Sound Transit’s Crosslake Connection: Rail, Retrofit, and Innovation
Sound Transit’s Crosslake Connection represents one of the most technically ambitious rail transit projects ever delivered in North America. Forming the central segment of the Link Light Rail 2 Line, the project converted the I‑90 corridor—including the iconic Homer M. Hadley Floating Bridge—from reversible highway lanes to exclusive light rail service. As Sound Transit’s prime engineering consultant, WSP led the final design of this unprecedented crossing, delivering the world’s first light rail system to operate on a floating bridge. Crossing the floating bridge required the development of a patented “Track Bridge” system at the expansion joints to accommodate the floating bridge’s continuous movements and non‑invasive track attachment solutions to protect the bridge pontoons.
Beyond the floating bridge, the Crosslake Connection project encompassed extensive seismic and gravity retrofits of existing highway structures repurposed for rail, along with the design and delivery of Judkins Park and Mercer Island Stations, each with unique structural and architectural challenges. The project demanded close coordination with Sound Transit and WSDOT to integrate new rail infrastructure into existing highway right-of-way. This presentation will explore the engineering innovations and collaborative problem‑solving that transformed an existing highway corridor into a resilient, high‑capacity rail connection.
Speakers
Matthew Barber, PE
Matthew Barber is a bridge engineer working in the greater Seattle area. He started his career 22 years ago in the New York office of Parsons Brinckerhoff (now WSP) before coming to the Northwest in 2011 to support a WSDOT design build project. On the Seattle to South Bellevue segment of East Link (currently referred to as the Crosslake Connection), he started as the Miscellaneous Structures Lead during the Final Design, before serving as the Design Lead During Construction for the duration of the construction. When not thinking about transportation infrastructure, Matthew enjoys gardening, cycling, kayaking, cooking pasta with wife, and volunteering at the snack bar of his children’s swim meets.
Jake Douglass, PE
Jake Douglass is a bridge engineer in WSP’s Seattle office. Prior to joining WSP, he lived and worked on the East Coast, designing and inspecting bridges and waterfront structures. Jake joined the design team for the Seattle to South Bellevue segment of East Link in 2016 during the latter stages of final design and later became the Deputy Design Lead During Construction. Outside of work, Jake enjoys hiking, watching soccer, and touring the city’s playgrounds with his two young children.
Dinner Meeting Cost:
Students: $40
SEAW Member: $65
ASCE Member: $65
Non-Member: $75
Registration closes at 12pmPT on April 27, 2026.
