Washington State kicks off I-405 widening and Express Lanes project


The Washington State Department of Transportation (WSDOT) has announced the award of a design-build contract to start construction on the Interstate 405 Renton to Bellevue Widening and Express Toll Lanes project.

WSDOT has revealed that the Flatiron West Inc.-The Lane Construction Corporation Joint Venture (Flatiron/Lane JV) submitted the best value proposal of nearly US$705m to complete design and construction of the project. Construction is due to begin in early 2020, and when the project opens in 2024, will add new capacity to create a dual Express Toll Lane system on I-405 between State Route 167 in Renton and Northeast Sixth Street in Bellevue, similar to the dynamically-tolled Express Lanes between Bellevue and Lynnwood. The project will also build two new southbound auxiliary lanes, and rebuild several I-405 interchanges to accommodate the additional roadway.

The project will also build portions of King County’s 42 miles (67km) long ‘Eastrail’ pedestrian and cycling trail and new infrastructure to support Sound Transit’s I-405 Stride Bus Rapid Transit (BRT) system. The I-405 project is designed to improve speeds and trip reliability for all travelers and support the new BRT line. Currently, travelers on this stretch of roadway experience one of the state’s worst commutes, with the new variable toll Express Lanes designed to reduce congestion and improve safety performance along the route, particularly during peak hours. WSDOT expects to give the Flatiron/Lane JV notice to proceed on the first phase of design and construction activities later this year, with construction activities start in early 2020.

“The first phase of the project, the I-405/SR 167 Interchange Direct Connector, opened to traffic in February ahead of schedule and under budget,” said Kim Henry, WSDOT’s I-405/SR 167 program administrator. “This next phase will really be key to improving the challenges facing drivers south of I-90 and will help provide new options for commuters along the entire corridor.”

Sound Transit’s East Corridor development director, Bernard van de Kamp, said, “We have worked closely with WSDOT to implement the region’s long-standing vision for I-405. We have made a significant investment in this project to ensure fast, reliable trips for the thousands of people who will ride Sound Transit’s Stride bus rapid transit every day starting in 2024. With connections to light rail and local transit, Stride BRT will be an important component of the regional transit network.”

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Adam joined the company in 1994, and has been News Editor of TTT since 2009. In his other role as Circulation Manager, he helped create the original Traffic Technology International distribution list 23 years ago, and has been working on it ever since. Outside of work, he is a keen fisherman, runs a drumming band, and plays an ancient version of cricket.