(WSDOT photo, March)
In case you missed the mention in our traffic/weather roundup, the full schedule is out for the second wave of northbound 1st Avenue South Bridge repairs to cracked steel deck plates. Here’s WSDOT‘s announcement, which includes word of shuttles for bicycle riders and pedestrians:
Up to three lanes will close across the northbound SR 99 First Avenue South Bridge starting at 9 p.m. each night beginning as early as Monday, May 4, through Friday morning, May 8, to set up a work zone. All lanes will reopen across the bridge each morning by 5 a.m.
All northbound lanes across the SR 99 First Avenue South Bridge will close for bridge repairs:
-From 10 p.m. Friday, May 8, until 5 a.m. Monday, May 11.
-From 10 p.m. to 5 a.m. each night Monday, May 11, until Friday morning, May 15 and Monday, May 18, until Friday morning, May 22.
-Additional night or weekend closures are possible depending on the pace of bridge repairs. …What people can expect
Signed detours will guide northbound SR 509/SR 99 traffic around the bridge closure. Congestion is likely and people should use northbound Interstate 5 or other alternate routes during construction.The First Avenue South Bridge Trail also will close during these times. Accessible shuttle vans operating from signed locations north and south of the bridge will carry pedestrians and cyclists around the work zone.
Maritime traffic under the First Avenue South Bridge will be restricted during construction. Vessels requiring the bridge to open must provide 24-hour notice and confirm their arrival two hours beforehand. These U.S. Coast Guard restrictions will remain in place through June 30, 2026.
Three-phase bridge repair strategy
WSDOT developed a three-phase repair plan after inspectors identified cracks in the steel grid bridge deck in February 2026.WSDOT crews completed Phase 1 repairs in March 2026 during a five-day closure of the bridge. These initial repairs allowed all northbound lanes to reopen across the bridge at a temporary reduced speed limit.
Phase 2 repairs begin Friday night, May 8, and last roughly 30 days. Contractor crews working for WSDOT will replace nine 28-by-9-foot steel deck panels. Once complete, all northbound lanes across the SR 99 First Avenue South Bridge will reopen at normal speeds.
The emergency contract for Phase 2 repairs was awarded to C.A. Carey of Issaquah. The estimated cost is $1.3 million.
Phase 3 repairs will replace remaining steel grid deck plates on the northbound SR 99 First Avenue South Bridge. This work is in the design phase and is currently scheduled for the 2027 construction season.