ON 12 May 2008 an earthquake of magnitude 7.9 hit the eastern region of in China. It killed 70,000 people, made 5 million people homeless, blocked rivers, and put more than 300 dams at risk, threatening yet more death and damage from flooding.
The quake was felt as far away as India, Taiwan and Mongolia. It was caused by movement of the fault that lies between the high plateau of Tibet and the crust beneath the Sichuan basin and south-east China. Seismology tells us that earthquakes occur when the tectonic stresses that accumulate along faults reach a critical point and a sudden release occurs. There can always be speculation about what triggers an individual earthquake, however. Natural inevitability is one thing, but what if the trigger is pulled by mankind?
That question is now being asked about the Sichuan earthquake. A suggestion recently made by seismologists is that Sichuan鈥檚 newest dam, completed in 2006, might be to blame. This is the Zipingku dam on the Min river near Dujiangyan. The increasing load of water in the reservoir behind the dam might have been the final straw that provoked the catastrophic release of the Longmenshan fault鈥檚 local stresses. If so, the seismologists who warned of an earthquake risk before the dam was built have been vindicated.
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Sichuan is a land of many dams, most of them built in recent decades. The mightiest of them is the Three Gorges dam on the Yangtze river. It is the world鈥檚 biggest dam, lying a mere 550 kilometres east of the Sichuan earthquake鈥檚 epicentre. That fact had engineers rushing to check the safety of the Three Gorges dam in the quake鈥檚 aftermath. The reverse procedure 鈥� checking the earthquake and other environmental implications for the region before this or any other large dams, such as Zipingku, were built 鈥� did not have nearly the same urgency for a country involved in a headlong and ruthless rush for economic development.
As it happens, one of the most tragic aspects of the Sichuan quake was the many deaths of schoolchildren, whose cheaply and hastily built schools collapsed on them. The poor construction of schools and the gung-ho production of dozens of dams in a tectonically active region are of a piece: they are both evidence of carelessness, skewed values and folly.
鈥淐hina鈥檚 construction of dozens of dams in a tectonically active region is evidence of skewed values鈥�
There is a striking contrast between debate about science and technology in China and the west, as the following example shows. This month the journal to study how migration patterns influence its spread. The reports say this has caused 鈥渃onsternation鈥� among poultry farmers and bird-watchers. My first thought on seeing this news was that consternation is not enough, because of the possible harm to human populations in Europe鈥檚 crowded hectares, given that some strains of avian flu have a disastrous talent for leaping species. How, I wondered, could such an experiment be allowed in the Netherlands? In China, plans to build a dam go unchallenged because the country runs along dictatorial lines. But one of the stocks-in-trade of the Dutch is common sense, wedded to solid ideas of due process and due diligence.
It turned out that the avian flu strain in question is not dangerous to humans and is already widespread among European birds. The experiment was vetted and approved. I had leapt to the wrong conclusion and, along with the twitchers and poultry-farmers, was immediately ready to protest. Note the difference: we here can complain about schemes, even when doing so is based on misapprehensions. In China, the first thing that penetrated the authorities鈥� deafness was the rumble of an earthquake.
