The second problem is population density. "The densest population sits in high seismic zones," he adds. The entire Himalayas, the Indo-Gangetic plane which covers the states of Uttar Pradesh, Delhi, Bihar, are all in the high seismic zone.
The challenge for India is to figure out what can be done in a country with an non-homogeneous structure not only in terms of the social aspects, but also in terms of income, says C.P. Rajendran, a fellow at the Centre for Earth Sciences at the Indian Institute of Science in Bangalore. "If you want to have a method of reducing the destruction of property in an earthquake, you have to understand that there are people who live in small shanties and people who live in big palaces," he says. "So there will be a completely different approach to both.
"You need to develop a strategy to suit the local ground realities and this is not a small task," says Rajendran.
Rastogi agrees: "If you take Delhi, for example, 50% of the city's population lives in slums and unauthorized colonies and that's just the official figure; the unofficial figure is much higher. So in a population of 15 million, we've got close to 8 million to 10 million people who are exposed to the effects of an earthquake."
Moving the at-risk population into structurally code-compliant buildings would take decades. Instead, Rastogi suggests audits be done of all the places in the city to gauge seismic vulnerability and potential damage.
"A lot of these places are not even accessible by ambulance, for example, or by fire brigades or by evacuation teams, so start there." Only then can a slow and gradual process of doing refurbishments to the existing structures to make them compliant begin, he adds.