Sound Transit began light rail testing on the I-90 floating bridge in Seattle Wednesday.
The unpowered car was pulled from the Mercer Island station to the Judkins Park station.
Sound Transit says it’s the first phase of integration testing.
“This floating bridge segment represents one of the most challenging and unique aspects of this complex mega-project,” a news release from the agency states.
It will be the first light rail to run across a floating bridge.
During final rail installation, where the tracks are anchored to the concrete support blocks below them, crews found that a small number of the bolt inserts within the blocks need replacement.
“While not concerning based on what we know today, we want to get those connectors replaced now,” the release says.
Sound Transit also wants to make sure that bringing the electrified light rail across the bridge won’t damage its existing structure.
Testing is expected to last through the summer.
“Above all, we’re going to take the time to get it right,” Sound Transit says.
The agency is expecting to fully open the line over Lake Washington next year before the FIFA World Cup.
Thursday’s test run comes just 11 days after the opening of the extension into downtown Redmond.
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