Environmentalists blame dams for draining L. Victoria

Uganda's hydroelectric dams are draining Lake Victoria, causing its water levels to dwindle drastically, environmentalists have said. Writing in the New Scientist magazine on Wednesday, Daniel Kull, a hydrologist with the United Nations International Strategy for Disaster Reduction in Nairobi, Kenya, said Uganda was using more of the lake's water than was agreed upon 50 years ago under an international pact. According to Kull’s calculations, the water level in the lake is almost half a metre lower than it should be, with water releases at Uganda’s Owen Falls and Kiira dams at almost twice the permitted rates. Lake Victoria, Africa's largest fresh water lake, is shared by the East African nations of Kenya, Uganda and Tanzania. It is one of the most highly populated areas in the world, and the surrounding basin is intensely cultivated. Water levels have plummeted since 2003, and are now at an 80-year low. Ugandan authorities dismissed Kull's conclusions and blamed an ongoing drought in the region for the lake's low water levels. "The impact of prolonged drought has been severe. All the lakes in the region have had declining water levels in spite of the fact that Kiira Dam is not connected to them," said Karisa Kabagambe, permanent secretary in the Ministry of Environment. Kabagambe said the reduced water levels are the result of a 10 percent to 15 percent decline in rainfall across the lake's catchment areas during the past two years. Kull, for his part, said the dams on Lake Victoria were as much to blame for the low water levels as the drought. He added that if the dams had operated as agreed, the drought would have accounted for only half the water loss. British engineers designed the Owens Falls dam to generate hydropower without disrupting the natural flow of the water from the lake. A formula known as the "agreed curve" was set, detailing the maximum water flow of between 300 cu.m. and 1,700 cu.m. per second, depending on the water level in the lake. According to engineers, the problems began in 2002 when Uganda finished building the Kiira hydropower complex in the eastern town of Jinja. "The second dam created a second outlet at a lower gradient than the natural weir [barrier], and it therefore drains more water than was naturally planned," said a water engineer in the works ministry who declined to be named. Kull estimated that over the last two years, the two Ugandan dams have released water at an average of almost 1,250 cu.m. per second - 55 percent more than is permitted given current water levels. A vital economic resource disappearing Lake Victoria is a valuable resource to the region, providing potable water, hydroelectric power and inland water transport. It supports many different industries, such as agriculture, trade, tourism, wildlife and fisheries. The lake basin serves as a major source of employment for an estimated 30 million people. Approximately three million people are engaged, directly or indirectly, in subsistence and commercial fishing, and more than 80 percent of the population is engaged in agricultural production as small-scale farmers and livestock owners. The low water levels have begun to affect the country's electricity supply. Uganda's capital, Kampala, has experienced unprecedented power cuts recently. The country has resorted to severe power rationing, with some areas having electricity for less than five hours in a day. Ugandan industrialists have predicted hard times ahead for the industrial sector, saying escalation in operation costs will force them to shut down, costing thousands of jobs. Abid Alam, chairman of the Uganda Manufacturers' Association, said his organisation was pushing for dialogue with the energy ministry to mitigate the problem. "We want the government to subsidise the cost of fuel so that industries can power their own generators, and the government should expediently increase thermal-electricity generation as stopgap measures," he said. Uganda has some hydroelectric potential along the River Nile, but only a fraction of it has been developed. Currently, the country's power demand is greater than supply, with fewer than 10 percent of the population having regular access to electricity. Many towns do not have any power supply, notably in the war-affected north.