Pak Mun Dam: Death Of A River

[webfact]

Death of a river

By Chularat Saengpassa

20 years since the construction of the Pak Mun Dam, communities are still fighting the devastating effects

Now that Thailand has a new government, Sompong Wiangjan will be returning to Bangkok once again, determined to liberate her beloved Mun River from the big dam that she and thousands of other families believe have destroyed the environment in Ubon Ratchathani. "I have been campaigning for this for two decades already. I will never give up," says the 62-year-old.

She has rallied in front of Government House in Bangkok more times that she can remember and watched several governments come and go. She says that politicians in power have listened but have never really acted on the peoples' requests.

In March this year, her group and its allies pressed the Abhisit Vejjajiva government to open the sluices of the Pak Mun Dam year-round for five consecutive years to see if the ecological abundance would return.

From the moment the Tana Islet was dynamited to pave the way for the dam construction in 1991, the fish started to disappear from the river.

As the livelihoods of the locals faltered, activists stepped forward to demand that the government provide help.

"Several studies have been conducted over time. It should be clear that the dam has hurt locals and their environment. I think the government should start opening the sluice gates all year round and stop trying to buy time," Sompong says.

In response to the group's petition in March, the Abhisit administration suggested that a study be conducted to assess the impacts if the sluice gates were indeed to be opened throughout the year.

"It's been a very long fight. Many people who have fought alongside me have already passed away," Sompong says, her weariness evident.

Among her late colleagues is Wanida Tantiwittayapitak, a woman for whom she had great respect and admiration.

"We plan to organise a big merit-making ceremony for the late heroes and heroines later this year," she says.

According to her, the Pak Mun Dam was illegally built because its implementing agencies failed to conduct a feasibility study and an environmental-impact assessment before construction started. Moreover, the Electricity generating Authority of Thailand has yet to provide sufficient compensation to those whose land was expropriated to make way for the dam.

To press for compensation both for expropriation of their land and the dam gate opening, villagers have built communities on dam property. Today, these communities are home to about 6,000 households. Occasional clashes have broken out with the authorities and several criminal complaints, including treason, have been filed against a number of them.

Sompong herself has been charged with treason and criminal conspiracy for taking part in rallies against the dam.

"Why should the authorities treat us as criminals? All we have done is fight to restore our rights to live on our own land and make a living the way we have always done or, at the very least, for the compensation promised after the dam was built," she complains. "If defending one's rights and calling for rightful compensation are crimes, then I don't know how Thai society can continue."

On a bright note, three of the charges against Sompong have already gone past their statute of limitation. However, the charge of criminal conspiracy remains valid for the next few years, she says. Arrest warrants have been issued for Sompong and other 13 activists but local police have so far seemed reluctant to apprehend her.

"The police belong here. They know the facts," she says.

Sompong has dedicated her crusade to the late activist Wanida, who co-founded the Assembly of the Poor and inspired the movement against Pak Mun Dam, saying that the charges should be dropped against Wanida posthumously, as a mark of honour.

She points out that Wanida helped give the disadvantaged a voice and that more than 900,000 people, including members of the Assembly of the Poor, grouped together to campaign for their rights affected by government projects.

And while she waits to discover the new government's stance over her group's demands and the criminal charges against activists and villagers, she'll continue to call attention to the plight of her river, as well as giving lectures and speeches.

The Pak Mun Dam: A timeline

- April 1, 1991: The Electricity Generating Authority of Thailand (EGAT) begins construction of the Pak Mun Dam

- December 10, 1991: The World Bank approves the loan, which increases from Bt3.8 billion to Bt6.6 billion, on the grounds that it's a small project with small impact.

- March 3, 1993: Some 300 people raid the construction site and seize explosives and construction tools before proposing a six-point demand that includes allocation of farmland and compensation at market prices.

- March 6, 1993: Pro-dam demonstrators clash with anti-dam protesters leaving 33 injured.

- March 14, 1993: EGAT public relations director Supin Panyamak says five demands are acceptable but not the sixth. This last point says that if one party is not happy with the compensation, the matter can be put to an arbitrator whose decision will be final. EGAT says it can only sign contract accepting the demands once it has government agreement.

- March 19, 1993: Demonstrators agree to disperse and send four representatives to join a new committee agreed under the contract.

- April 1994: Construction of the dam is completed and it starts generating electricity.

- October 14, 1994: 2,000 villagers protest at Ubon Ratchathani City Hall demanding that EGAT pay compensation for their loss of income.-

- March 22, 1995: EGAT agrees to pay the compensation for three years' loss of incomes to 3,955 families at Bt90,000 each.

- 1995-1996: Protesters demonstrate as incomes shrink and fish are unable to lay eggs upstream of the dam despite the fish ladder.

- March 26, 1996: Dam protesters join others affected by 47 state projects in putting pressure on the government.

- April 22, 1996: The Banharn Silapa-acha administration passes a Cabinet resolution to solve all 47 cases.

- January 25, 1997: Fed up with the lack of progress, a second movement is organised to pressure the Chavalit Yongchaiyudh administration.

- May 2, 1997: A committee assigned by the Cabinet resolution on April 29, 1997 is told to follow up the allocation of 15 rai of land or pay Bt500,000 per family to those affected by the Pak Mun dam and solve the problems of the other demonstrators.

- April 21, 1998: The Chuan Leekpai administration cancels the Chavalit administration's resolution on the grounds that they have no policy to pay retrospective compensation for a project that has already been completed.

- March 23, 1999: 5,000 people affected by the Pak Mun Dam set up the Mae Mun Man Yeun 1 Ville on the dam ridge in Ubon Ratchahani's Khong Jiam district.

- May 15, 2000: Demonstrators seize the Pak Mun Dam power-generating building's parking lot and set up the Mae Mun Man Yeun 7 Ville, pressuring EGAT opening all eight sluice gates to let the fish lay eggs upstream of the dam.

- April 17, 2001: The Thaksin Shinawatra administration passes a Cabinet resolution to open the Pak Mun Dam sluice gates for four months and close them for eight months.

