Small dam construction to reduce greenhouse emissions is causing ecosystem disruption

Jun 18, 2013
This tributary of the Nu River in China is seen with its normal water flow. Credit: Kelly Kibler, courtesy of Oregon State University

Researchers conclude in a new report that a global push for small hydropower projects, supported by various nations and also the Kyoto Protocol to reduce greenhouse gas emissions, may cause unanticipated and potentially significant losses of habitat and biodiversity.

An underlying assumption that small pose fewer ecological concerns than is not universally valid, scientists said in the report. A five-year study, one of the first of its type, concluded that for certain environmental impacts the cumulative damage caused by small dams is worse than their larger counterparts.

The findings were reported by scientists from Oregon State University in the journal Water Resources Research, in work supported by the National Science Foundation.

The conclusions were based on studies of the Nu River system in China but are relevant to national in many nations or regions – India, Turkey, Latin America - that seek to expand hydroelectric power generation. Hydropower is generally favored over coal in many developing areas because it uses a and does not contribute to global warming. Also, the social and environmental problems caused by large dam projects have resulted in a recent trend toward increased construction of small dams.

"The , under Clean Development Mechanism, is funding the construction of some of these small hydroelectric projects, with the goal of creating renewable energy that's not based on fossil fuels," said Desiree Tullos, an associate professor in the OSU Department of Biological and .

"The energy may be renewable, but this research raises serious questions about whether or not the overall process is sustainable," Tullos said.

"There is damage to streams, fisheries, wildlife, threatened species and communities," she said. "Furthermore, the projects are often located in areas where poverty and illiteracy are high. The benefit to these local people is not always clear, as some of the small hydropower stations are connected to the national grid, indicating that the electricity is being sent outside of the local region.

This tributary of the Nu River in China has lost its water flow below a dam. Credit: Kelly Kibler, courtesy of Oregon State University

"The result can be profound and unrecognized impacts."

This study was one of the first of its type to look at the complete range of impacts caused by multiple, small hydroelectric projects, both in a biophysical, ecological and geopolitical basis, and compare them to large . It focused on the remote Nu River in China's Yunnan Province, where many small dams producing 50 megawatts of power or less are built on tributaries that fall rapidly out of steep mountains. There are already 750,000 dams in China and about one new dam is being built every day, researchers say.

Among the findings of the report as it relates to this region of China:

  • The cumulative amount of energy produced by small hydroelectric projects can be significant, but so can the ecological concerns they raise in this area known to be a "hotspot" of biological diversity.
  • Per megawatt of energy produced, small tributary dams in some cases can have negative environmental impacts that are many times greater than large, main stem dams.
  • Many dams in China are built as part of a state-mandated policy to "Send Western Energy East" toward the larger population and manufacturing centers.
  • Small dams can have significant impacts on habitat loss when a river's entire flow is diverted into channels or pipes, leaving large sections of a river with no water at all.
  • Fish, wildlife, water quality and riparian zones are all affected by water diversion, and changes in nearby land use and habitat fragmentation can lead to further species loss.
  • The cumulative effect on habitat diversity can be 100 times larger for small dams than large dams.
  • Policies encouraging more construction of small dams are often developed at the national or international level, but construction and management of the projects happen at the local level.
  • As a result, mitigation actions and governance structures that would limit social and environmental impacts of small hydropower stations are not adequately implemented.

"One of the things we found generally with small dams is that there was much less oversight and governance with the construction, operation and monitoring of small hydropower," Tullos said. "On the large, main stem dams, people pay attention to what's going on. On a small hydropower project, no one notices if minimum flows are being maintained. Or if a pump breaks, the hydropower station might sit idle for long periods of time."

Researchers said the key finding of the research, contrary to prevailing but unvalidated belief, is that "biophysical impacts of small hydropower may exceed those of large hydropower, particular with regard to habitat and hydrologic change."

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More information: onlinelibrary.wiley.com/doi/10… /wrcr.20243/abstract

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User comments : 22

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gwrede
1.8 / 5 (15) Jun 18, 2013
I think we should start protecting nature and the planet from environmentalists.
antigoracle
1.5 / 5 (15) Jun 18, 2013
And so the stupidity escalates to actually destroying the planet for the sake of the AGW lie.
Neinsense99
3.2 / 5 (13) Jun 18, 2013
And so the stupidity escalates to actually destroying the planet for the sake of the AGW lie.

And so the unproductive commentaries continue in the effort to manufacture a lie.
Howhot
4.1 / 5 (9) Jun 19, 2013
I think we should start protecting nature and the planet from environmentalists.

