The New England Clean Energy Connect (NECEC), a proposed $1.2 billion joint transmission project between Hydro-Québec and Avangrid has been advertised by its developers as a way to bring clean and responsible energy to the U.S. under a 20-year deal.

The 1,200 MW transmission line would funnel hydropower power from Canada to the U.S. Northeast. But scientific evidence has shown that emissions from hydroelectric dams are greater than emissions from wind power, natural gas and in some cases, coal facilities.

Politicians too often make “vacuous statements about a particular energy source being clean, but that is not the case,” Gary Wockner, executive director and co-founder of Save The World’s Rivers, told NetZero Insider. Hydroelectric power plants can be as bad as natural gas, according to a 2016 study published in Bioscience. Another study published in Environmental Science and Technology found that in some cases, hydroelectric power plants are worse for the climate than coal. [Editor’s Note: An earlier version of this story incorrectly stated that the Bioscience study had compared hydropower emissions to coal.]

Massachusetts Gov. Charlie Baker has thrown his support behind NECEC as a means of reaching the state’s GHG emission reduction targets, and the Maine Public Utilities Commission, Maine Department of Environmental Protection and U.S. Army Corps of Engineers all signed off on the project as reducing carbon emissions in the Northeast.

However, the analysis conducted by the state and federal agencies does not include the methane emissions created by the source of the energy: the hydroelectric dams in Québec, which flooded 308 million acres of boreal forests to create reservoirs. The methane emissions are not produced in the U.S., but that does not mean the source of the energy will be clean, Wockner said.

“If you are trying to replace natural gas with hydropower, you are not getting cleaner energy,” he said. If the state and federal agencies “follow the science, they will see they are making a huge mistake.”

Hydro Emissions

Initial studies that exposed the GHG emissions from hydroelectric dams were done more than 35 years ago in the tropics of Brazil, where the methane released was double that of coal plants, which produced the same amount of electricity.

Since then, more than 37 studies have been published on dams in the U.S. and Canada and their production of GHG emissions. Lifecycle emissions of some large-scale hydropower facilities can be more than 0.5 pounds of carbon dioxide per KW-hour. Natural gas burning has life cycle emissions averaging between 0.6 and 2 pounds of carbon dioxide per KW-hour.

In 2016, researchers found that rotting vegetation in reservoir water created by hydroelectric dams emit about a billion tons of GHG every year, or 1.3% of the total annual human-caused emissions. Over a 100-year timescale, dams produce more methane than biomass burning and rice plantations.

The vegetation in the boreal forests of Québec that is flooded for hydroelectric dam reservoirs goes through the process of anaerobic decomposition. Vegetation decomposes over time, changing the soil and bubbling up methane in a way that an existing, non-human-made lake does not because they have existed for thousands of years and are not breaking down forest vegetation.

Lake Mead, a reservoir formed by the Hoover Dam on the Colorado River, emits the same amount of GHGs as coal-fired power plants that produce the same amount of electricity, according to a study published in 2016 by a team of Swiss scientists.

Lynn St. Laurent, spokesperson for Hydro-Québec, said that the cooler temperatures in northern Canada mean less methane is emitted in the company’s reservoirs.  

But the Churchill Falls underground generating station in Labrador, Canada, one of the largest hydroelectric projects in the world, emits the same amount of GHGs as a natural gas plant, according to the Swiss study.

The majority of consumers in both Massachusetts and New York City already rely on natural gas to heat their homes and water. Purchasing hydroelectric power from a Canadian government-owned company “is just dirty politics,” Wockner said. “The hydropower industry is very powerful.”

The industry has carried out a massive advertising campaign in Massachusetts, Maine and New York, claiming its projects will bring clean energy and jobs to the region.

“There is a lot of politics, power and money trying to squelch the science,” Wockner said, and it has been a “big challenge for scientists to get the science out.”

New York is considering another $2.2-billion transmission corridor from Hydro-Québec plants through Lake Champlain and the Hudson River to bring power to New York City. But the city is required to report imported emissions, and officials will realize the mistake they’ve make, Wockner said.

Hydro and First Nations 

In addition to methane, reservoirs release methylmercury in the soil, poisoning the water and wildlife.

The methylmercury poisoning directly affects First Nations, which rely on regional natural food sources. Hydroelectric dams have disrupted and disturbed millennia-old migratory patterns of fish and other wildlife that make up food webs for the First Nations.

In June 2019, the United Nations Special Rapporteur on human rights and hazardous substances and wastes, Baskut Tuncak, called on the Canadian federal government to use its leverage to address concerns about lack of proper consultation with Indigenous people as well as the expected methylmercury poisoning.  

Michel Plante, head of health and safety for Hydro-Québec, said in a statement that levels of methylmercury return to normal 20 to 30 years after the creation of a reservoir, and fish from natural rivers have some mercury regardless of hydropower development.

More than 36% of the electricity that NECEC would export to Massachusetts would come from hydroelectric dams built on First Nation territory without their consent, according to the Anishnabe First Nation of Lac Simon, the Abitibiwinni First Nation, the Anicinape Community of Kitcisakik, the Innu Nation of Pessamit and the Atikamekw Nation of Wemotaci.

Lucien Wabanonik, elected councilor of the Nation Anishnabe of Lac Simon in Québec, wrote in an opinion column submitted to Bangor Daily News that the dams and associated infrastructure have “robbed us, not only of our resources, but also of our culture and our way of life, which is no longer sustainable.”

In total, 33 production structures, 130 dams and dikes, 10,400 km2 of reservoirs, tens of thousands of kilometers of transmission, distribution and road lines have been illegally installed on First Nation land, according to a statement from the Innu First Nation of Pessamit. These facilities continue to be operated by Hydro-Québec in violation of the rights recognized by the Constitution Act of 1982 and the jurisprudence of the Supreme Court of Canada, according to the Tribe.

“These successive and massive hydroelectric developments on our traditional territories have never translated into a better quality of life for the members of the communities most directly and negatively impacted,” the statement said.