Think Again

10 Million Sardines in a Sea of Skyscrapers

How sprawling megacities -- from Lagos to Mumbai -- might just save the world.


“Megacities Pose the Most Dire Development Crisis of the 21st Century.”


“Megacities Pose the Most Dire Development Crisis of the 21st Century.”


Two hundred years ago, just 3 percent of the world’s population lived in cities. Today, cities hold more than half of all people on Earth. The number of urban residents is growing by nearly 60 million every year, a trend driven by rapid industrialization, rural-urban migration, and globalization. If this pace continues, by 2050 over 70 percent of people will call cities home.

The largest of today’s urban centers are known as “megacities.” Behemoths of tightly packed humanity, each megacity holds more than 10 million people. Back in 1950, only New York City held that distinction. Today 24 cities do, and at least a dozen more are expected to join the club by 2025. Most megacities are and will continue to be in the developing world — Delhi, Jakarta, Shanghai, and Lagos, to name a few.

It’s easy to look at statistics and view megacities as the looming development crisis of this century. The United Nations estimated in 2006 that there was just one toilet for every 1,440 people in Mumbai’s Dharavi slum. In Cairo, meanwhile, traffic has gotten so bad that a recent World Bank report estimated that congestion costs the economy upwards of $8 billion each year in lost productivity.

Seizing on these gritty details, many journalists, environmentalists, and leaders of NGOs and development organizations portray megacities as calamities — vast, open sewers that fuel a vicious cycle of poverty, increase income and health disparities, and degrade the environment. NGOs routinely highlight the worst of megacities (and garner support for their work) by telling stories of human desperation. Larger institutions like the World Health Organization emphasize figures, such as the fact that Cairo residents inhale the equivalent of a pack of cigarettes in air pollution each day, on which the international media feed. Others are more direct in their criticisms: Joel Kotkin, a professor of urban development, argued in a 2011 Forbes article that “megacities in developing countries should be seen for what they are: a tragic replaying of the worst aspects of the mass urbanization that occurred previously in the West.”

To be sure, tens of millions of people in megacities do live in poverty and pollution. But emphasizing megacities’ economic, social, and environmental problems discounts the fundamental opportunities they provide and the enormous capacity their residents possess. The popular perception is, in a word, incomplete.

In fact, the vast size and dense concentration of people and resources in megacities, which currently produce some 14 percent of the world’s economic output, are their greatest assets. They are tools that can actually be used to drive economies, diminish poverty, and empower residents.

Making proper use of these tools is critical because mass urbanization is inevitable. From Europe to North America to Asia, no country has ever developed without it. Moreover, the world has already seen how megacities can emerge and grow in a sustainable way. In Seoul, for example, infrastructure projects and economic reforms from the 1960s onward helped transform South Korea from one of the world’s poorest economies (equivalent to modern-day Benin) into the 15th largest, becoming a global commercial hub.

Transforming developing megacities — and soon-to-be megacities — will certainly take time, and no two cities will transform in the same way. Seoul had highly centralized governmental structures that not all cities do, especially those in poorer countries. But there are other ways to leverage the power of density, technology, and economies of scale. Megacities hold enormous value for the developing world, and ensuring that they deliver this value starts, fundamentally, with no longer seeing them as utter catastrophes.

“Megacities Are Too Crowded.”


Decades ago, Paul Ehrlich’s famous book, The Population Bomb, offered an apocalyptic vision of an overpopulated planet subsumed by social upheaval, starvation, and mass death. Today, most experts agree that Ehrlich’s concerns were overblown. Yet a similar argument is now being directed at megacities. In 2012, Wendell Cox, an urban policy expert, wrote an article titled “Pakistan: Where the Population Bomb Is Exploding” that highlighted Karachi’s massive growth. In 2011, Paul James, then director of the Global Cities Research Institute, told the Economist that “restricting the growth of cities — in the sense of limiting their sprawling and bloating — will, overall, improve the quality of life for humans on this planet.”

