Washington State Department of Transportation (WSDOT) announced that southbound Interstate 405 will be fully closed during nighttime hours from Friday, Aug. 21 through Monday, Aug. 24. The closures affect the stretch from Coal Creek Parkway Southeast to North 30th Street, covering the corridor between Bellevue and Renton.
Details of the closures
All lanes of southbound I‑405 in the specified segment will be closed nightly from 11:30 p.m. to 4 a.m. Drivers are instructed to follow signed detours that will be in place for the duration of the work. In addition to the mainline closure, several on‑ramps and off‑ramps will also be shut down during the same hours:
- Coal Creek Parkway Southeast on‑ramp to southbound I‑405
- Lake Washington Boulevard on‑ramp to southbound I‑405
- Southbound I‑405 off‑ramp to Lake Washington Boulevard
- Northeast 44th Street on‑ramp to southbound I‑405
- Southbound I‑405 off‑ramp to Northeast 44th Street
- Southbound I‑405 off‑ramp to North 30th Street
Northbound I‑405 will also see lane reductions and HOV lane closures throughout the same week. Up to three lanes between State Route 167 and Sunset Boulevard North will close nightly from 9 p.m. to 5 a.m. Friday, Aug. 21‑24. The HOV lane between Interstate 90 and Southeast Eighth Street will be closed nightly from 9 p.m. to 5 a.m. beginning Wednesday, Aug. 19 through Monday, Aug. 24. Additional lane reductions are scheduled between I‑90 and Southeast Eighth Street, and from milepost 12 to Northeast Fourth Street, with varying nightly and overnight windows.
Impact on commuters
Motorists traveling southbound on I‑405 should plan alternate routes or adjust travel times to avoid the nightly closures. The posted detours will guide drivers onto nearby surface streets and parallel highways. Residents of Bellevue, Renton, and surrounding communities are encouraged to stay informed through WSDOT’s website and local traffic alerts.
Long‑term project context
The closures are part of the larger I‑405/Renton to Bellevue Widening and Express Toll Lanes Project, which is slated for completion in 2027. The project will add new express toll lanes that connect to the existing system between Bellevue and Lynnwood, as well as to the SR 167 HOT lanes via a direct connector at the I‑405/SR 167 interchange. The improvements aim to increase travel speeds, improve trip reliability, and support the upcoming I‑405 Bus Rapid Transit (BRT) line that will run between Lynnwood and Tukwila.
Commuters should monitor updates from WSDOT, especially if travel plans involve the affected ramps or the northbound lane reductions. While the nighttime closures are intended to minimize disruption during peak travel periods, drivers may still experience increased travel times on alternate routes.
Where to find more information
For the latest detour maps, traffic alerts, and project updates, visit the WSDOT website or follow local news outlets covering the Seattle‑Eastside corridor. The agency will provide real‑time information on any changes to the closure schedule.
Original reporting: Renton Reporter — read the source article.
