Today's "Mega-cities" are Overcrowded and Environmentally Stressed
We take big cities for granted today, but they are a relatively recent phenomenon. Most of human history concerns rural people making a living from the land. But the world is rapidly urbanizing, and it's not at all clear that our planet has the resources to cope with this relentless trend. And, unfortunately, most of the growth is occurring in urban centers ill-equipped for the pace of change. You've heard of the "birth dearth"? It's bypassing Dhaka, Mumbai, Mexico City and Lagos, cities that are adding population as many of their western counterparts contract.
The world's first cities grew up in what is now Iraq, on the plains of Mesopotamia near the banks of the Tigris and Euphrates Rivers. The first city in the world to have more than one million people was Rome at the height of its Empire in 5 A.D. At that time, world population was only 170 million. But Rome was something new in the world. It had developed its own sophisticated sanitation and traffic management systems, as well as aqueducts, multi-story low-income housing and even suburbs, but after it fell in 410 A.D. it would be 17 centuries before any metropolitan area had that many people.
The first large city in the modern era was Beijing, which surpassed one million population around 1800, followed soon after by New York and London. But at that time city life was the exception; only three percent of the world's population lived in urban areas in 1800.
The rise of manufacturing spurred relocation to urban centers from the 19th through the early 20th century. The cities had the jobs, and new arrivals from the countryside provided the factories with cheap, plentiful labor. But the cities were also unhealthy places to live because of crowded conditions, poor sanitation and the rapid transmission of infectious disease. As the Population Reference Bureau reports, deaths exceeded births in many large European cities until the middle of the 19th century. Populations grew, then, by continuing waves of migration from the countryside and from abroad.
From First World to Third
In the first half of the 20th century, the fastest urban growth was in western cities. New York, London and other First World capitals were magnets for immigration and job opportunity. In 1950, New York, London, Tokyo and Paris boasted of having the world's largest metropolitan populations. (Also in the top 10 were Moscow, Chicago and the German city of Essen.) By then, New York had already become the first "mega-city," with more than 10 million people. It would not hold on to such exclusivity for long.
In the postwar period, many large American cities lost population as manufacturing fled overseas and returning soldiers taking advantage of the GI Bill fueled the process of suburbanization. Crime was also a factor. As an example, riot-torn Detroit lost 800,000 people between 1950 and 1996, and its population declined 33.9 percent between 1970 and 1996. Midwestern cities were particularly hard-hit. St. Louis, for instance, lost more than half its population in the same period, as did Pittsburgh. Cleveland precipitously declined, as did Buffalo, Cincinnati, Minneapolis and many other large cities, emerging as regional players rather than world leaders.
Meanwhile, while many American cities shrank, population around the world was growing dramatically. In the 20th century, world population increased from 1.65 billion to six billion. The highest rate of growth was in the late 1960s, when 80 million people were added every year.
According to the "World Population Data Sheet," global population will rise 46 percent between now and 2050 to about nine billion. While developed countries are losing population because of falling birth rates and carefully controlled immigration rates (only the U.S. reverses this trend, with 45 percent growth to 422 million predicted by 2050), population is exploding in the developing world.
India's population will likely grow 52 percent to 1.6 billion by 2050, when it will surpass China as the world's most populous country. The population in neighboring Pakistan will grow to 349 million, up 134 percent in 2050. Triple-digit growth rates also are forecast for Iraq, Afghanistan and Nepal.
Africa could double in population to 1.9 billion by 2050. These growth rates hold despite the world's highest rates of AIDS infection, and despite civil wars, famines and other factors. Despite strife in the Congo, it could triple to 181 million by 2050, while Nigeria doubles to 307 million.
Big Cities Get Bigger—and Poorer
According to a 1994 UN report, 1.7 billion of the world's 2.5 billion urban dwellers were then living in less-developed nations, which were also home to two thirds of the world's mega-cities. The trend is rapidly accelerating. People and the Planet reports that by 2007, 3.2 billion people—a number larger than the entire global population of 1967—will live in cities. Developing countries will absorb nearly all of the world's population increases between today and 2030. The estimated urban growth rate of 1.8 percent for the period between 2000 and 2030 will double the number of city dwellers. Meanwhile, rural populations are growing scarcely at all.
Also by 2030, more than half of all Asians and Africans will live in urban areas. Latin America and the Caribbean will at that time be 84 percent urban, a level comparable to the U.S. As urban population grows, rural populations will shrink. Asia is projected to lose 26 million rural dwellers between 2000 and 2030.
