Originally published on October 2, 2017
This is the third in a four-part series of blog posts recapping the 2017 Urbanization and Poverty Reduction Research Conference and the presentations of its speakers.
The main goal of transportation infrastructure is to get individuals to their destinations in an appropriate amount of time, making connections that allow a city’s markets to be accessible to other cities. Cities experiencing rapid urbanization, however, are limited in their connectability with other rural and urban areas due to congestion and infrastructure that has failed to keep pace with a growing population. Congestion, reducing the distance that workers can achieve in a daily commute, results largely from poorly maintained and inefficient roads. Some cities have thought creatively to address the issue, implementing policies such as road space rationing that use governance rather than infrastructure overhauls to restrict the number of vehicles on roads and decrease carbon emissions.
The second session of our Urbanization and Poverty Reduction Research Conference explored topics like congestion, public transportation, air pollution, and accessibility, beginning with a mini keynote from Somik Lall, the World Bank’s Global Lead on Territorial Development Solutions and Lead Economist for Urban Development in Africa.
Lall presented his findings on transportation within the urban setting, illustrating severe inequalities between employment accessibility in various cities. In London, one hour of travel opens the average worker to 3 million jobs, while workers in Nairobi are limited to under 40 percent of job availabilities if they use public transportation for the same amount of time. This issue with access and mobility is fundamentally tied to how cities are designed and oriented. Cities that are more fragmented with fewer dense areas and random urban formation struggle most with congestion.
According to Lall, transportation connections also give citizens more options and better prices. In the developing world, however, the main concern of policymakers is not how to make these connections, but how to make them with limited resources. In order to make connections available to all that allow people to make their livelihoods and cities to prosper, land use should be prioritized. Satellite imagery and remote sensing technology can give better insights in the urban planning process, leading to more efficient use of land.
While congestion is a significant problem in many of the world’s most rapidly urbanizing cities, it only tells one part of the accessibility story in urban areas. Uncongested mobility – speed in the absence of traffic – is drastically lower in cities with poor and underdeveloped road systems. While public policies tend to focus primarily on the issue of congestion, they might fail to recognize road conditions and proximity as major determinants of accessibility for workers. Gilles Duranton, Professor at the Wharton School of Business, discussed his research on accessibility and mobility, with specific attention paid to India’s urban layout.
Duranton found a tremendous amount of heterogeneity in mobility and accessibility across India, with an acute mobility problem in the nation’s urban areas. He also found that more roadways allow people to get to more places, yet an increase in roadways only has a small effect on mobility. By simulating 23 million real-time traffic trips on Google Maps, Duranton’s study found that Kolkata, Bangalore, and Hyderabad, three of India’s largest yet poorest cities, have the worst mobility and congestion. India’s relatively well-off, mid-sized cities recorded the fastest transportation times.
Congestion matters less than we think, according to the study – an important point for policymakers and urban developers to consider moving forward. In India, uncongested mobility, or a lack of mobility-friendly infrastructure even without traffic, explains 70 percent of the variance in mobility across India, while congestion only explains 15 percent. Proximity, additionally, accounts for 81 percent of accessibility.
Matthew Turner of Brown University had two specific research questions to answer: do subways reduce air pollution, and if so, by how much? In short, the answer his research found was ‘yes’. Subways typically reduce air particulates by 4 percent after a subway system opens, with the most benefits seen at the city center. Both Turner and Leah Brooks of the George Washington University asserted that subways reduce air pollution in the near-term and the benefits dwarf production costs. However, many policymakers and politicians are hesitant to implement large-scale transportation technology because subways are expensive and require a large amount of planning and subsidies.
Using examples primarily from Asia and Europe, Turner addressed some of the impacts subways have had across global cities. After the Taipei subway opened, air pollutants decreased by 5 percent after opening and by 15 percent after one year. In Los Angeles, a subway shutdown that spanned only 30 days caused a significant increase in traffic, and therefore a significant increase in dangerous air particulates.
As Somik Lall stated, cities are principally grappling with the challenge of making infrastructural and design improvements with few resources. Solutions like road expansion, redesign, and new subway construction are ideal, but political, physical, and financial barriers stand in the way of progress. Retrofitting new transportation infrastructure is extraordinarily expensive, but it is imperative that cities with poor mobility and accessibility find ways to make these changes and bring more opportunities to poorer citizens. The Urbanization and Poverty Reduction Research Conference thought deeply about policy and design solutions to these transportation issues and the full extent of the impact that they have on growing populations throughout the developing world.
