Operations and Maintenance Facility South

Maintaining the growing light rail fleet.
Project map for Operations and Maintenance Facility South project


A new Operations and Maintenance Facility is needed in the South Sound to receive, store and service a larger train fleet to support future light rail extensions to Tacoma, West Seattle and throughout the region.

An OMF is where light rail trains go 24 hours a day, 365 days a year for cleaning and care. To build this new facility, we need approximately 60-70 acres (for reference, one football field is 1.3 acres) near an operating light rail line.

As part of system expansion plans, we need a total of four OMFs across the region. In addition to this future facility in South King County, we currently service the existing light rail fleet at a central OMF on South Forest Street in Seattle. We've built a second facility in Bellevue and will also add another OMF north of Seattle. 

Benefits of the OMF South

  • Creates high-skilled, living-wage jobs for more than 470 people in South King County. At our existing OMF Central in Seattle, the average employee wage is more than $40 per hour, or $80,000/year.
  • Ensures thousands of passengers ride clean, well-maintained trains. We suspend service every night between 1-5 a.m. so we can properly service our Link trains.

Current project status

On Dec. 16, 2021, the Sound Transit Board identified the South 336th Street site as the preferred alternative for the location of the OMF South.

The Board’s identification of a preferred alternative is not a final decision. This action indicates where the Board is leaning in their decision-making, based on the findings in the Draft Environmental Impact Statement and comments submitted by tribes, agencies and the public during the Draft EIS public comment period.

We are in the middle of an environmental review process, and we’ll continue to study the South 336th Street preferred alternative, along with the two other sites (Midway Landfill Alternative and South 344th Street Alternative), in the Final EIS. After we issue the Final EIS in late 2022, the Board will select the project to be built.

Have any additional questions or comments? We're always here to help. You can contact the project team at omfsouth@soundtransit.org.

We encourage you to sign up for project email updates for all the latest news as OMF South develops.

What can I expect as a project neighbor?

  • If you're a resident or a business or property owner near a potential OMF South site, signing up for email updates is the first step to ensuring you're always up to speed on the project. If you have any questions or you'd like to set up a meeting to learn more, contact the project team at omfsouth@soundtransit.org.
  • The Draft EIS evaluated possible property impacts in detail. We hosted a formal comment period on the Draft EIS from March 5 to April 19, 2021. In the Final EIS, we’ll further study the site alternatives and will respond to substantive comments received from the Draft EIS.
  • The Sound Transit Board will make a final decision on the site and the project to be built after we issue the Final EIS in late 2022.