Existing and emerging megacities are big, of course, and growing fast, which can make them seem chaotic and crushing to the Western eye. But big is not always bad.

To say megacities are too crowded “doesn’t make sense from an economic point of view,” Indermit Gill of the World Bank’s development economics unit said in an interview. He explained that as countries develop, people and economic activity always become more concentrated in urban areas. This process of “agglomeration economics” is a good thing because it reduces production costs, allows businesses to share infrastructure, and provides large labor markets. In megacities, the scale of the phenomenon is even greater than it is in other cities.

Already, concentrations of cheap labor, industry, and markets in megacities and other urban centers heading toward “mega” status are vital to their countries. According to researcher David Satterthwaite, Mumbai contributes some 6 percent of India’s GDP, despite having less than 1.5 percent of its population. In addition, megacities have per capita GDPs that are significantly higher than national averages. The difference is even more extreme in developing megacities. For example, Bangladesh’s per capita GDP is $1,044, according to the country’s Bureau of Statistics, but Dhaka’s is more than $3,000. And these trends seem likely to continue. “Emerging market mega- and middleweight cities together … are expected to contribute more than 45 percent of global growth from 2007 to 2025,” consulting firm McKinsey found in a 2011 report.

Bigger cities also better enable governments to deliver public services. McKinsey has estimated that it is 30 to 50 percent cheaper to provide fundamentals like housing, water, and education in populated urban areas than it is in rural ones. This helps explain why 90 percent of urban households in the developing world have access to electricity, compared with just 63 percent of rural households. Governments should provide such essentials to all their citizens no matter where they live, but in megacities they can often do so more quickly and efficiently.

As their populations grow, megacities’ human density will eventually decline — a natural progression in which residents get richer and new areas are built to accommodate them. (Con
sider glitzy satellite cities and suburbs of New Delhi like Gurgaon and Noida.) As that happens, however, the importance of agglomeration manifests in a new way: Governments work to enhance physical mobility in order to keep people and resources closely connected. Governments in Asia have been doing this for years, developing high-speed rail and other transportation options. Governments in other parts of the world are catching on: Dar es Salaam, Tanzania, is installing a rapid-transit bus system, and Nigeria is building a high-speed rail network to connect Lagos with other cities.

Governments, in other words, increasingly recognize that density pays, and they are working to keep people in a tight urban embrace.

“But Megacities Aren’t Benefiting People in Slums.”


It’s certainly not news to say that, within megacities, the poor often live in slums: eyesores of crowded shanties and trash. In Pakistan, slum growth has accounted for nearly all recent urbanization. In Lagos, slums hold more than 70 percent of the city’s population. U.N.-Habitat has called slums “the most intolerable of urban housing conditions,” while books like Mike Davis’s Planet of Slums portray the areas as post-industrial wastelands. Some development experts have even called for them to be bulldozed and their residents relocated.

But though slums may not be desirable places to live, a billion people call them home for good reason. Rural poverty rates are much higher than urban ones, and people thus go to megacities seeking better lives. Slums are their gateways, quickly absorbing migrants by offering cheap housing and informal work in close proximity; this is especially true in Africa, South Asia, and Latin America. As Edward Glaeser, author of Triumph of the City, puts it, “Cities aren’t full of poor people because cities make people poor, but because cities attract poor people.”

Slums provide the first rung on the ladder of urban opportunity. Consider Rio de Janeiro, where Janice Perlman, founder of the Mega-Cities Project, which researches urban management around the world, began tracing the mobility of residents in the city’s favelas in 1969. She found in 1999 that of the 36 percent of her original random sample group that she was able to locate, 67 percent, as well as 65 percent of their children, had moved out of the slums; 40 percent had become renters or owners of houses or apartments in other neighborhoods, and 27 percent were in improved public housing. Those who remained in the favelas cited better access to public services and better household amenities over the survey period.

Much of the economic opportunity that slums offer is through vibrant, informal marketplaces. Typically, every alleyway is a thicket of businesses and services: barbershops, food stalls, clothing shops, and more. In Mumbai’s Dharavi, some 17 percent of structures are not actually homes but factories, shops, and offices, many of which are thriving. Small-scale leather, textile, and pottery factories in Dharavi have an estimated annual output of over $500 million.

