Expert analysis of geological disasters in 2010
Written by WANG Yongchen.Pictures by YANG Yong
The Decade River Project 2010 will deal with two main topics: drought in Southwest China, and Southwest China's recent geological disasters.
Fan Xiao is chief engineer at the Sichuan Bureau of Geology and Mineral Exploration and was the first geologist to suspect that the Wenchuan earthquake might be linked with the development of Zipingpu hydroelectric power station. He is interviewed by the Decade River Project every year and on December 7, 2010 – the last day of this year's project – Zhao Lanjian and I had the chance to catch up with him.
In answer to our questions concerning geological disasters in the Southwest region and issues raised by river development, Fan Xiao said the following:
Fan Xiao: Earthquakes can cause immense destruction. If you look at the land after an earthquake, it is as if its stomach has been cut open and its intestines have poured out: fields of vegetation and whole forests have been destroyed, hills and mountains have collapsed. According to an estimate based on analysis of photos taken from airplanes near to Yingxiu in the aftermath of the Wenchuan earthquake, more than 75% of the area was affected, either by mountain collapse, landslides and debris flow, or the destruction of vegetation. Less than 30% of the region was left unaffected by the earthquake.
There was, therefore, a significant impact on local ecology; landslides, avalanches, and debris flow will likely follow heavy rain. Investigations were conducted after the earthquake to find out all the potential geological hazards in the area and to make a record of them.
When it came to reconstruction after the earthquake, however, we put too much emphasis on speed. The slogan was “we can complete three years of reconstruction in two years time”. This meant that houses were rebuilt first, but tools for post-earthquake management were not ready on time. This was the case in Yingxiu and Qingping (which suffered serious landslides in 2010), where earthquake prevention and response systems had not been set up.
There was a further problem with the nature of post-earthquake reconstruction. Previously people’s homes were scattered across various areas, whilst now their settlements have been condensed, meaning that each settlement covers a greater surface area. Since there are a limited number of suitably large sites in the western region, areas along the river shore and even places at serious risk of earthquake damage have been used for housing, as is the case in Qingping.
Wang Yongchen: Houses in Hanyuan were also rebuilt in dangerous locations, such as areas at risk from landslides.
Fan Xiao: Exactly, it’s just as I said. In the past, no buildings were found there because of the frequent danger of falling stones.
Zhao Lanjian (Phoenix): Locals usually do not even walk past these areas, because they have long been aware of the risk of falling stones.
Fan Xiao: In the past no one would build their houses there, and yet during settlement reconstruction it was suggested that entire villages be moved there. Some experts were against them, but the proposals were carried out regardless because the river valleys were flooded.Flooding meant that mountains and other such dangerous locations were the only places available for reconstruction.
Of course, more thorough assessment should have been done. For instance, research into the new location for Hanyuan was not conducted in sufficient depth. A lack of understanding of landslides led to many problems arising after houses had been built there.
Fan Xiao: Quite a few houses at Luobugang in the new Hanyuan are situated on slopes.
Wang Yongchen: We went there last year, but this year we were not able to enter.
Fan Xiao: The entire new Hanyuan has been moved there.
Wang Yongchen: Today when I was writing about rivers, I read an article published in Southern Weekend about landslides in Hanyuan. What you just mentioned was also covered in the report.
Zhaolan Jian: The landslide that happened in Wangong, Hanyuan, on July 27 this year?
Wang Yongchen: Yes. Mountains ranging from Wenchuan to Yingxiu have have been struck by very serious landslides, right?
Fan Xiao: There have been a great many disasters: landslides, avalanches, mudslides…
Wang Yongchen: What do you think will happen to the local landscape? For example, in the future might barrier lakes be constructed like those in Jiuzhaigou?
Fan Xiao: A barrier lake has already been built with a series of dams. A large barrier lake was put in place after the May 12 earthquake at Laohuzui, because landslides had changed the entire area geologically. Later on, however, the lake burst its banks and ran out of water. The local riverbed, though, has completely changed and has become a series of powerful rapids, out of which water flows and underneath which there is now a natural dam which actually functions as a barrier lake. This means that upstream water levels have risen, and that some houses have been flooded, as happened this year.
