The centre Wednesday asserted before the Supreme Court that there was no basis for the fear that the Bhagirathi river, on which the Tehri dam was built, would disappear with the water flowing into aquifers.

In its response to a petition by Sureshwar Sinha on the issue, the centre said it was based more on hypothesis than facts.

"It may be incorrect to assume that sub-surface flows have started and that the river is flowing in its aquifer around and below Tehri dam," it said.

The petitioner was apprehensive of the river disappearing underground and prayed for urgent steps to prevent this from happening.

Allaying the fears, the centre said the dam and its surrounding areas had been extensively studied by the Geological Survey of India using various methods, including satellite data and digital image processing and no such thing as a deep aquifer near Tehri dam reportedly existed.

"As such there is no deep-seated major fault existing in the close vicinity of the dam site as given in the hypothetical model presented by the petitioner," the centre said.

On Sinha's contention that the dam water seeping through the fault in the South Asian tectonic plate on coming in contact with magma would cause a major disaster, the centre said: "Any hypothetical situation leading to thermo chemical reactions referred due to water coming in contact with deep seated magma is a highly unfounded conjecture."

A three-judge Bench comprising Justice Y.K. Sabharwal, Justice B.N. Srikrishna and Justice P.P. Naolekar adjourned the hearing, taking on record the centre's response and those filed by the Uttaranchal government and others.