Panic reaction to earthquake is no way of facing the calamity

Panic has gripped Dhakaites as an earthquake shook their residences violently on Friday, November 21. Another tremor, thought to be the aftershock of the Friday's one, jolted the capital and other areas the next day. This was followed by three more mild quakes, considered again the aftershocks of the first, on Thursday last. So, if the residents of the chaotically built megacity--- now the second most populous urban centre in the world with 36 million inhabitants after Jakarta--- get panicky, they cannot be blamed.

Residents of Dhaka City remain oblivious of the fact that this sprawling urban host is sitting on a seismic time bomb. But the five tremors within a week have struck terror into their bosoms and some people have left the city for shelters in less populous areas close to the city's periphery. The idea is that they would commute to the city from their far less risky accommodations to mind their businesses or attend offices. What they forget is that an earthquake may choose the fractional coincidental time they will spend in the city to strike. Those who can avoid visiting the city may count them lucky. But families with school-going children cannot afford the luxury of shifting their accommodations away from the city. Also, the areas surrounding the epicentre of November 21 quake and at a short distance from it are no less, if not more, at risk.

Of great concern is the fact that the epicentre of all five tremors was in Narasingdi, not at a great distance from Dhaka City. The closer the epicentre is the greater the risk for people living in buildings not constructed as quake-tolerant structures. Also, the existence of another tectonic 400-kilometre long fault line stretched from Jamalpur and Mymensingh upto Kolkata is quite unnerving. This is capable of giving rise to a quake measuring a magnitude of 6.0 on the Richter Scale at the maximum. Since all five tremors have originated from nearby locations, the last four can be considered the aftershocks of the first. This probably means that the danger feared by most people is over now. Aftershocks have never been as severe as the original quake. In case of severely damaged buildings and other structures by the original quake, the aftershocks can be fatal. So, the cracked or tilted buildings are at risk of collapsing by the aftershocks. Residents from such accommodations should stay away.

Those who think that the mild jolts are a rehearsal of a quake of cataclysmic proportion are most likely to have reached a conclusion out of fear, not from the rational standpoint. This does not however rule out a powerful quake in the future that might wreak havoc with the majority of buildings in Dhaka and other urban centres around it. Much will depend on which tectonic plates collide or slide underneath another. The greatest danger is from the Indian tectonic plate that meets the Eurasian plate with the former moving under the latter at the meeting points. This also depends on the energy accumulated in the fault lines for hundreds of years seeking its release as a result of collision or subduction of tectonic plates.

These are subjects of geologists and quake experts. So, it is better to rely on their expert opinions. They have made it quite clear that the last four tremors were aftershocks of the original quake measuring 5.7 on the Richter Scale. If this is so, most likely this time Dhaka and other areas already affected may be out of danger. But it is always wise to be cautious and get prepared for any eventuality. No compromise on the advanced technologies for protection of new buildings from powerful quakes should be made. The Rajdhani Unnayan Kartipakkha (RAJUK) must exercise its authority to ensure that one of the commonly used advanced technologies in Japan is replicated here for high-rise buildings on consideration of costs. Even retrofitting of old multi-storey buildings is possible but the expenses are likely to be forbidding.

Panic reaction, however, is no solution to the problem of concrete jungle that Dhaka today is. The situation of haphazard development of the city has to be analysed objectively. Escape from a tragic death caused by a quake is hardly a choice. One will embrace such an eventuality depending on one's stay at the time and that time is unpredictable. Science is yet to be so advanced to predict the timing of such a calamity. It is, therefore, wise to face the reality courageously and continue working as usual.