Quantcast

Dams Cause Climate Change, They Are Not Clean Energy

Insights + Opinion
Glen Canyon Dam in Arizona.

People believe hydroelectric dams provide clean energy. It's not true.


I don't blame the public or the media for making this false claim—I've heard it come out of the mouth of the biggest dam operator in the Southwest U.S. (see CRWUA presentation, Dec. 2013, slide 13), and the media often repeats it (see E&E article June 30). Unfortunately, it was further repeated in a horribly misguided “study" put out by the U.S. Dept of Energy in April.

Glen Canyon Dam in Arizona.

But when I heard it quoted three months ago in this May 12 New Yorker story out of the mouth of Mark Tercek who is CEO of The Nature Conservancy to rationalize his organization's support of new dams in Columbia, I knew it's time to once-again address this disastrous myth.

Tercek is quoted as saying: “Environmentalists generally hate dams, even though they're clean energy."

Dams are not “clean energy." Dams are, in fact, causing climate change. A growing body of science is studying just how bad dams are. Here are the issues:

  • Organic material—vegetation, sediment and soil—flows from rivers into reservoirs and decomposes emitting methane and carbon dioxide into the water and then the air throughout the hydro-electric generation cycle. Studies indicate that where organic material is the highest (in the tropics or in high sediment areas) hydro-electric dams can actually emit more greenhouse gases than coal-fired powerplants. (See this report from International Rivers, this peer-reviewed article reported in Science Daily, this news report on Nature World News and this report about the Belo Monte dam). These methane emissions are not limited to tropical areas; they occur in the U.S. too. “Methane springs" are widely reported on the mud flats of Lake Powell which is a reservoir behind Glen Canyon Dam on the Colorado River (Living Rivers, slide 41), and “trains" of “methane bubbles" have been reported floating on Lake Powell (High Country News, page 5, May 17, 2011). As far back as 1948, the U.S. Geological Survey examined what they then called “gas pits" in the mud flats of Lake Mead which is a reservoir behind Hoover Dam on the Colorado River (USGS, page 162 and 180). As a real conversation ender, Brazil's National Institute of Space Research estimates that “dams are the largest single [human-caused] source of methane, being responsible for 23 percent of all methane emissions due to human activities."
  • Large dams contain enormous amounts of cement which during the construction process uses massive amounts of energy that emits greenhouse gas emissions. For one medium-sized dam project proposed for the Cache la Poudre River in Colorado, it is estimated that the construction would emit 218,000 metric tons CO2-equivalents which equals the emissions from almost 46,000 automobiles on the road for one year. Larger dams, such as Hoover Dam which contains 4.36 million cubic yards of concrete, would have exponentially higher climate change impacts from construction. The largest hydro-electric dam on the planet—the Three Gorges Dam in China—contains 27.15 million cubic meters of cement.
  • Dams that divert water out of rivers may have significant additional climate change impacts because they drain and dry up downstream wetlands that are “carbon sinks" holding vast amounts of greenhouse gases in soils. This draining and dry-up causes carbon and methane to be released and emitted into the air. A proposal for a dam on the Cache la Poudre River in Colorado would dry up 1,700 acres of wetlands thus emitting about 7,000 metric tons of CO2 equivalents. As just one more example, when the Colorado River was diverted and drained, the dams and diversions dried up about 2 million acres of wetlands in the former Colorado River Delta—the climate change impact of destroying those wetlands was likely staggering.
  • Some dams, like the proposed massive ecosystem-wide Belo Monte dams on the Amazon River in Brazil, also include massive deforestation plans on areas that will be flooded by behind the reservoirs. The deforestation itself would release enormous amounts of greenhouse gas emissions.

Read page 1

“Methane springs" are widely reported on the mud flats of Lake Powell which is a reservoir behind Glen Canyon Dam on the Colorado River and “trains" of “methane bubbles" have been reported floating on Lake Powell.

Just how much of climate change is caused by dams and reservoirs is not completely known—we need more research before we build any more dams and potentially make a terrible mistake based on myths, propaganda and false information.

