The reason for renewing this interest will be evident in the next post when another prediction will be made.
Dams that burst the earth by John Goss
No Richter Scale can measure the grief of families affected by the earthquake epicentred near the town of Bhuj in January this year. While yet another catastrophe claimed the lives of many thousands the cost of regeneration, rehabilitation and relief is going to run into millions and take many years. A billion pounds might turn out to be a conservative estimate. Some of this will be paid for by international aid of which Tony Blair has pledged ten million pounds. Only the most heartless of people would deny aid to a grief-stricken earthquake region. Yet this earthquake may have been avoided. Or at least the magnitude of it diminished. Paying for avoidable catastrophes is bad economics.
It has long been known that dams can cause earthquakes. As the death-toll rises daily questions need to be asked why permission to construct large-dams like the Sardar Sarovar dam on the Narmada river was ever granted, especially since the World Bank ceased to fund the project in 1993 due to concerns that it was neither economically nor ecologically viable. More important in their eyes was concern that the needs of the indigenous population would not be served. For similar reasons Japan pulled funds in 1990. Too late now, but their concerns were well-founded. Their findings were ignored by the Indian government.
More than thirty years ago Gordon Rattray Taylor in the Doomsday Book warned "The prospect now looms of man being able to cause earthquakes at will, or, what is more probable, of doing so by mistake." He was talking about shifts and slippages in the crust of the earth caused by the sheer weight of water in large-scale dams. The link between earthquakes and dams was first made in 1945 by D. S. Gardner. He showed that Lake Mead, an artificial reservoir created by the building of the Boulder (now Hoover) dam in Colorado, was responsible for resultant earthquakes in that region. Lake Mead began to fill in 1935. As the height and weight of water in the dam increased so did the magnitude of the earthquakes. When the lake was full a pressure of 25 billion tons of water brought a quake with a Richter reading of 5. Once this link was made subsequent dams and subsequent earthquakes confirmed the findings until today no scientist who valued his or her reputation would deny the connection.
Predicting whether or where a resultant earthquake is likely to occur when dams are filled is an imprecise science, so imprecise most earthquake predictors ignore prediction altogether. The reason is some big dams do not appear to cause earthquakes or tremors at all. While others clearly do. Obviously building a dam in an area prone to earthquakes is asking for trouble. Yet this happens. Depending on viewpoint resultant earthquakes can either be blamed on the dam or an inescapable truth that there are always earthquakes in that region. All dams today have seismic monitoring instruments built into their walls, a clear indication that there is an accepted connection between the two events — filling dams and earthquakes.
More than two hundred kilometres from the epicentre of the Bhuj earthquake a dam is being filled. In June 1999 the water at the dam on the Narmada river in Gujurat rose from 80.3 metres to 88 metres in three months following a supreme court decision permitting this increase. This overturned a ruling made four years earlier which put a stay on further development. India should have learnt its lesson from history. Sadly, it did not.
On December 10, 1967 following a series of tremors after the construction of the Koyna Dam an earthquake with a Richter reading of 6.4 took place. One hundred and seventy seven people in the town of Koynanagar, 150 kilometres south east of Bombay, were killed while damage and disruption was widespread throughout India. There had previously been no earthquakes in this region.
Like the ground itself the subtle emphasis of the earthquake argument had moved long before the Sardar Sarovar project was underway. Concentration shifted to whether the dam would survive the impact of an earthquake. Nobody with influence questioned whether it would actually cause one anymore.
Early in 1991 there was outcry concerning the $2 billion Tehri Dam Project at the foot of the Himalayas. This had financial support from "green" activist Mikhail Gorbachev’s Soviet government. Scientists, however, claimed the dam was technically unsafe. Here again a case was put for the inhabitants of the region. Much concern was shown for the likely earthquake impact on the dam rather than the dam's impact on the earth. It was being constructed in a known seismically active region. The main fears centred on what would happen downstream if the dam burst — not an unreasonable concern. According to the New Scientist it was only designed to withstand a quake of 7.2 magnitude.
October of that year saw the worst earthquake Delhi could remember. It killed more than 500 people, injured more than 3000 others and left thousands homeless. The main quake measured 6.1 on the Richter scale. Its epicentre was close to Tehri.
Construction of the Sardar Sarovar dam, the biggest of 30 planned large dams, was not without its opposition though scant emphasis was placed on the possibility of earthquakes. What was paramount in the minds of the villagers immediately affected, and hardly surprising, was where they would live and how they would make a living. Many of those who were moved out returned to the area they knew. The river was their life. The villagers' case was put in an impassioned letter of protest to the Indian government from Bava Mahalia of Jalsindhi. “You," he said, "and all those who live in cities, think that we who live in the hills are poor and backward, like apes. 'Go to the plains of Gujarat. Your conditions will improve. You will develop' — this is what you advise us... If it is true that our situation will improve in Gujarat, then why aren't all of us ready to go there?” He was ignored, like others before him.
