November 19, 1999

Look across Asia, and you might think that the Big Dam is alive and well. The region is home to much of the world’s dam building, including two of its most ambitious projects: those in India’s Narmada valley and China’s Three Gorges. Though activists have long complained about such giant dams, which flood forests and displace legions of people, Asia’s politicians remain defiant. China is forging ahead with the Three Gorges dam, despite its huge cost: some $30 billion officially, though critics say $75 billion. The Narmada project has already displaced many tens of thousands, and India vows to stay the course.

Officials point to many splendid benefits that are to flow from these projects. The Three Gorges dam is designed both to generate some 20 gigawatts of electricity and to help control the floodwaters of the temperamental Yangzi river. India’s planners promise that the Narmada project will likewise deliver electricity and irrigation. Such ambitions are understandable. Lack of irrigation relegates millions of Indians to subsistence farming. In China, the floods last year destroyed 5m homes. Yet these may well be the last of the really big dams in Asia.

Ironically, one of the arguments now used against big dams is the very mix of motives long used to justify them. That is because these motives have often proved, in practice, to be in conflict with each other. Flood control, for example, requires officials to throw open a dam’s gates; doing so means irrigation water or power production is lost. Releasing water to meet green goals, such as boosting fish populations in the dry season, means lost electricity sales.

The environmental credentials of dams are also under scrutiny. Once, they were embraced by greens as a source of clean and endlessly renewable energy, but no longer. The flooding that accompanies big dams in Asia usually submerges large tropical forests. Recent studies show that, as such vegetation decays, it can release lots of methane, a much more powerful greenhouse gas than carbon dioxide. Also, as Vijay Paranjpye of India’s Pune University notes, dams in the tropics must endure the ravages of monsoons. One common result, he says, is silting-up, which may within a few decades cut the original generating capacity by 70% or even 80%.

Another obstacle is that the flow of aid money is drying up. Since big dams are so controversial, even the World Bank, once the biggest force behind big dams, has grown skittish. The awful mess it got itself into in India explains why. The agency suffered a famous setback earlier this decade when a highly critical outside report led to its departure from the Narmada project. That prompted a broader internal review, which concluded that governments often fail “the acid test” it recommends for dams- “the restoration of incomes and standards of living of project-affected people.”

This points to the thorniest challenge facing big dams: the social cost. In the past, Asia’s heavy-handed governments bothered little about the unfortunates displaced by dams; usually, officials merely made grand promises of cash or land. Though some displaced people do now find better lives, most do not. Some promises are soon forgotten; others, particularly “land for land”, prove impractical in densely populated Asia. Still, the slow but steady advance of democracy in Asia suggests it will be increasingly hard to dismiss lightly the social impacts of dams.

That, anyway, is the hope of the World Commission on Dams (WCD), which is working to build a broad consensus on agreed principles for big dams. Achim Steiner, the secretary-general of the WCD, which was created by governments, development agencies and non-governmental organisations, notes that even Asia’s zealous builders of big dams “are being pulled into global principles by market forces.” This is because they face a squeeze from both private and public investors.

The decline in aid money raises the costs of financing. And the inevitable protests and legal wrangles facing such projects add financial risk, which translates into higher costs. Another blow is the continuing deregulation of the global power industry, which shifts financing to the private sector-and so to low-risk projects with quick returns. That means away from big dams and towards gas-fired plants.

But, if big dams are out, small ones need not be. They can achieve many of the benefits promised by big dams at a fraction of the cost-and with the support of locals. This will grow ever more important, argues Mr Steiner, because “more democratic societies will insist on fuller costing of dams.”

And the locals are growing in importance. In India, for example, pressure from grassroots organisations is forcing the government to scale back its plans for the Narmada valley. The half-finished Sardar Sarovar dam, which is at the heart of the scheme, will probably never be completed. Smitu Kothari of Lokayan, a social-policy think-tank in Delhi, insists that, “of the 3,300-odd dam projects that were originally envisioned in the Narmada valley, there will be a 70% reduction.” The number of dams is sure to be cut and the heights of those remaining reduced; many will also be redesigned to reduce their social and environmental impact.

Even in China, the big-dam juggernaut is not quite as formidable as it once seemed. Doris Shen of the International Rivers Network, an American non-governmental group, points to the admission a few weeks ago by Chinese officials that the $3.4 billion Ertan dam, the biggest yet completed in China, is having difficulties selling its electricity, which is significantly more expensive than that from smaller power stations. As the true costs of the Three Gorges dam soar toward $75 billion, she reckons, only hubris or kickbacks will save the project.