The building of large dams has increasingly run into grassroots opposition in established democracies but gained momentum in autocratic states, which often tout their benefits for combating droughts and water shortages. But, as the Mekong Basin illustrates, giant upstream dams can contribute to river depletion and intensify parched conditions. The spate of dam building in Asian autocracies is exacerbating already-fraught water security disputes.
India, for its part, demonstrates that dams and democracy normally don’t go well together. Whereas China continues to build giant dams, describing them as symbols of its engineering prowess, the public pressures generated by India’s democracy act as a brake on ambitious water projects that displace many people or flood vast areas. While India’s river-linking plan remains in the realm of fantasy, a similar programme in China has been transferring water domestically through the central and eastern routes.
In fact, given the power of non-governmental organisations in India, it has become increasingly difficult to build large dams, blighting the promise of hydropower. Proof of this was the central government’s 2010 decision to abandon three dam projects on the Bhagirathi River, a Ganges tributary, including one that was already half-built, with authorities having spent $139 million on construction work and ordered equipment worth $288 million.
Cost and time overruns are common problems in every dam project in India. For example, the cornerstone of the Narmada Dam — 15½ times smaller than China’s Three Gorges Dam, built ahead of schedule — was laid in 1961. More than 56 years later, Prime Minister Narendra Modi inaugurated the dam. The Narmada project, however, is still not fully complete.
Last week’s debut of the 1,285-megawatt Xayaburi Dam in Laos illustrates how autocracies defy protests and concerns to complete projects. The Xayaburi — the first of at least nine Mekong dam projects in Laos — was commissioned despite concerns that it could worsen the drought in the downstream basin in Cambodia and Vietnam.
No nation, however, can match China’s dam-building frenzy. It is increasingly damming international rivers. Take the Mekong. Just before that river crosses from the Tibetan Plateau into Southeast Asia, China has erected a cascade of mega dams. Its 11 Mekong dams have a capacity to generate more than 21,300 megawatts of electricity — greater than the installed hydropower capacity of the downriver countries combined. It is working on at least eight more giant dams on the Mekong.
Ever since the cascade of Chinese dams came up on the Mekong, droughts have become more frequent and intense in the downriver countries. The Mekong, which is normally at least three metres high at this time of the year, is today running at a record low level, with its flow reduced to a trickle in some stretches. This has resulted in seawater intrusion into the Mekong Delta in southern Vietnam, with rice farmers there forced to switch to shrimp farming or growing reeds.
China has promised to release more dam water for drought-stricken countries. The offer, however, highlights the newfound reliance of downriver countries on Chinese goodwill.
By diverting river waters to its mega dams, China has emerged as Asia’s upstream water controller, arming it with powerful leverage.
The downriver countries have also been saddled with long-term environmental costs. For example, Asian rivers’ monsoon season flooding cycle helps to refertilise farmland naturally by spreading nutrient-rich sediment, which rivers bring from the mountain ranges. The flooding cycle also opens giant fish nurseries. China’s dams, however, have disrupted the Mekong’s annual flooding cycle and impeded the flow of sediment.
The Mekong Delta also exemplifies how heavy upstream damming, by reducing a river’s discharge of freshwater and sediment into the sea, causes a delta to retreat. Indeed, according to a Mekong River Commission study, the upstream dams’ cumulative effect would likely be the extinction of most migratory fish species in the basin. What is happening to the Mekong today could happen tomorrow to the Brahmaputra and other Tibet-originating rivers that are the target of China’s dam builders.
Simply put, the proliferation of upstream dams is beginning to impose costs across much of Asia. Dams are also set to exacerbate water-sharing disputes, which have already become common between Asian nations and provinces. Add to the picture the security dynamic: For example, the Mekong, like the South China Sea, is emerging as a new flashpoint, with US secretary of state Mike Pompeo slamming China’s dam frenzy for reducing the river’s flow to a record low.
Dams help generate electricity and store water for the dry season. But heavy upstream damming, by irreparably damaging a river system and wreaking broader environmental havoc, eventually leaves only losers. To avert a parched future, defiant unilateralism must give way to basin-wide institutionalised collaboration, centred on a balance between each county’s rights and obligations.
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