In a new paper entitled "What future for lake Turkana: the impact of hydropower and irrigation development on the world’s largest desert lake", the Nairobi based hydrologist and consulting engineer, Dr Sean Avery, considers the impacts on the lake of river basin development in the Omo Valley. The paper is based on reports submitted by Dr Avery to the African Development Bank (2010) and to the African Studies Centre at Oxford University (2012).
What Future for Lake Turkana?
The Gibe III Dam, now being built in the middle basin of the Omo, will make possible large-scale commercial irrigation schemes in the lower basin. One of these schemes, now being implemented by the Ethiopian Sugar Corporation, will equal in extent the current irrigated area of Kenya. This will require a huge rate of water abstraction from the Omo, a transboundary river and the source of 90 per cent of Lake Turkana’s freshwater and accompanying nutrient inflow.
Lake Turkana diagram
The actual irrigation water demand will depend not only on the crop area to be irrigated but also on the overall efficiency of the irrigation system. Making the optimistic assumption of an overall irrigation efficiency of 60 per cent, the paper predicts that the sugar scheme alone will require well over 30 per cent of the Omo flow. This rises to almost 40 per cent if the remaining area already allocated to irrigation development in the Lower Omo is included. If the efficiency assumption is reduced to 45 per cent (the figure used by the Omo-Gibe Master Plan of 1996) the total water demand for projected irrigation development in the Lower Omo reaches over 50 per cent.
This would lead to a drop in lake level of over 20 metres (its average depth is roughly 30 metres), a more than 50 per cent reduction in its volume and biomass (total mass of living organisms) and a drastic fall in the productivity of its fisheries. Ultimately, the lake could reduce to two small lakes, one fed by the Omo and the other by the Kerio and Turkwel rivers. The picture that emerges from these predictions bears a striking resemblance to the recent disastrous history of the Aral Sea, a non-outlet lake in Central Asia which was once the world’s fourth largest inland water body.
Download the full report.
The Gibe hydroelectric project is one of a series of damming projects that have been undertaken by the Ethiopian government. The project is a public-private partnership planned as a 25 year national energy master plan of Ethiopia. The planned increase in power generation, however far exceeds domestic needs with the surplus which is estimated at 50 percent being exported to the neighboring countries including Kenya which the Ethiopian Electric Power Company (EEPCo) predicts to export 500MW to.
Download Gibe III Fact sheet and other documents here to obtain more background information pertaining to the Gibe III project.
The Gibe III threatens the biodiversity, livelihoods, and development of Northern Kenya, yet these potential risks have not been taken into account in the project planning by the Government of Ethiopia. The project has been opposed by local and international environmental and human rights groups and advocates. However, it was ultimately approved based on an incomplete Environmental Impact Assessment (EIA) that did not adequately take into account the perspectives of indigenous communities around Lake Turkana.
To find out more about the threats the Lake faces with its construction, click here
Despite the potential impacts of the dam on the lake’s ecosystem and livelihoods, Ethiopia has continued to pursue the project without an adequate environmental and social impact assessment (ESIA) or proper consultation with the Lake Turkana Basin communities. FoLT is therefore working to bring attention to the impacts which Gibe III Dam will have on the Lake Turkana region and peoples and to find lasting solutions to this social injustice.