Though not a supporter of the dam some of the best arguments in favour of it were summarised by Geoff Holland, of the Institute for Global Futures Research (IGFR) at Earlsville, Australia. Those favouring its construction claimed it would bring benefits in the form of improved conditions, the gift of farmland, roads, schools, electricity and clean water. Was that what the villagers needed? It was not what many wanted. Of those resettled, according anti-dam activist Shripad Dharmadhikary, more than 500 families had returned to the Narmada Valley because of discontent.
On another level a battle-royal raged between B.G. Verghese, a columnist from the Centre for Policy Research, in favour of the dam, and Arundhati Roy, Booker prize-winning novelist, opposed to it. Feathers flew.
Verghese's cause had the weight of big money, big government, government organisations, commerce and industry behind it. Arundhati Roy supported a cause which had little financial help, though she gave all her Booker prize money, $34,000, towards the campaign. Further support came from a few high-profile personalities, who like herself helped to put the case, and the Narmada Bachao Andolan (NBA), a human rights group opposed to the dam. Arundhati wrote that big dams are to a nation's development what nuclear arms are to its Military Arsenal — weapons of mass destruction. In response to her essay “The Greater Common Good” Verghese taunted Arundhati claiming the poetry of her language veiled inaccurate arguments.
“The SSP (Sardar Sarovar Project) displaced are a charge on the project with a generous plan, budget and organisation for their rehabilitation.” he said implying that Arundhati was a scaremongering neo-Luddite. Since many of the villagers did not want this package she came swiftly back at Verghese with another essay, equally prosaic, equally as forceful in its propositions and equally unwavering as the first.
“Almost everyone who wants to rubbish my argument begins by paying me extravagant, back-handed compliments about my ‘poetic writing’. Almost as though poetry by definition is imprecise, unsubstantiated mush. Not something that Real Men who build Big Dams dabble in.” She criticised the project for its effects on the environment as well as on villagers. She further criticised it on grounds of cost.
Not to be outdone Verghese countered with a statement that costs "have little meaning unless weighed against corresponding benefits." Benefits he argued would "be far greater on any count." He might be prepared now to stand back and reassess this claim in the aftermath of an earthquake which he failed to foresee as a possibility.
Before this devastating catastrophe Geoff Holland suggested a few alternatives. He predicted that greater benefits would accrue from the Narmada river if multiple small dams were constructed to provide "irrigation, electricity generation, and flood control without ... soil erosion, deforestation, desertification, and displacement."
Though an imprecise science geologists and earthquake monitors have a largely accepted theory that expansions and contractions of land within known faults are the main causal factor of large earthquakes. When the tectonic plate gives it gives at a weak, and normally low-lying, point. A major fault runs along the foot of the Himalayas and it is concluded that the expansion northwards of land south of this fault was responsible for the latest earthquake.
In the absence of any real evidence one possibility, of which there appears to be no research, is that large rivers act as buffers for land expansion. Rivers are low-lying and thus potentially weaker than the surrounding land. That being so their function would be similar to gaps in large bridges which allow sections to expand and contract. If the depth of the river is suddenly increased the give in the buffer is diminished thus constricting expansion.
Tragedies happen everywhere. With some, for example a train derailment, there are enquiries. Earthquakes are all too often glibly dismissed as acts of God, even when they can happen to be acts of man. There is no accountability. Hopefully one day governments granting aid will enquire where else in the world big dams are being built and put a stop to them. There are alternatives.
Robert Goodland, an expert on big dams and representative of the World Bank, is concerned that when loan organisations withdraw funding for non-viable projects there are no follow-up procedures to monitor what recipients do next. He and others like him question whether the World Bank should "retain responsibility for a project even after the loan has been disbursed or cancelled . . . until decommisioning, rehabilitation and restoration." The Indian government took it upon itself to increase the height of the Sardar Sarovar dam regardless of advice from the loan organization.
One Wednesday in July 1999 a seven year old girl, Lata Vasave, from the tribal village of Domkhedi, became trapped in the silt of Narmada Valley. She drowned. She had gone to carry water from the edge of the Sardar Sarovar reservoir. Fetching water was something her ancestors had done for centuries. Mud deposits washed down behind the dam were ten feet deep and had already claimed the lives of cattle trying to reach the water’s edge. Traditionally villagers have used the Narmada river as their source of domestic water as well as for bathing and fishing. That day in 1999 a village mourned the loss of a little girl. Today many of the same villagers relocated in towns and cities struck by the earthquake, and others like them, are engulfed in immeasurable grief — or dead themselves.
John Goss is writing the biography of eighteenth century English novelist Robert Bage (1730-1801). Eighteen months before it happened he warned of the possibility of an earthquake in the Gujurat region.