More studies needed for Amazon dams

WWF 9 Jun 09;

La Paz, Bolivia - An international group of scientists has called for more studies into the impacts of large hydro-energy projects in the Amazon and other tropical regions.

The International Symposium held in Bolivian government seat La Paz looked at multiple studies, focusing on the Madeira river watershed, to assess required and prudent levels of environmental, social and economic evaluation of tropical dam projects.

“The main objective of the studies supported by WWF is to contribute to the fair and expected Bolivian Amazon development to be reached in a sound manner, especially considering enough elements not to jeopardize the ecosystem and its use irreversibly for future generations,” said Marcela Añez, Infrastructure Officer with WWF Bolivia.

The Madeira river is the Amazon’s main tributary and supplies the greatest quantity of water and sediments to the river. Research presented at the symposium showed that the Brazilian dams of Jirau and Santo Antonio would cause hydraulic and hydrological impacts in Bolivia, including an increased risk of floods.

The symposium, attended by scientists from Bolivia, Brazil, Ecuador, Peru and France, also heard an estimated that 80 percent of fish in the Bolivian Amazon are migratory, and some of the species with an important value from a commercial and subsistence point of view could be affected.

“Within the possible impacts are the gradual reduction in fishing, which could affect at least 16,000 Bolivian families whose livelihood depends on this activity,” said Paul Van Damme, from the FaunAgua Association.

Marc Pouilly, from IRD, also warned that “there is considerable data that is precise and which predicts that floods will occur as a consequence of the dams, which could affect the use of natural resources and increase diseases such as malaria, yellow and dengue fevers. It is very important to carry out further studies to estimate the extension of the area of the Bolivian Amazon that could be flooded, as well as the impacts in the dams’ nearby areas and downstream”.

Other impacts that have been observed in dams that are constructed in tropical areas is the increase in mercury in fish (in the reservoir and mainly down river), deforestation in the area along the power lines, contamination with herbicides to maintain these power lines, retention of sediments and erosion on river banks, according to Jean Remy Davée Guimaraes, from the Federal University of Rio de Janeiro (UFRJ).

In terms of socioeconomic impacts, Manuel Antonio Valdés, from the Rondonia Federal University (UNIR), added that, in the case of Brazil, 65 percent of the population that was visited in the area of the Madeira river (close to 1,100 families) as part of the research will very likely have the need to move, leaving behind their animals, crops, customs and ways of life in harmony with the river. Of these, only 30 percent have land property titles, which would make social compensation efforts difficult.

The event was coordinated by Jorge Molina of the Institute of Hydraulics and Hydrology at Andrés University (IHH/UMSA), the Institute for Research and Development (IRD) and WWF, the global conservation organization.

IHH, IRD and WWF have been supporting research and dissemination of technical information related to the possible impacts that might occur in Bolivia as a result of the construction of dams on the Madeira river in Brazil, aiming to provide input for stakeholders to be able to influence decision makers, minimize negative impacts and promote the development of sustainable energy infrastructure in the Bolivian Amazon. The scientists’ main concerns revolve around the sensitivity of the northern Amazon in Bolivia in regards to the dams, and the need for improved evaluations.