Wang Yongchen: Will it become a tourist attraction?
Fan Xiao: That is a definite possibility, but for the moment the lake is not in a stable condition, and it will not become stable in the next few years. Stabilization will take a dozen years at the very least, maybe even decades. After the May 12 earthquake, a natural stabilizing process would begin: during the wet season rainwater washes mud down after landslides and the ground below gradually becomes stable. In spite of this natural process, there are still some problems that need to be addressed. We should not put too much emphasis on political targets. For instance, since the land is not yet stable, it is not necessary to build roads and settlements too densely. We have already seen that newly-built roads and bridges are often damaged by landslides. This is an issue that needs to be addressed now. We should not promise that we will reconstruct over and over again after hundreds of landslides. Clearly this is not a sensible approach.
Wang Yongchen: Do you think that the Zipingpu power station is still under threat?
Fan Xiao: Definitely. It is still under maintenance. Since the earthquake, it still has not reached its highest water level.
Wang Yongchen: Is that not a tremendous waste?
Fan Xiao: Yes. After the earthquake the reservoir was not fully repaired. The other power stations under threat include those located in the lower reaches of the Jinsha River. Some of these power stations have not yet started storing water. As soon as water-storing starts, the situation will become very dangerous.
Zhao Lanjian: Recent news reports have only mentioned the benefits that dams bring.
Fan Xiao: Am I right in thinking that there have been no articles mentioning the negative impact of dams?
Zhao Lanjian: There have been very few, with only a couple of sentences devoted to their negative impact.
Wang Yongchen: The twelfth Five-Year Plan places a great deal of emphasis on the development of hydropower…
Fan Xiao: There is also a great deal of work being carried out in Tibet, with hydropower being developed on a large scale in the Brahmaputra valley. This might well be the only major valley in the world that remains in its original ecological state; like the Amazon River, it is one of a kind. Even in these final remaining untouched natural sites, people want to start construction projects and find new energy sources.
Wang Yongchen: Are there really no other options? Recently there have been many news reports about the construction of power stations in the Brahmaputra valley.
Fan Xiao: Even if roads are built there, cars can hardly enter because the risk of geological disasters is so severe. It is situated in the Himalayas, at the place where the roof of the world rises the most sharply. This is the original crossing between the Himalayas and the Indo-Gangetic Plain, where there is a huge drop. This is where the most acute topographical changes affecting the geology of the whole area are taking place, making it the least stable area. In the area where the Brahmaputra turns sharply, an earthquake of magnitude 8 or greater occurred in 1950, causing severe landslides. In addition, since the glaciers above were contemporary formations they slid down, just like a landslide. Normal glacier movement is so slow that people can hardly feel it.
Wang Yongchen: So the ice collapsed.
Fan Xiao: Ice came down like a landslide, blocking the Brahmaputra and forming dams made of ice. It also destroyed villages below, killing many people. Relatively speaking it is not a heavily populated area, but I still read in a news report that around 100 people died in one village.
Zhao Lanjian: In 1950?
Fan Xiao: In 1950 there were many earthquakes in that area; if dams were built there it would really be too dangerous. Of course, the damage to the natural ecology would be even more serious. There is an arctogaeic region that goes beyond normal latitudinal changes based in water channels running along the Brahmaputra, where the wildlife ranges from the tropical to the boreal. Since this is a change of altitude rather than of latitude, from around 5000 to around 7000 metres above sea level one can find wildlife normally only found in frigid zones. When one considers this change in altitude, one can see that nowhere else on earth has such a complete and varied range of species, and that nowhere else stands out quite so much or is quite as untouched as this area.
From an ecological point of view, nowhere in the world is comparable to this region. Our country has two major virgin forests: one is in Xing’anling in the North-East, and most of this forest has already been damaged; the other is in eastern Tibet and runs from the lower reaches of the Brahmaputra all the way to western Sichuan. Much of the forest in western Sichuan has already been felled, and whilst the area around Gongga Mountian has been fairly well preserved, the development of hydropower is now being promoted in this region.
