For the first time in human history, more than one-half of the world's population lives in cities. The global urban population growth rate averages 2 percent annually (compared to an annual rural growth rate of 0.3 percent), and the number of megacities - those with populations in excess of 10 million people - has quadrupled in the past two decades. These trends are expected to continue, dominated by demographic shifts in the developing world. The United Nations predicts that more than 80 percent of population growth in the next ten years will occur in the urban areas of developing countries.
A major prerequisite for both economic growth and human welfare in all urban areas is sustainable transport: the development of clean, safe, reliable, and affordable systems for delivering goods and moving people. However, in many developing countries, pollution, congestion, and questionable safety are resulting in serious environmental, economic, and social consequences for the fastest-growing regions of the world. Some of these consequences are discussed below.
Figure 1: Transport Growth in Selected Developing Countries
Source: EarthTrends, 2006 from the International Road Federation, 2003.
Traffic Congestion
Vehicle ownership is rising 15 to 20 percent annually in much of the developing world due to increasing urban wealth (World Bank, 2002). Yet most countries have not matched this growth with parallel expansion of transportation infrastructure, including roads, public transport, and traffic management systems. As a result, traffic congestion is severe and overall mobility is declining in most cities. Figure 1 shows growth in vehicle ownership and road networks in six of the world's largest developing countries. In each country, vehicles are added to roads more quickly than new roads are built. However, vehicle ownership rates are still relatively low in developing countries, ranging from 15 percent in more affluent countries such as Mexico and Brazil to less than one percent in India and Nigeria.
The negative consequences of increased traffic tend to disproportionately impact the urban poor. Growth in private vehicles has reduced demand for and eroded the quality of public transport in developing countries, which is typically characterized by long wait times, overcrowding, and irregular stops. The urban poor also rely heavily on nonmotorized transportation, such as biking or walking, which has become dangerous with the presence of motor vehicles. Urban road accidents cause over one million deaths and 15 million injuries each year in developing countries, over half of which involve pedestrians or bicyclists (World Business Council for Sustainable Development, 2004).
Figure 2: Share of Total Road Related Deaths by Category of Road User in 2000
LDV = Light Duty Vehicle
OECD = Organisation for Economic Co-operation and Development
Source: World Business Council for Sustainable Development (WBCSD), 2004.
Mobility 2030: Meeting the Challenges to Sustainability
Pollution and Human Health
The World Health Organization estimates that urban air pollution causes 800,000 premature deaths each year. Fossil fuels burned by motor vehicles contribute 90 percent of urban air pollution, including lead, carbon monoxide, ozone and suspended particulate matter. Although urban air pollution is a problem worldwide, vehicle emissions are particularly high in developing countries due to the prevalence of fuel-inefficient technologies and practices such as two stroke engines, high average vehicle age, poor vehicle maintenance, low-quality fuels, and severe traffic congestion.
Figure 3: Deaths from Urban Air Pollution (UAP) in 2000
Source: World Health Organization, 2005.
The transportation sector also accounts for over 18 percent of global carbon dioxide emissions and is a significant contributor to global warming (EarthTrends, 2005). Currently, industrialized countries contribute roughly three times more transport-related greenhouse gas emissions than do developing countries. However, rapid motorization and population growth in the developing world are closing this gap. If China and India were to achieve per capita vehicle ownership levels comparable to those in the United States - roughly three cars per four people - the number of vehicles in the world would nearly triple.
Economic Consequences
In many cities including Bangkok, Manila, São Paulo, and Shanghai, downtown weekday traffic speeds average 15 kilometers per hour (9 miles per hour) or less (World Bank, 2002). The economic cost of congestion has reached over three percent of Gross Domestic Product (GDP) in many cities. Furthermore, urban road accidents cost developing countries US$65 billion each year, and in the most heavily polluted cities, economic losses from air pollution reach 10 percent of GDP. Developing countries also stand to suffer most from the consequences of climate change, with the poorest countries losing an estimated five to nine percent of their total GDP.
Options for Sustainability
Creating sustainable transportation solutions in developing countries will require reducing local and global air pollutants, mitigating traffic congestion, improving road safety, and removing mobility barriers for the urban poor. These goals may be achieved through a combination of policies that introduce new technologies, enforceable standards and strategic improvements to transportation infrastructure.
Fuel policies can influence both the quality of existing fuels as well as the selection among available fuels. Potential strategies include:
- phasing out leaded and high sulfur fuels;
- introducing fuel alternatives such as compressed natural gas and biofuels; and
- implementing fuel-quality monitoring to reduce local corruption with additives such as kerosene.
Vehicle policies can increase fuel-efficiency and reduce total emissions. Potential strategies include:
- promoting fuel-efficient vehicle technologies;
- introducing fuel consumption and emissions standards; and
- implementing vehicle inspection and maintenance programs.
Transportation infrastructure policies can relieve congestion by reducing demand and increasing capacity while specifically addressing social issues such as safety and equity. Potential strategies include:
- prioritizing public transport (see Box 1: Bus Rapid Transit in Mexico City);
- improving traffic management systems; and
- segregating nonmotorized forms of transportation from motorized traffic.
Box 1: Bus Rapid Transit in Mexico City
In 2002, EMBARQ, The World Resources Institute's Center for Sustainable Transport, initiated a partnership with the Government of Mexico City and the Centro de Transporte Sustentable de Mexico (CTS-Mexico) to develop a 20-kilometer bus rapid transit (BRT) system. The new Metrobus began operating in June 2005 and carries 263,000 people daily. It has cut both average travel times and passenger exposure to air pollutants in half and reduced CO2 emissions by 47,000 tons annually. Increased productivity due to time saved is estimated to approach $15 million per year. Major cities in other countries including India, Vietnam, and Turkey are working with EMBARQ to emulate this model.
There are no quick fixes for urban transportation problems and numerous obstacles remain. Improving transportation in developing countries will require several decades and concerted cooperation between businesses, governments, and the public sector. The cost and convenience of existing technologies must also improve before they become socially and economically viable for low income countries. However, several promising models of sustainability, including Mexico City's BRT system, already exist and are being replicated in developing countries.
RELATED LINKS:
The World Bank: Urban Transport Information
EarthTrends
Feature: Sustainable Cities, Sustainable Transportation
Transportation Data Table: Selected City-Level Indicators
Other Publications
Cities on the Move:
A World Bank Urban Transport Strategy Review (pdf)
Mobility 2030: Meeting Challenges to Sustainability
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