Colombia’s population, estimated at 40.8 million, occupies an area of just over one million square kilometres. One of the key projects in the country has been the transformation of the water system for the capital, Bogota, which has been under way since 1995. Bogota previously enjoyed the distinction of having one of the most contaminated water systems in the world. Organic wastes flooded onto streets and into homes during heavy rains and industrial toxins, such as lead and mercury, were discharged into causeways and the irrigation channels and fields that produce the city’s food. Bogota health authorities record tens of thousands of cases of water-related illness each year.

To solve the problems, an extensive system of water distribution mains and sewage tunnels has been constructed and is expected to eventually ensure that the poor are encouraged back to areas of the city that have been under-populated because of serious sanitation deficiencies. A new US$32.3 million system of sewage interceptors and drains has ameliorated appalling conditions for 500,000 people in areas of the city like Verbenal and Minuto de Dios, where the sewage-laden Salitre River used to regularly overflow. Channels have been constructed to carry wastewater away and new embankments limit flooding.

The risk of water rationing in Bogota has also been reduced by the rehabilitation of a major water treatment plant and a 31km potable water pipeline. An alternative pipeline from the high mountain ‘paramos’ will be completed in 2002.

Work is also underway to restore Bogota’s wetlands, which are home to 12 native bird species and migrant warblers from North America. The wetlands play a critical part in regulating water levels and treating pollution, but had shrunk from an original 50,000 hectares to just 800 hectares by the early 1990s.

The wetlands are now recovering as part of the wider benefits from the World Bank’s US$145 million loan to rehabilitate the city’s water system. The sewer system now diverts pollution and wastewater away from five wetland areas, and the environmental authorities collaborate with local communities to remove sediment and invasive aquatic plants.

“These projects clean up neighbourhoods and offer healthy outdoor possibilities to people otherwise trapped in a congested city,” said Jaime Castilblanco, an adviser on environmental and social affairs at Bogota’s public Aqueduct and Sewer Company (EAAB), which is carrying out the projects. “They are helping to change attitudes, so that people protect their natural surroundings, rather than seeing them as resources to exploit.”

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