Under a full moon and the gaze of giddy rail fans, Sound Transit accomplished a necessary feat overnight by running an electric-powered railcar across the I-90 floating bridge.
The first trip, from the Eastside to Seattle, chugged along at walking speed. Then the car reversed direction on the Seattle side and traveled back to Mercer Island at low speed. After that, the team planned to reach 20, 30, 40 and then mph cruising speeds, but that might require a follow-up shift Tuesday night, according to Tony Raben, executive project director.
Those trial runs kick off a season of tests and practice trips, before the public can finally ride across Lake Washington between Bellevue and Seattle, a milestone aimed at early 2026. Those trains, known as the 2 Line, will then travel all the way from Redmond to Lynnwood, sharing track in North Seattle with the older 1 Line.
The lake crossing is expected to not only transform transit in the region, it will make history as the world's first light rail system to run on a floating bridge.
Three dozen supporters brought cameras and pizza to witness that history, the vibe similar to Blue Angels fans at Seafair who show up in Seattle's East Portal Park, which perches over the west lakeshore and freeway.
At nearly the same moment the railcar first entered the I-90 bridge from the Mercer Island side, 11:49 p.m., a thick shower of sparks streaked high above the park, from an apparent meteor.
The little train that could!" a witness shouted several minutes later, when the Siemens-brand railcar arrived and vanished into the Mount Baker Tunnel. Applause broke out. Transit-board member Claudia Balducci of Bellevue received a double high-five. "It's surprisingly exciting, for a 10 mph train trip," she said.
Construction has been plagued by problems that have delayed by almost three years the 2023 expected start of service.
Monday night's trips were devised partly to demonstrate that Sound Transit can control stray current, which might otherwise penetrate the concrete track ties and highway decks, corroding steel rebar. That in turn would weaken the bridge pontoons over decades, and jeopardize the Washington State Department of Transportation's plan for the Homer Hadley Bridge, built in 1989, to last another 75 years.
Among other nuances, transit engineers kept the trackway dark, the better to measure any electric arcing between the overhead power lines and the railcar. The first trip showed no virtually no arcing, a good sign that "everything was smooth, said Sound Transit spokesperson Henry Bendon.
Commuters and politicians have dreamed of trains over the lake since at least 1970, when the corridor appeared in the Forward Thrust series of public-works ballot measures, but failed to pass.
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