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SR 520 Program - Costs, Funding and Tolling

Major transportation projects often require innovative and complex funding solutions. The SR 520 Bridge Replacement and HOV Program is no different. This page presents an overview of how the Washington State Department of Transportation plans to deliver a new, safer floating bridge and improvements along SR 520 from I-5 in Seattle to I-405 in Bellevue. How will WSDOT pay for the SR 520 Bridge Replacement and HOV Program?

What is the program’s budget?

In 2009, the Washington State Legislature set a program budget cap of $4.65 billion. In October 2012, updated WSDOT estimates placed the cost of all planned project elements – from I-5 in Seattle to SR 202 in Redmond – at $4.13 billion, or $522 million less than the program’s budget cap. That same year, the Legislature authorized a $2.72 billion budget for constructing a new floating bridge and landings, all needed bridge pontoons, an upgraded Eastside corridor, and the north half of a new west approach bridge in Seattle. The corridor’s remaining improvements in Seattle – they include a new Portage Bay Bridge, two freeway-overpass lids, a second bascule bridge over the Montlake Cut, and the south (eastbound) half of a new west approach bridge – are not yet funded.

What are the current program costs?

In 2014, the Legislature authorized a $170 million increase in funding for the previously approved construction projects. The added funding primarily covers increased costs related to pontoon construction. With the Legislature’s 2014 action, the SR 520 program’s construction budget increased to $2.9 billion. The estimated cost of full corridor reconstruction (including the still-unfunded Seattle segment) increased to $4.3 billion.

The projected cost of full corridor construction is now approximately $350 million below the 2009 budget cap set by the Legislature.

What is currently funded?

The $2.9 billion construction budget pays for:

  • Constructing a new, safer, six-lane floating bridge.
  • Building pontoons at a new facility built in Grays Harbor and an existing facility in Tacoma.
  • Constructing the Eastside Transit and HOV Project.
  • Building the north (westbound) half of the new west approach bridge, which will help connect six lanes of traffic from the Montlake interchange to the new floating bridge.
  • Mitigating the program’s environmental impacts within the corridor.
  • Continuing design work for the remaining elements of the west side of the corridor.

How will WSDOT pay for the SR 520 Bridge Replacement and HOV Program?

The state Legislature has secured a variety of state and federal funding sources, including tolling the existing SR 520 floating bridge, to help pay for the SR 520 construction program.

SR 520 program cost estimate


$4.3 B

Funding received to date


$2.9 B

    State funding (2003 Nickel and 2005 TPA)

$0.58 B


    Federal funding

$0.2 B


    SR 520 Account (tolling and future federal funding)

$1.65 B


    Federal TIFIA loan

$0.30 B


    Deferred sales tax

$0.16 B

Unfunded need (based on 2012 CEVP® cost estimate)



West side cost estimates - 2010 to 2012 comparison

View a graphic (pdf 289 kb) comparing west side cost estimates between 2010 and 2012.

Cost estimates are developed with the WSDOT Cost Esimate Validation Process (CEVP®). View more information about CEVP and Cost Risk Assessment.

Supplemental documents

Cost accountability: 1997 to 2012

Construction activities continue at the east end of Lake Washington near Medina, where crews are building a new east approach structure.

Since 1997, WSDOT has invested more than $1.7 billion on efforts to replace the aging SR 520 floating bridge. The funds have enabled substantial progress on corridor planning, preliminary engineering, design, environmental review, right-of-way purchases, and construction of new SR 520 bridge pontoons, Eastside transit and HOV improvements, and components of the new SR 520 floating bridge.

The Legislature has established a program limit of $4.65 billion. As of April 2014, the SR 520 Program had spent $1.75 billion, or approximately 38 percent of the program cost limit. Additionally, $22 million was spent on the Trans-Lake Study, prior to 2003.

Financial oversight is provided by WSDOT management, the Governor's Office of Financial Management, the Office of the State Treasurer, the Washington State Legislature and the Federal Highway Administration. The SR 520 program produces monthly construction progress reports and financial updates.

Trans-Lake Washington Study (1997-2003)

$22 M


- Evaluated multiple options for a new Lake Washington crossing and decided on a new SR 520 floating bridge.


SR 520 Bridge Replacement and HOV Program

$1.75 B

Preliminary engineering

$385 M


- Addressed legislative requirements for reports, studies, and/or processes.
- Produced nine environmental documents needed for construction permits.
- Completed preliminary or conceptual design for the SR 520 corridor, pontoon casting facility, and pontoons.


Right of way

$112 M


- Purchased properties necessary for construction or mitigation.



$1.25 B


- Continued construction on Eastside, floating bridge and pontoon projects.


Total expenditures to date (through March 2014)

$1.75 B

A helpful summary of expenditures is posted in the Program Library.

SR 520 and tolls

Tolling on the SR 520 bridge across Lake Washington began Dec. 29, 2011.

How do drivers pay tolls on SR 520?
The SR 520 corridor uses all-electronic tolling, meaning no toll booths and no stopping to pay. Tolls are collected electronically from those with a Good To Go! account as vehicles travel at highway speeds. The license plates of drivers without an account will be photographed and they will be able to post-pay within 72 hours or wait to receive a bill in the mail.

How were toll rates set?
Washington State Transportation Commission set toll rates following the Washington Administrative Code process. Tolls on SR 520 vary by the day and time of travel.

What will the SR 520 tolls pay for?
Tolls collected on SR 520 pay for highway improvements, as well as operations and maintenance, debt service, future repairs, insurance, and deferred sales tax.

Was the original SR 520 bridge tolled?
Yes, the SR 520 bridge was tolled from the time it was completed in August 1963, until it was paid off in June 1979. The tolls generated approximately $60 million.

For more information, visit SR 520 tolling.

SR 520 bond sale information

Washington State bonds will be sold in the public markets. Announcements of bond sales will be posted on the website of the Office of the State Treasurer. Underwriters, if any, will be identified at that time. More information can be found here:

The state has no role in administering or interpreting the application of the EB-5 immigrant investor program.

This section is in no way meant to be an endorsement of the EB-5 immigrant investor program. More information about the EB-5 program can be found here: EB-5 Immigrant Investor Program.