But environmentalists are trying to protect nature from the likes of you. So isn't that just circular reasoning?
antigoracle
1.3 / 5 (13) Jun 19, 2013
And so the stupidity escalates to actually destroying the planet for the sake of the AGW lie.

And so the unproductive commentaries continue in the effort to manufacture a lie.

As I said, the stupidity escalates.
deepsand
3.1 / 5 (15) Jun 19, 2013
And so the stupidity escalates to actually destroying the planet for the sake of the AGW lie.

And so the unproductive commentaries continue in the effort to manufacture a lie.

As I said, the stupidity escalates.

That is easily remedied by your ceasing to post.
Sinister1811
3.7 / 5 (12) Jun 19, 2013
I think we should start protecting nature and the planet from environmentalists.


Again with a complete absence of logic. I'm thinking the likes of gwrede and antigorical are trolling. Because, seriously, how can someone be that irrational?
gwrede
1.3 / 5 (13) Jun 19, 2013
I think we should start protecting nature and the planet from environmentalists.
Again with a complete absence of logic. I'm thinking the likes of gwrede and antigorical are trolling. Because, seriously, how can someone be that irrational?
Heh, well, not entirely trolling. I have always had a hard time accepting coal as a substitute for nuclear, especially with all the AGW talk at the same time. And a few other things. Seems like green people don't have the one brain cell that gives rational and logical thinking. Yes, they are well meaning, but that's not enough.

I snicker at the thought of Bill Maher or the late Christoffer Hitchens giving environmentalists a little feedback on TV. Sadly, I'll never see the day.

antigoracle
1.6 / 5 (14) Jun 19, 2013
I think we should start protecting nature and the planet from environmentalists.


Again with a complete absence of logic. I'm thinking the likes of gwrede and antigorical are trolling. Because, seriously, how can someone be that irrational?

Listen to Environmentalist Douglas Adams take on the movement.
Jump to 1:17:40 - http://www.youtub...8HBuDjgc
Howhot
4 / 5 (9) Jun 20, 2013
The amazing @anti (whose arm pits have developed their own ecosystem) suggest we listen to a boring 2hr talk from Douglas Adams. And anti your point was ..... same as always. BS.

You know the only people that are ignorant are the deniers like you. That is the bottom line @anti. You know everything we say is truth, backed by science, That is unlike your Wattsup troll site, or the half dozen IRS 501c troller bait sites that you like to visit.
.

antigoracle
1.3 / 5 (13) Jun 20, 2013
The amazing @anti (whose arm pits have developed their own ecosystem) suggest we listen to a boring 2hr talk from Douglas Adams. And anti your point was ..... same as always. BS.

You know the only people that are ignorant are the deniers like you. That is the bottom line @anti. You know everything we say is truth, backed by science, That is unlike your Wattsup troll site, or the half dozen IRS 501c troller bait sites that you like to visit.
.


They say "ignorance is bliss" and that would explain your condition and why you would choose to stay in it. How dumb must you be not to comprehend when I said - Jump to 1:17:40 - in the video.
deepsand
3.3 / 5 (14) Jun 21, 2013
The amazing @anti (whose arm pits have developed their own ecosystem) suggest we listen to a boring 2hr talk from Douglas Adams. And anti your point was ..... same as always. BS.

You know the only people that are ignorant are the deniers like you. That is the bottom line @anti. You know everything we say is truth, backed by science, That is unlike your Wattsup troll site, or the half dozen IRS 501c troller bait sites that you like to visit.

They say "ignorance is bliss" and that would explain your condition and why you would choose to stay in it. How dumb must you be not to comprehend when I said - Jump to 1:17:40 - in the video.

You lack the humour to be entertaining, the knowledge to be informative, and have all the charm and attraction of a deceased rat which suffered from leprosy and incontinence.
AT210
1.7 / 5 (11) Jun 22, 2013
You know the only people that are ignorant are the deniers like you. That is the bottom line @anti. You know everything we say is truth, backed by science, That is unlike your Wattsup troll site, or the half dozen IRS 501c troller bait sites that you like to visit.
.


Care to look at these for a few moments then?

http://dailycalle...y-wrong/

http://www.econom...e-change

http://www.dailym...-it.html

Your ignorant comment is extremely ignorant too I must say. We so happen to be meteorologists, physicists, oceanographers standing right here demanding for a second look into this AGW issue before dangerous taxes are imposed to unknowing, ignorant people like you paying money for nothing. I'm curious, what's your profession?
deepsand
3.2 / 5 (13) Jun 23, 2013
You know the only people that are ignorant are the deniers like you. That is the bottom line @anti. You know everything we say is truth, backed by science, That is unlike your Wattsup troll site, or the half dozen IRS 501c troller bait sites that you like to visit.

