No. Large hydro dams destroy rivers and ecosystems, and their reservoirs release significant levels of methane. Reservoirs also produce and concentrate high levels of methylmercury—you may have seen signs on their banks warning you not to eat the fish or to limit their consumption. Modern alternative technologies are not only cleaner and greener than dams, they are also much cheaper, and cheaper electricity helps encourage the switch from fossil fuels to electricity.

The Long Answer:

Hydroelectricity is neither green nor “clean” (clean is a lower bar than green). A growing number of jurisdictions no longer class hydroelectricity as green and consequently won’t pay as much to import it. Why?

• It’s now known that reservoirs are major emitters of methane and CO2, which are byproducts of the decomposition of plant and other life submerged under reservoirs.
  – Hydroelectric dams emit a billion tonnes of greenhouse gases a year, study finds
  – The hydropower paradox: is this energy as clean as it seems?
• Hydro dam reservoirs also create high concentrations of methylmercury, which poisons fish and water. Most BC reservoirs features posted signs warning visitors not to eat the fish they catch or to limit their consumption of it. As with methane, methylmercury is a byproduct of the anaerobic decomposition of drowned plant and other life. This damage is long-lasting, too: when dams are later decommissioned, the mercury-filled soils they leave behind must be treated as toxic waste, so converting valleys back to agricultural land or natural habitat is not that simple.
• Dams also desiccate downstream areas and deltas, leading to death of ecosystems and further release of CO2 and methane. In the case of the Site C dam, the threat is to the Peace Athabasca Delta, already impacted by two prior dams on the Peace River (WAC Bennett and Peace Canyon).
• The concrete in mega-dams has a massive carbon footprint. Site C will require millions of cubic metres of concrete to be poured.