- 2006-2007: Protesters ask the Surayud Chulanont government to open the Pak Mun Dam sluice gates all year round. The demands are not met.

- 2010-2011: Protesters ask the Abhisit Vejjajiva government to open the Pak Mun Dam sluice gates all year round. The demands are not met.

-- The Nation 2011-08-18

[Latindancer]

There's even a Wikipedia page about it. http://en.wikipedia....iki/Pak_Mun_Dam

Here are the essentials not already mentioned:

"It was constructed by the Electricity Generating Authority of Thailand (EGAT) with support from the World Bank at a total cost of US$240 million, and completed in 1994."

"In all around 25,000 villagers claim to have been affected by the dam. Protests have been staged at the dam site and outside Government House in Bangkok. EGAT has paid out US$44.24 million in relocation compensation, plus US$15.8 million for loss of fisheries."

(Note: I calculated how much each of the 25,000 people would have got from the US$44 million......it's US$1760........but that's for every man, woman and child. At today's rates that's 52,000 baht each.

Plus about one third of that as well........as 15 million is about one third of 44 million)

"The World Commission on Dams report also raised doubts about the amount of power which the dam can produce. It argued that the dam could not reliably produce the anticipated amount of electricity, making it economically nonviable. EGAT responded that such consistent electricity production was unnecessary, and that the dam was a useful source of electricity (although it is not clear how it is useful, since Thailand produces 130% of its daily electrical needs)."

And from another website:

"The people's protest against the dam has continued for more than 10 years, and they are still conducting mass demonstrations of 3000 people. Having been criticized by the government and urban residents for demanding money, in late 1999 the protestors changed their demand to the decommissioning of the dam. By doing so, they are trying to show that they are fighting for life; not simply monetary compensation. "

Edited August 18, 2011 by Latindancer

[OzMick]

And now for the positives:

290 GWh/yr power production (not huge, but significant)

700,000 t/yr coal (or equivalent fossil fuel) not burnt and pollutants not produced

quality of local environment increased

tourism potential increased

flood mitigation

A common problem with fish ladders, which will work when properly designed, is that the locals find them a good place to catch fish. Not that I would suggest that this would happen here, Thais being known for the altruism and forward-thinking.

[OzMick]

There's even a Wikipedia page about it. http://en.wikipedia....iki/Pak_Mun_Dam

Here are the essentials not already mentioned:

"It was constructed by the Electricity Generating Authority of Thailand (EGAT) with support from the World Bank at a total cost of US$240 million, and completed in 1994."

"In all around 25,000 villagers claim to have been affected by the dam. Protests have been staged at the dam site and outside Government House in Bangkok. EGAT has paid out US$44.24 million in relocation compensation, plus US$15.8 million for loss of fisheries."

(Note: I calculated how much each of the 25,000 people would have got from the US$44 million......it's US$1760........but that's for every man, woman and child. At today's rates that's 52,000 baht each.

Plus about one third of that as well........as 15 million is about one third of 44 million)

"The World Commission on Dams report also raised doubts about the amount of power which the dam can produce. It argued that the dam could not reliably produce the anticipated amount of electricity, making it economically nonviable. EGAT responded that such consistent electricity production was unnecessary, and that the dam was a useful source of electricity (although it is not clear how it is useful, since Thailand produces 130% of its daily electrical needs)."

And from another website:

"The people's protest against the dam has continued for more than 10 years, and they are still conducting mass demonstrations of 3000 people. Having been criticized by the government and urban residents for demanding money, in late 1999 the protestors changed their demand to the decommissioning of the dam. By doing so, they are trying to show that they are fighting for life; not simply monetary compensation. "

The World Commission on Dams Report is a greenie-orientated piece of garbage with mis-leading statements, biased opinions and lots of psuedo-science. As an example, it takes the worst possible scenario (a large, shallow dam in the tropics with a tiny hydro-station) and comes out with a statement that in some cases hydro dams produce as much CO2 as the equivalent coal-fired station, without mentioning that the CO2 comes from rotting vegetation that would otherwise be washed out to sea to rot there.

Every environmental effect is seen as a negative, such as a west coast South Island of NZ dam which has reduced the huge storm-surge flows, stabilising the river, to the detriment of a water-fowl, but to the benefit of trout. Guess which the locals prefer, besides not having the river change course occasionally, washing away homes and farms. If you havn't been there, it is hard to appreciate the huge volumes of rain and the power of the rivers - bridges have signs warning NOT to stop to take photos of the storm because a wall of water higher than the bridge may well wash you to your death.

As for the un-reliability of production, this has something to do with what is called the wet season. Yep, it's not year round, but it's pretty regular and predictable.

When a country produces more of a commodity than it consumes, this is called an export. Some people look on this as a good thing for any number of reasons.

[TerraPosse]

There's even a Wikipedia page about it. http://en.wikipedia....iki/Pak_Mun_Dam

Here are the essentials not already mentioned:

"It was constructed by the Electricity Generating Authority of Thailand (EGAT) with support from the World Bank at a total cost of US$240 million, and completed in 1994."

"In all around 25,000 villagers claim to have been affected by the dam. Protests have been staged at the dam site and outside Government House in Bangkok. EGAT has paid out US$44.24 million in relocation compensation, plus US$15.8 million for loss of fisheries."

(Note: I calculated how much each of the 25,000 people would have got from the US$44 million......it's US$1760........but that's for every man, woman and child. At today's rates that's 52,000 baht each.

Plus about one third of that as well........as 15 million is about one third of 44 million)

"The World Commission on Dams report also raised doubts about the amount of power which the dam can produce. It argued that the dam could not reliably produce the anticipated amount of electricity, making it economically nonviable. EGAT responded that such consistent electricity production was unnecessary, and that the dam was a useful source of electricity (although it is not clear how it is useful, since Thailand produces 130% of its daily electrical needs)."

