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WSDOT is studying tolling I-90 between I-5 and I-405 to help ease congestion and move people and goods across Lake Washington. I-90 toll revenue would help complete the unfunded portion of the Cross-Lake Washington Corridor system – the western section of the new SR 520 Bridge. The SR 520 and I-90 bridges work together to form the Cross-Lake Washington Corridor, a system of bridges and roads that connect the region's major employment centers over a 22 mile long body of water.SR 520 tolls are expected to generate $1 billion towards completion of the bridge, while revenues from I-90 tolls would contribute to the $1.4 billion still needed to complete safety and mobility improvements on the SR 520 bridge west approach to I-5.

What are we studying?
In 2012, the Legislature directed WSDOT to study the potential environmental and social effects of tolling on I-90 across Lake Washington. Our environmental assessment will address the following questions about potential tolls on I-90:

• How would WSDOT implement tolling?
• How would tolling affect traffic?
• How would tolling affect I-90 users and surrounding communities?
• What are the other possible effects such as land use, economics, energy and climate change, visual quality, and historic resources?
• What can be done to avoid, minimize or mitigate any potential impacts?

What happening now?
In February 2013, we completed the I-90 Tolling Study scoping process. During the process, we hosted three public scoping meetings and fielded more than 3,000 comments to help determine the range of issues to study in the environmental assessment. These comments, along with feedback from cooperating agencies, are compiled and evaluated to form the final study framework or scope of work. WSDOT will publish the Scoping Summary Report in April.

After scoping is finalized, our technical specialists will use the scoping input to help guide their analysis of project effects. We plan to publish the environmental assessment findings this fall. Sign up for the I-90 study email list to stay updated on the study and learn more about opportunities to comment. To request a briefing or ask questions, please contact us.

What is the tolling decision process?
Tolling I‐90 requires multiple agency approvals. First the Federal Highway Administration must approve the environmental document. Then the Legislature must approve an authorizing bill. Finally, FHWA must a sign a Toll Agreement with WSDOT as part of the federal Value Pricing Pilot Program requirements. Washington is one of 15 states participating in the Value Pricing Pilot Program, a federal platform that encourages states to test and implement tolling to manage highway congestion.

Study timeline

Questions? Contact Us 
Michell Mouton, WSDOT
I90Study@wsdot.wa.gov