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• The world's urban population is currently growing at four times the rate of the rural population. Between 1990 and 2025, the number of people living in urban areas is projected to double to more than 5 billion. If it does, then almost two-thirds of the world's population will be living in towns and cities.
  

• By 2030, it is expected that nearly 5 billion (61 per cent) of the world's 8.1 billion population will live in cities. An estimated 90 per cent of the increase will occur in developing countries.
  
  
  
  URBAN POPULATION IN INDUSTRIAL AND DEVELOPING REGIONS, SELECTED YEARS
  Population increase in developing country cities will continue to be the distinguishing demographic trend of the next century, accounting for nearly 90 per cent of the 2.7 billion people projected by UN demographers (in the medium growth scenario) to be added to the world population between 1995 and 2030. (Source: World Urbanisation Prospects - The 1996 Revision).
  

• Even the best-run cities are having problems coping with rapidly expanding human numbers and escalating needs. Cities in developing countries are growing on average by over 3 per cent a year, and the growth is fastest in the poorest regions.
  

• In East, West and Central Africa, cities are growing by 5 per cent a year, enough to double their populations every 14 years. In the overwhelming majority of these cities, population growth has far outpaced municipal services and up to 40 per cent of all urban dwellers live in squatter settlements and slums.
  

Children of Mexico City
© Mark Edwards/Still Pictures

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• There is a continuing trend towards ever-larger urban agglomerations. By the end of the 20th century, 261 cities in developing countries had populations over 1 million, compared with 213 in the mid-1990s.
  

• While in 1960, only New York and Tokyo had more than 10 million people, by 2000, there were 16 so-called "megacities" with at least 10 million inhabitants. Their number is expected to reach 21 by 2015, 18 in less developed regions and 10 of those in Asia. But by then only 5.2 per cent of the world's population will live in these cities, and only 8.7 per cent (623 million) is cities with over 5 million inhabitants.
  

• However, some previous projections of exploding growth have not been borne out - e.g. Mexico City, which is now not expected to grow to more than 20 million by 2015 - only 2 million more than in 2000. In Mexico family planning has been very successful and the fertility rate is now only a little over replacement.
  

• Urbanisation usually accompanies social and economic development, but rapid urban growth on today's scale strains the capacity of local and national governments to provide basic services such as water, electricity and sewerage.
  

• Squatter settlements and overcrowded slums are home to tens of millions, like the favelas that cling to the hillsides of Rio de Janeiro and the tombs used as homes by tens of thousands in Cairo's "City of the Dead". In some developing countries, notably in Africa, this growth reflects rural crisis rather than urban-based development.
  

• At least 600 million urban dwellers live in squatter settlements in housing of such poor quality and with such inadequate provision of water, sanitation, drainage and garbage removal that their lives and health are under constant threat.

Related links:

• Link to WHO - Healthy Cities
  

• Link to our topic on People & Cities
  

• World Urbanization Prospects: The 2001 Revision

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