The proposal, for which preliminary engineering work has already begun, to build a dam across the Rufiji river at Steiglers’ Gorge, was the subject of a BTS seminar on 3 December 2018. The main speaker was Barnaby Dye of the University of Oxford, author of an environmental assessment for the World Wildlife Fund and a PhD thesis on the politics of dam building based on a case study of Steigler’s Gorge and two dams in Rwanda.
The Rufiji, by far the biggest river in Tanzania, is formed from the Ruaha, Kilombero and other tributaries. Not long after these river systems join, it enters Stiegler’s Gorge, about 100 metres deep. Creating a dam at this point has the potential to create a lake that is 100 kilometres long, and a power station that can generate 2,100MW of hydroelectricity.
There were proposals to build dams at this site as long ago as the 1900s. The project became a flagship in Tanzania’s Second Five Year Development Plan, 1969-74, and was promoted by commercial interests from the USA, Japan and especially Norway. But it was hard to justify the production of so much electricity, and the project remained dormant until it was revived after President Kikwete was elected in 2005. In 2012 the Brazilian company Odebrecht agreed to build it, but little followed. Then in 2017 President Magufuli ended the contract with Odebrecht and signed a deal with an Egyptian company, Arab Contractors, to build the dam and associated infrastructure. In contrast to the earlier contract, it does not require the contractor also to raise the money to build it.
There are doubts about how quickly Tanzania can use so much electricity, whether it can raise the very large sums of money required without paying extremely high interest rates, and there are many questions about the competence of the Egyptian contractor which does not appear to have a track record in the construction of large dams. There are also very serious concerns about the impact of the dam downstream. It will stop the river flooding and depositing its sediment (a nearly perfect natural fertilizer) on the floodplain, which is one of the main sources of Tanzanian rice and vegetables. It will also destroy the freshwater fisheries in the ox-bow lakes below the site of the dam, and greatly reduce the prawn fishery in the sea around Mafia island. It will also threaten the mangrove swamps, the biggest concentration of mangroves on the African coast. The dam, and its associated commercialization, will have a negative impact on the wildlife in the Selous Game Reserve and associated tourism. None of these points are new – they were all raised in the 1970s – but they are still valid. The dam can generate a lot of electricity, but many who live in or near the Rufiji flood plain will be worse off, and Tanzania will grow significantly less rice and other crops.
The second speaker, Antonio Andreoni of SOAS, put this into context. A reliable electricity supply is essential for economic development, and especially for industrialisation. However, since the 1990s electricity generation has been the subject of a series of corruption scandals. Given that these either produced no electricity or small amounts of high cost electricity, it is not a surprise that power cuts have continued and that TANESCO is no longer a company attractive to foreign investors. Hence the attraction of a single large project which will produce a surplus of power for many years to come. In contrast a series of gas, or solar-powered, generators would have many owners and complicated contractual issues would need to be resolved.
On the other hand the construction of a single huge dam means putting all the eggs into one basket, and there are serious doubts as to whether it can be delivered. So despite all the public statements to the contrary, there is as yet no certainty that the dam at Steigler’s Gorge will be built.
Barnaby’s slides are at https://www.slideshare.net/jachapman82/tanzanias-energy-sector-and-the-stieglers-gorge-dam
By: Dr. Andrew Coulson