Breaking down East Link Starter Line ridership

East Link Starter Line map, by Sound Transit

Now that Sound Transit has paved the way for an East Link Starter Line (ELSL) opening for next Spring, it's worth deep diving into the projected ridership numbers. At the last Sound Transit Board meeting, early ridership estimates were pegged at a modest 6,000 average weekday boardings, reflecting limited demand until the 2-Line is fully connected to the main 1-Line spine via I-90.

The ELSL, which will run between South Bellevue and Redmond Technology Station, is not directly served by any single bus route currently. Rather, its sub-segments are served by various disparate routes that are a hodgepodge of local and express service:

• Between South Bellevue & Downtown Bellevue: 550/556 (Bellevue Way), 241 (108th), 249 (Enatai)
• Between Downtown Bellevue and Overlake Village: 226 (Bel-Red Rd), 249 (Northup, NE 20th), B-Line (NE 8th, 156th Ave NE)
• Between Downtown Bellevue and Redmond Technology Station: B-Line, 566

The ELSL does serve some existing commuter markets, namely the two corridors between South Bellevue, Downtown Bellevue, and Redmond Technology Station (Microsoft). But it is also serving entirely new markets that are difficult to forecast given the rise of remote work, lack of connection to the 1-Line, and absence of any single precursor service. More on each ELSL sub-segment below the fold.

South Bellevue - Downtown Bellevue

Between South Bellevue Station and the Bellevue Transit Center, riders currently have the option of 1) taking the frequent 550 or peak-only 556 via Bellevue Way, 2) the 249 hourly milk run through Enatai, or 3) the 241 via 108th Ave NE. Presumably, the latter two routes will continue to provide infrequent local services without much ridership loss from ELSL service.

As things currently stand, Sound Transit is not planning to make any routing changes to either the 550 or 556. I expect the main South Bellevue-Downtown market will likely move to the ELSL, although this is a very small ridership base. Sound Transit has not published any recent stop-level ridership, but based on the 550 profile from the 2020 Service Implementation Plan (p. 134), only a small fraction of the route's riders consists of intra-Bellevue trips.

It's also worth mentioning that the ELSL will not be a full replacement for those traveling to and from the western half of Downtown Bellevue, currently served by stops on Bellevue Way at Main Street and NE 4th. These are outside reasonable walking distance of the Bellevue Downtown Link station, which is even farther east than where the Bellevue TC currently sits.

One net new market being created is the area served by East Main Station at 112th Ave NE and Main St. The station area is currently a mix of low-density single-family homes to the southwest, office uses with large setbacks to the east, and medium-rise apartments to the northwest. Although East Main is being actively targeted for TOD, this is a far-off reality and its ridership in the near-term will likely be rather limited.

Bel-Red Corridor

Currently, the Bel-Red corridor is served by the 226 at the southern boundary (along Bel-Red Road), which operates 30-minute headways during the weekday. The north end is buttressed by the 249, which crawls through Overlake and Northeast Bellevue (via Northup Way and NE 20th) on its way to Microsoft.

Neither route is very productive: the 249 sees just about 500 average weekdays boardings, while the 226 serves just north of 1,000. With a longer service span and higher frequency, the ELSL might poach some of these riders in addition to gaining new ones, as the existing stop pairs closest to the 120th and 130th stations are all within walking distance of Link. These riders would likely be commuters traveling to and from businesses in the Bel-Red area or Spring District residents who work either in Downtown Bellevue or at Microsoft.

The biggest factor that might be limiting ridership is simply that the area is not built up very much yet. Despite Bellevue's grand plans to upzone the entire Bel-Red corridor, most of the existing land use is still light industrial. The Spring District, centered around the 120th, is about half built, but much of its future success depends on how much office space Meta can commit to in the long-term. A few other TOD projects dot the landscape around the 130th station but they are few and far in between.

Overlake & Redmond Technology Station

The Overlake Village and Redmond Technology stations are the two primary Microsoft-serving stations, although the latter is currently much better connected regionally via existing express routes.

The Overlake Village area, on the other hand, is not as well served by existing transit service, but envisioned for TOD growth. Similar to East Main and Bel-Red, however, the area is only partially built out. Ergo, near-term ridership on the ELSL is likely to be generated from existing commuting patterns to and from Downtown Bellevue or Microsoft. These origin-destination pairs are already served by the B-Line, albeit with much slower travel times.

Origin	Destination	Route	Travel Time
Downtown Bellevue	Overlake Village	B-Line	~20-25 min
Downtown Bellevue	Overlake Village	2-Line	9 min
Downtown Bellevue	Redmond Technology Station	B-Line	~25-30 min
Downtown Bellevue	Redmond Technology Station	566 (peak-direction only)	~10-20 min
Downtown Bellevue	Redmond Technology Station	2-Line	10 min

Existing transit travel times compared to Link

Given that the rest of the B-Line functions more as a local service to connect Crossroads to both downtown and Overlake/Microsoft, I don't anticipate substantial shifts in ridership even after the ELSL opens. With its congestion-free operation, East Link is likely to be much more competitive with the longer-distance Bellevue-Redmond commuter markets.

Concluding Thoughts

Although I don't have insight into the ridership model that is projecting the 6,000 average weekday figure, there simply isn't very much existing transit ridership in the ELSL service area. I suspect that a fair share of the demand will be induced by the sudden windfall of fast frequent rapid transit, the likes of which have never been seen before on the Eastside.

The more cynical take is that ridership growth will continue to be stymied by two main factors: the abundance of free parking on the Eastside and slow progress in TOD development. Neither of these can be changed overnight, but the mere start of Link service might be enough of a catalyst to help move things along.