What causes low urban travel speeds?

In cities across low- and middle-income countries, traffic crawls 24 hours a day. In Dhaka during rush hour, speeds average around 15km/h. At three in the morning, when the roads are empty, they average about 20km/h. Urban transport in the developing world is not only slow because of congestion. And so congestion policy, Adam Storeygard of Tufts University argues, gets you a small fraction of the way to solving the problems of urban transport in LMICs.

That counterintuitive finding is one many themes in Storeygard's wide-ranging review of what research actually tells us about how people in LMICs get from A to B. From informal minibuses to bus rapid transit, from a field experiment in Bangalore that tested congestion pricing to the long shadow of colonial railroads still shaping African trade today, the picture that emerges is more nuanced and more interesting than many policy blueprints suggest. He tells Tim Phillips what the evidence supports, where it runs out, and why fixing the roads won’t fix everything.

The research behind this episode:

Storeygard, Adam. 2025. "Transport in Low- and Middle-Income Countries." NBER Working Paper 34354. Forthcoming in a special issue of Regional Science and Urban Economics.

To cite this episode:

Phillips, Tim. 2026. "Transport in Low- and Middle-Income Countries." VoxDev Talk (podcast). 

Assign this as extra listening: the citation above is formatted and ready for a reading list or VLE.

About Adam Storeygard

Adam Storeygard is Professor of Economics at Tufts University, where his research focuses on urbanisation, transportation, and the economic geography of the developing world, in particular sub-Saharan Africa. Much of his work uses geographic and satellite data to study how infrastructure shapes where people live, how they move, and how economies develop.

Research cited in this episode

Akbar, Prottoy Aman, Victor Couture, Gilles Duranton, and Adam Storeygard. 2023. "The Fast, the Slow, and the Congested: Urban Transportation in Rich and Poor Countries." NBER Working Paper 31642. The paper behind the Dhaka finding: assembling travel speed data across 1,200 cities in 152 countries, the authors show that cities in poor countries are roughly half as fast as those in rich countries, and that most of the gap is not congestion but structural low speeds in the absence of traffic.

Björkegren, Daniel, Alice Duhaut, Geetika Nagpal, and Nick Tsivanidis. 2025. "Public and Private Transit: Evidence from Lagos." Working paper. When Lagos introduced a major new public bus system, informal drivers on affected routes left,  so bus frequency on those routes fell on net. The big benefit accrued to other routes that informal drivers switched to, where prices and waiting times fell. Winners and losers, not a clean gain.

Franklin, Simon. 2018. "Location, Search Costs and Youth Unemployment: Experimental Evidence from Transport Subsidies." Economic Journal 128 (614). A randomised trial in Addis Ababa: providing transport subsidies to unemployed young people helped them search for and find formal jobs. Effects did not persist once subsidies ended, raising questions about how much the transport constraint itself was the binding one.

Borker, Girija. 2021. "Safety First: Perceived Risk of Street Harassment and Educational Choices of Women." World Bank Policy Research Working Paper 9731. Women in Delhi attend less selective colleges than male peers with identical academic credentials, not because they are not admitted, but because of perceived harassment risk during the commute. Delhi university students overwhelmingly live with their parents, and the daily journey matters as much as the institution.

Kreindler, Gabriel. 2024. "Peak-Hour Road Congestion Pricing: Experimental Evidence and Equilibrium Implications." Econometrica 92 (4). A field experiment in Bangalore, paying drivers to avoid congested areas and times. The finding: congestion pricing would produce only modest benefits in Bangalore because traffic density has a relatively moderate impact on speed there, meaning you would have to charge astronomically high prices to shift behaviour significantly.

Jedwab, Remi, and Adam Storeygard. 2022. "The Average and Heterogeneous Effects of Transportation Investments: Evidence from Sub-Saharan Africa 1960–2010." Journal of the European Economic Association 20 (1). Shows how transportation infrastructure investments, including the legacy of colonial railroads built primarily to connect mines to ports, continue to shape where Africans live and how countries trade, with consequences that push African economies toward overseas rather than intra-regional commerce.

More VoxDev Talks on this topic

Michelson, Hope, 2026, “African agriculture's underappreciated supply side.” VoxDev Talk. How transport links are one of the many impediments that stop rural farmers from making the most of the opportunities of better agricultural inputs.

Related reading on VoxDev

"Urban transport infrastructure in developing countries”, the VoxDevLit review of research on urban transport in LMICs, covering buses, BRT, subways, and informal transit networks.

"Who wins when public transit challenges private transit?”, the Lagos bus reform discussed in this episode, with further detail on how informal drivers responded to new public routes.

"Perceived risk of street harassment and college choice of women in Delhi”, Girija Borker's research on how commute safety shapes women's educational choices, as discussed by Storeygard in this episode.

"The equitable benefits of Colombia's bus rapid transit system”, complements the discussion of BRT in Bogota, one of Storeygard's three best-evidenced cases for BRT benefits.