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ST3 Plan and project list

On Nov. 8, 2016, voters of the Central Puget Sound region approved the Sound Transit 3 (ST3) ballot measure. The plan builds 62 new miles of light rail to form a 116-mile system.  ST3 extends the Sounder south rail line by two stations at Tillicum and DuPont while extending station platforms and making other improvements to expand passenger capacity along the entire south line. Bus rapid transit is built to serve communities north, east and south of Lake Washington and parking and access improvements are made to stations throughout the region. 

ST3 Plan

The following documents provide detailed descriptions of individual projects included in the ST3 Plan. 

Central Corridor Projects

East Corridor Projects

North Corridor Projects

South Corridor Projects

Bus Reliability Projects

All other projects

Sound Transit developed a conceptual scope of work for these projects for the purpose of generating a representative range of costs, both capital and operating; and benefits, including ridership forecasts, TOD potential, multi-modal access and others. Final decisions on project elements (e.g., alignment, profile, station locations, and number of parking stalls) will be determined after completion of project level environmental review, and preliminary engineering during which opportunities for public participation will be provided. Therefore, this scope definition should not be construed as a commitment that all representative features will be included in the final developed project.

For additional ST3 documents, see also: ST3 Plan development archive