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For information regarding content related issues please contact the project manager Julie Meredith at
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SR 520 Bridge Replacement and HOV Project

    SR 520 - I-405
Photo of SR 520 looking west.
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Public Meeting
Photo of a Project Open House.
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Get Involved Today

Public Meetings are scheduled throughout the project and details are posted to this site. Please check back periodically for updates.

Why is WSDOT Doing This Project?

The Washington Department of Transportation's (WSDOT) commitment is to move toward a solution for Seattle and eastside citizens and businesses for improving cross-lake Washington travel. With YOUR input, we're working on designing and evaluating potential solutions.

What's happening on SR 520?

The purpose of the SR 520 Bridge Replacement and HOV Project is to improve mobility for people and goods on SR 520 while minimizing negative impacts on neighborhoods and the environment. Aging portions of the corridor are nearing the end of their design life, and need replacement.

To get there, a 47-member Study Committee took a comprehensive look at improving the way people move across and around the lake and made several recommendations. Three committees, supported by a technical team, are carrying the recommendations forward into further design and evaluation. An environmental impact statement will help the project's lead agencies and committees select a final preferred alternative for implementation.

What's Being Done to Protect the Environment

Both WSDOT and Sound Transit are committed to environmental stewardship. For example, there will be opportunities on SR 520 to better manage stormwater runoff for the benefit of salmon and other aquatic species. Another environmental improvement being planned includes reducing the amount of noise pollution from SR 520 in surrounding neighborhoods by the use of noise walls or other methods.


Safety on SR 520 is a top priority for WSDOT and Sound Transit. Currently, there are no shoulders or pull-out areas along the floating bridge and other areas of the corridor. All potential improvements will include adding shoulders and/or pull-out areas to the corridor to increase safety.

How would traffic be affected by earthquake damage to the SR 520 Bridge?

WSDOT, through computer modeling, estimates that if the SR 520 Evergreen Point Floating Bridge were to suffer a seismic failure, travel time between Downtown Seattle and Redmond would nearly double from an average of 33 minutes to 55 minutes during the PM peak period. I-90, I-405 and other nearby arterials would also experience significant delays. Overall, a earthquake-induced disruption in traffic across the 520 Bridge would cost the region an additional 33,000 hours of delay during the peak periods following its breakdown. The sooner the bridge is replaced, the less likely we will see this scenario come to fruition.

To learn more about WSDOT's congestion relief efforts visit WSDOT's Congestion site.

Public Involvement

The SR 520 Bridge Replacement and HOV Project planning process allows for many opportunities for public participation. These include public meetings and workshops, community briefings, and access to this website and other information materials. If you would like to schedule a presentation or share your ideas with WSDOT, please contact us.

Government-to-Government Tribal Consultation Process

Government-to-Government consultation has been initiated between FHWA (on behalf of WSDOT) and the Muckleshoot, Tulalip, Snoqualmie, Suquamish, and Yakama Nation tribes. WSDOT will continue to coordinate directly with the tribes throughout project development.

Financial Information

In 2003, the Washington State Legislature passed a nickel-funding package, which raised $56.5 million for this project. This funding will go toward environmental review, significant design, and early right-of-way purchases.

In July 2003, WSDOT released updated cost estimate ranges for the plans being considered the replace the vulnerable Evergreen Point Floating Bridge. These updated estimates reflect new information about the plans and take into account risks and opportunities that may affect cost or schedule. For more information about the Cost Estimate Validation Process and the cost estimate ranges, please visit the CEVP website.

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