Mitigation and Adaptation Strategies for Global Change

, Volume 10, Issue 4, pp 675–691

Do Hydroelectric Dams Mitigate Global Warming? The Case of Brazil's CuruÁ-una Dam


DOI: 10.1007/s11027-005-7303-7

Cite this article as:
Fearnside, P.M. Mitig Adapt Strat Glob Change (2005) 10: 675. doi:10.1007/s11027-005-7303-7


Hydroelectric dams in tropical forest areas emit greenhouse gases, as illustrated by the Curuá-Una Dam in the Amazonian portion of Brazil. Emissions include carbon dioxide from decay of the above-water portions of trees that are left standing in the reservoir and methane from soft vegetation that decays under anaerobic conditions on the bottom of the reservoir, especially macrophytes (water weeds) and vegetation that grows in the drawdown zone and is flooded when the reservoir water level rises. Some methane is released from the reservoir surface through bubbling and diffusion, but larger amounts are released from water passing through the turbines and spillway. Methane concentration in the water increases with depth, and the turbines and spillway draw water from sufficient depth to have substantial methane content. In 1990 (13 years after filling), the Curuá-Una Dam emitted 3.6 times more greenhouse gases than would have been emitted by generating the same amount of electricity from oil.


AmazoniaBrazildamsgreenhouse gas emissionshydroelectric damsreservoirs

Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  1. 1.National Institute for Research in the Amazon (INPA)ManausBrazil