On the 19th of August Sound Transit announced that Atkinson Construction had completed the civil construction of the Bellevue tunnel. The tunnel will connect the East Main and Bellevue Downtown stations in Seattle, when East Link begins operating in 2023. Excavation of the 605 m (1985 feet) tunnel began in 2017. Using a process known as the sequential excavation method (SEM), crews employed conventional equipment including track-mounted excavators and cutting equipment to remove soil in small sections and support excavated areas with spray-applied concrete. Crews then applied waterproofing and constructed the centre wall and final concrete lining.
Stacy and Witbeck/Atkinson, the stations contractor for the segment of East Link that runs from downtown Bellevue to the Spring District, is continuing to install track inside the tunnel. The East Link will extend light rail 22.53 km (14 miles) from downtown Seattle to downtown Bellevue and the Overlake area of Redmond via I-90, with 10 stations. Following the 2023 opening of the project, in 2024 Link light rail will then extend another 5.47 km (3.4 miles) east to new stations in Southeast Redmond and downtown Redmond. Click here for a video of the full construction process, here and us/42 for the tunnelbuilder archive. Visit https://www.soundtransit.org. 34/20.
