A case for quake proof cityscapes

The death toll of the 7.8 magnitude earthquake that hit Turkey and Syria has touched the 40,000 mark. India had also borne witness to a 7.7 magnitude quake in Bhuj in 2001, followed by one in Kashmir in 2005. Several high intensity quakes have been recorded in the 21st century. Notably, the 9.1 magnitude quake that struck off the coast of Sumatra in 2004 claimed over 2.3 lakh lives, after it triggered tsunami waves that were up to 50 meters high.

Earthquakes have become more frequent since the past century. Improvements in quake detection technology and a surge in the number of sensors could be why such incidents have been reported more often. Although the incidence of high intensity quakes are relatively low, the destruction and casualties have spiked owing to a growth in population in densely constructed urban areas. Such disasters are a wake-up call for India. Urban planning experts believe that casualties in Turkey and Syria could have been reduced had the officials in the affected areas not stood party to flagrant violations of building code, and substandard quality construction.

Interestingly, sections of the Indian peninsula lie in a seismically tension-prone zone, a region where the Eurasian and Indian tectonic plates merge. Around 59% of India is susceptible to quakes of varying magnitudes. About 11% falls within the very high risk Zone V (which includes the Kashmir Valley, eastern Uttarakhand, western Himachal, northeast India, and the Rann of Kutch). About 18% of the nation falls within the high risk Zone IV (which comprises New Delhi, UP, Haryana, Bihar, West Bengal and regions in Maharashtra). Finally, 30% of India is classified under Zone III (Lakshadweep, Goa, Kerala, and parts of Chhattisgarh, MP and Jharkhand).

Such geographic divisions have necessitated the creation of specific sections pertaining to earthquake-resistant construction in the National Building Code (NBC) 2016. But, there are no laws mandating compliance from developers with regard to these safeguards. The situation in India is no different than that of Turkey on issues of construction amnesties.

In Turkey, the government has admitted that over 50% of the buildings were constructed against the building code. A construction amnesty passed in 2018 helped legalise older substandard buildings erected without proper permits. A small fee for this legal exemption was all it took for violators to get away with projects that lacked basic safety requirements. This week, Ankara has cracked down on contractors in reaction to the widespread anger of people and has begun investigating over 163 people in this regard.

In India’s national capital, 90% of buildings run the risk of collapse in the event of a strong quake. Three years back, the Municipal Corporation of Delhi had compiled a safety audit policy to protect buildings from quakes. But the initiative tanked as the responsibility of conducting and paying for the audit was placed on the end consumer.

Here in Chennai, after the collapse of a 11-storey apartment block (under construction) in Moulivakkam, the Justice R Regupathy Commission recommended the reconstitution of the CMDA, through the formation of a committee of multi-disciplinary experts. Experts say there is a need to create a greater awareness among the public on matters concerning NBC guidelines and inspire voluntary compliance to incorporate earthquake resistant changes in buildings, which will entail an additional expenditure of 3 to 4% in construction cost. Municipalities should also be encouraged to adopt the NBC framework when drafting their building bye-laws.