Environmentalists have mainly opposed dams, which flood forests, endanger certain species of animals and plants and displace inhabitants. Opponents of dams are calling for a complete evaluation of dams' ecological impacts. The newest attempts to make dams more environmentally friendly don't seem to be changing the opinion of their harshest critics.
Belo Monte project in Brazil has recently became a subject of dispute. Brazilians plan to build one of the world's largest dams on the Xingu River. The new water reservoir would flood 400 square kilometers of forest, killing the local flora and fauna, and probably releasing huge quantities of methane.
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