And from another website:

"The people's protest against the dam has continued for more than 10 years, and they are still conducting mass demonstrations of 3000 people. Having been criticized by the government and urban residents for demanding money, in late 1999 the protestors changed their demand to the decommissioning of the dam. By doing so, they are trying to show that they are fighting for life; not simply monetary compensation. "

The World Commission on Dams Report is a greenie-orientated piece of garbage with mis-leading statements, biased opinions and lots of psuedo-science. As an example, it takes the worst possible scenario (a large, shallow dam in the tropics with a tiny hydro-station) and comes out with a statement that in some cases hydro dams produce as much CO2 as the equivalent coal-fired station, without mentioning that the CO2 comes from rotting vegetation that would otherwise be washed out to sea to rot there.

Every environmental effect is seen as a negative, such as a west coast South Island of NZ dam which has reduced the huge storm-surge flows, stabilising the river, to the detriment of a water-fowl, but to the benefit of trout. Guess which the locals prefer, besides not having the river change course occasionally, washing away homes and farms. If you havn't been there, it is hard to appreciate the huge volumes of rain and the power of the rivers - bridges have signs warning NOT to stop to take photos of the storm because a wall of water higher than the bridge may well wash you to your death.

As for the un-reliability of production, this has something to do with what is called the wet season. Yep, it's not year round, but it's pretty regular and predictable.

When a country produces more of a commodity than it consumes, this is called an export. Some people look on this as a good thing for any number of reasons.

You Sir, are trying to be deliberately misleading. The World Commission on Dams was set up with the help of the world Bank and World Conservation Union and published its report under the United Nations Environment Programme. Sure, all very greeny, tree-hugging leftists troublemakers...

The WCD report was the first study that pointed out the potential issues of CO2 and Methane emissions by dams particular in the tropics. The WCD report did at the time say that because the sample they looked at was very small their numbers only apply to the dams they assessed and that further research is needed. Rather than relying on your opinionated drivel I suggest anyone interested to actually read through the World Commission on Dams report.

The rotting vegetation by the way is not just that which would be washed down the river annually anyway but to a large extent the vegetation submerged by filling the dam initially. Further, not being a Chemist, I hazard a guess, that the chemical processes in decomposing the organic matter differ somehow between rotting in a fresh-water dam and rotting out on sea in salt-water and hence the amounts of CO2 and Methane released. Rather than seeing the WCD report as 'pseudo-science' like you suggest, further studies have been conducted since and largely agreed with the findings of the WCD report and delivering better and more data on the emissions of dams. The latest study looking at 85 reservoirs has been published in June 2011 in Nature Geoscience, Carbon emission from hydroelectric reservoirs linked to reservoir age and latitude.

[OzMick]

The World Commission on Dams Report is a greenie-orientated piece of garbage with mis-leading statements, biased opinions and lots of psuedo-science. As an example, it takes the worst possible scenario (a large, shallow dam in the tropics with a tiny hydro-station) and comes out with a statement that in some cases hydro dams produce as much CO2 as the equivalent coal-fired station, without mentioning that the CO2 comes from rotting vegetation that would otherwise be washed out to sea to rot there.

Every environmental effect is seen as a negative, such as a west coast South Island of NZ dam which has reduced the huge storm-surge flows, stabilising the river, to the detriment of a water-fowl, but to the benefit of trout. Guess which the locals prefer, besides not having the river change course occasionally, washing away homes and farms. If you havn't been there, it is hard to appreciate the huge volumes of rain and the power of the rivers - bridges have signs warning NOT to stop to take photos of the storm because a wall of water higher than the bridge may well wash you to your death.

As for the un-reliability of production, this has something to do with what is called the wet season. Yep, it's not year round, but it's pretty regular and predictable.

When a country produces more of a commodity than it consumes, this is called an export. Some people look on this as a good thing for any number of reasons.

You Sir, are trying to be deliberately misleading. The World Commission on Dams was set up with the help of the world Bank and World Conservation Union and published its report under the United Nations Environment Programme. Sure, all very greeny, tree-hugging leftists troublemakers...

The WCD report was the first study that pointed out the potential issues of CO2 and Methane emissions by dams particular in the tropics. The WCD report did at the time say that because the sample they looked at was very small their numbers only apply to the dams they assessed and that further research is needed. Rather than relying on your opinionated drivel I suggest anyone interested to actually read through the World Commission on Dams report.

The rotting vegetation by the way is not just that which would be washed down the river annually anyway but to a large extent the vegetation submerged by filling the dam initially. Further, not being a Chemist, I hazard a guess, that the chemical processes in decomposing the organic matter differ somehow between rotting in a fresh-water dam and rotting out on sea in salt-water and hence the amounts of CO2 and Methane released. Rather than seeing the WCD report as 'pseudo-science' like you suggest, further studies have been conducted since and largely agreed with the findings of the WCD report and delivering better and more data on the emissions of dams. The latest study looking at 85 reservoirs has been published in June 2011 in Nature Geoscience, Carbon emission from hydroelectric reservoirs linked to reservoir age and latitude.

You are right about one thing, you are not a chemist. First, the chemical breakdown process is the same in fresh and salt water. Second, carbon is elemental and is neither created nor destroyed outside of nuclear fission or fusion.To have CO2 and methane emissions you need to have a source of carbon and as this is a valuable resource, people do not build dams on top of a carbon source. There will be carbon in the vegetable matter that is initially flooded, but not a great deal - if they were flooding a forest they would utilise this resource rather than waste it. The original carbon is a one-off, once it rots away the ONLY renewable source of carbon is vegetable matter washed in by the river(s) feeding the dam. Measuring the CO2 output is a waste of time, energy and money as the bloody stuff was going to rot anyway. The only practical use for the data is to throw dis-ingenuous facts and figures about to discredit hydro-dams. Passing water through a turbine does not produce one fart-bubble of CO2, and the emissions would still be there if the dam was purely storage or flood mitigation.

I have read the WDR and will look at your article later - the link is not functioning. But it will interesting to see if they mention even one non-hydro dam as base-line data. Given the title, I suspect not, and it is my opinion that given 2 identical dams. the SAME dam used for hydro power one year, and no power generation the following, that the emissions would be near enough to identical. You might consider that opiniated drivel, I call it Science 101, which you obviously didn't bother attending.

