LOCAL NEWS
Concrete supports need to be rebuilt, delaying Eastside light rail
Apr 14, 2023, 11:13 AM | Updated: Apr 17, 2023, 1:13 pm

The Interstate 90 bridge construction (Photo from Sound Transit)
(Photo from Sound Transit)
Bad concrete and a failed fix to the supports that hold up the rails have forced the lengthy delay in construction on Interstate 90 (I-90), and Sound Transit doesn’t expect to open light rail across Lake Washington until late 2025.
This delay was caused by mortar failures in the 5,455 concrete supports on the bridge and has forced a complete restart of plinth construction.
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In an interview with KIRO Newsradio’s Chris Sullivan, Sound Transit CEO Julie Timm said more than 75% of the faulty supports have been replaced while the replacement supports have been approved and the installation process is underway.
“About 75%, plus or minus, have been taken out. We have the new ones. It took a while for us to make sure the engineering, training, and construction to do an inspection were all lined up to our satisfaction. It was recently approved,” Timm said. “Now we’re seeing how fast they can put them up. And once we see how fast they can put them up and maintain that quality, then we’ll know what is going to get done.”
This has forced Sound Transit to delay its Eastside Link, which will add 14 miles of new track and 10 new stations, with an original opening date of 2023 to spring 2025.
“Right now, we’re targeting to schedule so that we’ll be able to open that section of light rail in 2025, which is very painfully far away,” Timm said. “I get that, and we’re doing everything. We can do it faster, but we don’t want to compromise that quality,”
The agency is now looking into opening an Eastside-only “starter line” between Bellevue and Redmond in 2024, a year before it connects to Seattle. Sound Transit plans to open Bellevue to Redmond service in about a year.
Sound Transit Board’s System Expansion Committee was informed of the delay in a meeting in August, with problems like complications from the COVID-19 pandemic, the concrete workers’ strike, and unexpected problems with the mortar pads, rebar, and fasteners.
“It’s frustrating to take an extra year, an extra two years to design it right to understand what we’re doing, but it’s needed,” Timm said. “It really is needed, and as the environment has changed as our society has changed from what it was three years ago, pre-pandemic, to now, it puts a different lens on the decisions that we’re making and how we’re serving our community, how we’re connecting people.”
When completed, Sound Transit said passengers would be able to utilize “almost 40 miles of fast, reliable light rail, from the Eastside to downtown Seattle and Northgate and to Sea-Tac Airport and Angle Lake.”
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Timm empathized with everyone looking forward to the Eastside expansion but emphasized the importance of getting the groundwork done right to prevent future problems.
“I would say that same frustration is shared inside the agency. We all feel the same way. We want to get it built. We want to be using it. We want to extend. We want to make sure we’re connecting up to Snohomish and down to Tacoma,” Timm said. “We want to get the spine built out. You will find no lack of that desire inside this agency either. And yet, as we build it, whatever it is that we build will be here for 50 to 100 years. It is the groundwork, the framework for all the mobility that we’re going to be building in the future.”
Chris Sullivan contributed to this report