Big infrastructure works and impact on local indigenous population: case study of Ralco Dam and the Mapuche-Pehuenche of Alto Bio Bio, Chile

Mariachiara Di Cesare, London School of Economics and Political Science (LSE)
Alejandro Dussaillant, Universidad de Concepción

This paper investigates the relation population-environment-history, specifically the analysis of the impact of a infrastructural project, a dam for hydroelectric power generation, on the population affected – in its structure, dynamics, and development. The study focuses on the effect of the Chilean hydroelectric dam of Ralco built between 1999 and 2003 in the Bío Bío river, the second largest river of Chile, a watershed within two Chilean regions (highest in Mapuche population), of great cultural and historical importance, and habitat for 30% of Chilean endangered native vertebrates species. For the case of Chile and other developing countries, impacts of energy infrastructure on environment and local populations are poorly understood and insufficiently incorporated into environmental impact assessments, within a context of increasing energy demand (and in a climate change scenario) that needs to be balanced with historical and cultural roots. Specifically, Mapuche-Pehuenches were strongly affected by the Ralco project (displacement due to inundation, rupture of the traditional productivity system, change in the use of the land, damage to culture and sacred places, etc.). Microdata from census will be used for the Municipality of Alto Bío Bío, to analyze population trends, before (1992) and during (2002) the construction. We analyze three small communities according to the level of the impact (high, medium, low), defined as: displaced community (Comunidad “el Barco”), not displaced community (Comunidad Ralco-Lepoy), and community not affected by the dam (Comunidad Trapa-Trapa). In this way we have a case-control study that lets us analyze the effect of the hydroelectric on demographic changes. The second step of the analysis is based on a specific survey in the three communities on fertility and family behaviors, health condition, and individual perception of the project (focusing on connectivity). This information permits to evaluate the post Ralco dam effects.