Sustainable Development of Cities

The rapid growth of cities in the developing world puts them in the forefront of the struggle for improved living standards and protection of the environment. Since 1950 the urban population has more than tripled, from just over 750 million to about 3 billion, by 2030 some 5 billion people will live in cities. In the developing world the urban population is projected to double from 1.9 billion in 2000 to be just under 4 billion by 2030. Worldwide, about three-fourths of all current population growth is urban. Cities are gaining an estimated 55 million people per year – over 1 million new residents every week from in-migration and natural population increase within cities. In developing countries many cities are growing two or three times faster than population growth for the country as a whole. As cities grow ever larger, their impact on the environment grows exponentially. The UN coined the term megacities in 1970s to describe cities with 10 million or more residents. As recently as 1975 there were only five megacities worldwide. Currently, there are 19 megacities, of which c15 are in developing countries. By 2015 the number of megacities will grow to 23. Megacities have captured public interest because cities this large are unprecedented in history and because of the popular perception that human well-being will decline in such dense concentration of people.