For many internal migrants, cities offer more hope of a job and better health care and educational opportunities. In many cases, they are home to an overwhelming percentage of a country's wealth. (Mexico City, for example, produces about 30 percent of Mexico's total Gross Domestic Product.) Marina Lupina, a Manila, Philippines resident, told People and the Planet that she and her two children endure the conditions of city living (inhabiting a shack made from discarded wood and cardboard next to a fetid, refuse-choked canal) because she can earn $2 to $3 a day selling recycled cloth, compared to 50 cents as a farm laborer in the rural areas. "My girls will have a better life than I had," she says. "That's the main reason I came to Manila. We will stay no matter what."
Movement like this will lead to rapidly changing population levels in the world's cities, and emerging giants whose future preeminence can now only be guessed. "By 2050, an estimated two-thirds of the world's population will live in urban areas, imposing even more pressure on the space infrastructure and resources of cities, leading to social disintegration and horrific urban poverty," says Werner Fornos, president of the Washington-based Population Institute.
Today, the most populous city is Tokyo (26.5 million people in 2001), followed by Sao Paulo (18.3 million), Mexico City (18.3 million), New York (16.8 million) and Bombay/Mumbai (16.5 million). But by 2015 this list will change, with Tokyo remaining the largest city (then with 27.2 million), followed by Dhaka (Bangladesh), Mumbai, Sao Paulo, New Delhi and Mexico City (each with more than 20 million). New York will have moved down to seventh place, followed by Jakarta, Calcutta, Karachi and Lagos (all with mo
re than 16 million).
The speed by which some mega-cities are growing has slowed. Thirty years ago, for instance, the UN projected Mexico City's population would grow beyond 30 million by 2000, but the actual figures are much lower. Other cities not growing as much as earlier seen are Rio de Janeiro, Calcutta, Cairo and Seoul, Korea. But against this development is the very rapid growth of many other cities (in some cases, tenfold in 40 years) such as Amman (Jordan), Dar es Salaam (Tanzania), Lagos and Nairobi.
The rise of mega-cities, comments the Washington Post, "poses formidable challenges in health care and the environment, in both the developed and developing world. The urban poor in developing countries live in squalor unlike anything they left behind
In Caracas, more than half the total housing stock is squatter housing. In Bangkok, the regional economy is 2.1 percent smaller than it otherwise would be because of time lost in traffic jams. The mega-cities of the future pose huge problems for waste management, water use and climate change."
In Cairo, Egypt, the rooftops of countless buildings are crowded with makeshift tents, shacks and mud shelters. It's not uncommon to see a family cooking their breakfast over an open fire while businesspeople work in their cubicles below. The city's housing shortage is so severe that thousands of Egyptians have moved into the massive historic cemetery known as the City of the Dead, where they hang clotheslines between tombs and sleep in mausoleums.
By 2015, there will be 33 mega-cities, 27 of them in the developing world. Although cities themselves occupy only two percent of the world's land, they have a major environmental impact on a much wider area. London, for example, requires roughly 60 times its own area to supply its nine million inhabitants with food and forest products. Mega-cities are likely to be a drain on the Earth's dwindling resources, while contributing mightily to environmental degradation themselves.
The Mega-city Environment
Mega-cities suffer from a catalog of environmental ills. A World Health Organization (WHO)/United Nations Environment Programme (UNEP) study found that seven of the cities—Mexico City, Beijing, Cairo, Jakarta, Los Angeles, Sao Paulo and Moscow—had three or more pollutants that exceeded the WHO health protection guidelines. All 20 of the cities studied by WHO/UNEP had at least one major pollutant that exceeded established health limits.
According to the World Resources Institute, "Millions of children living in the world's largest cities, particularly in developing countries, are exposed to life-threatening air pollution two to eight times above the maximum WHO guidelines. Indeed, more than 80 percent of all deaths in developing countries attributable to air pollution-induced lung infections are among children under five." In the big Asian mega-cities such as New Delhi, Beijing and Jakarta, approximately 20 to 30 percent of all respiratory disease stems from air pollution.
Almost all of the mega-cities face major fresh water challenges. Johannesburg, South Africa is forced to draw water from highlands 370 miles away. In Bangkok, saltwater is making incursions into aquifers. Mexico City has a serious sinking problem because of excessive groundwater withdrawal.
