![]() Though the lake has long served these purposes, the extent to which people are relying on the lake is unprecedented. (Photograph courtesy USDA Foreign Agricultural Service.) Increased discharges of water from the dam for power production may be causing the water level of Lake Victoria to drop. Nalubaale Dam regulates the flow of water out of Lake Victoria and into the Nile River. Its fish are an important source of food, and the lure of the lake, the evasive source of the Nile, draws tourists to its shores. It provides an inexpensive way to transport goods between the three countries. ![]() The lake is a crucial resource to the more than 30 million people in Uganda, Tanzania, and Kenya who live near its shoreline. “You have to decide which economic use is going to take highest priority during dry periods.” With Lake Victoria, the choice is complicated. “Reservoirs have multi-uses, and economic value can be placed on these different uses,” says Reynolds. Regardless of the cause, the drop in water levels means that those who rely on the lake face some difficult choices. According to news reports in January 2006, Uganda’s Directorate of Water Development (DWD) reported that the primary cause for falling lake waters was the power company’s failure to adhere to the 1954 water release policy, but other government officials later denied these allegations, saying that the drought was the only reason water levels were falling. When water levels on Lake Victoria plunged at the end of 2005, news media began reporting that water officials and environmental groups had accused the power authority that operates the dam of taking more water than the policy allowed. Almost immediately, drought struck, and officials were faced with both less water to generate power and a rising demand for electricity. (NASA image by Robert Simmon, based on data provided by the USDA Foreign Agricultural Service.)īut in an effort to bring more power to its developing economy, Uganda expanded the Nalubaale Dam in 2000, adding the Kiira power station to the dam. Rainfall (dark green line) over Kisumu, Kenya, on the shores of Lake Victoria was modestly below average (light green fill) in the second half of 2005, but may not have been low enough to account for the large drop in lake levels. Since the treaty, the Nalubaale Dam has operated to keep water levels near 11.9 meters above the Jinja gauge, and for 50 years, the policy successfully maintained water levels in Lake Victoria. The policy, which was revised in 1964, ensured that the natural flow of the Nile River would not be impacted by the dam. ![]() The White Nile River is the only outlet from the lake, and since 1954, the Owens Falls Dam has controlled the flow of water out of Lake Victoria into the Nile according to the terms of a treaty between Uganda and Egypt. “Lake Victoria is operated as a reservoir,” says Reynolds. (NASA image by Robert Simmon, based on the National Park Service Natural Earth map.) Lake Victoria’s rain basin (black border) is small relative to the size of the lake, leading to rapid fluctuations in lake level. But drought alone may not account for the drastic drop in water levels on Africa’s largest lake. Drought gripped several regions in Eastern Africa and the short rainy season, from October to December, was even more dismal in the Lake Victoria region. Low rainfall accounts for some of the drop in water levels on Lake Victoria. For this reason, the lake is very sensitive to rainfall, its water levels jumping depending on how much rain falls in a particular year. But Lake Victoria does not get water from a broad land region most of its water comes from rain that falls directly over the huge lake. For most lakes, the rain that falls over a broad region flows into the lake through rivers, streams, and ground water. “Lake Victoria is unique because the lake is a large majority of its rain basin,” Reynolds explains. The leaps and plunges in water levels happen because of Lake Victoria’s hydrology. At the time of publication, it represented the best available science. This page contains archived content and is no longer being updated.
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