Independent Experts Find Amazon Dam Studies Don’t Hold Water

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A group of independent experts – including internationally renowned authorities on the Amazon – have found serious errors and omissions in the environmental impact assessment (EIA) for Brazil’s massive Madeira River hydroelectric project, a multi-dam scheme proposed for one of the Amazon’s most important tributaries. The experts found the EIA to be inadequate, and recommended that additional studies be undertaken to evaluate the project’s impacts.

The Madeira River covers about one-quarter of the Brazilian Amazon, and its basin is a treasure trove of biodiversity. The Madeira supports the life of an estimated 750 fish species (including important migrating species), 800 bird species, and other endangered rainforest wildlife, and is home to rubber tappers, Brazil nut gatherers, and fishermen.

The independent experts raised questions about how much land would be flooded, the project’s impacts on fisheries and sediment flows, and potential health impacts from the reservoir, among other issues. The studies were commissioned by the Rondônia state Public Attorney’s office, and financed by the consortium seeking to build the dams.

Brazil’s environmental protection agency, IBAMA, is currently making its final decision on whether or not the project is environmentally feasible, the first step in the dams’ approval process.

The Brazilian government is actively promoting the construction of Santo Antonio and Jirau dams on the Madeira River as part of a larger four-dam cascade to generate electricity and permit large commercial barges to navigate 4,200 km up the Madeira to its upstream tributaries in Peru and Bolivia. Critics say the project would not only affect the high biodiversity of the region, but that the Madeira waterway would spur the advance of soy plantations in the Amazon rainforest and surrounding tropical savannas.

Among the scientists consulted were José Tundisi, a specialist on freshwater bodies and reservoir management with the International Ecological Institute in São Paulo state, and his colleague, biochemist Takako Matsumura. Tundisi states that the EIA’s data on sediment accumulation in the reservoirs is “inconsistent” and “unreliable.” The Madeira carries one of the highest volumes of soil, sand, and clay of any river in the world. “Sediment studies should always be undertaken on the river basin level,” Tundisi advised.

IBAMA limited the study area to that stretch of the Madeira that the project proponents said would be flooded by the dams. Sediments carry nutrients that fertilize the floodplain and help provide biological conditions for diverse species to flourish. They are considered a problem for dam builders, because their accumulation behind dams diminishes their effective operational life.

Philip Fearnside, ecologist with the National Institute for Amazon Research (INPA), found that there was insufficient data to back up project proponents’ assertions that sediment accumulation in the reservoir would not affect the dam’s economic viability. He also found that Jirau Dam would flood a wider area than projected, extending into neighboring Bolivia.

Ronaldo Barthem, of the Goeldi Museum in Belém, and Michael Goulding, of INPA – arguably the world’s most preeminent experts on Amazon migratory fish species – warned that under certain conditions, the dams could lead to the extinction of ecologically and economically important fish species such as the dourada and babão. Besides blocking upstream migrations of adult fish, most larva and fry heading downstream would be ground up by the turbines.

Even the area to be flooded by the dam may have been seriously underestimated by the studies. Bruce Forsberg and Alexandre Kemenes, biologists with INPA, found that “the area flooded could be double that projected (529 sq km) by the project proponents … casting doubt on the results of all studies carried out to date.” Forsberg also examined the risk that mercury discarded into the river by gold miners would make its way into the food chain as a result of the dams, and found that no attempt was made to quantify how much mercury a riverbank dweller eating a daily diet of fish would ingest.

Other potential problems identified by the specialists include impacts on downstream lakes which are important fishing grounds, proliferation of vectors for the spread of malaria and other water-borne diseases, and the socio-economic consequences of the migration of tens of thousands of men to the region in search of work.

According to Roberto Smeraldi of Friends of the Earth, Amazonia, “The project would transform the entire western Amazon, but the government is treating it as if it had only local impacts.”

Impacts on Bolivia

The project’s potential flooding of Bolivian territory has raised concerns among communities in Pando and Beni provinces. In October 2006, representatives of communities and indigenous peoples in the border regions of Riberalta and Guayaramerín issued a declaration demanding that the Bolivian government “urgently intervene with the Brazilian government and international organizations, such as the United Nations, in defense of our territory, our rivers, and the plants, animals, and environment, as well as our way of life.” The declaration noted that the flooding caused by Jirau Dam would mean the loss of fertile floodplain soils and that stagnant waters upstream from the dams would affect the water quality and health of Bolivians.

As a result, on November 7, 2006, Bolivia’s Foreign Minister David Choquehuanca sent a letter to his counterpart at the Brazilian Foreign Relations Ministry, citing “concern over the probable ecological and environmental impacts” of the dams planned for the Madeira River. The letter stated: “Among the probable impacts will be the flooding of Bolivian territory by the dams’ reservoirs, which would affect not only the existence of the Amazon forest in the Madeira basin, rich in Brazil nuts, but also possibilities for future construction of dams to satisfy regional and local energy needs.”

Choquehuanca proposed that a binational commission be formed to evaluate the possible cross-border impacts of the Santo Antonio and Jirau dams. Bolivian environmental officials also convened technical and scientific experts to evaluate the Madeira River hydroelectric complex and its possible effects on their country.

In February, 2007, Bolivian President Evo Morales met with Brazilian President Luis Inácio Lula da Silva to re-negotiate prices for sale of Bolivian natural gas to Brazil. Despite the fact that Lula announced that the two countries would examine the feasibility of a bi-national dam on the Madeira, news reports indicate that Morales held firm on Bolivia’s position that further studies on the two proposed dams are needed, and that until these studies are undertaken, the projects should not go ahead.

Brazil’s top energy priority

Despite the critical issues raised regarding the potential extent of the dams’ impacts, Brazilian energy planners say that the Madeira dams are the country’s number one priority for expansion of electricity generation. The Mines and Energy Ministry has assured investors that the rights to build the Madeira complex will be tendered in June or July 2007.

Under the Lula government’s new multiyear infrastructure plan (called the “Program to Accelerate Growth”), such projects will receive favorable terms from Brazil’s National Economic and Social Development Bank (BNDES). The government also says that under new rules, BNDES will be able to finance up to 80% of the total cost of the projects. This would include not only a major part of the US$9 billion cost of the Madeira dams, but also a significant portion of the cost of constructing 2,500 km of transmission lines to connect the project with the national grid. The transmission line corridor is estimated to cost between $1.75 billion and $4.25 billion. Its environmental impacts have not yet been analyzed.