Seismic shock: Worn-off instrument on job in Sardar Sarovar Dam area

Despite the Sardar Sarovar Dam being in a high seismic zone, the seismographs used in seven seismic data centres located in Gujarat, Maharashtra and Madhya Pradesh are obsolete, according to Sardar Sarovar Narmada Nigam Limited (SSNNL) officials.

Recently, a dialogue between SSNNL and Indian Seismological Research Centre (ISRC), Gandhinagar, was initiated to upgrade the seismographs at Kevadia colony, said ISRC officials.

While SSNNL authorities were not available for comments, B K Rastogi, Director General of ISRC, Gandhinagar, said: “All seismographs in the seven centres are worn out. There is a dire need to replace them with advanced instruments.”

SSNNL authorities will soon tie up with the ISRC for taking action in the matter, he said. A protocol dialogue between both the authorities has already begun. Rastogi said: “The instruments have been in use for over 10 years and will now be upgraded with the digitised version.”

Earlier, the seismographs were used just to record the frequency of an earthquake. The advent of digital seismographs, however, has helped in understanding the mechanism of an earthquake and the reason for deformity of any kind at the reservoir.

Officials at ISRC said: “It will take some time for the Centre to take out all the systems and replace them with state-of-the-art digital broadband instruments.”

In addition, the Global Positioning System will be installed at the centres. This could help in carrying out a detailed study on the dam.

When asked about the issue, Rastogi said: “We have been recording the tectonic movements measuring over 2.5 on the Richter scale at the reservoir. It is only the minute movements that we are unable to trace.”