China lacking vision

China contradicted the report immediately, but apprehensions persist for valid reasons. China is already diverting water from the Brahmaputra. It has already built a dam on the river, which generates 550 MW of hydel power. There are two more, which together generate another 2500 MW. The report on the thousand km long tunnel, therefore, fits in with China's grand scheme of massive hydel power generation.

China has a notorious record of ignoring the interests of downstream countries when its own interests are concerned. The Mekong river is an example. Over 30 million people in Myanmar, Thailand, Laos, Cambodia, and Vietnam depend on the waters of the river for their livelihood. Its waters irrigate the highly fertile delta region of Vietnam known for its rich biodiversity. Now, China is talking about a 'shared future' common to all these countries. Beijing intends to control the Mekong waters by constructing huge dams to generate hydel power, totally ignoring the disaster this will cause to the other countries. If it can ignore the interests of these countries with such imperial disdain, there is no reason to believe it will show great consideration to the interests of India, with which its rivalry is only growing.

The Brahmaputra originates in Tibet, flows into India through Arunachal Pradesh and from there to Assam and finally to Bangladesh. The hinterland of Assam served by the Brahmaputra covers an area of 56,200 square km. In comparison, the other valley in the state – the Barak Valley – is just 22,250 square km. What will be the impact of diverting the Brahmaputra waters by China on Assam? Ever since the great earthquake in Assam in 1950, the Brahmaputra has been silting heavily, raising the river bed and reducing its water-bearing capacity. This has resulted in widespread floods damaging crops and property becoming an annual phenomenon in Assam, every monsoon. Diversion of water from the upper catchment areas of the river in Tibet will further reduce the river's current velocity, leading to an accelerated rate of siltation. Although there is no reliable data about the quantity of silt lying deposited in the river, according to one source, the Brahmaputra and its tributaries carry around 1.8 billion tonnes of silt per year. This makes de-siltation of the river by dredging an impractical proposition.

De-silting also has a concomitant problem. What do you do with the silt that you have dredged? If the dredger goes on depositing the silt on the river bank as it moves on, next monsoon the silt will be washed back to the river again and things will be back to square one. If the silt (millions of tonnes of it) is to be used for filling low-lying lands, then it has to be transported to distant areas, at a cost which will be prohibitive.

The Brahmaputra is also being threatened by another factor. The primary water source of the river is the Jima Yangzong glacier in Tibet. This glacier is retreating at an alarming pace. If this cannot be stopped then, experts fear, the river may dry up in the next fifty years. But this glacier is not an exception. According to UN climate-change experts, the melting of all the Himalayan glaciers is threatening 1.3 billion people living in downstream countries. Almost a thousand square km area of the Himalayan glaciers has disappeared from the total area of about five thousand square km. The melting process is going on.

Recently, in an interview in Nepal, a Chinese expert, Dr Yang Yong, reportedly stated that if global warming continued at the present rate, all the Himalayan glaciers located at the same height would disappear, within a few decades. As all the rivers originating in the high Himalayas are fed by the glacial waters, their disappearance will have a massive negative impact not only on India but on China itself. Ambitious hydel projects being built by China now will have to be closed down for the dearth of water.

The best thing would be for India and China to take a holistic view of the problem and evolve a mechanism for joint management of rivers originating in the Himalayas and flowing down to India. But, given the present relationship between the two countries, the prospects for such a joint effort are out of the question. As the Himalayan glaciers recede, both countries are inexorably heading towards a disaster.