One of the biggest threats to sustainability is that for many countries which are urbanising rapidly, for example India and China, a Westernised style of city may be followed – meaning a city dominated by cars and increasing ‘edge' developments for housing and services.
The ‘doughnut' model of an empty city centre and rapidly growing fringe has led to efforts to curb such developments by many authorities with the revitalisation of the city centre through prestigious retail and leisure redevelopments on brownfield sites. Examples are La Defense in Paris, West Quay in Southampton or Docklands in London.
Cities will not evolve into a sustainable form since there are so many different groups involved – speculators, individuals, pressure groups and so on. Planning and proactive management is critical to resolve differences in opinion and to safeguard minority social groups – but it needs strict political resolve!
Curitiba is a city of approximately 1.6m people situated in southeast Brazil. Its 1940 population of 120,000 almost quadrupled by 1965 – since when it has trebled to its current size. Industrialisation and exponential growth meant the city was faced with the same environmental, social and economic problems of other developing world urban areas – unemployment, slums, pollution and congestion.
The factor which makes it stand out as a model of ‘voluntary sustainability' is the vision and efforts of its mayor Jaime Lerner. He and his government have achieved higher levels of quality of life for the residents of the city by creating a city 'more intelligent and humane'. This is despite scarce urban resources. Curitiba's success has been largely dependent on the use of appropriate technology including the following:
Two-thirds of Curitibans used public transport by the 1990s – with 25 percent less congestion and noticeably cleaner air than cities of similar size. Sophisticated bus services dominate, acting like railways with 1.3 million people using the system daily. There is integration between the different forms of transport.
Recycling in Curitiba is now so advanced that two thirds of the city's daily waste is processed. Curitiba was awarded the highest environmental prize in 1990 by UNEP, and since its start in 1989 the recyclable waste scheme has accomplished the separation of 419,000 tons of recyclable waste – the equivalent of 1,200 20-storey buildings creating 280 square metres of trash each.
Low tech solutions
An unusual use of more low-technology methods is the 21-million square metres of parks, woods, gardens and squares within the city. Such recreational facilities enhance the quality of life. Most of Curitiba's parks, called linear parks, are located along river banks and in valley bottoms. They help prevent illegal occupation and shanty town growth and reduce misuse as landfill sites. The park lakes are used to hold back floods and function as water flow regulators during the rainy season. The environment itself is the ‘technology tool'.
List the types of technology used in the transport, recycling and energy-efficiency policies.
What other aspects must be considered in the goal of creating a more sustainable city?
Consider greenspace and community involvement among other issues.