Some time ago, professor Christo Venter of the University of Pretoria sent me an intriguing message: Did I have data on how bus rapid transit systems, or BRTs, affect equity in cities? Impact evaluations for changes in travel time, cost, traffic fatalities and air pollution, not only in total but disaggregated by socio-economic group, geography or other factors? I pulled together everything I could find, including many articles published in the gray literature, but there wasn’t much.

Six years later, with great patience and the help of Gail Jennings (now at WWF) and support from Andrés Felipe Valderrama Pineda of Aalborg University, Venter has completed an extensive review of 68 publications that touch on equity and BRT, directly and indirectly, and published the results in the International Journal of Sustainable Transportation (he was also gracious enough to include me as a co-author).

Why Equity and Why BRT

If the three legs of sustainable development are social, economic and environmental, equity is sometimes defined as the overlap between social and economic. As a result, it’s not always given the consideration it deserves, as the economic and environmental components of sustainability get the most attention. WRI is working in its own way to help change this with the latest edition of our World Resources Report, “Towards a More Equal City.”

In the WRR – which spans several working papers, the latest of which tackles housing – we take equity as our entry point and ask how it affects economic and environmental outcomes in cities. This paper by Venter et al. comes at a timely moment in the development of the transport working paper, which will build on the work of Karen Lucas, Eduardo Vasconcelos, Karel Martens and Aaron Golub, among others, on social justice.

Bus rapid transit is a relatively recent mass transit “technology” capable of improving urban mobility through a package of interventions, including busway improvements, reducing travel times and costs, upgrading urban corridors, and mitigating carbon emissions and road safety risks. According to BRTData, there are currently 452 BRT corridors around the world, covering 5,655 kilometers, 205 cities and serving more than 34.3 million passengers a day.

We found in our review that many BRT projects are rhetorically positioned as pro-poor in developing countries and their political acceptability is often linked to a larger policy agenda aimed at alleviating poverty by improving access to transport and reducing costs. But we also found that, despite the mandate by international development institutions to help eliminate extreme poverty and the fact that many BRT projects have financial assistance from major development banks, methods to measure the impact on the urban underserved are not widespread.

Impacts on the Underserved

BRT implementation usually reduces travel time, travel cost, traffic fatalities and air pollutant emissions. But impacts on particular groups of society are reported in very few cases. Most of the few examples are positive but not all:

• A study of Bogotá’s TransMilenio Phase 1 by Tito Yepes and myself found higher travel time savings for poor people (18 minutes per trip) than for middle income passengers (10 minutes). Low-income passengers, who would have paid two fares on the traditional system, saved 8 to 12 percent of their daily income.
• Tiwari and Jain (2012) showed that both cyclists and bus users saw reduced travel times (on the order of a 33 percent reduction) when using the Delhi BRT corridor. As most non-motorized transport users are from low-income households, the benefit is likely to be progressive.
• Scholl et al. (2016) found Lima’s integrated and flat fare pricing structure promotes BRT usage among the poor by reducing the cost of longer trips below those of traditional modes of transport.
• An evaluation of Lagos’ BRT found the standardization of fares that used to vary by the hour brought cost savings to many passengers.
• In a distributional analysis of costs and benefits for BRTs in Bogotá, Mexico City, Istanbul and Johannesburg by WRI, investment was found to be progressive. Benefits exceeded costs by a larger proportion for lower income groups than for higher income groups. In all cases except Istanbul, the highest income group experienced a net loss (costs exceeded benefits), indicating that BRT serves an income distributive function. However, very low income users are usually underrepresented as BRT riders because they are priced out by fares.
• There is also evidence that it is possible for BRTs to exacerbate inequality. BRT has been used as a tactic to transform existing informal or semi-regulated public transport operations, like minibus networks. Some new systems in Latin America and South Africa have attempted to incorporate existing drivers and minibus owners into the BRT, but have met with limited success due to lack of driver qualifications. As a result, there can be negative spillover effects on both drivers and owners, which fall disproportionately on lower-income groups.

“An Evolving Project”

While this evidence gives an indication of progressive impacts, there are several caveats. The identification and measurement of equity impacts is hampered by the lack of a clear and consistent framework for analyzing equity that can be applied and compared across different locales. Better data are clearly needed to support more rigorous assessment of equity impacts in transport implementation.

Ultimately, as Christo Venter indicates:

Paratransit reform is an evolving project; no consensus has been reached about the most appropriate paths to be followed. But regardless of the path, it is important that authorities carefully consider equity impacts and mitigation of negative spillover effects via effective regulation and transitional strategies.

Bus rapid transit systems possesses characteristics that enable them to provide service to traditionally under-served populations better than other mass transit alternatives. Their relative low cost and rapid implementation can improve travel time and travel costs for low-income populations faster and more effectively than rail options. And if “complete streets” concepts are used, they can benefit pedestrians and bicycle users too.

Nevertheless, the impact of BRTs on equity is not automatic. They need planning and careful design and implementation. There is the potential for affordability and accessibility problems, displacement of low income dwellers as land prices increase due to better access (i.e., gentrification), as well as spillover effects on incumbent transport operators.

Darío Hidalgo guides the WRI Ross Center for Sustainable Cities’ international team of transport engineers and planners.