Tehri Project at Last Tehri: An environmental hazard?

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Sunderlal Bahuguna, who won the Magsaysay award for the Chipko movement (whatever happened to Gaura Devi, the intrepid woman of Reni village of Chamoli district who had actually initiated the movement?) was the person who had opened the eyes of many a would be-environmentalist like this writer, by repeatedly; undertaking fasts against the construction of the Tehri Hydro-electric project. A visit to the project site in January 1990 revealed the other side of a picture ,the most important of which was the assertion by a Soviet consultant engineer to the project that even if a nine magnitude earthquake were to hit the dam 15 kilometre below the surface, it would withstand the tremor.

The erstwhile Soviet Union was originally associated with this project with the USSR president assuring Prime Minister Rajiv Gandhi an aid package of 1000 million roubles for the scheme. A number of Soviet consultants were sent to Tehri, the leader of the team being Engineer Davidof had made the assertion.

The Tehri Hydro-Development Corporation (THDC), a joint venture of the Centre and the Uttar Pradesh (now Uttaranchal) had been harried by continuous propaganda about the vulnerability of the proposed dam from earthquake. An environmental group appointed by the Ministry of Environment and Forests to go into the environmental impact assessment of the project, led by a well known soil scientist, went to the Tehri area and a few days later, gave a report saying that since an earthquake of 8.5 magnitude was about to hit the area, the project did not merit environmental clearance and should be scrapped.

This had flabbergasted the government. Here was a team led by a soil scientist having no knowledge of earthquake engineering or seismicity, and his entire team having no qualified seismologist, declares that a 8.5 magnitude earthquake was to hit the area without having received any mandate from the government for undertaking such a study! The Union Government, therefore, set up a five-member High Level Committee led by Shri D.P. Dhoundial, Director General of the Geological Survey of India in order to look into the seismicity, RIS(reservoir-induced seismicity) and related safety aspects of the Tehri Dam Project. Other members of this team were: Dr. V.K Gaur, Eminent scientist, Dr. C.D. Thatte, Member of the Central Water Commission, Dr. D. Guptasarma, Director, National Geographical Research Institute and Prof. L.S. Shrivastava, Head of the Department of Earthquake Engineering, Roorkee University.

One may mention here that Dr. V.K Gaur was one of the strongest critics of the project and he was deliberately included in order to give full opportunity to an opponent of the Dam to have his views recorded.

Yet, along with our other members, he appended his signature to the conclusion arrived at by this team that ?all dangers arising out of seismicity have been taken note of and taken care of in the planning of the Tehri Dam Project?

This report as also Dr. Gaur'sendorsement had created a sensation among the environmentalist lobby, three journalist members of this lobby thereupon had asked the Secretary of the Ministry of Environment and Forests to resign, creating an impression that the issue was one of conflict between the Ministry of Environment and Forests and the Ministry of Steel and Mines, which had constituted the High Level Committee.

When in October last year a strong earthquake had hit the Kashmir area on both sides of the Line of Control (LoC), not a single dam in the area including the Tehri Dam and the Tarbela Dam of Pakistan on the Indus had been affected. Not even the Dam across the river Jhelum at Uri, on the Indian side of the LoC, built for a 480 MW hydro-electric project, was affected although Uri was the worst hit town in Jammu and Kashmir this side of the LoC. Modern technology is capable of making dams safe against earthquakes.

In mid-July 2006, one of the four 250-MW turbines of the 1000-MW project, started producing electricity which is now feeding Delhi too. Very soon the other three 250 MW turbines would be synchronized and connected to the grid.

It is now necessary for the Union Government to accord sanction first to the 400 MW Koteshwar project, about 22 km downstream of Tehri, where a 97.50 metre high dam is being built for this run-of-the-river power project. This dam, the storage of water behind which is changeable daily, has been designed to regulate water releases from Tehri reservoir for irrigation. This dam is scheduled to be commissioned in 2007-8.

The Tehru Pumped Storage Plant, which will utilise the Tehri and Koteshwar reservoirs as the upstream and downstream reservoirs is designed to have an installed capacity of another 1000 MW of electricity. The Centre has yet to accord sanction for this scheme.

The Tehri project will produce now 3568 million units of electricity, and 6200 million units every year on full completion of the project. The waters from the reservoirs?upstream and downstream of the dam, will provide additional irrigation to 2.70 million hectares of land and stabilise the existing irrigation for 6.04 lakh hectares in Uttar Pradesh. The State of Uttaranchal will receive 12 per cent of the power produced at Tehri free of charge.

Following the objections by certain groups that the impounding of waters of the Bhagirathi behind the dam will affect the self-purificational property of the waters of this holy river, the THDC has provided a 400 millimetre diameter pipe running through dam at the intermediate level outlet having the capacity to carry 35 cubic foot per second of Ganga water continuously in order to satisfy these elements that the self-purificational property of the water even downstream of the dam will not be affected. Nevertheless, the National Environmental Engineering Research Institute (NEERI), Nagpur, has given the verdict that the waters of the Bhagirathi which will move through the dam and after generating electricity will re-join the mother river, will not lose its self-purificational property

For the people of Delhi, the Tehri project will provide 300 cusecs (162 million gallons per day) of drinking water from the dam. It will provide 200 cusecs for some towns in Uttar Pradesh.

The THDC has built a new township, called the New Tehri Township (NTT) has been built high up in the hills to rehabilitate most of the people displaced by the Project. Other rehabilitation projects were also taken up.

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