From ET Realty
For the last two years the geologist and scientist from all over the world have been predicting and publishing study reports about the anticipated shifting of the tectonic plates along the Himalayan belt. The accumulated stresses in the fault lines have gone beyond the point of rupture; the two recent earthquakes in Nepal, one in Sikkim and one in Manipur are a result of the rupture on the same fault line. All of these earthquakes have been towards the eastern portion of the fault line, and hence the chances of a counter balancing quake hitting on the western side have greatly increased. North India and Delhi-NCR lie in the direct vicinity of this danger zone. This has prompted the Ministry of Home Affairs to issue a warning through a National News Media on January 6 that North India could shortly witness multiple quakes of magnitude 8.2 or higher. What the Government warning does not address are the steps/action that the common citizen need to adhere to.
As a result of heightened earthquake threat in North India where there are numerous high density cities and townships, The Associated Chambers of Commerce and Industry (ASSOCHAM) on January 19 released a national study titled “Earthquake Safety – Are we prepared to face….?”. The quake warnings are serious more so as National Disaster Management Authority (NDMA) has estimated that the fatal casualties could be in the range of 8 to 9 lakhs.
India has the second highest population in the world, however not many know that India also has the maximum number of earthquake unsafe buildings in the world. Earthquakes don’t kill people but falling buildings surely do and this makes India the most vulnerable place on the planet.
Four Categories of Earthquake Resistant Buildings
As per NDMA guidelines earthquake resistant buildings are of 4 types. Unfortunately 100% of the buildings already built and under construction are of Category D. Even the most high profile buildings in India are being seismically designed only to Category-D standards.
- Category-A: Fully Operational – no damage and no interruptions due to the occurrence of the earthquake
- Category-B: Immediate Occupancy – minor damage but structurally safe for occupation and can be used immediately after the earthquake.
- Category-C: Life Safety – significant damage, can be used after the building has been retrofitted.
- Category-D: Collapse Prevention – major damage, the building cannot be used after the earthquake and needs to be discarded.
Building Codes and Structural Design Standards in India
Bureau of Indian standards is responsible for making, revising and updating the building codes in India. The Indian seismic code covers only the last category of earthquake resistance which is Category-D. The earthquake in Nepal has shown us how buildings in India will perform when the earthquake strikes. Nepal unfortunately followed the Indian Seismic Code and therefore even the modern buildings in Kathmandu have sustained very extensive damage. There are two main Indian seismic codes IS-1893 which has not been updated for 13 years and IS-13920 which has not been updated for 22 years. As the buildings in Nepal too were also designed and built to the Category-D standards they have suffered extensive damage.
Supreme Court Order on Earthquake Safety which has yet not implemented by the Government
Even after heightened seismic threat the Government has refused to implement the Hon’ble Supreme Court order vide its judgement dated 05 Dec 2014 on Public Interest Litigation No. 376/2014:
- NDMA undertake a public awareness campaign on a national basis through print and electronic media to educate the public about the four categories of earthquake resistant buildings and the detailed definition of each.
- All buildings housing more than 100 persons and all multi-storey buildings, more than 5 storeys high, both new and old should have an engraved metal plate mentioning that the Earthquake Resistant category of the building.
- The advertisements of all realty projects should include the earthquake resistant category as defined in NDMA document.
Recommended Approach towards Earthquake Risk Management and Building Seismic Resilience
- Government should undertake massive public awareness campaigns
- Builders should be mandated to explicitly spell out the earthquake resistant category of the building they are constructing and selling
- All buildings whose collapse can cause multiple deaths should have their earthquake resistant category prominently displayed
- Update the seismic codes of India and get them at par with countries like Japan and US.
- Corporates should use their good relations with Japan and import there time tested technologies of protecting buildings and other structures by absorbing the earthquake energy instead of resisting the same and getting damaged in the bargain.
- Government should incentivize the import of life saving technologies through reduction in import duties and easier bank loans. Lesser the damage to the built habitat after an earthquake easier it is for the Government to reach out to the population.
- People should be encouraged to exceed and better the minimum code standards. The concept of lower life-cycle costs of buildings needs to flow to the general population.
- International experience has shown that the maximum gains from earthquake management efforts are secured by strengthening the pre-earthquake preparedness and mitigation efforts.
- Simultaneously the Government authorities should also improve the country’s emergency response capacity
The prevalent high earthquake hazard, large exposure and high vulnerability indicate that urgent proactive action is necessary to save lives and property. NDMA has thus stated that retrofitting is not just an option, but a national urgency. There are valuable experiences of countries like USA, New Zealand, Turkey and Italy, which have undertaken large programs for seismic retrofitting of buildings and structures spreading over decades. India can immensely gain from the experiences and challenges faced by these nations for seismic retrofitting programs.