New Riders in ST3

Link Morning Commuters at Westlake. Image by Oran.
Link Morning Commuters at Westlake. Image by Oran.

The completion of the Sound Transit 2 plan will more than double Sound Transit’s ridership from about 150 thousand today to 350 thousand, and ST3 will nearly double that again to between 561 and 695 thousand daily riders.

The ST3 plan would result in 657 to 797 thousand daily transit riders in the region in 2040. Bench-marked against a ‘no-build’ alternative, however, only 9% of those would be new to transit. Opponents of the measure repeat this factoid to argue ST3 will be ineffective in increasing transit mode share in the region, that it’s a poor value for money, and that it will not relieve congestion. Torture the data point enough, and it seems to yield a ludicrously high cost per added transit rider. But it’s a misleading number in several ways.

‘Cost per new rider’ is recognized as a terrible measure of value. The FTA discarded the measure in 2003 for a more comprehensive measure of system user benefits that includes travel time saved by all users. ‘Cost per new rider’ devalues the experience of existing riders and the time-saving and other benefits that accrue to them. Hundreds of thousands of riders will have a faster, more comfortable and more reliable journey.

Would anybody assess the value of a new highway only by counting new drivers? No. Any analysis of highway benefits would include time and money savings for all users, and so it is with transit. A focus on new riders also penalizes investments in core transit corridors (exactly where high-capacity transit needs to be). Providing alternatives to driving are important, but getting some people out of cars is not the only benefit of ST3.

Less obviously, the ‘no-build’ alternative is not the status quo. It is a highly optimistic 2040 scenario that incorporates all the long range plans of other transportation agencies and regional planners. The PSRC, WSDOT, Metro, and other transit provider plans are all completed whether currently funded or not. In this alternative world, bus service is far more ubiquitous and faster than today, and traffic is better managed to keep those buses moving reliably.

Why construct the ‘no-build’ this way? It maintains consistency between Sound Transit planning assumptions and the plans of all other agencies. But the assumptions underlying the ‘no-build’ scenario set a high benchmark that make rail benefits look smaller:

  • In the ‘no-build’ alternative, drivers face per-mile fees across the region to manage traffic levels. With better-managed traffic levels, buses move faster.
  • Travel times in HOV lanes are well-managed by raising HOV requirements as high as necessary for reliable transit speeds, or converting HOV lanes to bus only lanes. The political will to make these changes is uncertain, and not currently in evidence.
  • The ‘no-build’ alternative also assumes the complete build-out of WSDOT plans, many of which are currently unfunded.
  • Other transit agencies are assumed to complete their long range plans. Concurrent with the PSRC’s Transportation 2040 plan, the ‘no-build’ includes a doubling of local transit service. Those are only partly funded. The funding gap grows if ST3 is not completed and local agencies have to pick up the workload of the ST3 rail network.

In short, the no-build alternative isn’t free. It assumes large unfunded investments by other agencies, and those costs will grow if Sound Transit cannot build out the rail network after 2023.

Play out, if you will, an alternative where ST3 does not pass. Suppose other transit agencies are incompletely funded, or the political will for tolling and per-mile driver fees falters. In this very plausible scenario, failure to pass ST3 will reduce transit ridership by much more than 9%. In a world where buses are not faster or more reliable than today, the advantages of grade-separated rail are greater, and ridership gains are correspondingly larger.