The construction of Tipaimukh dam on the trans-boundary Barak River has raised hue and cry both in Manipur state in India and in Bangladesh. It is reported that Dr. Soibam Ibotombi of the Department of Earth Sciences, Manipur University, had written in an article that the "Tipaimukh dam is a geo-tectonic blunder of international dimensions." 

A parliamentary delegation from Bangladesh is expected to visit, and assess the impact of, the dam and report to the parliament in due course. The construction of dams on rivers for hydro-power is a much discredited technology, and its benefits are seriously questioned by experts.

Commercialisation of rivers arises because of the attitude that any river water passing to the sea is a waste and needs to be commercially used. The fate of the Colorado River provides an example of commercial approach. This fabled river reportedly dries up in the South Californian desert.

Interruption of the natural flow of rivers has not, in the long run, benefited countries. Some examples are given below.

Aswan Dam in Egypt (1970) has caused major agricultural and environmental problems. The increased use of artificial fertilisers in farmlands below the dam has caused chemical pollution, which river silt did not. Irrigation control has also caused some farmlands to be damaged by waterlogging and increased salinity, a problem complicated by the reduced flow of the river, which allows salt water to encroach further into the delta -- destroying some antiquities.

Due to the Aswan Dam inhibiting the natural fluctuations in water height, i.e. floods, the bilharzia disease has flourished, causing great problems for the Egyptian economy and people. The battle with the disease continues.

In China, the Three Gorges Dam on Yangtze River (scheduled to be fully commissioned in 2009 after 16 years of work) is the world's biggest hydro-power project, and some environmental experts say that it is "a model for disaster." Around the world, large dams are causing social and environmental devastation while better alternatives are being ignored.

If ever there was a lesson in the unintended effects of damming rivers, the Farakka Barrage is probably it. The Barrage is threatening to wreak havoc on a series of downstream villages and ultimately silt up the Kolkata harbour -- the condition it has been designed to fix -- apart from its adverse effects on Bangladesh.

The Barrage is now raising the possibility of two of the Ganges' major tributaries, the Padma (in Bangladesh) and the Bhagirathi (in West Bengal in India), merging, with unimaginable consequences. Some 20 km downstream from the barrage, the two rivers are less than 750 metres apart. Ten years ago, they were almost 3 km from each other.

Bangladesh has its own experience. In 1962, the then Pakistani regime constructed the Kaptai Dam in the Chittagong Hill Tracts for hydropower, with the total installed capacity of only 230 MW (currently 50 to 100MW is generated). Many books have been written questioning the overall benefits of the dam. Furthermore, the dam itself may become useless because of sedimentation of the Kaptai Lake.

The World Commission on Dams, in its report in 2000, having examined the technical, financial, economic, environmental and social performance of the dam projects, has concluded that the overall benefits of dams have not justified their financial, social and other costs.

Industralialised countries have gradually moved away from construction of dams on rivers and developing countries must not repeat their mistakes, water experts say.

In US and Europe, since 1998, the decommissioning rate for large dams has overtaken the rate of construction of dams, according to the World Commission on Dams. They have, instead, adopted an "ecological approach." This means that river resources must be harvested in such a way that no serious damage is done to the natural flow and course of the rivers and the eco-system they support, more so during global climate change.

Given the state of knowledge of various sources of energy, that India is reverting to a discarded technology in construction of Tipaimukh dam for hydropower is perplexing. India may take a pioneering role in pursuing the "ecological approach" in harvesting trans-boundary rivers that flow into Bangladesh.

Although India and Bangladesh are not parties to the 1997 UN Convention on the Law of Non-Navigational Uses of International Watercourses, the 103- affirmative votes of the countries in the UN show that the Convention indicates broad agreement as to how to use the waters of trans-boundary rivers -- such as the Barak River. India may abide by the principles of the Convention and demonstrate its leadership in the region.

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