Tag Archives: Mekong river

Choking the Water: Dams, Dams and More Dams

Since Tibet is part of China, Chinese engineers have been making the most of that potential. They have built big dams not only on rivers like the Yellow and the Yangzi, which flow across China to the Pacific, but also on others, like the Brahmaputra and the Mekong, which pass through several more countries on their way to the sea.

China has every right to do so. Countries lucky enough to control the sources of big rivers often make use of the water for hydropower or irrigation before it sloshes away across a border. But If the countries nearest the source of water, like China,  suck up too much of the flow, or even simply stop silt flowing down or fish swimming up by building dams, the consequences in the lower reaches of the river can be grim: parched crops, collapsed fisheries, salty farmland.

Tension and recrimination have been the order of the day for China and its neighbours… In part, this is because a river like the Mekong does not contain enough water to go round. China has already built 11 dams across the main river (never mind its tributaries) and has plans for eight more; the downstream states have built two and are contemplating seven more. Last year, during a drought, the river ran so low that Cambodia had to turn off a big hydropower plant. Even when rainfall is normal, the altered flow and diminished siltation are causing saltwater to intrude into the Mekong delta, which is the breadbasket of Vietnam, and depleting the fish stocks that provide the only protein for millions of poor Cambodians.

China has long resisted any formal commitment to curb its construction of dams or to guarantee downstream countries a minimum allocation of water. It will not even join the Mekong River Commission, a body intended to help riparian countries resolve water-sharing disputes…

China has not signed any agreements about managing the Mekong with the other countries it flows through, so is not obliged to share a particular amount of water with them, nor even provide data on the flow or any warning about the operations of its dams. It does provide the Mekong River Commission with a trickle of information about water levels and planned releases from dams, which helps with flood-control lower down the river

Excerps from Water Torture: Hydropower in Asia, Economist, May 16, 2020; Torrent to Tickle: the Mekong, Economist, May 16, 2020

Water Shortage Mekong Basin

2016: Drought is plaguing much of mainland South-East Asia, including Myanmar, Laos and Cambodia. Thailand’s shortages are the worst for two decades,  Vietnam has been hit as hard as any. The Mekong basin is home to one-fifth of the population. It produces about half of the country’s rice. The government says the amount available for export in the three months to June will be 11% less than originally forecast. Drought in the country’s Central Highlands has affected a third of coffee plantations there and now endangers the region’s supply of drinking water. These woes are weighing on the economy. Growth in the first quarter slowed by half a percent year-on-year to 5.5%.

The immediate cause is El Niño…People living near the Mekong say there is another problem: hydroelectric dams built in China near the head of the river that are holding up its flow. Since March China has loosened some of the dam gates, ostensibly as a favour to its neighbours. But locals say the effect on water levels has been measly. The episode has only heightened fears that China (with which Vietnam has an enormous trade deficit and an intense territorial dispute) can use water flow to hold the country to ransom.

The dams are certainly stripping the Mekong of essential sediment. But many of Vietnam’s water woes are self-inflicted. In the delta, for example, a booming population has built more than 1m wells since the 1960s. These have made saline contamination worse, and are also causing subsidence. In 2014 an American study found that the delta, which mostly lies less than two metres above sea level, could be nearly a metre lower by 2050.

A related problem is the ruling Communist Party’s obsession with maximising rice production. Straining to hit absurd targets—inspired by memories of post-war food shortages—the government has pushed delta farmers to produce three rice crops per year.

This policy has caused the poisoning of paddies with pesticides and has discouraged farming of more profitable, less thirsty crops. It has also prompted the building of a massive network of dykes, canals and sluice gates, which spread pollution from fertilisers and pesticides and restrict the flow of sediment. Koos Neefjes, a climate-change expert in Hanoi, the capital, reckons all this infrastructure has done more to harm the delta than China’s dams.

Fixing this will mean taking on powerful state-owned rice traders and exporters, who benefit from intensive production.

Excerpts Vietnam’s drying delta: Salt of the earth, Economist, Apr. 30, 2016, at 37

Divide and Conquer: the Mekong River

Laos has given the go-ahead to build a massive dam on the lower Mekong river, despite opposition from neighbouring countries and environmentalists.  Landlocked Laos is one of South-east Asia’s poorest countries and its strategy for development is based on generating electricity from its rivers and selling the power to its neighbours, says the BBC’s Jonah Fisher in Bangkok.  Xayaburi is being built by a Thai company with Thai money – and almost all of the electricity has been pre-sold to Thailand, BBC says.

Countries such as Cambodia and Vietnam point to a report last year that said the project should be delayed while more research was done on the dam’s environmental impact. Up to now, Laos had promised not to press ahead while those concerns remained…

Laos has followed the letter, if not the spirit, of the 1995 Mekong Agreement. Under its terms, the countries that share the Mekong agree to prior consultations on the possible cross-border impact of any development on the river before deciding to proceed. Laos believes it has just done that.  Cambodia and Vietnam expressed concerns about the dam’s impact on fish migration and the flow of sediment downstream. So the Laos authorities brought in their own contractors and now say the problems have been solved.  Critics of the dam say many of the modifications to it are untested and the decision to proceed amounts to a huge experiment on one of the world’s great rivers.

Four dams already exist in the narrow gorges of the Upper Mekong in China but until now there have been none on the slower-moving lower reaches of the river..Laos deputy energy minister Viraphonh Virawong said work on the Xayaburi dam itself would begin this week, and hoped it would be the first of many….

Excerpt, Laos approves Xayaburi ‘mega’ dam on Mekong, BBC, Nov. 5, 2012