What's being done to ease traffic on I-405?



BOTHELL, Wash. -- Most commuters on the East Side are already well aware of the backups on I-405 during the morning and afternoon rush hours, and, while efforts to alleviate backups with Express Toll Lanes have worked for a good stretch of Bellevue and Kirkland, Residents near Bothell and further North continue to feel the pressure. It’s a reality Kim Henry, the 405/167 Program Administrator for WSDOT is well aware of.

"We’ve got huge growth and huge demands coming out of South Snohomish county, and all the way up the I-5 corridor, all that growth has been occurring in through there. And that overall demand just exceeds the capacity and that really causes us to struggle," Henry said.

The immediate fix for Northbound drivers on I-405 comes in the shape of peak drive time shoulder use lanes. A change that not only added capacity but also lowered tolls through the region by raising speeds and giving drivers more options. Southbound commuters don’t get that same option though, they instead hit the same bottleneck at 522. So what’s the big fix? Comparing the old interchange of 405 and 522 next to a proposed model.

"Our strategy is to build a brand new bridge right to the East there, that’ll carry the Northbound Traffic, and then the other two existing bridges can carry Southbound traffic, and so now we’ve got additional capacity for both directions of travel," Henry said.

Henry explains it’s that capacity that is crucial to keeping the overall throughput on the roads at a much better pace. But, with the vast majority of improvements along 405 beginning next year in the South end, places like Renton, when can residents to the North expect some form of relief?

"We can either build the whole thing all at once or we could do it in phases, and so part of our schedule is if we wanted to build everything at once and we were just given the go-ahead to just do that and the funding was there to build it, we’d be starting construction in 2021 by the time we got through all the environmental process and all the engineering and got a contract out and under way and it could be complete by 2024," she said.

This, however, would require additional state funding. Another option to fund the project might come solely from express toll revenues with construction finishing in 2033. More than likely it’ll take some combination of state funds and toll revenues to get the project done.

From all of this, two things are certain, the use of express toll lanes has in fact been a positive impact on throughput of the roads AND, the revenues being generated are providing a solid shot in the arm for major projects along 405 that might not otherwise be possible. While it could take a while to get there, at least we have one way to go.