Both directions of I-405 in Bothell to close for ramp removal, March 7-9 and March 13-16

BOTHELL - Construction across the greater Puget Sound region continues to intensify as multiple projects move forward at the same time. As part of that sustained work, both directions of Interstate 405 in Bothell will fully close during the first two weekends of March so crews can remove the remaining portion of the previous northbound I-405 to State Route 522 ramp over I-405.

Closure details

March 7-9: 6 p.m. Saturday, March 7, to 4 a.m. Monday, March 9, crews will close all lanes of northbound I-405 at the SR 522 Interchange and all lanes of southbound I-405 from SR 527 to SR 522 to remove ramp sections over I-405.

March 13-16: 9 p.m. Friday, March 13, to 4 a.m. Monday, March 16, crews will close all lanes of northbound I-405 at the SR 522 Interchange and all lanes of southbound I-405 from SR 527 to SR 522. All lanes of southbound I-405 may reopen as early as 9 a.m. Sunday, March 15, depending on ramp removal progress.

Ramp closures

Ramp closures are required overnight to restripe the northbound I-405 detour route temporarily to two lanes to increase capacity and again to reset the lanes. Travelers can expect closures of the following ramps overnight:

• The northbound I-405 on-ramp to westbound SR 522.
• The eastbound and westbound SR 522 on-ramps to northbound I-405.

During the southbound I-405 full closures the following ramps will also close:

• SR 527 on-ramps to southbound I-405.
• Northeast 195th Street on- and off-ramps (exit 24) to southbound I-405.

This work is part of the I-405/Brickyard to SR 527 Improvement Project, which expands and enhances 4.5 miles of I-405 through Bothell. Full closures of I-405 are necessary to keep drivers safe and protect the I-405 bridge deck below the ramp during its removal.

"We learned a lot during the removal of the first few sections of these ramps over SR 522," said I-405/SR 167 Program Administrator Lisa Hodgson. "Now we need to close I-405 to remove the remaining portions of ramp. Leveraging our lessons learned from the previous ramp sections, we are able to reduce the time we plan to fully close I-405 on both weekends. However, we still expect these closures to have significant impacts to regional travel."

Detour routes

Signed detour routes will be in place:

• Northbound I-405 nighttime detour: In place while crews restripe lanes for daytime detour and reset lanes before reopening to traffic Monday morning.
• Northbound I-405 daytime detour: Westbound SR 522 traffic will make a right turn at the traffic signal instead of using the merge ramp to help prioritize northbound I-405 traffic.
• Southbound I-405 detour.

Drivers are advised to slow down and pay attention through the detours. Uniformed police officers will help direct traffic.

Effect on traffic

Detour routes are limited and cannot carry normal I-405 freeway volumes. Travelers should expect 2- to 3-mile backups on I-405 during the full closures. A one-hour delay in both directions is the best-case scenario during peak travel times.

Northbound I-5 through Seattle also is restricted to two lanes for the Revive I-5 work and t he two right northbound SR 99 lanes have an emergency closure at the First Avenue South Bridge. These restrictions will limit northbound travel options through the Seattle metro area both weekends. The I-5 express lanes are open northbound-only 24 hours a day for people going north of downtown Seattle. There are no northbound express lane exits to downtown.

Over the next two years, travelers across Greater Puget Sound will see an unprecedented level of construction activity. The region's transportation system is at a tipping point. Much of the infrastructure is old, overstressed and operating beyond what it was designed to handle. Meanwhile, the region's population continues to grow and must be managed safely and strategically. That means adding capacity to roads, improving access and strengthening transit connections. More information about WSDOT's efforts were recently shared on the WSDOT blog: "Why so much construction in Puget Sound? What to know about I-5, I-405, SR 520 and more through 2028."

People should plan ahead and prepare for longer travel times, use alternative routes or consider delaying trips. Real-time travel information is available on the WSDOT mobile app, the WSDOT Travel Center Map or by signing up for WSDOT's email updates.

About the I-405/Brickyard to SR 527 Improvement Project

The work happening this weekend supports opening the center of the interchange to build a new northbound bridge deck allowing, which will expand I-405 through Bothell. The project will add an express toll lane along each direction of I-405, direct access ramps to the ETLs and will help enable Stride Bus Rapid Transit service, with buses arriving every 10 minutes for most of the day.

These improvements will benefit drivers, transit riders and freight mobility across the region. Additionally, the project is addressing aging infrastructure, restoring stream connections, adding noise walls and new stormwater facilities.