This article encompasses many of the arguments that GrandRiverKeeper Labrador has been making when opposing the Muskrat Falls development. Girven the anecdotal information about the negative impacts of the so-called “Churchill Falls” dam (damming of six rivers) for people living downstream into the estuary, bay and into the ocean south of the Grand River. The fish stocks declined causing disruption to the economic and social fabric of these settlements and communities.

Dr. Philippe Van Cappellen, Department of Earth and Environmental Sciences UNIVERSITY OF WATERLOO Click HERE for full article

Rivers act as reactive conduits connecting the continental and oceanic carbon (C) cycles, and all the available evidence suggests that river damming significantly changes the export of organic carbon (OC) to the ocean. Dam construction and closure modify the downstream transfer of OC and essential nutrients, and thus the trophic state of the river system and that of receiving water bodies, including lakes and nearshore marine environments. However, the global-scale changes in riverine OC fluxes due to damming remain poorly quantified.

There are an estimated 16 million dams worldwide, of which more than 50,000 are large, that is, 15 meters in height or higher. Together large dam reservoirs cover over 400,000 km², while their volume equals about seven times that of the world’s rivers combined. The first wave of systematic dam building started after the Second World War and peaked between 1960 and 1980. More recently, a second wave of dam building has been taking place, in large part to supply energy to emerging economies. By 2030, it is estimated that at least 3,700 new hydropower dams with generating capacities larger than one megawatt will be added to the global count, thereby increasing global hydroelectricity production by 70%.

Damming may well constitute the largest single anthropogenic alteration of the freshwater hydrological cycle. In 1970 around 17% of the global river catchment area drained into large dams, in 2000 this had increased to 27%, and by 2030 it could be as high as 36%. Following the completion of currently planned dams, by 2030 it is estimated that up to 90% of all rivers will be fragmented by one or more dams.

 This study therefore assesses the role of damming as a driver of global environmental change, with an emphasis on how damming changes the global biogeochemical cycles of C and nutrients. It presents a worldwide analysis of trends in riverine OC fluxes that explicitly accounts for reservoirs as a compartment of the C cycle on continents. With the upscaling approach used this study, damming is shown to significantly decrease the export of OC to oceans. Through its large impact on the delivery of riverine OC, river damming represents a major anthropogenic forcing on the trophic state and C balance of the coastal ocean. By modifying C cycling and the accompanying greenhouse gas exchanges along the land-to-ocean continuum, dams impact the Earth’s climate. Our analysis indicates that the age distribution of dams exerts an important control on global C sequestration by reservoirs, and therefore on the role of damming in ongoing and future climate change.

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Mega Dams create MEGA DAMAGE! Are you concerned about the Grand River and the impacts of hydro development? Follow our blog and stay tuned to the latest reports and studies on the subject! Grandriverkeeper Labrador Inc. monitors what’s happening and will keep you posted on topics of interest. Follow this link. https://blog.grandriverkeeperlabrador.ca/

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Our goal is to preserve and protect the water quality and the ecological integrity of the Grand (Churchill) River and its estuaries for present and future users and for posterity through actions of public awareness, monitoring, research, networking, intervention and habitat restoration. As such one of our key objectives is to bring awareness both locally and globally of the cumulative impacts associated with megadams that we become aware of through our research.

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