Events & Issues

New Delhi, 18 April 2011

Dialogue On Dams

SMALL IS BEAUTIFUL

                                                       By Radha Kant Bharti

In these days of acute water scarcity in India, inter-linking of river projects and construction of dams are very important. For the first time after decades, seven States Rajasthan, Madhya Pradesh, UP, Gujarat, Maharashtra, Andhra and Karnataka have realized the importance of inter-linking of rivers and finally given their nod for the same.

Needless to say, this will help resolve the problems of water scarcity and help in developmental projects. This comes on the heels of construction of dams which was one of the main developmental projects launched after India gained freedom. As India’s first Prime Minister Pt Jawaharlal Nehru felt that the dams would help develop India’s economic growth. He called these the symbol of modern India.

Indeed, food-grain production increased from 51 million tonnes in 1950-51 to almost 200 million tonnes by 1997. By March 1998 about two thirds of the installed hydro-power i.e. 21891 megawatt out of total generation capacity of 89000 megawatt, was attributed to dams.

Reviewing the progress made during 20^th Century it can be said that dams have contributed to an increase in food production, added to hydro-power capacity, provided water for domestic, municipal and industrial uses and helped to some extent in controlling floods.

But after two decades of completion of several multi-purpose River Valley Projects criticisms about their utility began to be voiced in different quarters. Not only people even senior technocrats and sociologists are doubtful and questioning the efficiency and benefits of large dams constructed on our rivers.

One of the most experienced engineers Bikram Singh Virk stated that he had supervised the construction of the Bhakhra dam on the Sutlej soon after Independence. Many other dams were built and dedicated to the nation subsequently.

However, after six decades of the programme, its negative effects have started appearing in downstream basins. The falling water table, receding vegetation cover, death of innumerable underwater species, declining forests and drying of deltas have forced many people to do a cost-benefits analysis of dams.

Most of the big river systems are in danger now and hardly a few of them complete their whole journey from source to sea. The report of the World Commission on Dams questioned their economics. The recent one by the World Wildlife Fund (WWF) entitled, “World’s Top Ten Rivers at Risk” is equally alarming.

According to the WWF report, river basins have been threatened by damming and the world’s 10 largest rivers hardly meet the sea as a result. The most endangered are Danube, Yangtze, Rio Grande, Salween, Nile, Indus, Ganges, Plata and Murry-Darling. The Nile that used to carry 32 billion cubic meters of water a year now carries only 2. The Indus in Pakistan, known as Asia’s Nile, has lost 90 per cent of its water in 60 years.

Globally, free flowing rivers, those moving at a distance of over 1,000 km are increasingly rare. Only 21 (12 per cent) of the world’s 177 longest rivers run free from the point of origin to sea. India’s Ganga has been threatened by over-extraction as 60 per cent of the river flow is diverted in canals for irrigation.

Same is the case with the Sutlej and Beas in Punjab, which are dry beyond Roper and Harike. The US, which has 5,500 dams, has stopped building dams. Huge funds are spent on resolving problems created by existing dams. Over 465 dams have been demolished there to correct the ecological defects caused by the stopped rivers in downstream areas.

A dam on a river causes water crisis in the river basins downstream due to reduced flow and the water table starts falling. Not all dams are built keeping this fact in mind. According to a World Bank survey 58 per cent dams were built without consideration of downstream impacts. America’s Hoover dam caused the waterbed to fall by 4 meters within 9 years of its completion. The falling water table of Indo-Gangetic plains is also due to the same reason.

Most riverbeds get eroded within a decade of damming. Sediments that flow through the river remain behind the dams reducing the soil health of the land downstream. It changes the pattern of flow, including volume and seasonal variations. Flowing is also reduced, necessary for native plants and animals. The flowing rivers flush back water channels, deposit nutrients on the land and replenish water lands.

When a river is reduced to a trickle, seawater is no longer flushed out of estuaries and intrudes in ground and surface water, causing salinity. The seawater reaches 40 km up in Indus in Pakistan and mingles with ground water, destroying water quality of the area.

The construction of dams on rivers, proved very fruitful in the initial years, but has started showing its ugly face sooner than later. It leads to weakening of soil health and depleting the water table in downstream areas. The solution lies only in freeing the course of the rivers. Let the water be stored and used for producing electricity, but it must be released in the river itself.

The real worry regarding dams is that the areas downstream would face the possibility of submergence in case excess water is released from the dams; discharge of water is standard practice when surplus water builds up putting extra pressure on the dam.

Then there is genuine fear that with a dam burst, the areas in the lower courses of the rivers would witness sudden and large-scale flooding. One of the major grievances is that the National Hydroelectric Power Corporation has not been transparent about the detail of its projects, and that it has not prepared a through impact assessment regarding flooding in the downstream area.

The construction of dam on rivers, though proved very fruitful in the initial years, has started showing its ugly face sooner than later. It leads to weakening of soil health and depleting the water table in downstream areas. The solution lies only in freeing the course of the rivers. Let the water be stored and used for producing electricity, but it must be released in the river.

Moreover, it has repeatedly been stressed that many of the mega dams do not possess the requisite flood cushioning components, which are considered vital in large dams.

Sadly, as a critical part of the democratic set up, the Opposition parties should have taken a serious view on dams, but till now there action in this regard has been no less dismal and disturbing. Perhaps, the Government and the Opposition might wake up when disaster strikes, by which time precious lives and land would be lost. The Moravi disaster, due to dam failure in Gujarat and recently the Kosi calamity in Bihar are burning examples.

Not only the people, but wildlife, flora and fauna also pay a heavy cost for the construction of big dams. In fact, every big dam project targets the rich flora and fauna first. Even the Government admits that vegetations suffered heavy losses and the forest cover decreased following the construction of dams.

As a result of the threat posed by big dams to nature, environment and a large segment of population, environmentalists and people are uniting against them. In fact, the agitation against big dams has become a people’s movement, which forced the Kerala Government to abandon the Silent Valley Project.

The big question: If big dams have become the symbol of destruction, what is the alternative? The answer lies in small projects and small dams in the basin areas. ---INFA

(Copyright, India News and Feature Alliance)