If voters in Pierce, King and Snohomish counties approve the Sound Transit 3 ballot measure, they would approve an expansion of not only the light rail system but also the Sounder commuter rail.
Sounder trains share the track with freight and Amtrak trains, which is partly why they can't run in both directions all day. The two Sounder lines together see an average of more than 16,000 riders a day.
Right now, the North Line runs from Everett to Seattle a few times in the morning and then in the opposite direction in the evening. The South Line between Lakewood and Seattle runs on a similar schedule, but more frequently.
Under ST3, the South Line would be extended to Tillicum and DuPont to serve Joint Base Lewis-McChord. Sound Transit also wants to extend platforms along this line. They would accommodate 10-car trains to carry more people than the 7-car trains do now.
South Line riders waiting for a train home at King Street Station said they liked having the option to avoid highway gridlock. They said having access to regional transit, not just in-city transit, meant they could take jobs that are farther away from home.
While South Line commuters have been asking for more runs and more space, they've also been asking for more parking. ST3 includes plans for parking for the North Line stations, but does not explicitly plan for parking along the South Line.
This is Part IV of our series Sound Transit 3: The $54 Billion Question.