February 16, 2021
David Zipper
With commuters grounded and passenger numbers likely to remain low in U.S. cities, public transportation leaders should focus on a different metric for usefulness: transit access.
Of all the information that U.S. public transit agencies track, none is more important to them than ridership — the number of people boarding its buses, trains and subway cars. Agency executives monitor their ridership data as closely as a CEO watching her company’s stock price. “We’ve always used ridership as our main metric,” says M.J. Maynard, CEO of RTC Southern Nevada in Las Vegas. “We’re constantly drawing comparisons with each other and bragging when our numbers are bigger.”
Dollars are at stake in addition to pride; ridership partly determines the amount of federal funding allocated to each system. The national transit industry scrutinizes passenger numbers too, celebrating a national uptickand bemoaning a downturn.
But the coronavirus pandemic has shown that ridership is an imperfect measure of transit’s importance. With offices shuttered and agencies themselves advising passengers to avoid all but essential trips, passenger counts collapsed by as much as 90% on rail service in Washington, D.C. and San Francisco. Ridership on buses has slumped as well. And these numbers are unlikely to snap back quickly to pre-Covid levels, as work-from-home habits forged during the pandemic stand to leave lasting marks on commuting patterns in major cities.
Few people would argue that these systems’ societal value has fallen as steeply as their ridership. On the contrary, the pandemic has reminded us that cities cease to function if public transportation is unavailable. You might be able to drive to a hospital or grocery store, but that won’t do you much good if transit-reliant workers can’t get there to staff it.
The pandemic is an extreme example of an external force that pushes transit ridership up or down for reasons no agency can control. Others include economic factors, socioeconomic change, land use patterns and the price of other transportation modes. For instance, an agency could add bus frequency but still see ridership fall because cheap gas nudged riders toward driving. Or an agency could do nothing differently at all, and then watch ridership grow during a prolonged period of unusually bad weather. In neither case do transit leaders deserve credit or blame for changes in passenger counts.
Given ridership’s limitations as a measure of success, it’s worth asking if an alternative metric could provide a clearer picture of transit’s value — and also help agencies make good service decisions. Happily, there is one — “access,” which quantifies a transit system’s ability to help people reach the places they want to go.
The basic method of calculating access is intuitive: Pick a particular neighborhood, and then determine the time it would take for a person living there to use transit to reach jobs dispersed throughout the region (people take many other kinds of trips, but commute data is most readily available). Transit planners can then aggregate the data to calculate an overall regional measure of access, or they can create one for a subset of the population (say, minorities or low-income residents). Agencies are then able to use these calculations when designing a systemwide service map or when making a narrower decision, like choosing whether to open a new route or add frequency to an existing one. An agency can continue to monitor the accessibility of its service, defined as the share of jobs reachable for a given population within a given trip time, such as 60 minutes door-to-door.
Access is a necessary-but-not-sufficient condition for strong ridership: It’s possible that a transit system offering improved access might still show a drop in ridership — say, because of a spate of equipment breakdowns — but a drop in access implies that ridership will eventually fall as well, because longer trips inevitably make alternative modes more attractive. “We’ve seen repeatedly that when a transit plan improves access it improves ridership,” says transportation consultant and author Jarrett Walker, who’s helped redesign bus systems in cities like Miami and Houston. As an example, he points to Santa Clara County, California, which pursued an access-focused revamp. Walker says ridership immediately rose 4% when the new network was implemented in 2019.
The idea of transit access isn’t new, but our ability to put a useful number on it is. David Levinson, a professor at the University of Sydney who has written numerous books about transportation access, says that quantitative breakthroughs now allow planners to make far more precise calculations than before. “We’ve got better data now through the General Transit Feed Specification and GPS, as well as from Census Bureau datasets. For each person, the data tells which block they live in and which block they work in. This didn’t exist at that detailed a level until the mid-2000s.”
Measuring access and putting this metric at the foreground of Covid-era planning could help transit agencies adjust their service to reflect shifting priorities. “The pandemic has forced us as an industry to remember why we’re here,” says Peter Rogoff, CEO of Sound Transit in the Seattle area and a former administrator of the Federal Transit Administration. “We have an absolute need to provide mobility for essential workers.” That’s a sentiment shared by many other agency leaders who have made preserving service for low-income riders a priority when weighing frequency reductions and route consolidations. Calculating proposals’ impact on access can better inform these decisions.
This concept of access can also help transit agency leaders plan how to ramp back up when the pandemic ends. “There is a chance to build back better,” says Rogoff, using one of President Joe Biden’s favorite catchphrases. “Transit riders in various communities will expect their service to return. Agencies will have less money while they face these expectations to resume service.”
Some agencies have already signaled a greater focus on access. To ensure that her agency’s service doesn’t simply default to what it was before, Maynard says her team in Las Vegas is developing an access metric to maximize the number of jobs available “within a reasonable period of time” for low-income and minority residents. San Francisco’s transit system has announced a similar plan, which it calls an Equity Toolkit.
Executives will need to keep watching ridership, but monitoring access as well can reduce distraction from the inevitable noise in passenger numbers. It will also reveal the massive influence that land use patterns have on transit service. Establishing new high-frequency “trunk lines” can improve bus access to downtown, but even an optimized transit plan can only reduce travel times so much between a residential community and a fast-growing employment center 40 miles away. “It’s easier and more cost-effective to provide transit in dense, urban areas,” says Carrie Butler, executive director of TARC in Louisville, Kentucky. “The problem is that’s not how most of our metropolitan areas are anymore.”
Transit agencies have a huge stake in whether post-Covid communities opt for density or sprawl.
Transit agencies may not have a direct say over land use decisions, but prioritizing the fundamentals of good service can trigger a virtuous cycle that helps create more transit-friendly places. Over the last decade, Seattle adopted a goal of maximizing the number of households within a 10-minute walk of 10-minute frequency transit service, and the city subsequently posted the fastest transit ridership growth in the nation. Passengers themselves have said they prefer frequent and reliable service to fare-free transit or tech enhancements like Wi-Fi.
There is another reason for agencies to elevate access as a success metric. With transit ridership likely to recover slowly after the pandemic recedes, critics of public transportation spending may cite lower passenger counts as a justification to reduce funding, which could push transit into a death spiral. By emphasizing the importance of access, agencies can untether policy debates from ridership numbers that might be wobbly for many months to come. With newly appointed U.S. Department of Transportation Secretary Pete Buttigieg already talking about how transit can unlock opportunity for those who are struggling, the language of access could provide the best framework for transit advocates to press their case.