Grassroots, demand-driven solutions to everyday problems also create opportunity. In East African slums, particularly those in Kenya, women without enough assets to obtain formal bank loans participate in “merry-go-round” systems in which they pool money together — less than a dollar a week per person, typically — from which members can take loans.

These informal markets and networks often make living in slums more of a conscious choice than critics of megacities assume. For this reason, “slum upgrading” projects, meant to improve people’s lives by moving them elsewhere, have routinely faced local opposition, according to Robert Neuwirth, author of Shadow Cities: A Billion Squatters, a New Urban World. In Nairobi, for example, the government attempted to relocate several hundred residents and businesses of Kibera, the city’s largest slum, to new apartment blocks starting in 2003. But many people rented the apartments out, took the cash, and moved back to the slum, where they had jobs, businesses, and social bonds that could not easily be replicated elsewhere.

This is not to romanticize poverty. The creativity and entrepreneurship on display in slums should not preclude governments from taking a stronger interest — and making larger investments — in residents’ health and well-being, which are in dire need of improvement. In Nairobi’s slums, for instance, child mortality is 2.5 times greater than in other parts of the city due to factors such as poor sanitation and minimal health care.

That said, it is also wrong to write off slums as cesspools or to say that they just need to be cleaned up or torn down. As Glaeser argues, slums are not a curse; they are signs of a healthy city.

“Megacities Can’t Be ‘Healthy,’ Because They’re Killing the Planet.”


Megacities are among many environmentalists’ favorite targets — a modern “tragedy of the commons.” Critics point out that cities are responsible for 70 percent of carbon dioxide emissions and that while Western megacities generally have efficient waste management, emissions regulations, and clean mass transit, most in the developing world do not. In Beijing, for instance, air quality has become so bad that media outlets have started referring to the phenomenon as the “airpocalypse.” Scientist Charles Kolb, who has studied megacity emissions, said at the 2009 national meeting of the American Chemical Society that pollution from these urban centers “make them immense drivers of climate change.” Based on his presentation, the society reported, “Controlling urban growth in the developing world is key to improving the world’s air quality.”

Yet megacities are greener than many people think — and they can become even more so.

For starters, large cities offer environmental benefits that rural areas do not. Across all developing countries, 70 percent of urban households have access to modern cooking fuels (electricity, gas, kerosene), compared with just 19 percent of households in rural areas, where heavy burning of coal, wood, and other biomass contributes to deforestation and air pollution. As Stewart Brand, an environmentalist and the founder of the Whole Earth Catalog, a
guide to sustainable living, has written, “[I]n the developing world, their [cities’] greenness lies in how they take the pressure off rural waste.”

Recent data also show that as urban areas enlarge, the growth rate of their emissions actually decreases. “[J]ust like biological organisms, the energy metabolism of metropolitan areas slows down as they increase in size: larger regions burn less energy per capita than smaller regions,” the Martin Prosperity Institute, which studies urban issues, reported in 2009. When people are closer together, infrastructure and resource usage becomes more efficient. Larger cities have less road area per person, more intense use of public transportation, and shorter electrical transmission cables (which means “less loss of electricity and in turn lower CO2 emissions,” according to the institute).

Density also allows megacities to scale up green projects in a big way. In the past decade, several megacities have made buses, taxis, and auto-rickshaws convert from burning petrol to using more environmentally friendly natural gas. A policy implemented in Dhaka, Bangladesh, in 2010 has converted over 40 percent of the city’s vehicles to natural gas, reportedly averting 2,045 premature deaths from air pollution and saving an estimated $409 million (around 0.4 percent of Bangladesh’s annual GDP). Sanergy, a company in Nairobi, is installing thousands of pay-per-use toilets that will convert the city’s human waste into productive assets: cheap fertilizer for farmers and renewable energy from biogas that can help fuel the city’s electrical grid. And other scalable ideas abound: According to a 2008 study from Lawrence Berkeley National Laboratory, if the world’s 100 largest cities painted all their structures’ roofs white and used more reflective paving material, it would offset nearly 44 metric gigatons of greenhouse gases. This is because more reflective surfaces absorb less heat, which can reduce overall urban temperatures and also lead to a decrease in energy use.