Care to look at these for a few moments then?

http://dailycalle...y-wrong/

Your ignorant comment is extremely ignorant too I must say. We so happen to be meteorologists, physicists, oceanographers standing right here demanding for a second look into this AGW issue before dangerous taxes are imposed to unknowing, ignorant people like you paying money for nothing. I'm curious, what's your profession?

Well, you certainly didn't help your cause with those citations. :rolleyes:
antigoracle
1.3 / 5 (13) Jun 23, 2013
The amazing @anti (whose arm pits have developed their own ecosystem) suggest we listen to a boring 2hr talk from Douglas Adams. And anti your point was ..... same as always. BS.

You know the only people that are ignorant are the deniers like you. That is the bottom line @anti. You know everything we say is truth, backed by science, That is unlike your Wattsup troll site, or the half dozen IRS 501c troller bait sites that you like to visit.

They say "ignorance is bliss" and that would explain your condition and why you would choose to stay in it. How dumb must you be not to comprehend when I said - Jump to 1:17:40 - in the video.

You lack the humour to be entertaining, the knowledge to be informative, and have all the charm and attraction of a deceased rat which suffered from leprosy and incontinence.

Obviously ignorance has reached epidemic proportions amongst the AGW Alarmist turds.
deepsand
3.2 / 5 (13) Jun 23, 2013
AO is like an insane woodpecker looking for a grub in a block of concrete.
gwrede
1 / 5 (12) Jun 23, 2013
I snicker at the thought of Bill Maher or the late Christoffer Hitchens giving environmentalists a little feedback on TV. Sadly, I'll never see the day.
Don't get me wrong, I want to save rare species, the rain forests, and in general I think we should avoid leaving footprints, because that really is the only way to have a nature left for our grandchildren.

But I don't like those environmentalists who basically have environmentalism as a religion. (And that, sadly, is almost all of them.) Those people rave about random things we should do, and do right now, without thinking and reasoning, and the hordes stampede across the landscape looking for the odd flower to Protect, while entire meadows turn into what the fields looked like after Woodstock.

And reasoning with these people is as hard as with any fundamentalists, be it religion or politics. (This last sentence will guarantee me Ones from all of them.)
Howhot
4.5 / 5 (8) Jun 24, 2013
@gwrede say;
But I don't like those environmentalists who basically have environmentalism as a religion.


So basically I guess you don't like me or the majority of sane people in the world! "And reasoning with these people" is hard.

OMG! Dim bulb alert! Dim bulb alert! We have a Dim bulb. All hands on deck, this soul is need of fundamental environmental transmogrification! @gwrede, you might want to start at this site;

http://www.skepti...nce.com/

deepsand
3.3 / 5 (14) Jun 24, 2013
But I don't like those environmentalists who basically have environmentalism as a religion. (And that, sadly, is almost all of them.) Those people rave about random things we should do, and do right now, without thinking and reasoning, and the hordes stampede across the landscape looking for the odd flower to Protect, while entire meadows turn into what the fields looked like after Woodstock.

And reasoning with these people is as hard as with any fundamentalists, be it religion or politics. (This last sentence will guarantee me Ones from all of them.

What will draw the 1s is your having conflated into a single group all environmentalists who feel strongly about the necessity of preserving Nature's delicate balance, and then described them as being categorically uniformed or ill informed and irrational.
antigoracle
1.3 / 5 (12) Jun 26, 2013
So basically I guess you don't like me or the majority of sane people in the world! "And reasoning with these people" is hard.

Reasoning with sane people is not hard, but stupid ones like you, on the other hand, is impossible.
Howhot
5 / 5 (6) Jun 27, 2013
Oooo the little wart-ed one whose odoriferous presents in a room inspires a depressed mood, spoke; "Reasoning with sane people is not hard, but stupid ones like you, on the other hand, is impossible"

You must be a dodgeball expert. The kind that will never ever carry the ball sacks of your team mates. Ohh when the mighty wart faced one; anti says "sane people" does one know who he is talking about? I think not. Only a very dim-bulb says "but stupid". You need some environmental transmogrification! dodgeball anti!

deepsand
3 / 5 (10) Jun 28, 2013
So basically I guess you don't like me or the majority of sane people in the world! "And reasoning with these people" is hard.

Reasoning with sane people is not hard, but stupid ones like you, on the other hand, is impossible.

AO's problem is that he fails to recognize his own stupidity as being the reason why he has difficulty engaging in civil and rational discourse with informed intelligent people.