The Belo Monte hydroelectric complex, Brazil, was approved in 2005 even though the environmental impact assessments required by law and the consultations with the affected populations were not carried out. The Brazilian public prosecutor's office ruled on multiple occasions that the authorisation was unconstitutional. Nevertheless, after a decade of legal attempts to block it, occupations, strikes and violence, Belo Monte will begin producing energy in November.

The facts. The Belo Monte dam sits on the Xingu river, the main tributary of the Amazon, and will be the third largest hydroelectric power station in the world. It has had repercussions for 25,000 indigenous people belonging to 18 ethnic groups. Its construction has been financed primarily by Bndes, Brazil's public development bank. According to Norte Energia, the consortium responsible for building the dam, Belo Monte will supply energy to 60 million people.

Environmental degradation. The Brazilian government maintains that hydroelectric power stations produce sustainable energy. And yet, in Brazil deforestation is on the rise, partly due to infrastructure developments in the Amazon region such as Belo Monte itself, which will submerge 516 square kilometres of rainforest. The diversion of 80 per cent of the Xingu river has already compromised water quality and decimated fish biodiversity, drastically changing the lives of indigenous communities.

Furthermore, the river's flow varies according to the season. The dam will therefore operate at an annual average of 40 per cent of its total potential, that is 11,000 megawatts. Given its inefficiency, further dams — four, according to government plans — will be built upstream to feed Belo Monte throughout the year.

Human rights violations. Indigenous communities, the Brazilian public prosecutor's office and the International Labour Organization (Ilo) all agree in denouncing the fact that the government has not observed the right to free, prior and informed consent of indigenous communities. This requires that populations be consulted on all matters that affect them and is enshrined in the Brazilian constitution, the United Nations Declaration on the Rights of Indigenous Peoples and Ilo Convention 169, of which Brazil is a signatory.

The Suspensão de segurança (security suspension), a legal mechanism dating back to Brazil's military dictatorship, has conferred the arbitrary power to override judicial rulings against Belo Monte. Moreover, the Brazilian public prosecutor's office has accused the government of having violated 55 terms of the contract drawn up with two thousand families — mostly indigenous — who have been forcibly evicted.

While thousands of people are being driven out, others are arriving in their droves. Since 2011, waves of migrants have come to work on the dam's construction, swelling the population of the nearest city, Altamira, by 150 per cent. The consequences have been overstretched services, crime and cultural disintegration. The surplus of workers has led many to resort to illegal deforestation and cattle farming, two of the main causes of Amazon deforestation.

Why the battle is still open. Although it is too late to stop the Belo Monte dam, Brazil still has time to pursue sustainable development. The other planned mega-infrastructure construction projects in the Amazon must be halted — for example, the plan to build more than a hundred dams on the Tapajós river. The growing mining activity driven by dams such as Belo Monte is a further scourge that must be curbed.

Every cloud has a silver lining. Thus, dozens of hydroelectric plants operating below capacity due to the drought affecting Brazil will be converted into solar parks. Despite Brazilian president Dilma Rousseff having shown herself at the forefront of the fight against climate change (see the recent agreement reached with Barack Obama), it remains to be seen whether she will honour that role at home too. If she opposes the Tapajós dam and mining activities in the Amazon, only then will we believe this is not merely a cosmetic move.

Translated by Camilla Soldati