A new study suggests that systematic overuse of water by two hydroelectric dams has decreased the level of water in Lake Victoria by at least two meters between 2000 and 2006 and that this drop was not influenced by weather. "The two dams, both located at the outlet of Lake Victoria in Uganda, have been using water at a rate of 20 to 50 percent above the allowable discharge agreed by Uganda and Egypt in 1957." As you can imagine, 2 meters over a lake that is almost 70,000 square kilometers is quite a bit of water. This has impacts on surrounding wetlands, the animals that use those as refuges (such as juvenile tilapia) and the people that live in the region.
A key staple of the local population living along the lake's shores, this loss of the tilapia fish threatens the food security of people depending on the lake in Uganda, Kenya and Tanzania. In the long term, the commercially fished Nile Perch, which feeds on smaller fish such as tilapia, could also be affected.
If overdrawing of water leads to permanent drying of these wetlands, the implications could be far-reaching, with large-scale eutrophication of the lake, exacerbation of invasion by the non-native water hyacinth, and accelerated global warming as the dried papyrus and its peat are burned to claim land for agriculture, duplicating the disastrous forest and peat fires in Indonesia.
We must avoid these consequences at all cost. The hydroelectric dams should not use more water than what has been determined scientifically to be a safe level of use. ::Science Daily