New Alternatives for the Tacoma Dome Link Extension

Option for Tacoma Dome Station

While West Seattle and Ballard (and Eastside BRT!) have been getting all the media attention, Sound Transit continues to refine Tacoma Dome Link extension, a 4 station, ~10 mile connection that will complete the southern end of the light rail spine by 2030.

The Tacoma Dome Link extension is not to be confused with the extension of Tacoma Links, the streetcar operated by Sound Transit through Downtown Tacoma. ST even includes a little diagram in case you get confused:

Sound Transit has provided a wide array of options, which as always carry a similar set of tradeoffs: car access vs. bus transfers, TOD opportunities vs. business impacts, ridership vs. capital costs. Sometimes the geography presents a win-win, other times hard decisions must be made.

Compared to Lynnwood and Federal Way, the I-5 vs. 99 tradeoffs are minor. South Federal Way station is the exception.

Unlike in (some of!) Seattle, the walkshed around these stations is supremely car-oriented today. The goal ought to be to maximize opportunities for transit-oriented redevelopment in the station area while minimizing the number of immovable obstacles (interstate highways, bodies of water, freight tracks, etc.).

Let's have a look at the latest options, starting at the Tacoma Dome station (visualizations PDF), so as not to be so Seattle-centric in our thinking.

ST finds greater advantage in a station on E 25th St (TD2 & TD3). This location provides the best multimodal access and connection to Tacoma Link, Amtrak and Sounder.

TD1 has good ridership but more business impacts. TD2 has more potential property impacts and is more expensive to build, but closer to Sounder and Tacoma Link connections. TD3 is currently constrained by zoning, but that's fixable. TD4 would terminate the line in the Tacoma Dome parking lot.

Less than a mile up the road is East Tacoma station (visualizations). Bisected by I-5, the East Tacoma station area has industrial uses on one side and single-family residential on the other. Intersecting freeways, trains and rivers makes any station choice a challenge.

ST's sole preferred option for East Tacoma (3A) comes at the highest cost but makes the best use of the walk shed for pedestrian and other non-motorized access.

Heading north, the trains would stop next in Fife (visualizations), where all alternatives are on or around SR-99 (just a block from I-5). ST finds the highest potential for a station one block off Pacific Highway on 15th Street E (3A/3B). There are some conflicts with "view-dependent businesses" for the I-5 alignment and higher costs for routing via 99.

Finally, we arrive in South Federal Way (visualizations), a suburban area with mostly car-oriented businesses but lots of potential for TOD. Here we see the classic I-5 vs. SR-99 battle most clearly. I-5 (SF8/9) would emphasize car access to the station, while a station on SR-99 (SF4) would have the most development potential (but with higher costs and impacts to existing businesses). SF2 splits the difference and puts the station on Enchanted Parkway.

You can comment online between now and May 1.