesday, March 25, removing loose rock and hazard trees that could fall and cause more of the slope to slide. They started on the west side of the slide area and are moving east.

As scaling crews move east, drilling crews will begin setting anchors for their equipment. They expect to start drilling holes for steel dowels that will further stabilize the slope by Sunday, March 29. Crews also began using expanding grout to break boulders Friday, March 27.

Northbound I-5 remains closed, and we do not have an estimated timeline for reopening, but we will continue to provide updates.

Freight traffic should continue to detour using eastbound SR 20, northbound SR 9 and westbound SR 542. All other traffic will be diverted at North Lake Samish Road (exit 246) and is encouraged to consider alternate routes, such as SR 9 or SR 11/Chuckanut Drive. We ask drivers to be patient and follow the speed limits and traffic laws on the roads they are using.

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Original post:

A landslide has closed all lanes of northbound I-5 near Bellingham on, with large rocks, soil and trees across the roadway and an unstable slope.

Around 9:30 p.m. on Thursday, March 19, two landslides came down onto northbound I-5 near milepost 248, closing all northbound lanes between North Lake Samish Road (milepost 246) and Fairhaven Parkway (milepost 251). The slide brought about 2,000 cubic yards of rock, soil and trees onto the roadway.

Some of the rocks are the size of pickup trucks and several are larger than a metro-bus, tumbling from 60 to 80-feet above and are now unstable and unsupported. The debris stretches about 250-feet along the highway and is up to 65-feet tall in places.

What WSDOT is doing

Heavy machinery used to break apart large rocks along northbound I-5 near Bellingham as crews begin clearing debris from the landslide area.

This is more than clearing debris. It is complex, specialized work and safety is at the core of every decision.

Geotechnical engineers have been on site since shortly after the slide, working to understand what’s happening on the slope, not just what came down on Thursday, but what could still come down.

WSDOT executed an emergency contract on Saturday, March 21, selecting Interwest Construction, Inc. as the contractor to perform the work needed to reopen the freeway.

Here’s what that work looks like:

Assessing the slope: Engineers are evaluating conditions above and behind the visible rock face, including cracks that can’t be seen from the roadway.

Clearing what’s safe: Crews are removing some debris from the bottom of the slide and breaking apart larger rocks so they can be hauled away.

Scaling the slope: Specialty crews using hand tools and compressed air are beginning to remove loose rock from the hillside, working from the top down to reduce risk.

Stabilizing the slope: Crews will shift between scaling and rock bolting – the process of drilling deep into the rock face and securing it to help prevent additional movement.

In some areas, the debris is actually helping to hold unstable rock in place. Removing it too soon could trigger another slide.

Crews are working seven days a week, but some of this work can only happen during daylight hours and under certain weather conditions.

We are moving as quickly and safely as we can to return the freeway to normal operations.

Why is the road still closed?

We know one of the biggest questions is: Why can’t you clear road and reopen at least one lane? Right now, it is not safe to do that. There is still unstable rock above the roadway that is unsupported and could fall. Crews are actively working on the slope, and we cannot have traffic moving through an active work zone where rocks could come down. Also, some of the debris that is remaining on the road is acting as a buffer, helping to protect the road surface and prevent additional damage.

Until we understand and stabilize what’s above the highway, reopening, even partially, is not possible. We do not have an estimated timeline for reopening.

What travelers need to know

Northbound I-5 remains fully closed between North Lake Samish Road (milepost 246) and Fairhaven Parkway (milepost 251). Southbound I-5 is open and unaffected by this slide.

Detours and alternate routes are available:

• SR 9 is the preferred route for freight
• SR 11/Chuckanut Drive is available for passenger vehicles but not suitable for freight.
• NB I-5 is being pushed off at exit 246 North Lake Samish

When a major highway like I-5 closes unexpectedly, drivers often follow directions from navigation apps, even onto roads that are not intended to handle that volume or type of traffic.

Traveler resources

• Visit the WSDOT travel map for real-time travel and traffic conditions
• Follow along on social media: X, BlueSky, Facebook, Instagram, Threads, and TikTok
• Sign up for email alerts
• Project page: Northbound I-5 Bellingham Slide – Emergency
• Project photos: Northbound I-5 slide near Bellingham
• Plan your route:
• SR 9 is the preferred route for freight
• SR 11/Chuckanut Drive is available for passenger vehicles
• As a reminder, WSDOT does not control third-party apps like Google, Waze or Apple.

Why this area is prone to slides and what we do to reduce risk

layers of soil and rock are visible on the exposed slop above northbound I-5 near Bellingham, where geotechnical engineers are assessing stability following the landslide.

This stretch of I-5 runs along a steep hillside made up of layered soils, rock and glacial material. In places, those layers can hold water and shift over time, especially during periods of sustained wet weather.

That combination of steep slopes, complex geology and moisture means this area is naturally prone to landslides.

Our maintenance crews regularly:

• Remove hazard trees and manage vegetation
• Clear drainage systems to move water away from slopes
• Inspect and maintain areas with a history of movement
• Install features like catchment areas or barriers designed to capture smaller debris before it reaches the roadway

You can see some of that work along I-5, including barriers meant to catch smaller rocks and debris. Large-scale slides like this, where significant amounts of material come down from higher on the slope, are much harder to predict and prevent. That’s especially true when there is movement happening above the visible rock face.

That’s why the work happening now is focused not just on clearing what came down but understanding and stabilizing what remains above the highway.