NATIONAL 5 (Spotlight Weekly)]

Advance Shocks

A new study warns that the seismic strain building below the Himalayan region could release soon, triggering a major quake

By SANJAYA DHAKAL

In these times of political tremors, the recent issue of Science journal has triggered another jolt by predicting a major earthquake in the Himalayas -- encompassing the region including Nepal, India, Pakistan, Bangladesh and Bhutan that is home to one sixth of the global population.

The study, conducted by American geologist Roger Bilham and his colleagues, has predicted that a tremor above 8 Richter scale would hit this region "soon" -- meaning anytime between now and next 50 years.

The study states that the seismic strain/energy accumulating inside the Himalayas, thanks to the "push" by the Indian plate against the Tibetan plate northward, has only one way to get released --through earthquake. The Indian plate is said to be pushing itself inside the Tibetan plate at the rate of 2 cm per year, causing 5 to 6 big earthquakes every 200 to 300 years.

Buildinngs in Kathmandu : How safe

"Bilham's study only re-confirms what we have been saying," said Amod Dixit, renowned geologist and chief of National Society for Earthquake Technology-Nepal (NSET-Nepal). "Earthquake is our fate but we cannot predict the exact time of its occurrence."

Some 50 million people living in this part of the region could be affected by the quake, according to the study. "We cannot deny the scientific basis on which this prediction has been made. But the time cannot be pinpointed," said Madhav Raj Pandey, chief of the Seismological Measurement Center. The center has 21 survey offices to measure quakes across the country. Since 1994, it has been keeping a catalogue of all tremors above 2 Richter scale.

"In my view, the possibility of major quakes above 8 Richter hitting the western part of the country is greater. As Kathmandu was affected by the major quake of 1934, I think for the next 300 to 400 years tremors of such magnitude may not occur," said Pandey.

It has been established that it is not the quake but the falling structures that kill people. The danger for Kathmandu and other urban centers in the country lies in the haphazardly constructed buildings. A recent report by Japan International Cooperation Agency (JICA) has estimated that if the quake of 1934 was to recur in Kathmandu, 50 percent of the buildings would be affected. Likewise, nearly 12 percent of the population would be physically affected.

According to Dixit, who has closely studied the aftermath of Gujarat earthquake in January this year, which took 20,000 lives and destroyed thousands of buildings, a quake of a similar intensity could bring similar, if not greater, destruction in Kathmandu.

"More than 100 high-rise buildings collapsed in Ahmedabad city alone during the Gujarat quake. Even the new ones were destroyed for the simple reason that there were improprieties in their construction as well as design details. For example, there were no seismic considerations enforced in their construction and at places there were errors in detailing. Sometimes the angles of bends of horizontal confinement were wrong or the stirrups were unevenly placed or the quality of concrete was not good. The damage was largely because of negligence."

He says the situation in Nepal is similar to that in Gujarat. "Not only non-engineered houses but also engineered ones are death-traps. Thanks to the lack in detailing, even many frame structure houses are seismically unsafe."

Dixit prescribes "strict enforcement" of the existing building code to prevent poor construction. "What we have (building code) is a fantastic one. We do not need stricter codes but stricter implementation," he said.

Apart from the new constructions, which can be checked, the old buildings pose a greater threat. "There is a technology by which the old buildings can be retro-fitted to become seismically resistant. In fact, China did it with positive results after the 1975 quake. Though it involves huge investment, the government can encourage private individuals to do so and even do it in critical facilities like hospitals, water supply systems etc," Dixit said.

The only solution, according to Dixit, would be to "mainstream disaster management in development process." As they say, prevention is better than cure, the integration of disaster reduction system in development process would go a long way in allaying the present situation.