More than a billion people, 20 percent of the world's population, live without regular access to clean running water. While poor people are forced to pay exorbitant fees for private water, many cities squander their resources through leakages and illegal drainage. "With the population of cities expected to increase to five billion by 2025," says Klaus Toepfer, executive director of the UNEP, "the urban demand for water is set to increase exponentially. This means that any solution to the water crisis is closely linked to the governance of cities."
Mega-city residents, crowded into unsanitary slums, are also subject to serious disease outbreaks. Lima, Peru (with population estimated at 9.4 million by 2015) suffered a cholera outbreak in the late 1990s partly because, as the New York Times reported, "Rural people new to Lima
live in houses without running water and use the outhouses that dot the hillsides above." Consumption of unsafe food and water subjects these people to life-threatening diarrhea and dehydration.
It's worth looking at some of these emerging mega-cities in detail, because daily life there is likely to be the pattern for a majority of the world's population. Most are already experiencing severe environmental problems that will only be exacerbated by rapid population increases. Our space-compromised list leaves out the largest European and American cities. These urban centers obviously face different challenges, among them high immigration rates (see companion story):
A Yale University graduate student, who served as a college intern at the U.S. Embassy in Jakarta, brought back this account: "Directly adjacent to the Embassy's high-rise office building was a muddy, trash-filled canal that children bathed in every morning. The view from the top floors was unforgettable: a layer of brown sky rising up to meet the blue—a veritable pollution horizon. In the distance the tips of skyscrapers stretched up out of the atmospheric cesspool below, like giant corporate snorkels. Without fresh air to breathe, my days were characterized by nausea and constant low-grade headaches. I went to Indonesia wanting a career in government, and left determined to start a career working with the environment."
Jakarta is one of the world's fastest-growing cities. United Nations estimates put the city's 1995 population at 11.5 million, a dramatic increase from only 530,000 in 1930. Mohammad Dannisworo of the Bandung Institute of Technology (ITB) says 8.5 million people live within the city's boundaries at night and an additional 5.5 million migrate via 2.5 million private cars, 3.8 million motorcycles and 255,000 public transportation vehicles into the city during the day. This daily parade of combustion engines clogs the city streets and thickens the air, making Jakarta the world's third-most-polluted city after Bangkok and Mexico City.
Rapid growth has become one of the capital city's greatest challenges, as migrants continue to pour into Jakarta from the surrounding countryside in search of higher-paying jobs. An estimated 200,000 people come to the city looking for employment every year. In the face of such growth, the city has been unable to provide adequate housing, despite repeated attempts to launch urban improvement programs. The Kampung Improvement Program (KIP), established in the 1980s, was initially highly successful in boosting living conditions for more than 3.5 million established migrants, but it has been unable to accommodate the persistent migrant influx. There is an acute housing shortage, with a demand for 200,000 new units a year unfulfilled.
As Encarta describes it, "In the 1970s, efforts failed to control growth by prohibiting the entry of unemployed migrants. The current strategy emphasizes family planning, dispersing the population throughout the greater [metropolitan] region, and promoting transmigration (the voluntary movement of families to Indonesia's less-populated islands). Jakarta is a magnet for migrants
[During the late 1980s] most were between the ages of 15 and
39 years, many with six years of education or less."
The UN reports that the city's drinking water system is ineffective, leading 80 percent of Jakarta inhabitants to use underground water, which has become steadily depleted. In low-lying North Jakarta, groundwater depletion has caused serious land subsidence, making the area more vulnerable to flooding and allowing seawater from the Java Sea to seep into the coastal aquifers. According to Suyono Dikun, Deputy Minister for Infrastructure at the National Development Planning Board, more than 100 million people in Indonesia are living without proper access to clean water.
Jakarta's environment has been deteriorating rapidly, with serious air pollution and the lack of a waterborne sewer. Jakarta officials have only recently begun to acknowledge the source of over half of the city's air pollution, and have begun to take action against automobile congestion. The Blue Skies Program, founded in 1996, is dedicated to updating the city's public and private transportation technology. The project's successes to date include an increase in the percentage of vehicles meeting pollution standards, a near-complete phasing out of leaded gasoline, and an increase in the number of natural gas-fueled vehicles to 3,000 taxis, 500 passenger cars and 50 public buses.
The Blue Skies Project is pushing Jakarta toward a complete natural gas conversion and is working towards the installation of dedicated filling stations, establishing a fleet of natural gas-fueled passenger busses, supplying conversion kits for gasoline-fueled cars, and creating adequate inspection and maintenance facilities.
