The Future of Public Transportation and Research Needs

For well over 15 years, the ASCE Journal of Transportation Engineering, Part A: Systems and its predecessor journals have been publishing articles on public and urban transportation (Sinha 2021). Public transportation papers have addressed planning, design, construction, and operation for multiple transit modes, including buses, light rail, and heavy rail. The focus of this work has largely been on urban public transportation in Canada and the United States, and we will continue that focus in this editorial. We will also use the terms public transportation and transit interchangeably.

In North America, the first national crisis for public transportation occurred post–World War II, when the vast majority of privately run North American public transportation systems essentially went bankrupt and were taken over by publicly operated and local transportation authorities. These systems were generally designed for commuter travel from the external suburbs to the central business district (CBD). Such legacy commuter routes were often light or heavy rail. They still exist and still serve these commuter movements. For the past 60 years, public transportation systems have been operated as a social service. With few exceptions, public agencies did not have the funds to develop new subway lines and instead relied on extending bus routes to address new passenger movements (e.g., suburb to suburb). In this way, public transportation in North America is now designed and operated to provide mobility for citizens who, for a variety of reasons, do not have access to automobiles. However, because of cost considerations, the service times of the new services have been relatively high. The result is that, while it is relatively easy to travel from a suburb to downtown, traveling from suburb to suburb, or even within a given area, often takes a substantial amount of time, particularly when compared with private vehicles.

While continuing to provide a variety of social benefits, public transportation systems face many challenges. The general decline in ridership over the past 50 years was accentuated by the effects of the COVID-19 pandemic. Public transportation systems in North America are facing a crisis every bit as severe as that which occurred 60 years ago. Fortunately, opportunities for improvements exist, with the additional pandemic funding provided to public transportation properties in the past few years. In this short editorial, we describe these benefits, challenges, and alternatives as a framework for suggesting research needs.

Public transportation provides numerous economic and social benefits. Many public transportation riders, including children, the elderly, people with disabilities, and low-income individuals have severely limited access to private transportation or none at all. Current public transportation systems have been designed to meet the needs of this population. In general, urban geographic coverage is excellent in that travelers can travel from any point to any other point in urban areas. The trade-off is that service times are relatively limited so that public transportation riders often face relatively long travel times. This is particularly true for routes that the system was not designed for, such as suburb-to-suburb trips. A well-designed public transportation service over a comprehensive network can aid social equity as a result.

Unfortunately, public transportation services were often designed decades ago and are not very robust at connecting lower-income citizens, often located near city centers, with job opportunities or social services in outlying suburbs. In the aggregate, public transportation with high vehicle occupancy is often less expensive to operate than private vehicles, such as serving trips for commuting to a CBD. By diverting private vehicle trips, high-occupancy public transportation can reduce roadway congestion and prevent additional emissions from single-occupancy vehicles. Public transportation can also aid transport resiliency by providing emergency services for transportation or shelter.

Public transportation faces numerous challenges. In the United States, transit ridership per person and as a proportion of all trips has been declining over time, reducing transit benefits. The COVID-19 pandemic saw a precipitous decline in ridership, which has yet to return to prepandemic levels.

Since the COVID-19 pandemic, shared ride services have faced continuing concern from riders about local infection and are often cost-prohibitive for daily trips. A major transit market, commuting to CBD jobs, has declined due to telecommuting. As noted above, many of the benefits of public transport depend on high-occupancy services. Funding for transit continues to be a problem in many areas as fare box revenue does not cover costs and because pension payments for retired workers have increased. Improvement in communications can reduce the base level demand for travel (Caldwell et al. 2021). Finally, electrification of transit buses (in conjunction with renewable power) is needed to mitigate local air pollution emissions from diesel engines and to reduce emissions of greenhouse gases (Hendrickson and Rilett 2022).

Public transportation has significant opportunities to implement new and more cost-effective services. Mobility as a service (MAAS) can complement traditional bus and rail services by allowing users to identify the best options for a given trip from a variety of public and private transportation services. Transit can take on the role of community “mobility manager,” promoting more modes of transportation (including carpooling and vanpooling). Transit can also work to promote active transport, as with provisions for carrying bicycles on transit vehicles. Automation may provide an opportunity to reduce costs, especially for first-mile, last-mile, and off-peak services. Demand-responsive services can be effective in many cases.

Since the 1960s, many areas of the world have pursued transit-oriented development to reduce urban sprawl and insure adequate density for effective transit. This strategy is becoming more common across the US. While changes in urban form happen only slowly, there is evidence that mixed development is already occurring in many urban areas.

Policy innovations are needed to make transit viable in this environment of many challenges but also opportunities. More flexibility in the use of available public funding would be advantageous. Allowing traditional transit funds to be used on pilot programs, new technologies, or additional modes of travel might allow transportation systems to better meet the needs of their communities. Better integration with bicycling or other new modes might be helpful. Targeting services to improve equity can be pursued, especially for people unable to or preferring not to drive a single-occupancy vehicle. Ensuring equitable access to employment, education, food, and medical services might also be priorities. Free transit in selected areas is a topic of current interest.

Research opportunities for public transportation abound. Real-time optimization of operations and service alternatives are already topics of widespread interest. However, there are a variety of potential infrastructure investments and policy innovations that deserve attention. International comparisons and case studies of successful innovation implementations would be particularly useful. Readers of the Journal of Transportation Engineering are encouraged to work with local transit and MAAS providers to develop, deploy, and test such innovations. The journal is eager to publish such work (Hendrickson and Rilett 2019).