Tapajós dams may cause death of fish , species loss, mercury contamination

Brazil plans to construct seven hydroelectric dams on the Tapajós River and its tributaries at a part of the Amazon known for its exceptional aquatic and terrestrial biodiversity. 

The São Luiz do Tapajós hydropower plant is the largest and first proposed dam.

An Environmental Impact Study (EIS) commissioned by the federal energy agency Eletrobrás in conjunction with the companies hoping to build the São Luiz do Tapajós dam says the project will cause a quick disappearance of habitat, loss of animals and reduction of their populations.

Still, the EIS concludes the dam will cause little environmental impact.

 In an independent analysis of the EIS commissioned by Greenpeace, scientists criticized the methodology and results of the document, noting that it failed to identify or misidentified

Because so little is known about Tapajós aquatic ecology, there is an urgent need for more studies before building begins, say experts.

The hydroelectric project could jeopardize commercial fish species, the pink river dolphin, giant otter and black caiman.

One fear is that the reservoir will concentrate dangerous levels of toxic mercury, poisoning fish and people.