East Link E330 - Downtown Bellevue Tunnel

Bellevue, Washington
Sound Transit
H-J-H Final Design Partners
Contract Value: 
2,000 Linear Feet
Year Completed: 
The Atkinson team will demolish existing structures to make way for an underground light-rail tunnel in downtown Bellevue, WA. This is Atkinson's second contract award is of the 12 projects that will complete the East Link Extension. Atkinson, in a joint venture with Stacy and Witbeck, was awarded the first phase of the project – the E335 Contract – in early 2015. 
Construction will begin with the south portal of the Downtown Bellevue Tunnel near 112th Avenue and Main Street. The tunnel will continue under the 110th Avenue NE for approximately one-half mile, then turn east near NE 6th Street towards the north portal, which is adjacent to Bellevue City Hall and the Bellevue Transit Center. 
The team also will perform grading and utility relocation, and install temporary sound walls, retaining walls, and a portal box structure at the south portal. The scope also includes 585 linear feet of soil nail wall support of excavation and 325 linear feet of permanent soil nail wall system. The tunneling operation includes approximately 1,985 feet of Sequential Excavation Method tunnel construction, as well as tunnel pre-support, ground water control, waterproofing, final lining, tunnel walkway, center dividing wall, embeds and conduits, and a mid-tunnel access shaft and adit work.
Once the tunnel is complete, Atkinson will construct the north portal, track, and additional tunnel appurtenances as part of our overlapping E335 Downtown Bellevue to Spring District contract.
Construction is underway and substantial completion is scheduled for July 2020.