Kenya’s plan to build dams on the River Mara and its tributaries poses a threat to the rich animal and plant life of Serengeti ecosystem that attracts tourists.
The habitat, comprising, Serengeti National Park in Tanzania and Masai Mara game reserve in Kenya has the River Mara as the only permanent source of water for the herds of wildebeest and other wildlife that migrate between the two countries.
Conservationists are concerned that the iconic ecosystem until recently threatened by a major new highway in Tanzania will now face a new peril from the dams.
Such dams could potentially reduce the amount of water flowing from Kenya to Tanzania and could spark a diplomatic spat should the EAC agreement be invoked in support or censure of the proposed projects.
Prof Eric Wolanski of James Cook University, Australia, says international efforts are needed to save the Serengeti as Kenya stands to reap all the economic benefits of the dams while Tanzania will remain saddled with environmental problems.
“Tanzania has to be involved as an equal partner with Kenya in the decision-making about managing the Mara and Ewaso Ngiro rivers. If that is not possible, then the financing of these dams must be stopped,” he said.
The River Mara depends on Kenya’s Mau Forest, whose catchment area already faces increased forest destruction and diversion of water for irrigation downstream. These could effectively dry up the river during times of drought.
The planned dams are Norera (10 metres high) and Mungango (30 metres). The Mara is formed after the confluence of the Amala and Nyangores Rivers. Further, water that makes up Masarua swamp will decline should Tanzania see through a plan to build the Borenga dam on the lower reaches of the River Mara past the Serengeti.
Environment lobby Serengeti Watch has issued an alert that the issue of the Mara is trans-boundary and that imperilling the river’s water could spell sure death for the Serengeti as a tourism destination and important vestige of the savannah ecosystem.
“An ecological disaster would befall the Serengeti ecosystem should a series of Kenya dams be built upstream of the Mara river,” said Berry Blanton, the lobby group’s media director.
He said the idea of Kenya’s proposed 65-metre tall Amala High Dam would divert water from the river and store it in another watershed in order to feed water back into the Serengeti during the dry season.
The Norera dam is to receive water from the Nyangores River that will also host the Mungango and Silibwet irrigation dams. Amala High Dam in the Mau Forest will have a tunnel to transfer water from the Amala to the Ewaso Ngiro River for power generation by Oletukat Olenkuluo, Leshoto and Oldorko dams.
The Oletukat Olenkuluo 140-metres, Leshoto (57 metres) and Oldorko (30 metres) will discharge water into Tanzania’s Lake Natron leading to diversion of the Mara river water to the lake and flooding of nesting sites of 75 per cent of the lesser flamingo.
The 10 metre high Norera dam on the Mara for irrigation is 30km upstream of Serengeti. Mungango (30 metre) and Silibwet (70 metre) dams on the Nyangores River are also for irrigation.
“None of these dams has been constructed yet, but the feasibility studies, except for Amala High Dam, were completed by 2016,” said Mr Wolanski in a study titled “The Serengeti will die if Kenya dams the Mara.”
He said the study, done jointly with Tanzania National Parks senior managers Bakari Mnaya and Mtango Mtihiko, concludes that the Serengeti will face ecological collapse during a major drought as Kenya’s dams will withhold water.
The Norera dam will release a minimum environmental flow (MEF) of 100 litres per second. This is one third of the Mara River’s MEF of 300 litres as recommended by the Lake Victoria Basin Commission of the EAC.
Water will flow through 30 km of land under intensive irrigation raising potential of Mara river to dry up upon entering the Serengeti. Norera is expected to receive 39 per cent of water from Nyangores river.
“Mungango and Silibwet dams will decrease low flow by 100 litres per second, but this impact was not included in Norera proposal and double chances this dam will not release MEF,” said Mr Wolanski.
Norera proposal is based on a mean annual flow calculated over 22 years of data but in a dry year the annual flow is only 51 per cent of the mean flow, hence in such a year the operator has only half of the water expected.
“Being short of water, the Kenyan operator has either to release the MEF for Serengeti and kill the irrigation fields and hurt local communities, or retain water for irrigation and kill the Serengeti. This becomes a local political decision, with Tanzania having no say,” the study says.
World Bank safeguard policies have been breached by the Norera proposal, which states incorrectly that the Mara River is not an international waterway and so, the development, therefore, does not affect forests.
The total annual storage and use would be 115 to 185 per cent of annual flow in a drought year, and the dams require more water for irrigation than is available, leaving nothing for minimum environmental flow.
The Amala High dam will lead to flooding and destruction of large expanses of the Mau forest and further decrease the Mara River dry season flows. In the dry season in a drought year, there will be zero MEF for Masarua swamp in Tanzania.