Sound Transit has an under-appreciated opportunity to build a world-class BRT on the Eastside.
Train service faces well-known geometric challenges in East King. Cities are not linearly aligned, so high quality rail service means many rail lines. But the Eastside urban centers are mostly much smaller than potential stations in Seattle, requiring large investments in either feeder bus service or park-and-rides. Either way, conspicuously high costs per rider are inevitable.
The one obvious linear corridor for rail service on the Eastside, Seattle-Bellevue-Redmond, is already mostly funded, and the line will obviously be completed to downtown Redmond in ST3. So what should be the next priority for East King?
If the goal is to build something for the cities that were left aside in ST2, that suggests Kirkland and Issaquah. So naturally, thoughts turn to a Kirkland-Issaquah rail line. But Kirkland and Issaquah are not a significant trip pair. Not even enough to warrant a Metro bus today. So it makes sense, if at all, only as a portion of a network connecting all the major Eastside cities and Seattle.
This is where the rail proposal begins to run aground. For Kirklanders, there are two dominant trip pairs, Kirkland-Bellevue and Kirkland-Seattle. Serving both well by rail means LRT on the Eastside Rail Corridor to Bellevue and also a LRT crossing of 520. Kirkland to Seattle via an East-Link connection is too roundabout to beat today’s Metro 255 service. So there has to be a 520 crossing to be competitive. But that is a LOT of rail; far more than is reasonable for a relatively small city with an underwhelming commitment to progressive land use policies.
I’ll pause here to explain why quality service in Kirkland necessarily means the ERC rather than I-405. The Corridor passes Totem Lake, Houghton, and the South Kirkland Park and ride. It also gets close to downtown. Of these centers, the 405 can only serve Totem Lake. So any solution on the 405 wouldn’t even connect Totem Lake to other Kirkland population centers. One could build feeder bus systems to freeway connection points near the 405, but this quickly turns simple trips by transit into roundabout multi-transfer affairs where speed and reliability won’t even match today’s Metro services. Crowded as the north-south arterials in Kirkland are, they at least point in the appropriate general direction. A 405-centric option requires that trips to the south and west will, for most riders, start by heading east.
405 service may make sense for cities further north and south. It’s likely the only viable connection from Bellevue to Renton, for instance, because the ERC south of Bellevue has engineering and property issues. It’s just a clearly second-rate option in the central part of the Eastside.
So the right way to serve the Kirkland-Seattle pair is by BRT on the Corridor. A dedicated busway on the corridor will pass the major population centers in Kirkland, and meet the HOT lanes on the 520 to connect with Link at UW or continue to Lake Union. Either way, it’s a big step forward for transit reliability and the estimated costs are just $180-240 million. The inferior 405 option is more expensive at $340-460 million, probably because it requires those expensive left-side ramps on the 405 of which there are none between Bellevue and Totem Lake. As for rail on the 520, the costs are 10-12 times higher for one minute saved and no additional ridership.
Once a commitment to UW-Kirkland BRT is made, the rail option for Bellevue-Kirkland is so much less promising. The corridor is just big enough to accommodate both, but it’s so obviously duplicative that it won’t pass the laugh test. With a UW-Kirkland BRT line passing the South Kirkland Park and Ride, a BRT line to Bellevue is already half-built. It could continue down the ERC until it runs out of corridor near the OMSF facility at NE 12th St. At that point, it probably needs to run on surface streets to reach the transit center on 108th Ave. But it’s a relatively short jog, and can be made better with signal priority and dedicated lanes, and include appropriate Link connections for trains to Redmond/Overlake.
So the entire Bellevue-Totem Lake corridor can be 90%+ dedicated ROW, probably the longest such corridor in the US.
If future demand warrants, the corridor could yet be converted to rail. Yes, even a bridge to Sandpoint. By then, there will have been decades for development to orient itself toward the corridor, and local politics may be more congenial.
Metro service to cities north and east of Totem Lake may be redirected their bus services onto the new BRT line, buying themselves better reliability and travel time, and further shrinking headways through Kirkland.
Any reason this wouldn’t work? One challenge is that the ERC, while closer to downtown Kirkland than the 405, isn’t quite close enough to be walkable. So transit needs to deviate somewhat from the ERC to get closer to the population center. But that’s a challenge for any mode or alignment in the city, and easier to resolve for buses on the ERC. The east end of downtown is where most future development is likely to go, and there is time for Kirkland to aggressively build out bus lanes in the area at fairly modest cost.
What about Issaquah? The rail/bus decision there is largely independent of what happens in Kirkland. But any ST service to Issaquah will mostly follow I-90 anyway, so the advantages of rail over bus in HOT lanes isn’t large. BRT would make an extension to Issaquah Highlands easy. Sound Transit estimates $30-40 million in additional expense vs $450-610 million for a LRT tunnel. Rail to the Highlands is pretty far down everybody’s priority list, so Issaquah needs to carefully consider whether it wants BRT to downtown and the Highlands, or rail to downtown alone.