Modern coal-fired power stations work at around 40% thermal efficiency, achieving approximately 2.5 MWhr/tonne of black coal. Pak Mun dam had an annual output of 290,000 MWhr, the equivalent of burning 700,000 tonnes of coal per year. The World Dams Report gave that misleading example of the Brazilian dam, and it has grabbed by greenie idiots, who know very little chemistry and SFA about power generation, ever since to claim that hydro dams "may" put out the same CO2 emissions as a coal-fired station. It is nothing but horse-shit !

[maidu]

I agree that a fish ladder would probably work if designed well, and IF the migrating fish were allowed to climb it unhampered. I doubt either condition exists at Pak Mun.

[TerraPosse]

The World Commission on Dams Report is a greenie-orientated piece of garbage with mis-leading statements, biased opinions and lots of psuedo-science. As an example, it takes the worst possible scenario (a large, shallow dam in the tropics with a tiny hydro-station) and comes out with a statement that in some cases hydro dams produce as much CO2 as the equivalent coal-fired station, without mentioning that the CO2 comes from rotting vegetation that would otherwise be washed out to sea to rot there.

Every environmental effect is seen as a negative, such as a west coast South Island of NZ dam which has reduced the huge storm-surge flows, stabilising the river, to the detriment of a water-fowl, but to the benefit of trout. Guess which the locals prefer, besides not having the river change course occasionally, washing away homes and farms. If you havn't been there, it is hard to appreciate the huge volumes of rain and the power of the rivers - bridges have signs warning NOT to stop to take photos of the storm because a wall of water higher than the bridge may well wash you to your death.

As for the un-reliability of production, this has something to do with what is called the wet season. Yep, it's not year round, but it's pretty regular and predictable.

When a country produces more of a commodity than it consumes, this is called an export. Some people look on this as a good thing for any number of reasons.

You Sir, are trying to be deliberately misleading. The World Commission on Dams was set up with the help of the world Bank and World Conservation Union and published its report under the United Nations Environment Programme. Sure, all very greeny, tree-hugging leftists troublemakers...

The WCD report was the first study that pointed out the potential issues of CO2 and Methane emissions by dams particular in the tropics. The WCD report did at the time say that because the sample they looked at was very small their numbers only apply to the dams they assessed and that further research is needed. Rather than relying on your opinionated drivel I suggest anyone interested to actually read through the World Commission on Dams report.

The rotting vegetation by the way is not just that which would be washed down the river annually anyway but to a large extent the vegetation submerged by filling the dam initially. Further, not being a Chemist, I hazard a guess, that the chemical processes in decomposing the organic matter differ somehow between rotting in a fresh-water dam and rotting out on sea in salt-water and hence the amounts of CO2 and Methane released. Rather than seeing the WCD report as 'pseudo-science' like you suggest, further studies have been conducted since and largely agreed with the findings of the WCD report and delivering better and more data on the emissions of dams. The latest study looking at 85 reservoirs has been published in June 2011 in Nature Geoscience, Carbon emission from hydroelectric reservoirs linked to reservoir age and latitude.

You are right about one thing, you are not a chemist. First, the chemical breakdown process is the same in fresh and salt water. Second, carbon is elemental and is neither created nor destroyed outside of nuclear fission or fusion.To have CO2 and methane emissions you need to have a source of carbon and as this is a valuable resource, people do not build dams on top of a carbon source. There will be carbon in the vegetable matter that is initially flooded, but not a great deal - if they were flooding a forest they would utilise this resource rather than waste it. The original carbon is a one-off, once it rots away the ONLY renewable source of carbon is vegetable matter washed in by the river(s) feeding the dam. Measuring the CO2 output is a waste of time, energy and money as the bloody stuff was going to rot anyway. The only practical use for the data is to throw dis-ingenuous facts and figures about to discredit hydro-dams. Passing water through a turbine does not produce one fart-bubble of CO2, and the emissions would still be there if the dam was purely storage or flood mitigation.

I have read the WDR and will look at your article later - the link is not functioning. But it will interesting to see if they mention even one non-hydro dam as base-line data. Given the title, I suspect not, and it is my opinion that given 2 identical dams. the SAME dam used for hydro power one year, and no power generation the following, that the emissions would be near enough to identical. You might consider that opiniated drivel, I call it Science 101, which you obviously didn't bother attending.

Modern coal-fired power stations work at around 40% thermal efficiency, achieving approximately 2.5 MWhr/tonne of black coal. Pak Mun dam had an annual output of 290,000 MWhr, the equivalent of burning 700,000 tonnes of coal per year. The World Dams Report gave that misleading example of the Brazilian dam, and it has grabbed by greenie idiots, who know very little chemistry and SFA about power generation, ever since to claim that hydro dams "may" put out the same CO2 emissions as a coal-fired station. It is nothing but horse-shit !

The WCD report never set out to discredit hydro-dams, merely highlight the issues associated with them and how to alleviate them. The authors of the report certainly don't appear anti-hydro but they wouldn't have done a good report if they had just ignored/swept-under-the-carpet the many potential environmental and sociological problems encountered by many hydro-dam schemes. I'm all for hydro-power...where it is appropriate. And not everywhere where it's technical feasible is it also appropriate.

I have no doubt the breakdown processes are similar in fresh and salt water but I have doubts they are exactly the same. For once the amount of CO2 that can be absorbed by water is different between salt and fresh water with fresh water actually being able to absorb more CO2 than salt water. Although temperature, ph-value and various other factors can greatly influence that ability and therefore cause different levels of emissions at different times. As a result of these differences it would differ if the organic matter is broken down in the sea or in a dam.

You are correct of course that these emissions apply to dams/reservoirs irrespective of power generation or not. None of the research I have seen claims the emissions are a result of the power generation, just that most and the biggest dams happen to be hydro-power ones and therefore the emissions are related of the generated output. If they'd look at a dam that is just a water reservoir than there would of course be no point comparing its emissions to another source of power generation with nothing being generated by the dam. Simple really.

