The start of work marks the end of nearly a decade of planning and preparation. A federal grant is set to meet $US 1.17bn of the project’s $US 2.9bn cost, the largest single appropriation by the Trump administration towards an infrastructure project. The project is also supported by a $US 658m low-interest loan from the US Department of Transportation’s Build America Bureau.

The Stacy & Witbeck-Kiewit-Hoffman (SKH) joint venture and the Skanska L300 joint venture of Skanska USA Civil West California District and Skanska USA Buildings were awarded respective $US 789.4m and $US 817m contracts for construction on the project last month.

The Skansa contract includes construction of more than 3.2km of elevated alignment and 2.4km of at-grade infrastructure as well as two stations, a park-and-ride garage, track and associated infrastructure. The contract includes a $US 38.9m contingency and following preparation work, takes the value of the joint venture’s work on the project to $US 878m. The SKH joint venture is similarly responsible for 2.4km of elevated structures, 4.8km of at-grade alignment, the remaining two stations and two park-and-ride garages. It also has a $US 37.6m contingency and the total value of its work including pre-construction activities is $US 883.8m.

Services on the new line are scheduled to begin in 2024 and Sound Transit plans to operate a train every four-six minutes during weekday peak hours. S70 LRVs on order from Siemens will operate the new service.

The line is expected to carry 47,000-55,000 daily passengers by 2026 and is estimated to eliminate 160 million vehicle miles on the congested Interstate-5 highway.

“From the beginning, this project has received enthusiastic support from the federal, state and local governments, our congressional delegation, the business and labour communities, and voters - a sign of the hunger for relief from the horrendous highway congestion facing travellers every day,” says Mr Peter Rogoff, Sound Transit CEO. “This project will be a game changer for Snohomish County commuters. And in the years to come, we will be extending Link from Lynnwood all the way to Everett.”

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