How Much to Invest in I-405 BRT
The revised ST3 plan adds a BRT stop and parking at NE 44th St in Renton
[Updated in paragraph three to clarify the description and cost of the added Renton station].
After Sound Transit released the draft system plan in March, some Eastside cities were unhappy it included a smaller investment in I-405 BRT than they had sought. Bellevue and Renton pushed for something closer to the "intensive capital" BRT with more parking and more stations using express toll lanes.
Some Eastside cities penned a joint letter, describing the proposal as comparable to ST Express service with improved headways, and demanding a much larger investment with more inline stops to create a BRT that is "the equivalent of light rail on rubber tires". The attempt to forge a coalition of the I-405 corridor cities fell flat. Several East and South King cities did not sign. Some who signed were small cities that do not border I-405. None of the Snohomish County cities participated.
The amended system plan made some concessions. Sound Transit had agreed in March to relocate Renton's downtown transit center to a more freeway-accessible location with 700 parking stalls. Renton pushed to expand the new South Renton transit center to accommodate 2,000 cars, and to add a second BRT stop at NE 44th St with parking for another 700. While the Board agreed only to 200 parking stalls in a surface lot at NE 44th St, the added center-line direct access facility adds $170 million to the cost of the BRT [updated]. An even more remote station with expanded parking at SE 112th in Newcastle was not included. Kirkland, taking a different approach, negotiated for more TOD in Kingsgate, reducing by 200 the planned parking expansion there.
I-405 BRT had lots of institutional momentum. The master plan for I-405, approved in 2002, envisions a BRT line with inline stations along I-405. To this end, Sound Transit has built transit centers and center ramps to the HOV lanes. WSDoT has created the express toll lanes north of Bellevue where buses could move reliably. With WSDoT now funded to extend the express lanes to the south, many observers expected a large investment in BRT on the corridor in ST3.
The plan ran up against uncomfortably low ridership numbers. Modelling suggests only 12,000 riders in 2040, and that the ridership isn't increased at higher investment levels. A pared-down BRT, much of which runs in general traffic lanes, attracts as many riders as the 'Cadillac' version.
Recognizing that the proposal for higher investment levels didn't stand up to close scrutiny, the Sound Transit Board in March advanced a draft system plan with just $735 million in capital investments, less than any of the options considered in the 2014 corridor studies. The low capital plan leveraged existing highway infrastructure with better and more frequent buses. Where center stations already exist, the BRT would run in the ETL lanes. Elsewhere, buses would run in general purpose lanes (or on the shoulder in a few locations north of Bothell).
The thwarting of institutional momentum left some cities feeling that a promise was broken. In many cities along the I-405 corridor, the political imperative of a tangible local investment can only be met via BRT. Yet few votes are contingent on the difference between higher and lower grade BRT.
The ridership estimates highlight the limitations of suburban transit oriented around highway buses and park-and-rides. On a highway serving 800,000 trips per day, 12,000 bus riders will scarcely make a dent in traffic congestion. Yet more investments wouldn't help. A larger investment would divert resources from the more urban places on the Eastside to the impossible task of 'solving traffic'.
Auto congestion has created political momentum for WSDoT to build a second HOT lane on the northern part of I-405 or expand capacity around SR 522. Though the added lane is currently unfunded, it has raised the prospect of complementary Sound Transit investments. However, there is no evidence highway expansion would make transit more productive. A second HOT lane would tend to reduce toll rates for express lane users, which may diminish ridership. In any case, the highway north of Bothell is mostly in Snohomish County, where I-405 BRT is a lower priority.
Transit advocates are often skeptical of corner-cutting in BRT projects. But this is a project where some prudent whittling seems exactly the right course. Sound Transit can gain the maximum ridership with a moderately sized upgrade to I-405 express buses, fulfilling the 'promises' of the Master Plan and conserving resources for other worthwhile projects.