Jakarta has acknowledged its traffic problems and undertaken both small and large scale projects to alleviate the stresses of pollution and congestion. The city has launched a "three-in-one" policy to encourage carpooling, demanding that every car on major thruways carry at least three passengers when passing through special zones from 4:30 p.m. to 7:30 p.m. The city has also undertaken the construction of a nearly 17-mile monorail system.
But if Jakarta really wants to alleviate its infrastructure problems, it has to work from within, says Gordon Feller of the California-based Urban Age Institute. "The mayor needs to create a partnership between the three sectors—the government, the local communities and the non-governmental agencies. The job of the mayor is to empower the independent innovators, not to co-opt or block them."
Dhaka had only 3.5 million people in 1951; now it has more than 13 million. The city has been gaining population at a rate of nearly seven percent a year since 1975, and it will be the world's second-largest city (after Tokyo) by 2015. According to a recent Japanese environmental report, "Dhaka city is beset with a number of socio-environmental problems. Traffic congestion, flooding, solid waste disposal, black smoke from vehicular and industrial emissions, air and noise pollution, and pollution of water bodies by industrial discharge
. Black smoke coming out from the discharge is intolerable to breathe, burning eyes and throats. The city dwellers are being slowly poisoned by lead concentration in the city air 10 times higher than the government safety limit."
Because of a heavy concentration of cars burning leaded gasoline, Dhaka's children have one of the highest blood lead levels in the world. Almost 90 percent of primary school children tested had levels high enough to impair their developmental and learning abilities, according to a scientific study.
Water pollution is already rampant. According to the Japanese report, "The river Buriganga flows by the side of the densely populated area of the old city. Dumping of waste to the river by
industries is rather indiscriminate
. The indiscriminate discharge of domestic sewage, industrial effluents and open dumping of solid wastes are becoming a great concern from the point of water-environment degradation."
Nearly half of all Bangladeshis live below the poverty line, able only to glance at the gleaming new malls built in Dhaka. Urbanization and the pressures of poverty are severely stressing the country's once-abundant natural resources. According to U.S. Aid for International Development (USAID), "Pressures on Bangladesh's biological resources are intense and growing."
They include:½Poor management of aquatic and terrestrial resources; ½Population growth; ½Overuse of resources; ½Unplanned building projects; and ½Expansion of agriculture onto less-productive lands, creating erosion and runoff, among other by-products.
Bangladesh's expanding population destroys critical habitats, reports USAID, causing a decrease in biodiversity. Most of Bangladesh's tropical forests and almost all of the freshwater floodplains have been negatively affected by human activities.
But despite all the negatives, there is a growing environmental movement in Bangladesh that is working to save Dhaka's natural resources. The Bangladesh Environmental Network (BEN), for instance, works on reducing the high level of arsenic in Bangladesh's water supply (more than 500 percent higher than World Health Organization standards), combats the country's severe flooding problem and tries to defeat India's River Linking Project, which could divert an estimated 10 to 20 percent of Bangladesh's water flow. Bangladesh Poribesh Andolon holds demonstrations and international action days to increase citizen awareness of endangered rivers.
International development projects are also addressing some of the country's environmental woes, including a $44 million arsenic mitigation project launched in 1998 and jointly financed by the World Bank and the Swiss Development and Cooperation Agency. The project is installing deep wells, installing hardware to capture rainwater, building sanitation plants and expanding distribution systems. A $177 million World Bank project works with the government of Bangladesh to improve urban transportation in Dhaka. Private companies from Bangladesh and Pakistan recently announced a joint venture to construct a waste management plant that could handle 3,200 metric tons of solid waste per day, turning it into organic fertilizer.
Mexico City is like an anxious teenager, growing up faster than it probably should. That phenomenon manifests itself in awkward contrasts: Sports cars zipping down crowded streets, choked with air pollution; a Wal-Mart rising against a skyline of the ancient ruins of Teotihuacan; and trendy designer knock-off bags lining the walls of a grungy street stall.
The locale has long been a cultural hub—the ancient Aztec capital of Tenochtitlãn, where Mexico City now stands, was the largest city in the Americas in the 14th century with a population of about 300,000. When the Spanish razed Tenochtitlãn they erected Mexico City in its place, though a smallpox epidemic knocked the population back to 30,000. Mexico City served as the center of Spain's colonial empire during the 1500s, but the modern-day metropolis only began to materialize in the late 1930s when a combination of rapid economic growth, population growth, and a considerable rural migration filled the city with people.
