Water Storage Capacity Shrinking as Dams Silt Up
The reservoirs of the world are losing their capacity to hold water as erosion brings silt down to settle in behind dams, according to the chief of the United Nations Environment Programme (UNEP).
Speaking to the Bonn International Conference on Freshwater yesterday, UNEP executive director Klaus Toepfer said that siltation is reducing the capacity of the world's reservoirs to hold water a result that is hastened by the clearcutting of forests.
"The issue of dams can arouse strong passions on both sides," Toepfer told the delegates. "Some people are very much in favor of building dams and others are vehemently against. However, what we are talking about here is the state and fate of the existing stock of dams and reservoirs on whose waters billions of people depend for not only irrigation and drinking water, but also for industry and the production of hydroelectricity."
Toepfer, a former German environment minister, advised careful management of the world's stocks of fresh, drinkable water. "It would seem prudent and sensible for us to manage the existing stock in the most sustainable way possible. Otherwise we face increasing pressure on natural areas with water, such as wetlands and underground aquifers, with potentially devastating environmental consequences to wildlife and habitats," he said.
In response, UNEP has launched a new Dams and Development Project (DDP), to address siltation and other serious environmental effects of dam development.
Based in South Africa, the Dams and Development Project, known as the DDP Unit, is a follow up to the work of the World Commission on Dams, publisher of an in-depth report on the environmental impact of large dams in November 2000.
The new DDP Unit has secured funding and pledges of over $2.5 million from the governments of Germany, the Netherlands, Sweden, Switzerland and the United Kingdom. Sustainable management of reservoirs will take a central role in its work.