As a construction worker in Botswana's booming capital city, Mpontshang Mokwe is hardly struggling for work these days.
"There are too many buildings," Mr. Mokwe says, hauling a long strip of lumber toward the most recent of his projects – guest quarters for yet another new home in Gaborone's Block 8 neighborhood.
Not long ago, Block 8 was all dust and thorn trees and scrubland. Today, it is pure sprawl, with ever-sprouting apartment blocks, single-family homes, and shopping centers. Wander through Block 8, chockablock with construction workers such as Mokwe, and it's not difficult to imagine how, over the past 15 years, the population of Botswana's capital has ballooned more than 50 percent to over 200,000. It is expected to grow to 500,000 by 2020.
This rapid population increase is not unique to Gaborone. According to a recently released UN report, "State of World Population 2007," (www.unfpa.org/swp/) there is mass migration across the globe from rural areas to cities, as well as natural population increase within cities themselves. By next year, the report says, more than half of the world's people will live in urban centers, placing unprecedented strain on land and city services. Much of this shift will take place in Africa – and in smaller cities more than big ones.
"The increase in urban population is happening worldwide," says Cheryl Hendricks, head of the southern African security program at the South Africa-based Institute for Security Studies. "But it's particularly strong for Asia and Africa. These are developing countries, and as development occurs there's always a shift from rural to urban areas."
The continent's sprawling megacities, such as Lagos, Nigeria, Kinshasa, Congo, and Johannesburg will absorb many of these new city-dwellers. Already, population pressures in these metropolises have city officials scrambling. In Johannesburg this year, for instance, there have been several riots in the crowded townships, with people protesting what they see as their government's inability to provide basic services such as water and electricity.
But according to the UN report, it is smaller cities such as Gaborone that will bear the brunt of the world's rapid urbanization. According to the study, more than 52 percent of urban-dwellers live in cities with fewer than 500,000 residents, and these smaller cities are growing far more than large ones.
Mark Collinson, a researcher with the School of Public Health at Johannesburg's University of Witwatersrand, gives several reasons for that trend: More rural residents are moving to smaller, regional centers; fertility patterns in smaller cities tend to resemble the larger-family countryside; people have heeded family members' warnings about the "big, bad" megacities.
"Crime and squalor might be higher in the big city, so people might be more attracted to live someplace like Nelspruit," Mr. Collinson says, referring to a small city in northeast South Africa. "Smaller cities might have better housing standards and living conditions."
But whatever the reason, the pattern is unmistakable.
"For the foreseeable future," the UN report says, growth in "the smaller cities will predominate."
This doesn't have to be a bad thing. Urbanization can make it easier for governments to provide schooling and healthcare for its citizens, the report points out, and sound city planning can help reduce a country's overall environmental degradation. While many smaller cities struggle with scant financial resources, they also tend to have greater flexibility in planning, space, and decisionmaking.
Take Gaborone. A drive around this orderly capital shows some of the challenges of a smaller city turning into a boomtown, but also how some government policies – such as providing land for impoverished newcomers rather than trying to send them back to the countryside – can help ease the transition.
It's not just city neighborhoods like Block 8 that are exploding in size here – the sprawl extends beyond Gaborone's original borders. Along the road toward the airport, for instance, a series of developments sits on what was once rich agricultural land. To the south, near the Mokolodi Game Reserve, new upscale housing perches along brown ridge lines, with sweeping views toward the Kalahari.
For years now, Botswana has been considered one of Africa's success stories: a democratic country with regular positive marks from anticorruption organizations, high literacy rates, and a steady income from diamond-mining that gets funneled back to citizens through various government programs.
When the first president of Botswana, Sir Seretse Khama, took office in 1966, he supported a law that made all of his country's developments mixed income, vowing to avoid slums of the kind found in neighboring South Africa, says Aloysius Mosha, a professor of architecture and town planning at the University of Botswana. Since then, the government has solidified a welfare and subsidy-based land system where, for the same property, wealthy residents pay a top price and poorer citizens pay a nominal amount. This means – in theory, at least – that all residents have access to land, with minimal segregation between income groups.
The government also cracks down on people who try to set up shacks without permission – an effort to discourage slums, Mr. Mosha says.
While the government acknowledges that its subsidy system is not sustainable forever, and that it can't stop all impoverished settlements, it continues to create city master plans – something that few other small cities in the region do. And these plans, Mosha says, include designation of significant swaths of land for planned, low-income housing.
"There are push and pull factors," says Mosha, "They know if they go to the urban areas somebody will take care of them. The population here has been so small, the country has money, and the subsidies have encouraged people to move into urban areas."