In 2008, for the first time in history, more than half the global population lived in cities. By 2030, some 5 billion will live in cities, and by 2050 that could rise to 7 billion. In Africa and Asia, the number of city dwellers is expected to double between 2000 and 2030.
No country has developed economically without urbanizing. People who move to cities have fewer children than those who remain in the countryside. But today’s cities tend to sprawl unplanned across the landscape, particularly in the poorer parts of the planet, where newcomers build huts and shanties on dangerous land, where it is hard to bring in services such as sewerage and electricity.
Cities must be planned more systematically and holistically to take advantage of economies of scale and limit their ecological footprints – easier to do when people live closer together. This means building smart transport networks, in which cars, trains, subways, bikes and walkways are all part of one interconnected system. It means using combined heat and power, recycling water and wastes, and bringing nature into cities – in parks, gardens, city farms and reserves. The systemic approaches required are not just a question of mechanics and infrastructure, but also of human behaviour and political systems. Many of the solutions will involve allowing slum dwellers and new arrivals to participate more in planning city growth.
