Twenty-nine workers were killed in a landslide at the Tehri dam.
Since Tehri is in an earthquake-prone region, the
authorities had settled on an earth and rockfill dam (such a dam can withstand
seismic vibrations) and not on a concrete dam.
The contractors responsible for constructing the dam said that the dam is strong but the mountains are weak ! The comment invites the question whether such a tragedy was foreseen ? What steps had been taken to protect the lives of the workers ? And who will bear the responsibility for the
accident ? The supervising official says it is everyone’s responsibility. They announced that the weak mountains would be strengthened. After the accident, the chief minister of Uttaranchal also visited the site and said that “In the future no such big
dams should come up in Uttaranchal”.
Whatever the causes of the disaster, it is clear that this accident has once again raised questions about the safety of the dam which is located in the fragile and highly seismic Himalayas.
The Tehri dam project has always been involved in controversies. The initial protests against the dam started in the late 1960s when surveys were conducted at the dam site.
The main opposition to the dam was on account of it being built in a highly seismic zone. In the event of an
earthquake a major disaster could occur, as the reservoir had been built at such a great height. The local protests focussed on this aspect of the dam.
A
committee appointed by the government refused environmental clearance to the dam. The then Prime Minister (Indira Gandhi) wrote that there is great local distress and a feeling that the contractors will be the main gainers. The voices against the dam
continued rising, however work on the dam continued. Another expert group also rejected the dam project, but nobody paid any attention.
The Bhumbla committee reviewed the project, and after considering various aspects such as siltation, seismicity and dam safety, again rejected the project. The authorities told the committee members that the dam structure was designed to withstand an earthquake of magnitude 7 on the Richter scale, but the committee concluded that this was not adequate as an earthquake of 8.5 magnitude was likely. But no revisions were made in the structure of the dam.
The tests showed that the deformation of the dam continued to increase right uptil 12 seconds when the test was terminated; the tests were not allowed to run for the full 30 seconds, which would be more representative of the Tehri situation.
The dam authorities have repeatedly said that the life span of the dam would be 100 years, but many experts disagree. As siltation may take place much faster, the life of the dam may be only around 30-40 years.
There are 125 villages which will be affected. The local people have sown rice again this year. They say that they have nowhere to go, and will prefer to drown when their village is submerged.
More abstracts about the Article: A dark tunnel