Bellevue drivers heading south on I-405 toward Renton this weekend will need to find another route. All southbound lanes between Coal Creek Parkway Southeast and North 30th Street close nightly from 11:30 p.m. Friday, Aug. 21, through 4 a.m. Monday, Aug. 24.
The closures are part of the $705 million I-405/Renton to Bellevue Widening and Express Toll Lanes Project, according to WSDOT. Crews will use the nightly windows for drainage work, repaving and a traffic switch.
Ramp closures compound the impact
Six ramps will also shut down during the same nightly windows:
- Coal Creek Parkway SE on-ramp to southbound I-405
- Lake Washington Boulevard on-ramp and off-ramp (Exit 9)
- Northeast 44th Street on-ramp and off-ramp (Exit 7)
- Southbound I-405 off-ramp to North 30th Street (Exit 6)
No way in or out of southbound I-405 within the closure zone during those hours.
Lane reductions start Thursday night
Bellevue-area drivers may hit slowdowns even before the full closure begins. Up to four southbound lanes between milepost 14.25 and Coal Creek Parkway SE will close nightly from 9 p.m. to 5 a.m. starting Thursday, Aug. 20, through Monday, Aug. 24.
Detour and what's next
A signed detour will be in place, though the specific detour streets for the southbound direction have not been announced. The city of Bellevue's traffic advisory page confirms the closure and notes that schedules are weather-dependent and subject to change.
The weekend closure follows a series of northbound I-405 shutdowns in the same corridor earlier this month. A full northbound closure ran Aug. 7–10, and overnight northbound closures followed Aug. 12–13.
The wider project will add one lane in each direction and create a dual express toll lane system between SR 167 in Renton and Northeast Sixth Street in Bellevue, connecting to the existing ETL network to form a 40-mile system. WSDOT expects the project to open to traffic in summer 2027.
Drivers with questions can call WSDOT's 24-hour construction hotline at 425-818-0161 or email [email protected] for updates.
