The Sound Transit Board of Directors on Thursday selected Kiewit Infrastructure West Co., to design and build the Federal Way Link Extension.

The project will extend regional light rail 7.8 miles from the Angle Lake station in SeaTac through Kent to Federal Way. Three new stations will be built in Kent/Des Moines near Highline College, at South 272nd Street and at the Federal Way Transit Center. The total amount of the contract with contingency funding is $1.4 billion.

A Sound Transit committee recommended on May 9 that the full 18-member board select Kiewit.

“The addition of light rail to Federal Way will give South King County residents a much-needed transit option,” said Pete von Reichbauer, King County Councilmember and Sound Transit Boardmember, in a Sound Transit news release. “The Federal Way Link Extension is a long-awaited addition to our region that encourages employers to look beyond the downtown Seattle area and will transform the way we travel for work and leisure activities.”

“South King County residents are one-step closer to fast and accessible light rail service, “said Peter Rogoff, Sound Transit CEO. “Building this project is the culmination of years of patience by South King County residents and collaborative work with the cities of SeaTac, Kent, Des Moines and Federal Way. We also have a great partnership with WSDOT to use much of their right-of-way along I-5 to build this line.”

The design-build contract includes all work to complete final design and construction of the light rail guideway which will connect to the existing Angle Lake station in SeaTac and extend south along the west side of I-5 to the Federal Way Transit Center. Kiewit will also complete final design and construction of three new light rail stations, three parking garages, the overhead catenary system, traction power substations, train control and communications, special track work, utilities and street improvements.

Sound Transit is working closely with the Washington State Department of Transportation (WSDOT) on the State Route 509 Completion Project. As part of a partnership agreement, Kiewit will build a new bridge over State Route 99 near 208th Street in the City of SeaTac as part of the first stage of the SR 509 project. Since both projects are being constructed in the same area, this joint effort will reduce impacts to the community.

It is anticipated that early demolition and utility relocation work will begin later this year.

Major civil construction activities are expected to begin in 2020. Service on the new regional light rail extension is schedule to begin in 2024.

The Federal Way Link Extension is seeking a grant from the Federal Transit Administration’s (FTA) Capital Investment Grant (CIG) program that will fund approximately 25 percent of the project. The CIG program is the federal government’s primary financial resource for supporting transit capital projects that are locally planned, implemented and operated. The project recently received Entry into Engineering approval from the FTA, clearing a major milestone in the grant application process.

The project is in line for the final of four loans from the Transportation Infrastructure Finance and Innovation Act (TIFIA). Sound Transit become the first transportation agency in the country in 2016 to enter into a master credit agreement with the U.S. Department of Transportation that will provide $2 billion in low-interest loans spanning four projects. The loans, enabled by the USDOT’s Build America Bureau TIFIA, are cumulatively forecasted to save regional taxpayers between $200 million and $300 million through lower interest costs.