The southbound Interstate 5 collector-distributor to Interstate 90 will be reduced to one lane though the weekend while construction crews replace aging expansion joints, according to the Washington State Department of Transportation.
The lanes, as well as the James and Spring streets on-ramps to the collector-distributor will be closed from 10 p.m. Friday to 5 a.m. Monday. Drivers will follow a signed detour, WSDOT said.
The I-5 express lanes will operate southbound from 8 a.m. to 1:30 p.m., each day of the closure.
The stretch of roadway known as the collector-distributor runs parallel to I-5 and provides southbound drivers an option to head east to I-90. Though the closure is not on the main southbound I-5 lanes, downtown Seattle traffic will be congested as exiting drivers merge into one lane. Commuters are urged to use alternate routes such as Highway 99 or Interstate 405 and take earlier downtown exits.
Drivers using Highway 99 can also expect closures this weekend at the south end of downtown Seattle.
The following will be closed from 7 a.m. Saturday to 5 a.m. Monday:
- The South Royal Brougham Way on-ramp to northbound SR 99
- The right lane of northbound SR 99 will be closed at South Royal Brougham Way
- The right lane of southbound First Avenue South will be closed from Railroad Way South to just north of South Royal Brougham Way
All traffic headed to the Eastside from Seattle on I-90 will be diverted to the center roadway express lanes from west of the Mount Baker Tunnel across Mercer Island from 11:30 p.m. Friday to 7 a.m. Saturday. The Rainier Avenue on-ramp to eastbound I-90 will also be closed.
Traffic will be diverted for WSDOT to conduct follow-up testing of new technology to upgrade smoke and fire detection, response and safety inside the tunnels.