The reason why the forest in the Brahmaputra basin has been relatively well preserved is simply that transportation is not practical. There has already been some deforestation in the area, but so far it has been limited. The construction of many hydroelectric power stations in the area would therefore represent a terrible ecological disaster.
Zhao Lanjian: Every year as I travel around interviewing people for the Decade River Project I feel an increasing sense of desperation.
Fan Xiao: Indeed. Plans for western China in Yunnan, Sichuan and Guizhou have all been finished, and all the construction plans from the Twelfth Five-Year Plan that were started are more or less complete; now even the upper reaches of the Jinsha River are being developed. Further development projects will extend to Tibet along the Jinsha River.
Fan Xiao: I am not saying that we should not use hydropower, but we should not develop entire rivers, not leaving a single drop of water untouched. The development of the South China Sea is now seen as problematic. Why? It was originally a National Nature Reserve because of rare species of fish from the upper reaches of the Yangtze River that are found there. It is the natural spawning site for these species of fish, it is their natural habitat, and helps maintain the gene pool of these species. There are over two hundred species of fish in the upper reaches of the Yangtze River. Maintaining the gene pool of so many species of fish and other aquatic wildlife is of global importance, particularly when one bears in the mind the size of the Yangtze River, which accounts for one eighth of China's land area and is one of the world’s largest rivers.
A National Nature Reserve was initially created there because, after the Yangtze River was dammed at Gezhouba in Hubei Province and at the Three Gorges, a large number of migratory fish that would go all the way back to the upper reaches to reproduce faced extinction because hydroelectric power stations blocked their way.
Another reason is that after reservoirs started storing water, the flow pattern, velocity, and temperature of the river were no longer the same. Fish could not adapt to the new environment. There was no other choice than to create a National Nature Reserve in the upper reaches of the Yangtze River.
Unfortunately the Bureau of State Environmental Protection has approved that this National Nature Reserve be moved to somewhere between the north of the Three Gorges Reservoir and Xiangjia Dam, which is the only free section in the upper reaches of the Yangtze River. If this part is not preserved well then hardly any the species of fish found in the river will be able to survive.
If construction plans are followed, reservoirs will be built all along the river, going from Gezhouba Dam up to the Jinsha River and the upper reaches of the Yangtze River. All the natural resources will be used for the creation of hydropower, which is definitely not the correct pattern of development – can such development really be called scientific? This is not to say that we should not develop hydropower, simply that this pattern is not acceptable. Ignoring the protection of nature in this way is like cutting down all the forests that make up the giant panda’s natural habitat to be used in construction projects. How could pandas survive if their homes were destroyed? It is the same with fish. It is essential that we make the general public and society as a whole realise how serious an issue this is!
Wang Yongchen: The Bureau of State Environmental Protection has already passed a proposal to move the National Nature Reserve.
Fan Xiao: Some experts act hypocritically when under pressure and sign off on these proposals.
Wang Yongchen: They are under a great deal of pressure.
Fan Xiao: Government originally stood for the interest of society as a whole, but now the sole aim of some development projects is to make money. Hydropower development projects can now be found everywhere from major tributaries to the very smallest. Many different levels of government have the authority to approve hydropower development projects, which leads to complete chaos.
Zhao Lanjian: Looking at the issue globally, which reservoirs have led to earthquakes?
Fan Xiao: There are a lot of such cases. There have been four or five cases of earthquakes of magnitude 6 or greater in which reservoir construction has been publically acknowledged as the cause. One case that is yet to be completely acknowledged as having been caused by reservoir construction is that of Longyangxia Power Plant in Qinghai, which supposedly led to an earthquake of magnitude 7 in Gonghe, Qinghai in April 1990.
Zhao Lanjian: The cause of this earthquake has not been confirmed?
Fan Xiao: There is still some debate, though geology researchers claim that it was caused by the reservoir. The causes of the other four earthquakes are internationally acknowledged.
Zhao Lanjian: What are the other four cases?
Fan Xiao: An earthquake of magnitude 6.1 in Guangdong in 1962; an earthquake of magnitude 6.5 in India; one of magnitude 6.6 in Zambia, which is recognised as the largest, if those in Longyangxia and Wenchuan are not included. Another was in Greece, of magnitude 6. There have been many more earthquakes below magnitude six that were caused by reservoirs.