Again you're very disingenuous regarding the amount of organic matter submerged by large dam projects. Below is just one example I know personally quite well but there are many more. This is the Kariba dam, the largest dam in the world at its completion. Doesn't look like they bothered much to utilise that valuable carbon resource before flooding, does it?

The organic matter submerged by the initial flooding will release CO2 and Methane for quite some time. How long and how much is the subject of some of the research started as a result of the findings by the WCD. Btw., the link seems to work fine for me. If not you can find the article on the Nature Geoscience website (published 31 July 2011). The emission amounts indeed are not as severe as was indicated in the WCD report but there are quite a number of factors that influence these values.

Edited August 18, 2011 by TerraPosse

[TerraPosse]

hhmmm...double posted somehow..

Edited August 18, 2011 by TerraPosse

[OzMick]

The World Commission on Dams Report is a greenie-orientated piece of garbage with mis-leading statements, biased opinions and lots of psuedo-science. As an example, it takes the worst possible scenario (a large, shallow dam in the tropics with a tiny hydro-station) and comes out with a statement that in some cases hydro dams produce as much CO2 as the equivalent coal-fired station, without mentioning that the CO2 comes from rotting vegetation that would otherwise be washed out to sea to rot there.

Every environmental effect is seen as a negative, such as a west coast South Island of NZ dam which has reduced the huge storm-surge flows, stabilising the river, to the detriment of a water-fowl, but to the benefit of trout. Guess which the locals prefer, besides not having the river change course occasionally, washing away homes and farms. If you havn't been there, it is hard to appreciate the huge volumes of rain and the power of the rivers - bridges have signs warning NOT to stop to take photos of the storm because a wall of water higher than the bridge may well wash you to your death.

As for the un-reliability of production, this has something to do with what is called the wet season. Yep, it's not year round, but it's pretty regular and predictable.

When a country produces more of a commodity than it consumes, this is called an export. Some people look on this as a good thing for any number of reasons.

You Sir, are trying to be deliberately misleading. The World Commission on Dams was set up with the help of the world Bank and World Conservation Union and published its report under the United Nations Environment Programme. Sure, all very greeny, tree-hugging leftists troublemakers...

The WCD report was the first study that pointed out the potential issues of CO2 and Methane emissions by dams particular in the tropics. The WCD report did at the time say that because the sample they looked at was very small their numbers only apply to the dams they assessed and that further research is needed. Rather than relying on your opinionated drivel I suggest anyone interested to actually read through the World Commission on Dams report.

The rotting vegetation by the way is not just that which would be washed down the river annually anyway but to a large extent the vegetation submerged by filling the dam initially. Further, not being a Chemist, I hazard a guess, that the chemical processes in decomposing the organic matter differ somehow between rotting in a fresh-water dam and rotting out on sea in salt-water and hence the amounts of CO2 and Methane released. Rather than seeing the WCD report as 'pseudo-science' like you suggest, further studies have been conducted since and largely agreed with the findings of the WCD report and delivering better and more data on the emissions of dams. The latest study looking at 85 reservoirs has been published in June 2011 in Nature Geoscience, Carbon emission from hydroelectric reservoirs linked to reservoir age and latitude.

You are right about one thing, you are not a chemist. First, the chemical breakdown process is the same in fresh and salt water. Second, carbon is elemental and is neither created nor destroyed outside of nuclear fission or fusion.To have CO2 and methane emissions you need to have a source of carbon and as this is a valuable resource, people do not build dams on top of a carbon source. There will be carbon in the vegetable matter that is initially flooded, but not a great deal - if they were flooding a forest they would utilise this resource rather than waste it. The original carbon is a one-off, once it rots away the ONLY renewable source of carbon is vegetable matter washed in by the river(s) feeding the dam. Measuring the CO2 output is a waste of time, energy and money as the bloody stuff was going to rot anyway. The only practical use for the data is to throw dis-ingenuous facts and figures about to discredit hydro-dams. Passing water through a turbine does not produce one fart-bubble of CO2, and the emissions would still be there if the dam was purely storage or flood mitigation.

I have read the WDR and will look at your article later - the link is not functioning. But it will interesting to see if they mention even one non-hydro dam as base-line data. Given the title, I suspect not, and it is my opinion that given 2 identical dams. the SAME dam used for hydro power one year, and no power generation the following, that the emissions would be near enough to identical. You might consider that opiniated drivel, I call it Science 101, which you obviously didn't bother attending.

Modern coal-fired power stations work at around 40% thermal efficiency, achieving approximately 2.5 MWhr/tonne of black coal. Pak Mun dam had an annual output of 290,000 MWhr, the equivalent of burning 700,000 tonnes of coal per year. The World Dams Report gave that misleading example of the Brazilian dam, and it has grabbed by greenie idiots, who know very little chemistry and SFA about power generation, ever since to claim that hydro dams "may" put out the same CO2 emissions as a coal-fired station. It is nothing but horse-shit !

The WCD report never set out to discredit hydro-dams, merely highlight the issues associated with them and how to alleviate them. The authors of the report certainly don't appear anti-hydro but they wouldn't have done a good report if they had just ignored/swept-under-the-carpet the many potential environmental and sociological problems encountered by many hydro-dam schemes. I'm all for hydro-power...where it is appropriate. And not everywhere where it's technical feasible is it also appropriate.

I have no doubt the breakdown processes are similar in fresh and salt water but I have doubts they are exactly the same. For once the amount of CO2 that can be absorbed by water is different between salt and fresh water with fresh water actually being able to absorb more CO2 than salt water. Although temperature, ph-value and various other factors can greatly influence that ability and therefore cause different levels of emissions at different times. As a result of these differences it would differ if the organic matter is broken down in the sea or in a dam.

You are correct of course that these emissions apply to dams/reservoirs irrespective of power generation or not. None of the research I have seen claims the emissions are a result of the power generation, just that most and the biggest dams happen to be hydro-power ones and therefore the emissions are related of the generated output. If they'd look at a dam that is just a water reservoir than there would of course be no point comparing its emissions to another source of power generation with nothing being generated by the dam. Simple really.

