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Why big dams don’t work

Yesterday, Mike Muller argued on chinadialogue that China’s investment in dams is good news for Africa. Here, Lori Pottinger writes that large dams are costly and destructive, but Chinese experience in renewables still has a lot to offer.

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The record of Africa’s large dams is one of widespread environmental destruction to the continent’s major river systems, upon which millions of people depend for their livelihoods; forcible resettlement and human rights abuses; corruption and cost overruns.

Large dams across the continent have left a trail of "development–induced poverty" in their wake. Project benefits have been consistently overstated and inequitably shared. Africa’s large hydropower dams also disproportionately benefit industry and high-income groups, and have done little to reduce energy poverty. Finally, because African energy sectors are already excessively dependent on large-dam hydropower for electricity supply, and because the majority of Africans depend directly on rivers for their livelihoods, big dams are increasing the continent’s vulnerability to climate change

Chinese banks and companies are heavily backing dam construction in Africa, and have been involved in some very troublesome projects – including the Merowe Dam in Northern Sudan, whose reservoir displaced 50,000 farmers from their lands near the fertile Nile River to harsh desert resettlement camps; the 185-metre high Tekeze Dam in Ethiopia, which experts believe will silt up so fast the project will quickly become unviable; and now the Gibe III Dam in Ethiopia, considered Africa’s most destructive dam project, which will dry up Kenya’s Lake Turkana, the world’s largest desert lake, and impact half a million indigenous people in two countries.

China's policy of "non-interference" in the other countries’ affairs has resulted in Chinese support for African dam projects marred by state-sponsored violence and other human-rights violations; major environmental destruction; and a lack of transparency in every respect.  The majority of Africans rely on the natural environment for their livelihoods; choosing to build more large dams in Africa will cause greater ecological degradation, damage livelihoods and diminish quality of life for many.

Africa clearly needs energy and water-supply development. But the type and scale of development necessary to meet the needs of the poor is considerably different to what is generally being planned for the continent. African governments are seeking funding for billions of dollars worth of large hydropower proposals and the expansion of transmission lines serving primarily urban and industrial areas. Yet 80% of Africa’s population lives in rural areas far from the grid. Similarly, big storage dams are a costly and inflexible response to the needs of the huge number of people now without a safe water supply in Africa. A new path is needed.

Too big to fail?

Large dams are often the major focus of energy development in many poor countries, which can lead to an unbalanced and risky energy supply, increased corruption, and huge debt burdens. Worse, these projects often do little to increase energy access, because the bigger challenge is to bring electricity lines to the rural majority, who live in low-density villages far from national grids, and who cannot afford to use enough electricity to justify the connections.

For example, the Mphanda Nkuwa Dam in Mozambique is expected to cost at least US$2 billion, in a country with a national income per capita of about US$360. Most of the dam’s electricity will be used by the aluminum industry and neighbouring South Africa.

The Democratic Republic of Congo (DRC) has one of Africa’s least functional governments, but hopes to build the world’s largest dam, the Grand Inga, which could produce twice the power of China’s Three Gorges Dam. This mega-dam is expected to cost at least US$80 billion, in a country with an average national income of US$106.  The dam’s electricity could be exported as far away as Europe, yet there is no viable plan to increase energy access in the DRC from this project.

While countries generally get richer as they increase their use of modern energy, the trend goes the other way for countries that depend on hydroelectricity. Of the world’s 40 richest countries, only one is more than 90% hydro-dependent; of the world’s 40 poorest, 15 are more than 90% hydro-dependent, and many of these are in Africa. Numerous hydro-dependent African countries have suffered drought-induced blackouts and energy rationing in recent years.

Climate change is now altering hydrological cycles, which means that historical data is no longer a reliable predictor of future hydrological patterns. Many sub-Saharan countries are already over-dependent on hydropower for their electricity, and many areas have experienced increasingly crippling droughts that have sidelined hydropower production and cost billions in lost production every year.

The Nile River provides just one example of a river basin vulnerable to climate change that is also seeing huge growth in large hydro dams. In its 2001 report, the Intergovernmental Panel on Climate Change stated that in the Nile River Basin, there has been “a reduction in runoff of 20% between 1972 and 1987, corresponding to a general decrease in precipitation in the tributary basins calculated … In recent years there have been significant interruptions in hydropower generation as a result of severe droughts.”

Energy security means hydro-heavy African nations should diversify power generation away from large hydropower, rather than deepening their dependency. Diversifying the energy sector would help the continent’s climate-adaptation efforts in several key ways: it would de-emphasise reliance on erratic rainfall for electricity; reduce conflict over water resources; and protect river-based ecosystems and the many benefits they bring. Similarly, most Africans would benefit more from a localised water supply and improvements in their rain-fed agricultural systems, rather than a massive increase in big dams for water supply and irrigation.

A better path

Africa is ripe for a major, decentralised power roll-out of renewables and small power plants, which would build local economies from the ground up, not the top down.

Energy activists in Africa are pressing for energy choices that directly alleviate the energy poverty of Africa’s poor; that reduce nations’ vulnerability to climate change; and that are transparently planned with public participation. Large hydropower dams do not meet the first two criteria, and have never yet met the last. 

Energy development that invests in the local energy sector and creates skilled jobs for Africans should be prioritised. Decentralised, renewable technologies such as wind, micro-hydro and solar power specifically allow for higher rates of job creation and technology transfer. For example, a 2003 report commissioned by South Africa’s Sustainable Energy and Climate Change Project conservatively estimated that if South Africa set a target of generating 15% of its energy from renewable sources by 2020, it would create 36,373 new jobs in the country’s energy sector – greater than the total employment of the national energy utility, Eskom.

Africa has world-class solar potential, a vast belt of clean geothermal reserves, strong winds, and great potential for micro-hydro and no-dam hydro. A 2012 report by the European Commission Joint Research Centre found that, for huge swaths of the continent, using solar power or micro-hydro would be cheaper than expanding national grid services. The continent’s wind power potential is also tremendous along its large coastlines. East Africa has the potential to generate 15,000 megawatts of geothermal energy.  But most of these resources remain almost completely untapped.

China has much experience with the kinds of solutions that would help Africa’s poor majority. Its experience in biogas digesters, solar panels and solar water heating, clean stoves and wind turbines would bring much greater value for meeting Africa’s pressing development needs than a massive investment in destructive large dams.



Lori Pottinger is a campaigner on Africa for i
nternational Rivers.


Homepage image by International Rivers. Friends of Lake Turkana held barazas (public meetings) along the lake in the towns of Kalokol, Loareng'ak and Nachukui in Kenya where they worked with partner environmental groups within the regions to create awareness and update the communities about the developments with the campaign against Gibe 3 Dam on Ethiopia's Omo River.

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