Proponents of Site C always label it a “clean energy project.”
BC Hydro says “It will be a source of clean and renewable electricity for more than 100 years.”
Those claims may be deceptive.
A paper published by the Massachusetts Institute of Technology expresses concern about these intrusions on nature:
There are three primary reasons for the removal of dams. The first of these is environmental. Damming a river can substantially damage the surrounding ecosystem by changing the physical, chemical, and biological state of the river. This occurs when the flow of the river is reduced or altered, which hinders the flow of nutrients, sediments, and wildlife migration. Dams can also alter the temperature and oxygen levels of the water, which leads to poor water quality. This low quality of the water puts the surrounding environment at risk. Hydropower dams and their negative environmental effects can decimate fish populations (Maclin & Sicchio, 1999, 9).
Another reason for the demolition of dams is safety. With age and without proper maintenance and repairs, dams can become a significant threat to the surrounding communities. Certain dam failures even cost lives. For instance, four dam failures in the 1970s; the Buffalo Creek Dam in West Virginia, Canyon Lake Dam in South Dakota, Teton Dam in Idaho, and Kelly Barnes Dam in Georgia, resulted in the loss of 300 lives and hundreds of millions of dollars in damage (Maclin & Sicchio, 1999, 15).
The average life expectancy of a dam is 50 years, and 25% of the dams in the Army Corps of Engineers National Inventory of Dams are now more than 50 years old. This number is projected to increase to 85% by the year 2020. The decision of whether or not to remove a dam is made based on the ability to remedy the deficiencies that could cause failure (Maclin & Sicchio, 1999, 16).
Economic issues can also drive dam removal. As a dam ages, it can become less cost effective, especially as sediments build up and block the flow of water through the dam itself. In hydropower dams sediment can block the water from reaching the turbines which decreases efficiency even further.
Additionally, older dams require more frequent maintenance and incur higher costs to repair and operate. Eventually, it may be determined that it is not cost effective to continue to maintain and repair an obsolete dam. In certain cases, the actual removal of the dam costs less than making repairs. Dam demolition also eliminates the need for recurring maintenance funding, which saves money also. In certain circumstances, it may benefit the community economically to remove a dam (Maclin & Sicchio, 1999, 16).
Reservoirs are a major source of global greenhouse gases, scientists say, Washington Post, September 28, 2016:
There might be more greenhouse gases going into the atmosphere than we thought. That would mean an even larger need to cut.
The new paper, slated to be published next week in BioScience, confirms a significant volume of greenhouse gas emissions coming from a little-considered place: Man-made reservoirs…
Moreover, the emissions are largely in the form of methane, a greenhouse gas with a relatively short life in the atmosphere but a very strong short-term warming effect….
The new research concludes that methane accounted for 79 percent of carbon dioxide equivalent emissions from reservoirs, while the other two greenhouse gases, carbon dioxide and nitrous oxide, accounted for 17 percent and 4 percent...
Categories: Site C