Again you're very disingenuous regarding the amount of organic matter submerged by large dam projects. Below is just one example I know personally quite well but there are many more. This is the Kariba dam, the largest dam in the world at its completion. Doesn't look like they bothered much to utilise that valuable carbon resource before flooding, does it?

The organic matter submerged by the initial flooding will release CO2 and Methane for quite some time. How long and how much is the subject of some of the research started as a result of the findings by the WCD. Btw., the link seems to work fine for me. If not you can find the article on the Nature Geoscience website (published 31 July 2011). The emission amounts indeed are not as severe as was indicated in the WCD report but there are quite a number of factors that influence these values.

You just don't get it do you? If fresh water holds CO2 better than salt, what does it matter, eventually it will reach the ocean. Whether the dam is being used for power generation or not is irrelevant because the dam will produce the same emissions, so why bother comparing them to other sources of power. There is only one possible reason, to denigrate hydro-power dams - they put out CO2 emissions and the WDR says it is equivalent to coal-fired power stations IN SOME CASES, without ever explaining the facts.

The amount of carbon in a flooded area is simply too minor to consider, other wise it would be utilised. I know what the factors as to the release rate, temperature mainly, but as it ALL will be released over the life of the dam, and it is very little to start with, it is not worth considering.

Yes the WDR went deeply into sociological and environmental effects OF HYDRO DAMS, and rarely came out with a positive, such as the NZ case that I highlighted. IMHO opinion, that is bias. If they has mentioned Tasmania, they would have found that draining/destroying the dams would have killed thousands of platypi, an endangered species that thrive on the dam banks - besides the fact of thousands of Gigawatts of pollution free power.

I have tried to explain this to you in the past, and I will enter into no further reply - HYDRO POWER GENERATION IS POLLUTION FREE OTHER THAN THAT WHICH WILL OCCUR NATURALLY

[TerraPosse]

The WCD report never set out to discredit hydro-dams, merely highlight the issues associated with them and how to alleviate them. The authors of the report certainly don't appear anti-hydro but they wouldn't have done a good report if they had just ignored/swept-under-the-carpet the many potential environmental and sociological problems encountered by many hydro-dam schemes. I'm all for hydro-power...where it is appropriate. And not everywhere where it's technical feasible is it also appropriate.

I have no doubt the breakdown processes are similar in fresh and salt water but I have doubts they are exactly the same. For once the amount of CO2 that can be absorbed by water is different between salt and fresh water with fresh water actually being able to absorb more CO2 than salt water. Although temperature, ph-value and various other factors can greatly influence that ability and therefore cause different levels of emissions at different times. As a result of these differences it would differ if the organic matter is broken down in the sea or in a dam.

You are correct of course that these emissions apply to dams/reservoirs irrespective of power generation or not. None of the research I have seen claims the emissions are a result of the power generation, just that most and the biggest dams happen to be hydro-power ones and therefore the emissions are related of the generated output. If they'd look at a dam that is just a water reservoir than there would of course be no point comparing its emissions to another source of power generation with nothing being generated by the dam. Simple really.

Again you're very disingenuous regarding the amount of organic matter submerged by large dam projects. Below is just one example I know personally quite well but there are many more. This is the Kariba dam, the largest dam in the world at its completion. Doesn't look like they bothered much to utilise that valuable carbon resource before flooding, does it?

The organic matter submerged by the initial flooding will release CO2 and Methane for quite some time. How long and how much is the subject of some of the research started as a result of the findings by the WCD. Btw., the link seems to work fine for me. If not you can find the article on the Nature Geoscience website (published 31 July 2011). The emission amounts indeed are not as severe as was indicated in the WCD report but there are quite a number of factors that influence these values.

You just don't get it do you? If fresh water holds CO2 better than salt, what does it matter, eventually it will reach the ocean. Whether the dam is being used for power generation or not is irrelevant because the dam will produce the same emissions, so why bother comparing them to other sources of power. There is only one possible reason, to denigrate hydro-power dams - they put out CO2 emissions and the WDR says it is equivalent to coal-fired power stations IN SOME CASES, without ever explaining the facts.

The amount of carbon in a flooded area is simply too minor to consider, other wise it would be utilised. I know what the factors as to the release rate, temperature mainly, but as it ALL will be released over the life of the dam, and it is very little to start with, it is not worth considering.

Yes the WDR went deeply into sociological and environmental effects OF HYDRO DAMS, and rarely came out with a positive, such as the NZ case that I highlighted. IMHO opinion, that is bias. If they has mentioned Tasmania, they would have found that draining/destroying the dams would have killed thousands of platypi, an endangered species that thrive on the dam banks - besides the fact of thousands of Gigawatts of pollution free power.

I have tried to explain this to you in the past, and I will enter into no further reply - HYDRO POWER GENERATION IS POLLUTION FREE OTHER THAN THAT WHICH WILL OCCUR NATURALLY

Somehow you don't seem to get that substantial amounts of organic matter submerged by dams release CO2 and Methane that would not be released had the dams not been build, therefore it is NOT occurring naturally (and we're are talking valleys of forests like my example of the Kariba dam shows, so no small beer like you are trying to paint it). To claim it is, is grossly misleading (as you have been trying to do repeatedly). Not really that complicated or surprising. Neither is the observation that this affects dams build in the tropics much more than those in temperate zones (where this is negligible according to some Swiss research published recently about dams in the Alps). You can shout as much as you want that doesn't change the facts and I do trust the figures and observations collected and published by scientists in their field more than the ramblings of some dude on the 'nternet. And that does include the contributors to the report of the WCD. And frankly I haven't seen or heard of anyone yet who actually disputed those findings in principle.

[OzMick]

The WCD report never set out to discredit hydro-dams, merely highlight the issues associated with them and how to alleviate them. The authors of the report certainly don't appear anti-hydro but they wouldn't have done a good report if they had just ignored/swept-under-the-carpet the many potential environmental and sociological problems encountered by many hydro-dam schemes. I'm all for hydro-power...where it is appropriate. And not everywhere where it's technical feasible is it also appropriate.

