All lanes of I-405 will be closed between Renton and Bellevue this weekend
What do the Seahawks, their Eastside fans, and people living between Renton and Bellevue all have in common this weekend? They will find it incredibly hard to get to and from their homes.
I-405 as a freeway might as well not exist this weekend for anyone with plans between Renton and Bellevue. All lanes of the freeway, in both directions, will be closed from 10 p.m. Friday night to 5 a.m. Monday morning.
All northbound drivers will be forced to exit at Sunset Boulevard in Renton. All southbound drivers will be forced to exit at Coal Creek Parkway in Factoria.
Coal Creek Parkway is your only detour route.
“It’s a long detour through city streets, businesses along the way, and lots of stoplights,” the Washington Department of Transportation’s Craig Smiley said. “We will have uniformed police officers all along the route to help prioritize traffic through the area. We’ve also worked with the City of Renton and the City of Bellevue to optimize signal timing and try to do our best.”
A closure like this will have a regional impact.
“We’re expecting some pretty impactful traffic problems around the area with this,” Smiley said. “About 400,000 cars use this route on any given weekend so our detour routes are going to be very heavily trafficked.”
You can expect a lot more traffic on I-5, the lake bridges, and even the local streets around the top and bottom of Lake Washington, like Renton and Kenmore.
What is so important that the state needs to shut down a major freeway during a summer weekend?
“We’re installing a new fish passable culvert under I-405,” Smiley said. “We’re cutting a 30-foot wide 30-foot deep trench all the way across the freeway, installing a big box culvert, and covering it back up in three days.”
I asked Smiley why this couldn’t have been done at another time. “We need weather,” he said. “We need clear, dry weather to be able to get this work done and maximize production to be able to get that much work done in three days. We also have to work within a fish window. A period of time that fish are moving in and out for spawning. It’s specified by Washington that we have to get this done ahead of the upcoming season.”
But it’s not just the fish culvert. Other drainage work and expansion joint repair in the closure area will also be completed.
“We’ll have over 100 people on site doing construction this weekend,” he said. “We’re looking at 7000 cubic yards of material that will be excavating and replacing and over 1000 square feet of pavement will be replaced.”
This work is all part of the expansion of the express toll lane system on the east side and a complete redesign of the 44th interchange.
Workers are almost finished with the new northbound section of 405 at the interchange, and Smiley said a huge lane shift is about to happen.
“In September, all of the traffic on I-405 northbound and southbound it’s going to get flipped over to that new alignment,” he said. “Then we can demo the Northeast 44th Street Bridge and Northeast 44th Street will actually go underneath the freeway.”
When the 44th interchange is done, there will be matching bridges taking 405 over a newly constructed 44th Street. There will be a direct access bus and HOV exit that will drop down in the middle of those new bridges.
It’s expected to open in mid to late 2025 when the entire widening project from Bellevue to Renton is complete.
This will also coincide with the extension of the HOT lane on southbound 167 from Auburn to Sumner.
That’s when the entirely new express toll lane system will begin, where drivers will be able to buy their way into faster lanes from Lynnwood to Sumner without having to exit the express toll lanes.