The larger metropolitan area now engulfs once-dist
inct villages and population estimates range from 16 million to 30 million, depending on how the city's boundaries are drawn. Regardless, Mexico City is now widely considered the world's third-largest city, and still growing; birth rates are high and 1,100 new residents migrate to the capital each day.
With so many people crammed into a closed mountain valley, many environmental and social problems are bound to arise. Mexico City's air was ranked by WHO as the most contaminated in the world in 1992. By 1998, the Mexican capital had added the distinction of being "the world's most dangerous city for children." Twenty percent of the city's population lives in utter poverty, the Mega-Cities Project reports, 40 percent of the population lives in "informal settlements," and wealth is concentrated in very few hands.
A combination of population, geography and geology render air pollution one of the city's greatest problems. WHO studies have reported that it is unhealthy to breathe air with over 120 parts per billion of ozone contaminants more than one day a year, but residents breathe it more than 300 days a year. More than one million of the city's more than 18 million people suffer from permanent breathing problems.
According to the U.S. Energy Information Administration, "Exhaust fumes from Mexico City's approximately three million cars are the main source of air pollutants. Problems resulting from the high levels of exhaust are exacerbated by the fact that Mexico City is situated in a basin. The geography prevents winds from blowing away the pollution, trapping it above the city."
The International Development Research Center has observed that "despite more than a decade of stringent pollution control measures, a haze hangs over Mexico City most days, obscuring the surrounding snow-capped mountains and endangering the health of its inhabitants. Many factors have contributed to this situation: industrial growth, a population boom and the proliferation of vehicles." More than 30 percent of the city's vehicles are more than 20 years old.
Solid waste creates another major problem, and officials estimate that, of the 10,000 tons of waste generated each day, at least one quarter is dumped illegally. The city also lacks an effective sanitation and water distribution system. According to the United Nations, "Urbanization has had a serious negative effect on the ecosystem of Mexico City. Although 80 percent of the population has piped inside plumbing, residents in the peripheral areas cannot access the sewage network and a great percentage of wastewater remains untreated as it passes to the north for use as irrigation water."
Perhaps three million residents at the edge of the city do not have access to sewers, says the Mega-Cities Project. Untreated waste from these locations is discharged directly into water bodies or into the ground, where it can contaminate ground water. Only 50 percent of residents in squatter settlements have access to plumbing, and these residents are more likely to suffer from health effects linked to inadequate sanitation. Furthermore, Mexico City is now relying on water pumped from lower elevations to quench an ever-deepening thirst; as the city continues to grow, the need for water and the politics surrounding that need are likely only to intensify.
Mexican industry is centered within the city and is primarily responsible for many of the city's environmental problems as well as for the prosperity that certain areas have achieved. Mexico City houses 80 percent of all the firms in the country, and 2.6 million cars and buses bring people to work and shop in them. Sandwiched in between slums and sewers are glitzy, luxurious neighborhoods and shopping centers, as chic as any in New York or Los Angeles.
The streets of the Zñcalo, a central city plaza modeled after Spanish cities, serve as Mexico City's cultural hub. Unwittingly, the plaza has become one of the economic centers as well. Most job growth in Mexico occurs in the underground sector—in street stalls that cover every square inch of sidewalk space, women flipping tortillas curbside, and kids hawking phone cards or pirated CDs to passersby. Despite efforts to clean up activities that are illegal or considered eyesores, street vendors make up an enormous part of Mexico's job force and, according to the Los Angeles Times, are primarily responsible for keeping the official unemployment rate below that of the United States.
While problems abound, the city is doing its best to find solutions. Bicycles are the new grassroots rage, carrying everything from tentative tourists to head-high deliveries of Coca-Cola and fresh-baked bread. The city has had a thriving light rail system for years, with nine lines, 75 miles of tracks and more under construction. Neighborhood groups band together to build houses, remove trash and cut down on crime.
Volunteers also bring hope to many of the bleakest parts of the city. San Francisco has long served as a "partner" city to Mexico City through the nonprofit program Partners of the Americas. Through this program, Bay Area residents have worked with a counterpart committee in Mexico City and volunteered to teach English, bring medical supplies and develop micro-enterprises. The program has also developed numerous exchanges—in arts, economics, forestry and education, among others—that benefit citizens on both sides of the border.
Tom Gaman, a California forester and the Secretary of the San Francisco/Mexico City partnership, hopes that population growth will decline as economic conditions improve in the areas. He says of his many trips south, "Every time I go there I feel renewed in hope
the relevant issues that are so foreign to us Yankees are front and center in Mexico City."