Damming the rivers of the Amazon basin

More than a hundred hydropower dams have already been built in the Amazon basin and numerous proposals for further dam constructions are under consideration. The accumulated negative environmental effects of existing dams and proposed dams, if constructed, will trigger massive hydrophysical and biotic disturbances that will affect the Amazon basin’s floodplains, estuary and sediment plume. We introduce a Dam Environmental Vulnerability Index to quantify the current and potential impacts of dams in the basin. The scale of foreseeable environmental degradation indicates the need for collective action among nations and states to avoid cumulative, far-reaching impacts. We suggest institutional innovations to assess and avoid the likely impoverishment of Amazon rivers. The current and expected environmental consequences of built dams and proposed dam constructions in the Amazon basin are explored with the help of a Dam Environmental Vulnerability Index. Damming in the Amazon There are already more than 100 hydropower dams in place across the Amazon basin. They are not just a source of energy, but also of on-going contention between developers, government officials, locals and environmentalists. This Perspective explores the current and expected environmental consequences of existing and proposed dams in the Amazon basin, with the help of a Dam Environmental Vulnerability Index (DEVI). The authors quantitatively assess the vulnerability of different regions of the basin, and propose that an integrative legal framework is required to guide all nine stakeholder countries towards minimizing the negative socio-economic and environmental impacts of present and future dams.