Tehri, May 3: The debate over the feasibility and safety of the Tehri dam goes on - and may never be settled - but the latest controversy has once again pitted anti-dam lobbyists against the officials. Anti-dam activists, led by Sunderlal Bahuguna, allege that a ``crack'' has developed in the dam while officials say that facts show otherwise.A visit to site reveals that what is being called a ``crack in the dam'' is actually a crack in the plaster, 12 feet by 10 feet, at a height of 840 m, which has peeled off the slope of the Raika hills above Tunnel No 3.In all, there are four tunnels being constructed to serve as passageways for water from the Bhagirathi into the dam. The dam, scheduled to be completed by 2002, is expected to produce 2,400 MW of power besides providing drinking water and irrigation facilities in the area.Anti-dam activists allege that there is a crack in the dam structure while the fact is that the dam's main structure, a rock wall 260.5 m high, is yet to come up. What has beenbuilt so far is coffer dam to serve as the storage space for water.Bahuguna, who is under medical treatment in Rishikesh, told The Indian Express: ``I have been saying from the beginning that the Raika hills on the left of the reservoir are unstable and can fall any time. It had happened in Italy when adjacent hills had fallen into reservoir of a dam and made it defunct. It can happen in Tehri too. Thus independent geologists should be appointed to inspect the dam site."He also alleged that Tehri officials had marked the dam site a ``strictly prohibited'' area. ``If they have nothing to fear, why don't they allow a media team or experts to visit the dame site?'' Bahuguna said.Bahuguna's fear that part of the hill may subside and choke the reservoir is a possibility that officials say they have taken into account. And that's why they are building platforms on the hills.At the site of the so-called `crack', a platform had been built to prevent any subsidence due to a shift in the land mass. Aportion of this platform has given way.General Manager S C Sharma says that one reason the plaster peeled off could be because the engineers did not accurately map the rocky texture of the hill before constructing the platform. ``There is nothing to worry about,'' he says. ``Work on Tunnel No three and all other tunnels is on.''According to a construction expert, deep digging at four points in this hill has loosened the land mass. ``It's for this that we provide slopes by constructing platforms on the hill. All the hills surrounding the dam are to be given the platform treatment,'' he says.According to Sharma, the core committee of construction experts, who met on April 30, was apprised of the fact that plaster had peeled off. ``We told the experts that we have not found any geological surprise during the excavation so far. There are only some stresses in the hills when the tunnels were dug out and we have suggested three alternative construction methodologies to cope with these stresses. Thecommittee as well as we in the THDC want to convey that there is no need for panic,'' Sharma said.
