Sounder South Capacity Expansion

Improvements to serve more Sounder South riders
Sounder South Capacity Expansion web photo

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Ridership on Sounder South has increased steadily, and this is expected to continue as the region grows. To help meet growing demand, in 2016 voters approved the Sounder South Capacity Expansion program and an extension to DuPont. The goal of the program is to expand Sounder capacity and improve rider experience.

Improvements could include:

  • Longer trains.
  • Additional weekday trips.

Any additional service would require negotiation with BNSF, the railroad that owns most of the tracks used by Sounder.

The first step of the capacity expansion program is creation of a strategic plan to identify projects, service and completion dates. Planning for program elements is expected to begin in 2020. This includes:

  • Platform extensions to accommodate longer trains 
  • Purchasing rail cars
  • BNSF negotiations 
  • King Street Station platform improvements 

Projects will be completed on a rolling basis, with all complete by 2036.