WSDOT and Sound Transit are adding high occupancy vehicle (HOV) lanes to both directions of the I-90 mainline between Seattle and Bellevue. This project preserves the three existing general purpose lanes in each direction while adding all-day HOV lanes as well as direct access ramps for transit, carpools, and vanpools. This work will also allow Sound Transit to construct the East Link light rail extension in the existing I-90 express lanes.
Changes coming for drivers in mid-2017
In mid-2017, the new mainline HOV lanes will open and the express lanes will close. There is still a lot of work to do before the new HOV lanes open. Drivers can expect up to two weekend-long closures per month until the express lanes close. The closures will allow crews finish work inside the Mount Baker and Mercer Island tunnels as well as restripe more than 14 miles of roadway.
Learn more about the changes coming to I-90 across Lake Washington and what they mean for you. This is a big change for everyone that uses I-90 across Lake Washington and it will take time for people to adjust to new habits and traffic patterns. It could take months for traffic to settle into its new routine. The new outer roadway HOV lanes will provide carpools and transit a more reliable commute on I-90 that doesn’t depend on the direction of the express lanes.
Why is WSDOT
working with Sound Transit on I-90?
WSDOT is collaborating with Sound Transit to make the best use of taxpayer transportation dollars by moving more people, more efficiently through one of the state's busiest rush-hour commutes.
Currently I-90 includes two reversible express lanes between Seattle and Bellevue for buses, carpools and vanpools. In the morning, traffic in the express lanes are westbound; in the evening they go eastbound. Buses and high-occupancy vehicles traveling opposite the express lanes must use the mainline. With no HOV lanes on the outer roadway at the start of this project, buses and carpools experienced routine, rush-hour delays, undermining the benefits of ride sharing. The new mainline HOV lanes will provide a more reliable commute for carpools, vanpools, and transit that doesn't depend on the direction of the express lanes.
The End Result
The project will improve on-time reliability and access for transit, carpools, and vanpools on I-90. With new direct-access ramps, carpools, vanpools and buses will access the freeway directly to or from HOV lanes without merging across three or more lanes of traffic. Traffic on the mainline will be smoother and safer for everyone.
The project also prepares the center roadway for Sound Transit's 14-mile East Link light rail extension from Seattle to Redmond.
- Safety: Reduces weaving and merging on I-90
- Improved transit, vanpool, and carpool reliability: Provides around-the-clock HOV lanes in both directions for transit, vanpools, and carpools making commutes more reliable.
- Environment: Adds to existing drainage and storm water treatment systems to clean roadway runoff.
What is the project timeline?
- March 2007-October 2008 – Stage 1 construction
- January-May 2010 - ARRA funded pavement preservation construction
- Spring 2010-March 2012 - Stage 2 construction
- May 2014-May 2015 - Stage 3A construction
- January 2015-mid-2017 - Stage 3 construction
Learn more about what was built during each stage.
The following funding sources help fund the project:
How can I get more information?
Sound Transit Community Outreach
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