The Washington State Department of Transportation (WSDOT) released a key environmental report today, marking a major milestone toward replacing the vulnerable SR 520 floating bridge and selecting a preferred interchange design for the west side of the SR 520 corridor.

The report, called a supplemental draft environmental impact statement, analyzes three designs for the interchange in the Montlake area, as well as the effects of building a new six-lane SR 520 floating bridge and roadway from I-5 to Medina.

“Knowing the effects of the three interchange options on the west side of the corridor and hearing the public’s comments will help us select the design that best balances costs, environmental effects, roadway operations and community interests,” said Paula Hammond, Washington Transportation Secretary. “Releasing this report today keeps us on schedule to open a new bridge in 2014 that will better withstand earthquakes and windstorms.”

All proposed interchange designs improve regional traffic flow, making driving and commuting across SR 520 safer and more reliable. The report shows:

• Buses and carpools are expected to see travel time benefits once high-occupancy vehicle lanes are added to the SR 520 floating bridge and corridor. In 2030, eastbound commuters in the HOV lane during the heaviest traffic will travel up to 40 minutes faster if the project is built.

• Stormwater from the roadway will be treated before it reaches Lake Washington.

• Greenhouse gas emissions are expected to be lower in 2030 than if the project is not built.

• Neighbors will hear less traffic noise because of noise reduction measures along the highway.

• Bicyclists and walkers will be able to cross the lake on a 14-foot-wide regional path.

• Drivers will have wider, safer freeway lanes and shoulders.

The report expands on a draft environmental impact statement released in 2006 and launches a public review and comment period that ends March 8. The Washington State Legislature has endorsed a six-lane replacement for the corridor, which includes two new HOV lanes.

Earlier this month, the SR 520 Legislative Workgroup issued a final report with recommendations for the SR 520 program. The panel recommended an interchange design for the Montlake area and financing options for the entire SR 520 program. WSDOT will review and consider the report’s legislative input and comments from the public before settling on a preferred option later this spring.

In 2009, Gov. Gregoire and the Legislature authorized tolling on the existing SR 520 bridge. Tolls are scheduled to be collected beginning in spring 2011. Funding from tolls builds a new pontoon construction site in Grays Harbor County later this year and pontoons at that site beginning in 2012. A new floating bridge is scheduled to open for drivers in 2014. The governor and Legislature established a total project budget of $4.65 billion.

Visit the SR 520 program Web page for more information: www.wsdot.wa.gov/projects/sr520bridge.