Towards sustainable cities

Posted: 26 January 2008

While many city governments face unprecedented challenges, a number of steps can make cities more livable and protect the environment. These include better urban planning, more public transportation, better sanitation and rational water use policies, energy conservation, urban farming, and waste recycling. In addition, slower population growth would ease pressures on cities and buy time to find solutions.

Better planning and public transportationIn many cities better planning, coupled to effective zoning of polluting industries and green belts, could improve the quality of life for urban residents and protect the environment. Effective city planning requires strong local government supported by active citizen groups working for improvements in the quality of life.

One of the best investments cities can make - both environmental and economic - is in efficient mass transportation systems. A good mass transportation system can create jobs by providing an affordable way for residents to reach places of employment. It also can greatly reduce pollution by reducing the demand for private vehicles. WHO estimates that about 700,000 deaths annually could be prevented in urban areas of developing countries if the three major pollutants - carbon monoxide, suspended particulate matter, and lead - were brought down to safe levels.

Providing water, improving healthMany cities in developing countries are growing so fast that they cannot manage the water supply. In developing countries as much as 70 per cent of the water pumped into cities is lost before it can reach consumers, leaking out of faulty water mains, pipes, and faucets or siponed off illegally by "water pirates".

Watercart, Burkina Faso. Credit: UN-Habitat

Cities can gain a great deal from adopting water conservation measures. A key to urban water conservation is pricing water to reflect its value as a scarce resource. Pricing water minimally or not at all encourages waste. Charging higher prices would not necessarily deny water to low-income areas, however. In Tegucigalpa, Honduras, for example, six neighbourhoods together approached the city water authority with a request to provide piped water. Consumers themselves paid for the water connections. Nevertheless, the price that households paid for water dropped because residents no longer had to buy expensive water from street vendors, and the quality of their water improved.

EU pilot programme on pollutionThe European Commission recently launched a US$ 43 million pilot programme in 14 major European cities to reduce traffic congestion. The programme uses a combination of incentives and disincentives, including fines for motorists driving into restricted areas, improvements in public transport, and reduced fares on buses and rapid rail systems during peak commuting times.

Conserving energyDeveloping country governments have far to go in encouraging more efficient energy use. Energy prices often drop dramatically for consumers when utilities invest in energy efficiency. More efficient energy use also is a good investment for utilities because it helps avoid the need to build costly power plants, and it reduces the amount of pollutants pumped into the atmosphere.

The "energy crisis" of the early 1970s caused a surge of energy efficiency measures in Europe and the US. By 1985 the use of more efficient household appliances, along with more stringent efficiency standards required in buildings, brought dramatic energy savings to US consumers and helped make it possible for US utilities to avoid building 350 megawatts worth of power plants. These innovations helped spawn a US$3 billion-per-year energy conservation industry, funded by the utilities, whose average payback time on investment in energy conservation was only about one year.

Urban farming and recyclingUrban farming helps feed city residents. It also helps protect the environment by reducing the need to bring in food. The UN Development Programme has estimated that about 800 million urban and peri-urban farmers produce over 15 per cent of the world's food. If city governments adopted explicit policies and incentives to encourage urban agriculture, the number of urban farmers would probably increase substantially.

Until the mid-1990s, when massive population growth and rising demand overwhelmed local food supplies, urban farmers in China's 18 largest cities were able to produce over 90 per cent of locally consumed vegetables and half of all the meat and poultry. Hong Kong still produces two-thirds of the poultry, half the vegetables, and 40 per cent of the fish it consumes. Singapore produces all of its meat and fish and one-quarter of its vegetables.

City squalor. Credit: UN-Habitat

Recycling-converting mountains of urban waste into new resources also makes sense both economically and environmentally. Economically, for every 1 million tons of solid waste, about 1,600 recycling jobs could be created in developed and developing countries alike, according to industry surveys. Recycling benefits the environment by saving natural resources and reducing the amount of trash in landfills or dumped into rivers, lakes, and oceans.

Family planningWorries about a global "population bomb" may have lessened as fertility rates have fallen in most developing countries. Nevertheless, the world's population continues to grow by 75 million people each year - almost all in developing countries. Urban areas are gaining about 60 million people per year. While fertility has fallen to replacement level in 59 countries - 15 of them in the developing world - about 1.6 billion people live in 46 countries where fertility averages between three and four children per woman. In 47 other countries with a combined population of about 795 million, the average woman has nearly five children (4.7).

Since the 1960s family planning programmes have played a key role - perhaps the key role - in slowing population growth in developing countries. Between 20 per cent and 50 per cent of the fertility decline in developing countries has come as a direct result of family planning programmes.

Today, for the urban areas of developing countries, meeting the family planning needs of city residents is a promising strategy not only to improve health but also to slow population growth. In particular, programmes can do more to reach the urban poor, including recent migrants, who live in areas that often have not been served well. By enabling people to have the number of children they want, family planning programmes can help make cities more livable today while, by slowing population growth, they help safeguard natural resources needed for the future.

Sources: Population Reports, Fall 2002. Meeting the Urban Challenge, published by Population Information Program of Johns Hopkins University.
World Population Prospects - the 2004 Revision.