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Sound Transit Board identifies preferred alternative site for Operations and Maintenance Facility South

Facility is needed to store, clean and maintain expanding light rail fleet

Publish Date

The Sound Transit Board today identified South 336th Street in Federal Way as the preferred alternative to study for a new Operations and Maintenance Facility (OMF) South located in South King County. An OMF is where light rail trains go for cleaning, storage and maintenance. To keep its entire light rail system functioning, Sound Transit needs to strategically locate OMFs that operate 24 hours a day, year-round.

The Board weighed community priorities, input from Native American tribes, agencies and cities as well as a technical study consisting of more than three years of analysis. The OMF South will serve Sound Transit’s growing light rail fleet as the agency continues to expand congestion-free light rail across the region. The facility will generate approximately 470 full-time living wage, union-supported jobs.

"Having been in the trenches when we sited the Operation and Maintenance Facility East in Bellevue, I know these decisions are never easy," King County Council Chair and Sound Transit System Expansion Committee Chair Claudia Balducci said. "Reaching agreement on the South 336th Street Alternative required a lot of detailed technical work and analysis from staff, substantive engagement with neighbors and other stakeholders, and diligent deliberation by Boardmembers, especially those members of the System Expansion Committee.  I’m glad we found a solution that fulfills the project goals while balancing the impacts to the surrounding community."

In May 2019, the Sound Transit Board identified three sites to be studied in the Draft Environmental Impact Statement (DEIS) for OMF South:

  • Midway Landfill and Interstate 5 (I-5) – The site is located south of South 246th Street, west of and adjacent to I-5 and sits mostly on a former superfund landfill site. 
  • South 336th Street and I-5 – The site is located in the City of Federal Way, west of I-5 and south of South 336th Street. 
  • South 344th Street and I-5 – The site is located in the City of Federal Way, west of I-5 and north of South 344th Street. 

This is not a final decision on the site for the OMF South facility. The preferred alternative site at South 336th Street will now be studied, along with the two alternative sites as part of the Final Environmental Impact Statement (FEIS) scheduled for publication in 2022. In the FEIS, Sound Transit will respond to substantive comments provided by the public, Native American tribes, agencies and cities received during the DEIS comment period.

Following issuance of the FEIS, the Board is expected to select the project to be built in late 2022. Final design, construction and testing of the facility are scheduled to take place from late 2024 – 2028, with the new facility opening in 2029. 

Sound Transit currently operates one OMF in Seattle and another facility in Bellevue. In addition to studying potential locations for an OMF in South King County, the agency will also require a new OMF in Sound Transit’s North Corridor.

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