In 1896, the "Harmon Doctrine" was propounded by the US Attorney General Judson Harmon, claiming that Mexico was not entitled to the water from an international river, the Rio Grande.

The doctrine emphasised territorial sovereignty over an international river. It means that, within its territory, a state can do whatever it wishes with the water of an international river, and does not need to bother about the consequences of its withdrawal on a lower riparian nation.

India argued in favour of the Harmon Doctrine in the mid-70s with Bangladesh (I was Director General of South Asia), though the US itself had discarded and discredited it in 1906 when it concluded a treaty with Mexico relating to sharing of water of the Rio Grande.

When India argued the relevance of the Harmon Doctrine in the '70s, Bangladesh counter-argued that the "Helsinki Principles", which would entitle a co-riparian of a reasonable and equitable share of water of an international/common river or drainage basin, had replaced it in 1966.

Use of river water
The use of river water is of two types -- non-consumptive and consumptive. Navigation is a non-consumptive use of water because river water is not depleted or reduced through navigation. Consumptive use of water consists of withdrawing water for agricultural and other purposes. Consumptive use always reduces the water in rivers.

A river knows no political boundaries between countries. It flows as an indivisible unit, and if it is interfered with at the upper stream, the lower riparian country will be affected. That is why international law recognizes the right of each riparian country to enjoy all the advantages deriving from river waters for the welfare and economic prosperity of its people.

At least 56 rivers flow from India into Bangladesh. The largest of them, the Ganges, the Brahmaputra and the Meghna (GBM), flow through Bangladesh until they meet the Bay of Bengal, creating one of the biggest deltas in the world. It is estimated that 25,000 square miles within Bangladesh can be designated as a delta, an area equal to Belgium and the Netherlands together.

Bangladesh is a land of rivers, and swimming has been the birth-right of all Bangladeshi children. Rivers have been the lifeline of the people of Bangladesh, although in the monsoon season they often cause floods. Without monsoon rain and the rivers, Bangladesh's environment, and its cultural tradition, music, and folk tales based on rivers, will die.

Agriculture is the backbone of the country, and 76% of the people live in villages. Water plays the most vital role in the country's economy. 85% percent of the water comes from the Ganges and the Brahmaputra during the dry season (November to May).

Millions of people are directly or indirectly dependent on river water for their livelihood. Water is vital for agriculture, fishery, and the flora and fauna, and constitutes an indivisible part of people's lives.

Depletion of water in rivers puts Bangladesh in a very critical situation, especially in navigation, agriculture, and way of life. Farmers, fishermen, and the forests, are all adversely affected by depletion of water in rivers.

Water dispute and Bangladesh
The unilateral withdrawal of water from the upper reaches by India has been a concern for Bangladesh. If India withdraws water heavily from common or international rivers, such as the Ganges and the Brahmaputra, there will be less available in Bangladesh. This is obvious.

The water dispute with India has been going on since the birth of Bangladesh. It started with India's ill-conceived Farakka Barrage on the Ganges (11 miles from Bangladesh's border), for diverting water from the Hoogly river for flushing silt, not for agriculture.

India's pre-occupation has been how to divert water from common rivers without sharing information, or consulting, with Bangladesh. For example, information regarding the storage of water of the Barak river, by building the 1,500 MW Tipaimukh hydroelectric dam, has yet to be shared with Bangladesh.

India has embarked on constructing dams on, and diverting water from, many common rivers, such as the Teesta, the Gumti, and the Khowai, without any agreement with Bangladesh. India had reportedly blocked-of streams (such as Muhuri, Chagalnaiya, Fulchari, Kachua and many others) flowing into Bangladesh from Tripura. As a result, as of 1979, eight chars (islets) were detected in the tributaries of Muhuri and Kahua, and they have blocked water flow in Bangladesh.

Since these rivers are in India, it did not care to discuss, consult, or come to an agreement with Bangladesh on the blockage or diversion or consumptive use of the water, although a Joint River Commission had been formed in 1972.

China's proposed diversion of water
According to a report by an Indian writer, China is attempting to dam or redirect the southward flow of water from the Tibetan plateau, the starting point of many rivers, such as the Indus, the Mekong, the Yangtze, the Yellow, the Salween, the Brahmaputra, the Karnali and the Sutlej.

According to the same writer, China's intensive farming needs water, and it is increasingly turning its attention to the water reserves of the Tibetan plateau. China is presently toying with massive inter-basin and inter-river water transfer projects.

Furthermore, several Chinese projects in west-central Tibet have a bearing on river-water flow into India, but China refuses to share information with India. The same tactics India adopted with Bangladesh are now likely to bite India.

The writer also pointed out two Chinese projects that might affect India adversely. One is the proposed Great South-North Water Transfer project for diverting Tibetan water, and the first phase calls for building 300-kilometres of tunnels and channels to draw water from the Jingsha, the Yalong and the Dadu rivers on the eastern rim of the Tibetan plateau.

The second phase of the project is more damaging, because it proposes to re-route the Brahmaputra river northward. In fact, the writer points out that China has identified the bend where the Brahmaputra enters India.

India does not seem to have considered that the Chinese water experts and hydrologists may have acquired the technology by which the Tibetan plateau waters could be re-routed northward towards China.

Now India has woken up. China is reportedly doing the same thing that India did with its rivers in relation to Bangladesh. China does not find it necessary to consult, discuss, and sit down with India about the proposed diversion of waters from the Tibetan Plateau. There cannot be one rule for India and China, and another for India and Bangladesh.

There is another, wider, dimension on availability of fresh water. The increased demand for fresh water has prompted the construction of dams and barrages on international rivers, and it is reported that 60% of the world's largest rivers have been interrupted by the artificial structures. Many of them were built in agreement with riparian countries, and about 200 treaties are now in force for the management of common water resources.

Fresh water is getting scarce according to a Unesco study. The average supply of water is expected to drop by one-third within 20 years. Unesco points out that up to 7 billion people could face water shortages by 2020, and global warming may cause severe water shortages in 50 countries. South Asia is one of the regions to be adversely affected, partly because of melting of the Himalayan glaciers due to global warming.

Water experts believe that water disputes on intra-state and inter-state level may increase in future. It is the potential inter-state conflict over river water resources that may be of greater concern.

Barrister Harun ur Rashid is former Bangladesh Ambassador to the UN, Geneva.