Just before midnight on Monday night, I was standing on the I-90 pedestrian walkway with six other people and one nervous-looking shiba inu. The sky was clear and the moon was full, so Lake Washington was bright. Traffic would have felt sparse if you were in a car, but on foot, it felt like a crowded jet way. All seven of us were watching the other end of the bridge—most of us were squinting at the tracks between the east-bound and west-bound roadways; one older man with a baseball cap and a windbreaker periodically picked up his binoculars and peered toward Mercer Island.
At 11:53 p.m., headlights appeared just above the empty tracks. Then some orange lights came into view. And finally, a whole light rail car, moving slowly enough across the bridge that men with hard hats and hi-vis vests could keep up, but just fast enough that they had to run.
The train was manned by about a dozen workers, also in hi-vis vests and hard hats, looking like late-night commuters.
That light rail car was the first to ever cross a floating bridge using its own power, and it’s a huge milestone actually connecting the 1 and 2 lines, and turning our amusement ride of a train system into public transit. Before Monday night, the closest Sound Transit had come to getting a train car across the bridge was when they towed a car across last May.
Sound Transit has been trying to figure out if this slow-motion feat was possible since 2005, when engineers sent trucks carrying 600 ton loads across the bridge to make sure it wouldn’t collapse under the weight of the trains. Next, Sound Transit will start months practice trips, before they open the I-90 crossing in spring 2026.