Large-scale impacts of hydroelectric development

Abstract

The substantial size of some hydroelectric projects and the extensive total surface area covered by reservoirs globally require that research determining the impacts of these developments be done at ever-increasing spatial and temporal scales. As a consequence of this research, new views are emerging about the spatial extent and longevity of the environmental and social impacts of such developments. New findings challenge the notion of hydroelectric development as a benign alternative to other forms of power generation. This review examines the intertwined environmental and social effects of methylmercury bioaccumulation in the food web, emission of greenhouse gases from reservoirs, downstream effects of altered flows, and impacts on biodiversity, each of which operates at its own unique spatial and temporal scales. Methylmercury bioaccumulation occurs at the smallest spatial and temporal scales of the four impacts reviewed, whereas downstream effects usually occur at the largest scales. Greenhouse gas emissions, the newest surprise connected with large-scale hydroelectric development, are relatively short term but eventually may have important global-scale consequences. Limitation of biodiversity by hydroelectric development usually occurs at intermediate spatial and temporal scales. Knowledge developed from working at expanded spatial and temporal scales should be an important part of future decision making for large-scale hydroelectric development.

Roads and Dams: Infrastructure-Driven Transformations in the Brazilian Amazon

“…Among other large infrastructure projects, developing countries are pursuing hydropower infrastructure construction to improve their position in the global economy and as an important component of their socio-economic development to produce food, generate energy, employment, and income; and improve the overall quality of life of their citizens (Tortajada et al 2012;Richter et al 2010;Rosenberg et al 1997). Most of the developed world constructed large-scale hydroelectric dams up to the mid-1970s.…”

Run-of-River hydropower and salmonids: potential effects and perspective on future research

“…Over 800 000 dams have been built worldwide since the beginning of the 20th century, collectively influencing more than half of global runoff and intercepting 25% of naturally transported sediment (Vörösmarty and Sahagian 2000;Jackson et al 2001;Pittock and Hartmann 2011). Storage dams retain water for extended periods in reservoirs and subsequently release it at times that can be out of phase and frequency with NFRs (Rosenberg et al 1997;Murchie et al 2008). Such deviations from NFRs cause flow alterations that have well-documented consequences for river geomorphology, continental runoff, riparian communities, and macroinvertebrate and fish populations (Nilsson et al 2005;Murchie et al 2008;Poff and Zimmerman 2010).…”

Blood sucking Diptera (Culicidae, Psychodidae, Simuliidae) in forest fragment under impact of dam in the borderland of Rio Grande do Sul and Santa Catarina states, Brazil

“…These modifi cations may alter communities composition and population dynamics of several organisms, including Diptera related to transmission of human diseases, like Culicidae (PAULA & GOMES, 2007), Psychodidae (Phlebotominae) (REZENDE et al, 2009) and Simuliidae (ROSENBERG et al, 1997). In the last decade, many dams were erased along the Uruguai river, however very few data about the Diptera fauna with medical importance as vectorborne disease in this region are available.…”