By Lauren Penning
In the last year, crews have made rapid progress reshaping the interchange at SR 522 and I-405. Now we are ready to move to the next phase of construction on the I-405 Brickyard to SR 527 Improvement Project. This means traffic needs to shift on SR 522 at the I-405 interchange.
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Map showing where crews will shift traffic on SR 522 at I-405. |
What to expect while we do the shift
Starting at 11:59 p.m., Friday, April 18 to 6 a.m., Saturday, April 19:
- SR 522 will be a single lane each direction at I-405
- Westbound SR 522 ramp to northbound I-405 closed with signed detour in effect
Drivers should slow down as they approach the work zone. Watch for changing traffic control as crews shift eastbound and westbound traffic to the newly paved section of SR 522 further north.
Progress on Par Creek fish passage
This shift means traffic will move over the newly completed section of the Par Creek fish passage. This fish passage will run under SR 522 at I-405. We completed the first section of the fish passage in late 2024. Since then, westbound SR 522 ramp traffic has been traveling over that new section. Now we’ve completed the second portion of the passage and are ready to shift traffic again. This will free up space to begin construction on the south portion.
The Par Creek fish passage will connect the Sammamish River with Par Creek, allowing for natural stream processes that help protect and restore salmon runs. In total, this project will remove six fish barriers and create new habitat area.
Reminder to slow down to 35 MPH
A year ago, we reduced the speed limit on SR 522 near the I-405 interchange from 60 to 35 MPH. We made this permanent change for the safety of our crews. This speed limit also reflects how drivers will navigate this road in the future.
Despite this change, our crews still regularly see traffic speeding through the area. They often see drivers far exceeding the posted speed limit. We are asking drivers to slow down on SR 522 near the I-405 interchange for the safety of our crews and all travelers.
New route to SR 522 from northbound I-405 coming in late 2025
This project adds direct access to the I-405 express toll lanes (ETLs) at the SR 522 interchange. These ramps will be available for HOV and ETL users and Sound Transit Bus Rapid Transit (BRT). It also provides infrastructure to support BRT service along I-405. These new connections mean changes to the I-405/SR 522 interchange.
Key Changes:
- New traffic signal in late 2025 will control two movements :
- Eastbound SR 522 to northbound I-405: New left turn at signal, no more loop ramp.
- Northbound I-405 to west SR 522: Use new signal, no more flyover ramp.
- More signals: Two more added by 2028.
Important Dates:
- First signal: November 2025
- Project completion: 2028
Expect ongoing updates before each major change.
Thank you for your patience as we continue this work. Improvements to this 4.5 mile stretch of I-405 through Bothell will benefit drivers, riders, and many other travelers. Check out the WSDOT real-time travel map for up-to-date information. If you have any questions and/or you would like to sign up for project updates, please email I405SR167Program@wsdot.wa.gov. Stay informed by subscribing to WSDOT updates for King County.
If you do not put roundabouts instead of traffic lights you will always have a congestion and heavy traffic.
ReplyDeleteAre we seriously putting stoplights here. It feels like we have far better options now days. These better be synchronized at the very least.
ReplyDeleteBobby, thank you for your comment. This design decision was made after many discussions about tradeoffs and is necessary to enable improvements for the I-405/Brickyard to SR 527 Improvement Project including new direct access ramps to the express toll lanes (ETLs), infrastructure to support Sound Transit’s Stride bus rapid transit, and the addition of another ETL lane. This design configuration allows the project to keep much of the existing bridges and roadway helping to minimize cost.
ReplyDeleteAfter additional iterations and close coordination with our partners, including the City of Bothell and Sound Transit, we found the addition of three new signals was the best option to meet the needs of many different users and enable improvements to the interchange. While adding the traffic signals requires modifications to the existing configuration, the overall benefits of transit connectivity and improved traffic flow on I-405 are significant.
We acknowledge that this will be a change for drivers that use the interchange. However, our traffic analysis shows that when implemented, the signals will add approximately one additional minute to SR 522 travel during peak hours. To help minimize delay and keep traffic flowing, we will time the signals to work together so that vehicles can move efficiently through the interchange with minimal stoppage time.