We are still studying the causes of the May 12 earthquake, and reservoirs cannot be discarded as a possibility.
Zhao Lanjian: What do you think will happen after all the dams China plans to build are completed?
Fan Xiao: The construction of dams now has a much more negative impact on the environment than deforestation does. Deforestation leads to serious soil erosion, and after the Yangtze River flooded in 1998, China saw the problem and stopped cutting down forests. Whilst one can restore a forest by planting trees, what can be done if a river is dammed? Ought we simply to blow up all the dams? That would not be impossible, but the costs would be far too high. In any case some losses are irreversible, for example those species of fish in the Yangtze River which will become extinct – will they ever reappear? This is very hard to predict, and is no different to the hypothetical extinction of pandas, after which they might never reappear. That is why I have said that building dams represents even greater destruction of the environment than what was done before.
Zhao Lanjian: Are dams truly a green source of energy?
Fan Xiao: No energy source is completely green. Dams are a special case, since they may cause serious geological damage as well as leading to social problems that do not yet have a solution. There are many repercussions, and now more and more dams are being built. Once they start storing water this could lead to a series of geological disasters, starting a period with a particularly high frequency of such disasters. It is imperative that people see the importance of this issue.
Zhao Lanjian: What research topics will you be focusing on in the next few years?
Fan Xiao: I will definitely continue to focus on issues relating to the development of hydropower. Whether on the Jinsha River or on the Dadu River, many reservoirs will come into service either during the five years of the Twelth Five-Year Plan or over the next ten years. It is likely that this will lead to a series of problems, not only geological disasters but also problems with the water supply; that is to say, water shortages. The reason why water shortages may occur is that reservoir storage capacity far exceeds rivers’ annual stream flow and, as a result, rivers might run out of water. This has already happened to the Yellow River. If all the planned reservoirs are built and come into service it will happen to Yangtze River as well. These are not simply my words; this was actually stated by the head of the Yangtze River Protection Agency. Once reservoirs on the upper reaches start storing water, the lower reaches will run out of water and dry up.
Wang Yongchen: What about geological issues?
Fan Xiao: If there is a period with a high frequency of geological disasters, the coming year will be worthy of the most attention. Why? Each year the period from March to May is when geological disasters are most likely to occur. In 2008, around 90 geological disasters were publicly acknowledged. They took place because during this period water levels in reservoirs dropped, triggering around 90 landslides and avalanches in the surrounding areas.
Zhaolan Jian: What standards are still needed for the environmental assessment of dams in China?
Fan Xiao: In the first place our own Environmental Impact Assessment Law should be upheld. Many projects start without passing EIA, even the damming of major rivers. If this can happen, then what use is this law? Internationally, even if a project passes EIA, the general public or an NGO can still take the decision to court if they oppose the project. The final decision is then made by the court, which is a neutral third party.
That day, we interviewed Fan Xiao late into the night. We saw a geologist, a serious scientist, who was passionately concerned about river development. All we can do, however, is write; we can simply report these issues so that more people become aware of them. The Decade River Project can only record what happens, but how we wish could more than that!
What are these damaged rivers trying to tell us?
The following photos were taken by Yang Yong, a geologist, who is also very worried about the development of hydropower.
The landform in a geologically active area
Before Liyuan Power Station was built
Geological structures in the submerged area surrounding Liyuan Power Station
The landform in the valley submerged because of Liyuan Power Station
The current view of Liyuan Power Station, a power station that has not yet passed EIA (photograph by Wang Yongchen)
The sharp turn of the Jinsha River
Debris at a tributary of the Jinsha River
Luding Power Station, which dams the Dadu River
The board reads: We sincerely invite you to work on Ahai Power Plant’s environmental protection program. Your comments and suggestions are valuable to us; we operate are under your oversight.
Tomorrow members of the Decade River Project 2010 team – experts, journalists and volunteers – will share their experience of two weeks spent travelling together. We should listen to what they have to say about the rivers they visited and the people living along the rivers whom they interviewed. For the future of rivers and for our future generations, their ideas matter.
Translator: BAO Lan
Proofreader: Samuel Harding, Angela