Sound Transit prepares to launch first Northgate Link tunnel boring machine

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TBM dedicated as crews get ready to move it into position for June launch

As crews prepare to move the first Northgate Link light rail tunnel boring machine into launch position, officials today gathered for a dedication ceremony, smashing a bottle of Washington cider on its 21-foot cutter head. 

"This project will cut through some of the worst traffic in the state, creating the capacity to move up to 800 riders in each direction every few minutes with zero congestion," said Sound Transit Board Chair and King County Executive Dow Constantine. "It will immeasurably improve the lives of its riders. It will also prove critical to the functioning of I-5 as the region's population grows approximately 30 percent in the next two decades."

The machine, which between 2011 and 2012 successfully completed two one-mile tunnels for the University Link light rail project, is one of three tunnel boring machines (TBMs) that will help extend light rail 4.3 miles further north. The University Link light rail project is currently scheduled to open in the first quarter of 2016, six to nine months early, and is more than $100 million under budget.
The $2.1 billion Northgate Link Extension, which will open in 2021, will run mostly underground through one of the most congested travel corridors in the region and includes underground stations serving the U District and Roosevelt and an elevated station at Northgate. The line will add major new capacity to the region's transportation system, offering fast, frequent and congestion-free service 20 hours a day. A trip from Northgate to downtown will take 14 minutes. Northgate to UW Station will take eight minutes. 

The tunneling contractor is now finalizing the TBM assembly before moving it into launch position to complete final safety and operational checklists. The TBM weighs over 1 million pounds and stretches more than 300 feet long including the conveyor systems that remove the spoils. Sophisticated satellite technology guides the machine.

The machine that was dedicated today proved reliable in mining the twin one-mile light rail tunnels between Seattle's Capitol Hill and downtown areas on schedule. The same contractor team that completed those tunnels, a joint venture of Jay Dee Contractors of Livonia, Mich., Frank Coluccio Construction Company of Seattle, and Michaels Corporation of Brownsville, Wis., won the contract for the Northgate Link tunneling work with a proposal that was 25 percent below the engineer's estimate.

Over the past 13 years, Sound Transit's current administration and Board leadership have maintained an outstanding track record delivering major infrastructure projects. In 2009, the agency opened the region's initial light rail segment within the budget and schedule that were established in 2001. In addition to the upcoming completion of University Link ahead of schedule and under budget, Sound Transit remains on track to deliver more than 30 miles of further light rail expansions by 2023 despite a cumulative revenue reduction of 29 percent caused by the national recession.

In 2016 Sound Transit will launch the construction of East Link light rail from downtown Seattle to Mercer Island, Bellevue and Redmond's Overlake area. Planning and environmental work are moving forward to establish alignments for extending light rail from Northgate to Lynnwood and from South 200th Street to the Kent/Des Moines area. Following the 2023 opening of all the Sound Transit 2 extensions that regional voters approved in 2008, Link trains are projected to carry more than 280,000 riders each weekday by 2030. The projects are playing a major role in the region's ongoing recession recovery, creating a projected 100,000 direct and indirect jobs.

The region's 50 miles of light rail will serve as a critical element of the region's overall transportation system, significantly expanding its capacity and attracting riders who won't compete for increasingly scarce space on congested freeways and roads. In 2012 alone, the average Puget Sound resident spent 33 hours stuck in traffic. As growth continues, commuters could spend 300 percent more time sitting in traffic according to Puget Sound Regional Council projections. 

More information on the Northgate Link Extension