Special issue with the Sunday Magazine
From the publishers of THE HINDU
RIVERS: JULY 01, 2001
Cutting off a lifeline
The author teaches sociology at Delhi University. She is the author of In the Belly of the River: Tribal Conflicts Over Development in the Narmada Valley.
If you hold out your hand, palm up and slightly cupped, and examine the tracery of lines running across, you will find that the deepest is the one arcing around the base of the thumb, the one that palmists call the lifeline. They say the lifeline foretells fate, the breaks in its flow mark moments of crisis and danger.
Rivers are lifelines too. To their fate are bound the destinies of those who live in and around them. And the greatest crises confronting them are the breaks - large dams - that disrupt their flow. Each lifeline is unique and dynamic. That is why we can never step into the same river twice. We barely grasp the complex play between water, land and living beings. Yet we proceed with careless arrogance, an army of plumbers, treating rivers like tanks and taps, to be turned on and off at will. How are dams disastrous for rivers? How do they change the fluid ecology of a landscape and its biological elements? Let's begin by looking at rivers - what they are and what they do.
As it flows from the highlands through the plains to the sea, a river carries not just water but silt, a nutrient-laden soup that spreads fertility on the floodplains and nourishes the teeming life of the estuaries where sweet water meets the salt of the sea. Farming in the floodplains, using centuries of silt deposits, has been richly productive, generating the economic surplus that supported complex societies. There is truth in the clich‚ that river valleys have been "cradles of civilisation". Yet rivers inspire creativity even under materially sparse conditions. In the rugged reaches of the Narmada, adivasis sing the gayana, a creation myth celebrating the life-giving power of Narmada, a generous, free-spirited girl wandering to meet her lover, the sea. The Ganga and other Indian rivers delineate a sacred geography too, each teertha or ford bridging this world and the next. This effortless marriage of nature and culture, the mundane and the sublime, that rivers embody, seems eternal. But this sense of timelessness is a fiction.
As Patrick McCully says in his powerful book, Silenced Rivers, nothing alters a river as totally as a dam. The essence of a river is that it flows, the essence of a reservoir, that it is still. Still waters kill off a whole range of species adapted to a flowing environment. According to McCully, dams are the main reason why fully one-fifth of the world's freshwater fish are now either endangered or extinct. Crocodiles and turtles, amphibians and molluscs, insects and waterfowl - we know little about their fate once a river is dammed. This ecological diversity is destroyed even before we have fathomed its mysteries.
Not only does a dam alter a river forever, its reservoir submerges vast areas, drowning forests, farms, villages and towns. Rowing across the Bargi reservoir on the Narmada, displaced villagers point downward into the water - this is where our weekly market was, that my wife's natal home. Homes, lands and the ways of life spawned by rivers, are swallowed up by dams. The stilled waters of a dam seize one of the oldest gifts that a river keeps bestowing - the regular replenishing of the floodplains' fertility. Silt is trapped at the bottom of the reservoir, a dead loss, and agricultural lands are impoverished.
When a large dam diverts water into irrigation canals, it reduces downstream flows to a trickle. This plays ecological havoc with aquatic life below the dam. River diversion caused the Aral Sea (a freshwater lake) in central Asia to shrink to half its size and become so saline that a flourishing fishing industry was devastated. The Sardar Sarovar dam will destroy the rich Narmada Hilsa fishery, just as North American dams have already wiped out vast salmon populations by blocking their spawning migration. Deprived of sediment, the life of an estuary dwindles.
Most of the world's economically valuable fish species spend part of their life-cycle in estuarine habitats; less silt means less food for fish and often also a loss of livelihood for fisher-people. The silt brought by the Nile to its mouth once would cause huge plankton blooms that were grazed by great shoals of sardines. After the closing of the Aswan dam, fish and shrimp catches plummeted. We do not often realise that rivers support not just biological life, but the very land itself. Without regular silt deposits to stabilise its banks, a river cuts wider and deeper, eating into the land. Robbed of sediment, the rivers cannot hold the shore against the encroaching sea.
Damming rivers has enormous consequences for the life of forests, plains and the seashore. Planners and engineers usually set aside these ecological hazards by invoking the imperative of "economic growth". The enormous long-term costs of such growth are always under-estimated, while their benefits rarely reach the poorest. We have to look beyond dams at other strategies, many of them now tried and tested, to irrigate arid areas. Rivers are so easily abused: pollution chokes them, embankments divorce them from the land. But while rivers can be cleaned and embankments dismantled, no easy tasks but still possible, a dam destroys forever. Surely the fate of our rivers, our lifelines, cannot be sealed with such dreadful finality?
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