Construction of the $2-billion Gibe III dam in Ethiopia could have harmful effects on one of Africa’s largest lakes, according to a study commissioned by the African Development Bank.
But in a March interview with London’s Guardian newspaper, the Ethiopian ambassador disputed the study’s conclusions.
The report says filling the dam’s 16.26-cu-kilometer reservoir would require massive removals of water from River Omo, which feeds Lake Turkana, Africa’s fourth-largest lake, in neighboring Kenya.
The storage volume is equivalent to one year’s inflow into the lake, according to Sean Avery, a Nairobi-based hydrologist who studied the impact of the dam project for the African Development Bank.
"Ultimately, the 6,400-square-kilometer lake could reduce to two small lakes. The picture that emerges from these predictions bears a striking resemblance to the recent disastrous history of the Aral Sea, which was once the world's fourth-largest inland water body," said Avery.
He predicts the lake level would drop up to 20 meters below the lake's natural water level if Ethiopia completes the project and goes ahead with the associated 175,000-hectare irrigated sugar plantation downstream of the Omo River Valley.
Berhanu Kebede, Ethiopian ambassador in London, told the Guardian in March that the dam “will store additional water to what is currently present in the system—water that hitherto would have been wasted—and will permit the rational management of this water in the basin.” He added that Lake Turkana would not lose “a considerable amount of water, as claimed.”
Gibe III is part of the Gibe cascade, a series of dams that includes Gibe I (184 MW), the Gibe II (420 MW), and the planned Gibe IV (1,472 MW) and Gibe V (560 MW). It is being constructed by Italian construction firm Salini Costruttori after engineering design by a consortium, Studio Pietrangeli, and supervision of ELC-COB by Italy’s ELC Electroconsult and France’s Coyne et Bellier.
Ethiopia says electricity to be generated from Gibe III would be sold to Ethiopia, Kenya, Djbouti and Somalia and could generate $2 billion a year, a major source in addressing its $8.5 billion budget deficit (as of 2013). The country also is negotiating a power-sale agreement with Yemen and South Sudan.
However, in an interview on April 13, Avery said these electricity generation and transmission project agreements were made without the benefit of Environmental and Social Impact Assessment (ESIA) studies.