Hydroelectric is not emission-free or clean. A Washington State University study on the effects of damming conducted in a central European impounded river revealed that the reservoir reaches are a major source of methane emissions and that areal emission rates far exceed previous estimates for temperate reservoirs or rivers. It showed that sediment accumulation correlates with methane production and subsequent ebullitive release rates. Results suggested that sedimentation-driven methane emissions from dammed river hot spot sites can potentially increase global freshwater emissions by up to 7%. Hydroelectric facilities need to acknowledge and account for the associated GHG emissions they produce.
 Maeck, A., DelSontro, T., McGinnis, D.F, Fischer, H., Flury, S., Schmidt, M., Fietzek, P. and Lorke, A., 2013. Sediment Trapping by Dams Creates Methane Emission Hot Spots, Environmental Science and Technology, 8130-8137, Online: http://www.dx.doi.org/10.1021/es4003907
Category Archives: Mercury
WWF-Canada and Nature Conservancy Support Adding Turbines to Non-powered Dams
It is challenging to understand the logic of a November 2021 CBC article that reports, “The Nature Conservancy and the World Wildlife Fund are two environmental groups that oppose new hydro dams because they can block fish migration, harm water quality, damage surrounding ecosystems and release methane and CO2. But they say adding turbines to non-powered dams can be part of a shift toward low-impact hydro projects that can support expansion of solar and wind power.” Whether it’s a new dam or an older retrofitted dam, they will result in the same negative impacts and produce the same amount of methane for 70 to 100 years or more.
Canada’s Freshwater in the 21st Century, 2014, Dr. David Schindler
June 18, 2014 — Water Institute Lecture Series and Faculty of Science Public Lecture Series
Dr. David W. Schindler, Killam Memorial Professor of Ecology, University of Alberta, retired.
Methylmercury – Impacts of Reservoir Flooding – Hydroelectric
Reservoirs represent a significant portion of the freshwater surface on the planet. In Canada, most reservoirs are constructed to provide stable water supply for the generation of hydro-electric power. Particularly in the relatively low topography of the Precambrian Shield, the creation of reservoirs often results in the flooding of large areas of former wetland and upland forest.
By the late 1970’s, researchers recognized that fish populations in many newly-flooded reservoirs were subject to significant increases in tissue concentrations of methyl mercury. Humans relying of these fish for regular food supply were at risk of developing mercury poisoning, which can result in severe damage to the nervous system. What was causing this mercury problem and how could it be mitigated? Continue reading
Experimental Lakes Research in Kenora Reveals just how Dirty Hydroelectric Really Is – Groundbreaking Information
Harper seals our fate on water and energy sustainability
The federal government states that Fisheries and Oceans Canada no longer need to do this type of research. And yet when we look at the research being conducted at the ELA, the scientific data is sorely needed for a sustainable energy strategy.
One ELA study assesses the effects of hydroelectric development. Hydroelectric dams are often touted as a ‘clean’ energy solution. However, the ELA study raises questions about whether hydroelectric dams have similar impacts as burning fossil fuels.
“There’s a new idea around that reservoirs may be significant sources of greenhouse gases to the atmosphere. And we want to test that idea, ”says Drew Bodaly, Research Scientist at the Department of Fisheries and Oceans in this Experimental Lakes video (see below). Continue reading
EPA Survey Finds More Than Half of the Nation’s River and Stream Miles in Poor Condition
News Releases from Headquarters
Release Date: 03/26/2013
Contact Information: Stacy Kika (News Media Only), Kika.firstname.lastname@example.org, 202-564-0906, 202-564-4355
WASHINGTON — Today, the U.S. Environmental Protection Agency released the results of the first comprehensive survey looking at the health of thousands of stream and river miles across the country, finding that more than half – 55 percent – are in poor condition for aquatic life.
“The health of our Nation’s rivers, lakes, bays and coastal waters depends on the vast network of streams where they begin, and this new science shows that America’s streams and rivers are under significant pressure,” said Office of Water Acting Assistant Administrator Nancy Stoner. “We must continue to invest in protecting and restoring our nation’s streams and rivers as they are vital sources of our drinking water, provide many recreational opportunities, and play a critical role in the economy.” Continue reading
Our Source Water is Under Threat! – by Linda Heron, Chair, ORA
Presentation made by Linda Heron, Chair, ORA, at 26 November 2011 ORA Meeting.
Mercury Pollution in the Great Lakes Region: Nearly Forgotten, but Not Gone
ScienceDaily (Oct. 12, 2011) — The scope and intensity of mercury pollution in the Great Lakes region is much greater than previously reported, but additional mercury controls should bring needed improvement, according to a new summary of scientific research on the subject.
Despite general declines in mercury levels in the Great Lakes region over the past four decades, mercury concentrations still exceed human and ecological risk thresholds, especially in inland lakes and rivers, according to the report Great Lakes Mercury Connections: The Extent and Effects of Mercury Pollution in the Great Lakes Region, published in Springer’s journal Ecotoxicology. Also, new research indicates that for some species of fish and wildlife in particular areas, mercury concentrations may again be on the rise. Continue reading
Bioaccumulation of Mercury by Aquatic Biota in Hydroelectric Reservoirs: A Review and Consideration of Mechanisms, by PM Stokes and CD Wren, Institute of Environmental Studies, U of T
Methylation is accepted to be a major process controlling the biological availability of mercury, and a number of recent articles and reviews have addressed this process. Recently, the occurrence of elevated mercury in fish tissues from systems in regions considered to be remote from point or local sources of mercury have been documented.
These appear to be related to acidification of surface waters and to recent impoundments, usually in connection with hydroelectric dam construction. The present chapter addresses this second phenomenon, which is being investigated for Canadian Reservoirs by Environmental and Social Systems Analysts (ESSA) Ltd, LGL Associated and the University of Toronto in an ongoing study funded by the Canadian Electrical Association.
Elevated mercury levels have been detected in fish from a number of Canadian reservoirs. A preliminary study in 1976 of approximately 6000 fish throughout Labrador revealed that the highest mercury levels were found in fish from the Smallwood Reservoir and waters of the Churchill River downstream of the Control Structure. The maximum mercury levels in burbot (1.93 Jlwgm) and in lake trout (3.9 Jlwgm) were in fish from the reservoir.” Continue reading