COOPERATION BETWEEN CHINA, NEPAL AND INDIA
Brahmaputra Diversion Through Nepal
By Dr. AB Thapa
The supply of water is gradually dwindling in the Ganga basin of the South Asia because of ever growing demand for water . It was one of the main causes of sour relationship between India and Bangladesh in the past. The recent Farakka agreement between India and Bangladesh on Ganga water sharing has helped to a great extent to resolve this problem. However, both the countries accept the fact that sooner or later the present dry season flow of the Ganga must be augmented. There are two proposals. (1) India proposes to divert the Brahmaputra at Jogighopa in Assam through Bangladesh into Ganga near Farakka. (2) Bangladesh proposes to build storage reservoirs in the Ganga basin itself to augment the dry season flow. Both the countries are sticking to their own proposal. A compromise appears to be very remote However, there could be other alternatives also. One of such possible options could be based on ideas floated by scientists at the Harvard, USA. It is the diversion of Brahmaputra through Nepal into the Ganga.
Scientists at Harvard
In the book " Eastern Water Study" the scientists at Harvard ,USA have stressed the need of creative thinking about assessing inter-basin transfer of water options including trans-Himalayan prospects using the Gandak or Kosi for diversions from Tsangpo (Brahmaputra). Such diversion could be very effective for mitigating the problems of growing shortages of dry season flow of the Ganga river and also for the generation of cheap electricity.
WECS’s Concept
The diversion of the Brahmaputra river into the Arun river from a suitable place not too far away from the Sigatse ( in China) could be one of the options. The Brahmaputra is a very big river and thus its valley must be deep compared to Arun valley. It implies that a long tunnel would be required to effect such diversion. This tunnel length could be considerably reduced by adopting the following two measures. (1):Provision of a high dam across the Brahmaputra river for elevating the water level and also for storage. (2) Provision of pumping station if further elevation of water level is desirable. It could be single or multistage pumping for delivery of water into the Arun system.
The Brahmaputra River
The source of the mighty Brahmaputra river known as Tsangpo in China lies in the Cheme-Yungdong Glacier near the Lake Manasarobar in Tibet. This river flows for 2900 kms from its source to its confluence with the Ganga in Bangladesh. This river enters Bangladesh as the Jamuna . The mingled water of the Ganga and the Jamuna ( Brahmaputra) empties into the Bay of Bengal. It might surprise us to learn that not until early in the last century it was certain that the Tsangpo and the Brahmaputra were one.
Compatibility of the Project
Due to vast difference in climatic conditions of the tropical Indian subcontinent and alpine type environment of the Tibetan plateau , the adverse effect of the Brahmaputra diversion on Tibet might not be too significant. The diversion of the Brahmaputra is required mainly in two seasons . These two seasons are the spring and winter. In rainy season of summer the diversion is not necessary because there is always plentiful of water in the Ganga itself.
In Brahmaputra region of the Tibet like in all other similar regions of the north the spring season is the time of plentiful water. The Brahmaputra river must be in high floods in spring seasons when the snow all over Tibet lying below the perpetual snow line completely melts. Such abundant flood water could be diverted into the Ganga. Quite the opposite, the spring season is a period when there is acute shortage of water in the Ganga.
The diametrically opposite spring season hydrological characteristics of the upper reach Brahmaputra and the Ganga make the trans-Himalayan diversion attractive. The prospect of diversion of the Brahmaputra into the Ganga in autumn and winter is also not bad.
Tibet needs water in limited quantity for irrigation mostly in summer season when the ambient temperature is sufficiently high to support the growth of agricultural crops. After a very short warm period of summer months the temperature again starts to lower down. Towards the middle of autumn before the temperature plunges down to a level close to freezing point not only the harvesting but often even the sowing works for the next season's crops should be completed. This signifies that during the autumn the use of Brahmaputra water in Tibet would be only limited. Thus a good proportion of the autumn flow of the Brahmaputra could also be diverted without adverse effect on the Tibetan agriculture.
In winter every thing on the surface is frozen in Tibet including the top layer of water in the river. Beneath the ice the water of the Brahmaputra flows even in the coldest day of a year. There are hardly any chances of utilization of such Brahmaputra water in Tibet in appreciable quantity. A good proportion of the winter flow of the Brahmaputra could be diverted to augment the Ganga flow.
Abundant Electricity Generation
The diversion of the Brahmaputra into the Ganga would allow to generate cheap electricity in big quantity. There is a very big drop in elevation between the Tibetan plateau and the Ganga plain . Such drop is about 5 kilometers. This big drop in elevation could be used for power generation.
Cooperation Between China, Nepal and India
Finding new ways to exploit the vast water resources that might indefinitely remain idle in the remote areas of the Himalayan region could be a challenge before the scientists and technicians in this new century. The diversion of the Brahmaputra through Nepal into the Ganga could be one of such engineering problems.
About two decades ago RONAST had carried out extensive exercise to set up a Regional Center on snow and ice in Nepal. The objective of the proposed CENTER was to develop cooperation among the countries of the Himalayan region for glaciological research in the mountain range of the Himalaya. The CENTER was expected to promote sustainable economic and social development studies. . As such, it would have consisted largely of application oriented research with both scientifically and socially valid objectives. RONAST, to take this idea a step further, even established relationship with Italian National Research Center (CNR) to carry out jointly Himalayan studies. A big research center equipped with modern facilities has already been set up near the base camp of the Mount Everest at Lobouche.
In future China, Nepal and India could work together to set up a Regional Center on snow and ice. Such centre would have been the most appropriate institution to help the Brahmaputra diversion or similar other studies.
(Dr. Thapa writes on water resources)