I have no doubt the breakdown processes are similar in fresh and salt water but I have doubts they are exactly the same. For once the amount of CO2 that can be absorbed by water is different between salt and fresh water with fresh water actually being able to absorb more CO2 than salt water. Although temperature, ph-value and various other factors can greatly influence that ability and therefore cause different levels of emissions at different times. As a result of these differences it would differ if the organic matter is broken down in the sea or in a dam.

You are correct of course that these emissions apply to dams/reservoirs irrespective of power generation or not. None of the research I have seen claims the emissions are a result of the power generation, just that most and the biggest dams happen to be hydro-power ones and therefore the emissions are related of the generated output. If they'd look at a dam that is just a water reservoir than there would of course be no point comparing its emissions to another source of power generation with nothing being generated by the dam. Simple really.

Again you're very disingenuous regarding the amount of organic matter submerged by large dam projects. Below is just one example I know personally quite well but there are many more. This is the Kariba dam, the largest dam in the world at its completion. Doesn't look like they bothered much to utilise that valuable carbon resource before flooding, does it?

The organic matter submerged by the initial flooding will release CO2 and Methane for quite some time. How long and how much is the subject of some of the research started as a result of the findings by the WCD. Btw., the link seems to work fine for me. If not you can find the article on the Nature Geoscience website (published 31 July 2011). The emission amounts indeed are not as severe as was indicated in the WCD report but there are quite a number of factors that influence these values.

You just don't get it do you? If fresh water holds CO2 better than salt, what does it matter, eventually it will reach the ocean. Whether the dam is being used for power generation or not is irrelevant because the dam will produce the same emissions, so why bother comparing them to other sources of power. There is only one possible reason, to denigrate hydro-power dams - they put out CO2 emissions and the WDR says it is equivalent to coal-fired power stations IN SOME CASES, without ever explaining the facts.

The amount of carbon in a flooded area is simply too minor to consider, other wise it would be utilised. I know what the factors as to the release rate, temperature mainly, but as it ALL will be released over the life of the dam, and it is very little to start with, it is not worth considering.

Yes the WDR went deeply into sociological and environmental effects OF HYDRO DAMS, and rarely came out with a positive, such as the NZ case that I highlighted. IMHO opinion, that is bias. If they has mentioned Tasmania, they would have found that draining/destroying the dams would have killed thousands of platypi, an endangered species that thrive on the dam banks - besides the fact of thousands of Gigawatts of pollution free power.

I have tried to explain this to you in the past, and I will enter into no further reply - HYDRO POWER GENERATION IS POLLUTION FREE OTHER THAN THAT WHICH WILL OCCUR NATURALLY

Somehow you don't seem to get that substantial amounts of organic matter submerged by dams release CO2 and Methane that would not be released had the dams not been build, therefore it is NOT occurring naturally (and we're are talking valleys of forests like my example of the Kariba dam shows, so no small beer like you are trying to paint it). To claim it is, is grossly misleading (as you have been trying to do repeatedly). Not really that complicated or surprising. Neither is the observation that this affects dams build in the tropics much more than those in temperate zones (where this is negligible according to some Swiss research published recently about dams in the Alps). You can shout as much as you want that doesn't change the facts and I do trust the figures and observations collected and published by scientists in their field more than the ramblings of some dude on the 'nternet. And that does include the contributors to the report of the WCD. And frankly I haven't seen or heard of anyone yet who actually disputed those findings in principle.

Take all the timber, grass and other crap under the Kariba Dam, remove all the water in its material ie dry it (most of the mass), then compress it for a few millenia - and you will get a few ton of coal. Then compare that to Pak Mun equivalent of 700,000 tonnes/year for the next 50 years or so. It is not small beer, it approaches SFA. And that ignores the fact that none of it was immortal and would eventually oxidise anyway.

How many times do you have to be told that dams in the tropics have higher levels of biomass washed into them, and that it is IRRELEVANT. CO2 emissions of dams in the alps are negligible - but why were they measured in the first place. Because people with an axe to grind will throw stupid and irrelevant facts at scientifically ignorant greenies who will come out with the message that "dams are BAD".

What does the dude on the Internet stand to gain from this? Am I trying to sell you glossy magazines full of glossy pictures and idiot science?

[TerraPosse]

The WCD report never set out to discredit hydro-dams, merely highlight the issues associated with them and how to alleviate them. The authors of the report certainly don't appear anti-hydro but they wouldn't have done a good report if they had just ignored/swept-under-the-carpet the many potential environmental and sociological problems encountered by many hydro-dam schemes. I'm all for hydro-power...where it is appropriate. And not everywhere where it's technical feasible is it also appropriate.

I have no doubt the breakdown processes are similar in fresh and salt water but I have doubts they are exactly the same. For once the amount of CO2 that can be absorbed by water is different between salt and fresh water with fresh water actually being able to absorb more CO2 than salt water. Although temperature, ph-value and various other factors can greatly influence that ability and therefore cause different levels of emissions at different times. As a result of these differences it would differ if the organic matter is broken down in the sea or in a dam.

You are correct of course that these emissions apply to dams/reservoirs irrespective of power generation or not. None of the research I have seen claims the emissions are a result of the power generation, just that most and the biggest dams happen to be hydro-power ones and therefore the emissions are related of the generated output. If they'd look at a dam that is just a water reservoir than there would of course be no point comparing its emissions to another source of power generation with nothing being generated by the dam. Simple really.

Again you're very disingenuous regarding the amount of organic matter submerged by large dam projects. Below is just one example I know personally quite well but there are many more. This is the Kariba dam, the largest dam in the world at its completion. Doesn't look like they bothered much to utilise that valuable carbon resource before flooding, does it?

The organic matter submerged by the initial flooding will release CO2 and Methane for quite some time. How long and how much is the subject of some of the research started as a result of the findings by the WCD. Btw., the link seems to work fine for me. If not you can find the article on the Nature Geoscience website (published 31 July 2011). The emission amounts indeed are not as severe as was indicated in the WCD report but there are quite a number of factors that influence these values.

