Connection Points

Seattle's bus network used to be focused on bringing people to work downtown. As our city grew, it spread its wings across First Hill, Capitol Hill, Fremont, and the Eastside. Though Amazon was earlier in the middle of downtown, it now occupies South Lake Union (SLU) and Bellevue. While a one-seat bus ride to downtown used to be the norm, once you have more destinations to cover, it becomes more important to develop a network of interconnecting lines. Besides the frequency on the lines, the connecting points between the lines determine how easy or time-consuming the transfer is. We built transit centers to help connect lines. With light rail construction, most stations also became places where multiple bus lines would intersect. Mount Baker Station is a good example where transfers could be much better if the buses would serve the Link station more directly instead of having to walk and cross a busy road.

SODO center platform rendering (by author over Google Maps)

While we currently only have a single light rail line, soon the 2 Line will share tracks and stations with the 1 Line in North Seattle. If you want to travel from Bellevue to the Rainier Valley, you will have to transfer at the CID Station. You will need to go up to street level, walk across and down again to the other platform. A center platform would make this much easier. In fact, when Sound Transit had to single-track the tunnel and force a transfer at Pioneer Square Station a few years ago, they added a temporary center platform to make it easier for riders to transfer from one train to the next one on the other track. Unfortunately, they removed it after construction was done. I wish Sound Transit would add a center platform at the CID Station as they had considered a while back. With an exit escalator on one side of the platform and an elevator on the other, people could not only do a cross-platform transfer, but also board more quickly in Spanish style: new riders could enter from the outside, while riders could exit via the center platform.

The current design for the West Seattle light rail extension (WSLE) calls for a new separate set of tracks through SODO to be built where buses have an exclusive busway south of downtown. Besides forcing those buses to use I-5, it will force all riders from (and to) West Seattle to go up an escalator or elevator, cross over the track, and go down an escalator/elevator until the tracks get extended towards downtown. While this makes operation and construction easier, the rider experience will suffer in particular for riders with mobility challenges or when escalators fail. I don't understand why Sound Transit has not (at least publicly) considered alternatives which are used by other agencies: Instead of locating the new tracks to the west, the new tracks could be located on both sides of the existing tracks, turning the existing side platforms into center platforms between the old and the new tracks. Then riders who want to continue in the same direction could just walk across the platform to transfer. Only riders who want go in the opposite direction, such as from West Seattle to the airport, would need to use the escalators/elevators. Yes, construction would be more complicated because the new east track would have to cross under the Rainier Valley line overpass and, further north, over or under the tracks before entering the new downtown tunnel. But it would accelerate transfers and make the ride far easier if you have mobility challenges.

Another alternative would be for the West Seattle line to use the existing SODO tracks instead of building a new set of tracks. Again, the new east track would need to go under the existing Rainier Valley overpass before merging with the existing track right before the SODO station. It would allow riders to step off one train, wait for the next one from the other line, and continue. If a center platform would be added, riders who want to continue in the opposite direction could just cross the platform to transfer. A single set of tracks could handle enough trains in the foreseeable future. While operation would be slightly more complicated, it may be possible to keep the bus lane and the station would be far smaller and less expensive to build. It would even allow West Seattle trains to continue towards Northgate and increase frequency on the crucial downtown-to-UW portion well before the second downtown tunnel gets built. For many West Seattle riders, that would eliminate the need to transfer. If a second downtown tunnel would be built, the tracks could be split off between SODO and Stadium Station.

The plan to build a second downtown tunnel and redirect Rainier Valley trains through that tunnel to Ballard to form the new 1 Line will further complicate transit in Seattle and force more transfers and make some of them more arduous. With the current plan of a North CID and a South CID station, many Rainier Valley residents will have to walk further to their destinations in the CID or downtown. They may want to consider transferring at the SODO station. Optimizing the SODO transfer would help tremendously. If you want to take Link to catch a flight from Bellevue, you have to take your luggage up to street level at the CID and carry it to the South CID, or continue to Pioneer Square and meander through the escalators and tunnels which will lead you to the North CID station. Or you might as well continue to Westlake where the transfer might be easier but that may add 15 minutes to your travel. Lots of tradeoffs.

However, if we just keep the 1 Line in the current tunnel together with the 2 and 3 Line and keep Ballard separate, we would not only get higher frequency downtown, but then riders could just step off the train and wait for the next one at any of the downtown stations. That would reduce congestion at CID and Westlake. With a center platform at the CID, riders to/from Bellevue, West Seattle, or Rainier Valley could just cross the platform to travel in the opposite direction. Riders to/from Ballard could just take a single escalator to reach any of the other lines.

As Reece (aka RMTransit) pointed out in a recent video, connection points or junction stations are the most important points of a transit system and crucial to the rider experience. Sound Transit has started to publish some transfer time estimates, but they all assume that riders are familiar with the connections and do not have any mobility challenges. Larger subway systems even build two transfer stations next to each other where lines merge to allow cross-platform transfers in one vs another direction. Dow Constantine keeps bragging about how many jobs ST3 has generated. I wish all their work would have a greater impact on the experience of transit riders.