From an August 25, 2021, Sound Transit news release.
Crews working on the Lynnwood Link Extension will be closing the northbound lanes of I-5 north from SR 104 in Mountlake Terrace to 220th Street SW overnight on Friday, August 27th, for construction that will allow the light rail alignment to cross over the highway.
Southbound traffic lanes will remain open.
Starting as early as 11:59 pm on Friday, August 27th, crews will close the northbound I-5 lanes between SR 104 and 220th Street SW until approximately 5:00 am on Saturday morning, August 28th.
During the closure, traffic will be detoured on SR 99 and SR 104 before rejoining I-5.
There will be a uniformed police officer present at the 220th Street SW I-5 northbound on and off ramps during this closure to help manage traffic.
As a result of the construction, the freeway station at Mountlake Terrace Transit Center serving ST Express Route 512 will close at 10:00 pm on Friday, August 27th, through 5:00 am on Saturday, August 28th.
The closure is necessary for a large concrete pour for the future elevated guideway over I-5.
The work being performed will be along the northbound shoulders as well as in the center median of I-5 near the Mountlake Terrace Freeway station.
Drivers should plan ahead and allow extra time to reach their destination.