You just don't get it do you? If fresh water holds CO2 better than salt, what does it matter, eventually it will reach the ocean. Whether the dam is being used for power generation or not is irrelevant because the dam will produce the same emissions, so why bother comparing them to other sources of power. There is only one possible reason, to denigrate hydro-power dams - they put out CO2 emissions and the WDR says it is equivalent to coal-fired power stations IN SOME CASES, without ever explaining the facts.

The amount of carbon in a flooded area is simply too minor to consider, other wise it would be utilised. I know what the factors as to the release rate, temperature mainly, but as it ALL will be released over the life of the dam, and it is very little to start with, it is not worth considering.

Yes the WDR went deeply into sociological and environmental effects OF HYDRO DAMS, and rarely came out with a positive, such as the NZ case that I highlighted. IMHO opinion, that is bias. If they has mentioned Tasmania, they would have found that draining/destroying the dams would have killed thousands of platypi, an endangered species that thrive on the dam banks - besides the fact of thousands of Gigawatts of pollution free power.

I have tried to explain this to you in the past, and I will enter into no further reply - HYDRO POWER GENERATION IS POLLUTION FREE OTHER THAN THAT WHICH WILL OCCUR NATURALLY

Somehow you don't seem to get that substantial amounts of organic matter submerged by dams release CO2 and Methane that would not be released had the dams not been build, therefore it is NOT occurring naturally (and we're are talking valleys of forests like my example of the Kariba dam shows, so no small beer like you are trying to paint it). To claim it is, is grossly misleading (as you have been trying to do repeatedly). Not really that complicated or surprising. Neither is the observation that this affects dams build in the tropics much more than those in temperate zones (where this is negligible according to some Swiss research published recently about dams in the Alps). You can shout as much as you want that doesn't change the facts and I do trust the figures and observations collected and published by scientists in their field more than the ramblings of some dude on the 'nternet. And that does include the contributors to the report of the WCD. And frankly I haven't seen or heard of anyone yet who actually disputed those findings in principle.

Take all the timber, grass and other crap under the Kariba Dam, remove all the water in its material ie dry it (most of the mass), then compress it for a few millenia - and you will get a few ton of coal. Then compare that to Pak Mun equivalent of 700,000 tonnes/year for the next 50 years or so. It is not small beer, it approaches SFA. And that ignores the fact that none of it was immortal and would eventually oxidise anyway.

How many times do you have to be told that dams in the tropics have higher levels of biomass washed into them, and that it is IRRELEVANT. CO2 emissions of dams in the alps are negligible - but why were they measured in the first place. Because people with an axe to grind will throw stupid and irrelevant facts at scientifically ignorant greenies who will come out with the message that "dams are BAD".

What does the dude on the Internet stand to gain from this? Am I trying to sell you glossy magazines full of glossy pictures and idiot science?

I have no idea what you gain by trying to deny the bleeding obvious and I'm not even going to try and fathom. There is a wee bit of a difference between breaking down organic matter in large man-made water-filled structure and releasing greenhouse gases over the space of a century into our atmosphere or seal it off in its natural environment and 'make' coal over millenia, as you describe. One of these is currently messing about with an essential part of our live support on this rock in space, the other one is no bother. Again you are trying to obfuscate and blur the issues at hand.

Those emissions caused by dams in the tropics are anything but irrelevant which is why scientists do take a closer look at the actual levels and the factors that influence them. Just because you would like them to be irrelevant doesn't make that a fact. Again, I'm not aware of anyone denying or arguing the relevance of these emissions taking place, with the notable exception of you for whatever reasons.

The recent study on dams in the Alps again was not a waste of time and resources either but a follow-up to an earlier one that had dams in the Alps, in a temperate zone, emit unexpected high levels of greenhouse gases. The more detailed study published recently then found the levels to be lower and more in line with what was expected (I don't post a link since I have only seen the German version of it). Now, that is science at work. No panic, factual, transparent and without shouting at the top of ones voice down that-which-cannot-be in ones own little view of the world.

Dams and hydro-power schemes are not bad per se. They can be a force for good. Just many of those build in the past do not deliver the benefits promised whilst their impacts outweigh any benefits received (of which the release of CO2 and Methane is only a minor issue). That is exactly what the WDR set out to rectify by showing the pitfalls to avoid when implementing dam projects. I'm in favour of any use of renewable energy sources at our disposal. That doesn't mean though I blend out the various issues and problems associated with them.

[SantiSuk]

The opinion that the world bank-funded power generation scheme is uneconomic, if true, seems to be as big a scandal as the environmental issues debated above. As usual, nobody will be brought to account even if there has been a huge waste of development aid funds.

[Humphrey Bear]

I don't wish to make this too long, so I haven't replied to any particular post.

With regard to vegetation - every tree, every plant that grows will eventually die and rot, thus emitting CO2 and methane. The problem with building a dam is that this will happen to all vegetation within the footprint of the reservoir at one time, instead of being spread over a period of time. But once rotted there will be no more growth, so the overall amount of CO2/methane over a forty-fifty year period (the basic life of the power generators) will be no more than the natural emissions and may be less.

The vegetation trapped by the dam, which vegetation would normally flow downstream to the sea - water hyacinth and other debris - will cause higher levels of emissions at the dam, but there will be lower amounts downstream, where these plants are no longer present.

The sum total of all this - over a period of time - is that the same amount of vegetation will rot, emitting the same amount of carbon gases, whether the dam is there or not. It is simple logic.

Small hydro-generators are useful for local electricity supply, if the national grid is not sited within the catchment of the power plant.

If it is connected to the grid, then it can make a useful contribution during peak times as a 'fill-in' power plant. The big power plants - gas or coal-fired - take a long time to come up to baseload and to deliver power efficiently, so they are run as the main feeders on the grid pretty much all the time. At peak periods the smaller power plants, including a lot of small hydro-plants, can be brought on immediately, as they do not need to build up steam under pressure to generate power.

All these types of power plant have their different uses and all are necessary for a balanced grid to supply consumers when demand is created.