Some hydro-electric dams and reservoirs are not as bad as others—some may be worse climate change emitters than coal power plants, most are likely better (see report from International Rivers). But, most hydro-electric dams are likely much worse climate change emitters than wind or solar power, so saying that hydro-electric is better than coal power is just a straw-man argument unsupported by the science and economics of 21st century renewable energy. Increasingly, wind and solar is cheaper, faster and cleaner.

Deforestation at the Belo Monte Dam in the Amazon.

Further, many dams and reservoirs are not hydro-electric plants at all and are only used for water storage and diversion, in which case they absolutely increase climate change emissions when they're built and every single day they continue to exist.

Dams are not clean energy and everyone involved with dams and energy—hydro-plant operators, media, government officials and environmentalists—must stop saying it.

Dams cause climate change. Period.

YOU ALSO MIGHT LIKE

DamNation Explores History of Dams and Brilliance of Rivers Reborn

Women Without Borders, Patagonia Without Dams

10 Things You Should Know About Dams

EcoWatch Daily Newsletter

MStudioImages / E+ / Getty Images

By Jillian Kubala, MS, RD

Backpacking is an exciting way to explore the wilderness or travel to foreign countries on a budget.

Read More Show Less
Tim P. Whitby / 21st Century Fox / Getty Images

The beauty products we put on our skin can have important consequences for our health. Just this March, the U.S. Food and Drug Administration (FDA) warned that some Claire's cosmetics had tested positive for asbestos. But the FDA could only issue a warning, not a recall, because current law does not empower the agency to do so.

Michelle Pfeiffer wants to change that.

The actress and Environmental Working Group (EWG) board member was spotted on Capitol Hill Thursday lobbying lawmakers on behalf of a bill that would increase oversight of the cosmetics industry, The Washington Post reported.

Read More Show Less
Sponsored
A protest march against the Line 3 pipeline in St. Paul, Minnesota on May 18, 2018. Fibonacci Blue / CC BY 2.0

By Collin Rees

We know that people power can stop dangerous fossil fuel projects like the proposed Line 3 tar sands oil pipeline in Minnesota, because we've proved it over and over again — and recently we've had two more big wins.

Read More Show Less
Scientists released a study showing that a million species are at risk for extinction, but it was largely ignored by the corporate news media. Danny Perez Photography / Flickr / CC

By Julia Conley

Scientists at the United Nations' intergovernmental body focusing on biodiversity sounded alarms earlier this month with its report on the looming potential extinction of one million species — but few heard their calls, according to a German newspaper report.

Read More Show Less
DoneGood

By Cullen Schwarz

Ethical shopping is a somewhat new phenomenon. We're far more familiar with the "tried and tested" methods of doing good, like donating our money or time.

Read More Show Less
Sponsored
Pixabay

Summer is fast approaching, which means it's time to stock up on sunscreen to ward off the harmful effects of sun exposure. Not all sunscreens are created equally, however.

Read More Show Less
Mark Wallheiser / Getty Images

The climate crisis is a major concern for American voters with nearly 40 percent reporting the issue will help determine how they cast their ballots in the upcoming 2020 presidential election, according to a report compiled by the Yale Program on Climate Change Communication.

Of more than 1,000 registered voters surveyed on global warming, climate and energy policies, as well as personal and collective action, 38 percent said that a candidate's position on climate change is "very important" when it comes to determining who will win their vote. Overall, democratic candidates are under more pressure to provide green solutions as part of their campaign promises with 64 percent of Democrat voters saying they prioritize the issue compared with just 34 percent of Independents and 12 percent of Republicans.

Read More Show Less
Flooding in Winfield, Missouri this month. Jonathan Rehg / Getty Images

President Donald Trump has agreed to sign a $19.1 billion disaster relief bill that will help Americans still recovering from the flooding, hurricanes and wildfires that have devastated parts of the country in the past two years. Senate Republicans said they struck a deal with the president to approve the measure, despite the fact that it did not include the funding he wanted for the U.S.-Mexican border, CNN reported.

"The U.S. Senate has just approved a 19 Billion Dollar Disaster Relief Bill, with my total approval. Great!" the president tweeted Thursday.

Read More Show Less