The last expected total closure of I-405 closure is scheduled over the second weekend of September, which will once again shift routes to smaller roads for those driving between Bellevue and Renton.
The anticipated closure of both northbound and southbound lanes on I-405 will be from 10 p.m. Friday, Sept. 8, to 5 a.m. Monday, Sept. 11. Just like the weekend of Aug. 18, all of I-405 between Sunset Boulevard Northeast (Exit 5) and Coal Creek Parkway (Exit 10) will be closed.
The following lanes and ramps will be closed during the anciticpated 55 hours:
• Sunset Boulevard Northeast on-ramp to northbound I-405
• All ramps at North 30th Street to I-405
• All ramps at Northeast 44th Street to I-405
• Northeast 44th Street over I-405
• All ramps at 112th Avenue Southeast/Lake Washington Boulevard Southeast (Exit 9) to I-405
• Coal Creek Parkway Southeast on-ramp to southbound I-405
Northbound drivers will exit at SR-900/Sunset Boulevard Northeast in Renton and return to I-405 at Coal Creek Parkway in Bellevue. Another option is to follow additional detour signs to rejoin northbound I-405 at Southeast Eighth Street near downtown Bellevue.
Southbound drivers will exit at Coal Creek Parkway and get back on I-405 at North Southport Drive in Renton. Drivers can also exit at Southeast Eighth Street or Lake Washington Boulevard Southeast (Exit 9) and follow additional signs to detour to North Southport Drive.
According to the Washington State Department of Transportation (WSDOT) blog, crews will shift all lanes of I-405 traffic to the new bridge to begin construction of the new southbound alignment during the Sept. closure.
The four-day northbound and southbound closure is part of the I-405 Renton to Bellevue Widening and Express Toll Lanes (ETL) Project.
The Renton to Bellevue project has a ten-year timeline, which began in 2015 and has $705 million in funding. The project will create a two-lane ETL system between SR-167 in Renton and Northeast Sixth Street in Bellevue. The project will add one new lane in each direction and combine the existing HOV lane with the new lane to create a dual ETL system.
The new ETLs will connect to the existing express toll lane system between Bellevue and Lynnwood and the SR-167 High Occupancy Toll (HOT) lanes via the I-405/SR-167 Interchange Direct Connector, to create a 40-mile ETL system.
For construction updates, visit the WSDOT I-405 construction updates webpage.