Africa’s 600-plus lakes are under unprecedented strain from rising populations and must be managed better if demand for fresh water is not to stir instability, a U.N. report published on Monday said.
Some lakes are actually shrinking due to deforestation, climate change or poor farming methods, evidence of the need for better cross-border cooperation to ensure access to life’s most precious resource, the U.N. Environment Program (UNEP) said.
The report, based on a comparison of contemporary satellite imagery of Africa’s lakes and satellite photographs taken over recent decades, was unveiled at the opening of an international conference on lakes in Kenya’s capital, Nairobi.
Experts say that on a continent where most people have no access to safe drinking water the study should serve as a strong warning about the need for better environmental policies.
“Africa’s freshwater supply, including lakes, is threatened by depletion of water resources through pollution, environmental degradation and deforestation,” said the report, called “Africa’s Lakes: An Atlas of Environmental Change”.
“High population in Africa is the major cause of degradation and pollution of most African Lakes, as every one exploits aquatic resources to make a living,” the report said.
Water by the numbers
According to the United Nations, two thirds of the rural population and a quarter of the urban population in Africa are without safe drinking water, while even more lack proper sanitation.
Up to 90 percent of Africa’s water is used in farming, of which 40 to 60 percent is lost to seepage and evaporation, says the UNEP Atlas.
Lake Victoria -- Africa’s largest freshwater lake, which provides fishing and transport for 30 million people -- has dropped by three feet in the past decade, the report said.
The report also details the rapid shrinking of Lake Songor in Ghana, partly due to salt production, “extraordinary” changes in the Zambezi river system after the building of the Cahora Bassa dam site, and the near 90 percent shrinkage of Lake Chad.
UNEP said the damming of rivers, in conjunction with the disposal of untreated sewage and industrial pollution, had reduced Africa’s fish catch, particularly in the Nile Delta and Lake Chad.
“The sustainable management of Africa’s lakes must be part of the equation. Otherwise we face increasing tensions and instability as rising populations compete for life’s most precious of precious resources,” UNEP chief Klaus Toepfer said.
An accompanying report on the quality of legal pacts governing access to lakes in Africa highlights several possible flashpoints of political instability, UNEP said.
The report, “Hydropolitical Vulnerability and Resilience along International Waters in Africa”, points to the Volta river basin in West Africa, shared between Benin, Burkina Faso, Ivory Coast, Ghana, Mali and Togo, as being a particular concern.
The study, by UNEP and the University of Oregon, says over the next two decades population levels are set to double in the basin to 40 million, causing a dramatic rise in demand for water.
Meanwhile, rainfall and river flows in the region have declined steadily in the past 30 years, with this partly linked to higher evaporation rates as a result of climate change.