Meanwhile, slums’ green advantage lies not only in their maximum density and minimum energy use, but also in their material resourcefulness. In Dharavi, 400 informal recycling units and 30,000 “ragpickers” sort more than 6,000 tons of trash every day, ensuring that, almost literally, nothing goes to waste. In Cairo, similarly, 70,000 garbage-pickers support themselves by collecting trash door to door; they recycle upwards of 80 percent of the waste they gather, while most Western garbage-collection companies only manage some 20 percent.

“[E]nvironmentalists have yet to seize the opportunity offered by urbanisation,” Brand has written, but they should — and soon. It is time, he says, to “green the hell out of the growing cities.”

“To Seize Opportunities, Megacities Need Clear, Tight Urban Planning.”


While existing and soon-to-be megacities hold enormous potential — for the environment, for the poor, for economies — important transformations are still needed to ensure that they can fully deliver on their inherent promise. To speed up these transformations (of infrastructure and services, among other things), some institutions and economists offer prescriptive policies and top-down planning recommendations. Many of these copy, or at least draw heavily from, Western urban-planning models. The Organization for Economic Cooperation and Development, for instance, argues that policymakers need to look to places like the Netherlands and embrace “compact city” policies (high residential density, little urban sprawl). More radically, Paul Romer of New York University’s Urbanization Project has proposed building major cities from scratch; called “charter cities,” these would be independent urban free enterprise zones, planned, built, and run in ways that economists and sociologists thought would be most efficient.

Foreign investment, guidance, and advice are not necessarily bad. But there is no one-size-fits-all approach to megacities in the developing world, and working from the bottom up is as important as working from the top down. “There are no historical precedents for such large cities,” explains Alain Bertaud, a senior research scholar at New York University. “Lagos, Mumbai, and Shanghai have to find their own solutions. None of them can pretend to become one day successful blown-up models of Copenhagen or Amsterdam.”

Finding better solutions begins with greater citizen participation. Satterthwaite argues that most policy decisions by international aid agencies and development banks are set up to support national, not local, governments. Thus, they are “not [directly] accountable to low-income groups,” especially in urban areas. As a better model, Satterthwaite points to the success of grassroots efforts like Shack/Slum Dwellers International, a federation of urban, community-based organizations in 33 countries that interacts directly with local governments to improve basic rights and access to services for people in slums.

Similarly, as part of efforts to provide better sanitation, education, and other necessities to megacities’ poor populations, governments, as well as international agencies, should seek to support and improve informal systems that citizens have already built — rather than replace them with whatever is new and “better.” There are numerous examples of how this can work. Since the early 1980s, the community-based Orangi Pilot Project in Karachi has trained activists, mobilized local funds, and invested over $1 million in toilets and sewer lines for more than 100,000 homes. The work has been so successful that the government has invested an additional $8 million to connect the project’s lines to the city’s main sanitation network. Sao Paulo, meanwhile, has incorporated informal recyclers into semiofficial cooperatives that operate around the city, and other Latin American cities have similarly integrated waste-pickers into their official sanitation systems.

Technology can also provide critical information about how megacities live and breathe — and how they can be improved. In Kibera, crowd-mapping platforms are enabling residents to map schools, pharmacies, water taps, and other essential landmarks through text messaging and GPS-enabled smartphones. The maps have in turn helped NGOs choose locations for things like new toilet facilities; they could help Nairobi’s government do the same. In Cairo, meanwhile, Bey2ollak, a crowd-powered traffic information app (with around 1 million registered users) allows commuters to post real-time information about the city’s traffic. One local paper recently called the
“more essential to traffic than traffic lights.” The government could use this existing data to better understand the city’s traffic patterns and work with experts to develop new systems for managing the chaos.

