Weekend Update: Full SR 520 closure across the lake planned, Southbound I-5 lane and ramp closed near West Seattle Bridge

Drivers should plan for travel delays; I-90, I-405 will be open all weekend

SEATTLE – Travelers should plan ahead and find alternate routes for trips across Lake Washington and southbound Interstate 5 in Seattle. Beginning Friday night, Sept. 30, State Route 520 will close across the lake and southbound I-5 will have closures near the off-ramp to Columbian Way and the West Seattle Bridge.

SR 520 closure

Both directions of SR 520 between I-5 in Seattle and 92nd Avenue Northeast in Clyde Hill and all associated on – and off-ramps will close from 11 p.m. Friday, Sept. 30, to 5 a.m. Monday, Oct. 3.

During the closure, crews will shift the alignment of SR 520 lanes near Seattle’s Montlake neighborhood to create a work zone between the east and westbound lanes. Crews have made significant progress in the area as they as they continue to build a new lid over SR 520 as part of the $455 million SR 520 Montlake Project. The project also builds a new bicycle and pedestrian bridge over SR 520 and new eastbound lanes between Montlake Boulevard and the floating bridge on Lake Washington.  

The SR 520 Trail and I-90 across Lake Washington will remain open during the weekend closure.

Revive I-5 work

Beginning at 10 p.m. Friday, Sept. 30, the off-ramp to Columbian Way and the West Seattle Bridge will close, along with the right lane of southbound I-5 in that area. People going to Columbian Way or the West Seattle Bridge will detour via Michigan Street and back onto northbound I-5 and use the northbound exits. During the closure, crews will work on expansion joints and paving. The work is weather-dependent. All work will finish by 5 a.m. Monday, Oct. 3. 

Mercer off-ramp closed

Starting at 9 p.m. Friday, Sept. 30, crews will also close the southbound I-5 off-ramp to Mercer Street. The ramp closure, part of the SR 520/I-5 Express Lanes Connection Project, will wrap up at 4 a.m. Monday, Oct. .3.  

Keeping travelers informed


Drivers crossing Lake Washington during the weekend should take I-90 as an alternate route or consider delaying their trips if possible. People in Snohomish County going to the eastside should consider using I-405.

With additional traffic using I-90, people who usually travel on I-5 should use alternate routes like I-405 and SR 99 or consider using light rail or bus service. People also should consider rescheduling discretionary trips.

Get the most up-to-date information on closures by visiting the SR 520 Construction Corner or the Revive I-5 project page. Other resources to stay informed:

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