Megacities, then, already contain many of the ingredients for their future growth and change. While governments may look beyond borders for some support, their first stop should be with the people who know the nooks, crannies, and other intricacies of these cities best.

“Sadly, Megacities Need Governments That They’ll Never Have.”


Harnessing citizens’ input, informal economies, and bottom-up innovation requires good governance, and a deep concern among many development experts is that the relevant political leaders and institutions are often too corrupt or weak (or both) to get the job done. Romer and a colleague write that urbanization is peaking in places where “the capacity to govern is still in short supply.” Urban policy expert Richard Florida, meanwhile, writes that many of the world’s megacities “lack both” competent governments and the money they need to govern effectively.

But the outlook isn’t so bleak. “It’s certainly true that managing megacities is incredibly hard,” says Glaeser, but it can be done well. Although political will, sometimes embodied in exceptional leaders, is an important ingredient here, that will and the policies it leads to can be produced and shaped by everything from simple economics to social pressure. Moreover, the private sector can play a critical role.

Consider Medellín, Colombia’s second-largest city. (It is considered a “megacity of the future” or “megacity of tomorrow.”) Two decades ago, Medellín was a city of violence, corruption, and dangerous cartels; today, it has been called the world’s most “innovative city.” Under the progressive leadership of Mayor Sergio Fajardo, the city invested heavily in parks, libraries, schools, and affordable public transportation (buses and cable cars), targeting poorer neighborhoods. According to one academic study, a cable car system installed in 2003, linking poor areas on Medellín’s surrounding hills to the city’s downtown below, reduced the murder rate in those areas by 66 percent in just five years.

Although he is a standout example — the New York Times called him “nonconformist” — Fajardo didn’t emerge out of nowhere. In the late 1990s, he formed the Citizens Commitment movement, an initiative of artists, intellectuals, and businesspeople focused on decreasing poverty, violence, and inequality. He ran unsuccesfully for office in 2000 before finally winning in 2003, with wide support garnered over time from Medellín’s middle class and poor. In other words, the seeds of Medellín’s improvements were planted at the community level and cultivated over several years before finally blossoming.

In some cities, businesses’ economic concerns have driven changes in governance. In the late 1990s, Mumbai’s private sector realized that poor infrastructure, services, and urban planning were hampering growth and limiting investment. Leaders in the sector, along with the Bombay Chamber of Commerce and Industry, formed Bombay First, a nonprofit initiative with the goal of making the city a better place to live, work, and invest. In 2003, their work led to “Vision Mumbai,” a report with recommendations for citywide improvements that have been endorsed by the local, state, and federal governments, as well as the World Bank. Bombay First now runs more than 40 urban improvement projects, and government officials chair two of the organization’s action committees, enabling direct communication between the private sector and policymakers.

Then there is Nairobi, where the government is making some urban-planning decisions based on institutional self-interest. The city’s transportation system has long been a nightmare: a semiformal, cartel-driven, fiercely competitive, and chaotic mix of over 20,000 small and large buses. Payments for rides are cash-based and split among owners, drivers, and conductors, making the whole system rife with corruption — and tax evasion. To fix this, Nairobi’s government is in the process of implementing new regulations stipulating that minibus drivers receive a basic salary and that vehicles be registered with savings and credit cooperatives. By July 2014, all minibuses, according to the government, must be cashless, using payment systems like smart cards and mobile money instead. In addition to enhancing transparency and accountability, once implemented, the new system will help the government collect taxes — theoretically to invest in better infrastructure.

Better governance in both existing and emerging megacities can come about in many ways, from political and nonpolitical actors. And this ability to adjust and adapt extends well beyond governments, down to neighborhoods, economies, and citizens. While the world should not minimize megacities’ legitimate development needs, it should view these cities as the resilient, growing organisms that they are. Anything less would be to discount the profound and positive impact they can have in the 21st century.

Jonathan Kalan is a journalist based in Kenya and Washington, D.C.

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