The combination of densely populated areas in the city and the risk of climate-related hazards make Chennai vulnerable to disaster. A study brought out by Chennai Corporation, Kyoto University and the University of Madras only goes to prove this. It shows that northern parts of the city have lower resilience compared to areas in the south and west.
The recent earthquake and tsunami in Japan has awakened the curiosity of the residents on how prepared the city is in case of a possible calamity. Unlike the tsunami warning alert, there is no reliable technology to forewarn earthquakes. Much of the emphasis therefore is on how stringently buildings have adhered to the norms laid by the National Building Code.
The Tamil Nadu Common Building Rules for Urban Local Bodies is under the consideration of the State government. It would prescribe safety norms as a measure to protect buildings during natural calamities. If implemented, new constructions would require specific certification by professionals.
The one question that more people are asking now is: How capable is the city's infrastructure and buildings, particularly high rises, of surviving any natural disaster? Around 25 high rise structures are permitted in the Chennai Metropolitan Area every year.
The Fire and Rescue Services, one of the agencies that issue no-objection certificates to building whose height is above 15 metres, has so far given clearance to 964 high rise structures in Chennai and its suburbs. R. Nataraj, Director, Fire and Rescue Services, says the issue, however, is with buildings that are less than 15 metres tall and high rise structures that get the certification and subsequently violate by adding additional floors.
Vertical growth
Chennai Corporation is carrying out an analysis of 65,000 buildings with more than one storey to see how vulnerable they are to any calamity. The civic body's analysis of over 35,000 such buildings has been completed so far. The retrofitting measures would be recommended for the surveyed buildings.
With many high rise buildings, quite a few of them with 19 and more floors, getting ready to dot the skyline, experts say wind and earthquake resistance should be factors the developers should keep in mind while designing. However, the city does not have any body that certifies whether a building is earthquake resistant. A structural engineer can be approached and increasingly it is faculty members from IIT-Madras and Anna University who are approached.
According to C.V.R. Murty and Meher Prasad A., professors, Department of Civil Engineering, IIT-Madras, in bigger cities, including Mumbai, a tall building committee comprises experts from the field of building design and construction safety. In international practice, the complete design is over before the construction starts, whereas this is not the case here.CMDA vice-chairperson Susan Mathew says that the quality of construction of new structures in the CMA depend more on the “honesty of purpose of the structural engineers” who certify the building for earthquake resistance. She stresses the need for measures towards better monitoring of the quality of construction by local bodies in the CMA.
Developers agree that taller the building, the more the challenge as one needs to get more NOCs. “We adhere to the National Building Code (NBC) norms, but Chennai has a long way to go. We, for instance, have a material testing lab to test the strength of materials,” says V.S. Suresh, MD, Real Value Promoters Private Limited. He suggests that the approving authority should have a team that checks if the NBC regulation is adhered to and a panel of structural engineers be formed to certify.
Chennai is on Seismic Zone 3, which means it is on the moderate damage risk zone. The data about earthquake would be posted on the IMD website within 20 minutes. It is the Regional Meteorological Centre that co-ordinates with the State-level Disaster Management Cell only when there is a catastrophe warning when the magnitude is over 7 on the Richter scale, the officials said.
Y.E.A. Raj, Deputy Director General of Meteorology, RMC, says Indian National Centre for Ocean Information Services (INCOIS) at Hyderabad is the authorised agency to monitor ocean activity and tsunami. INCOIS would communicate to Central government and in turn that would be conveyed to the State government.
The awareness level among residents of several apartment complexes is equally low. A.V. Surendran, president of Welfare Association, Rajaji Nagar, Villivakkam, said the residents know only the fundamentals of things to do during earthquake. “We are planning to conduct mock drill about fire accidents in future.”
Officials from the Schools Education Department say that instructions were given to schools to equip students with life skills after the Kumbakonam fire tragedy but greater emphasis is needed to impart the skills on continuous basis. Much of such skills lie with individual schools to teach.
The Chennai Corporation has created a database of teams of volunteers who would react to any disaster. A total of 155 first aid teams have been constituted in the city with a total of 465 volunteers.
Other teams that have been constituted by the civic body include rescue and relief team, communication team, transportation team and carcass removal team.
(With inputs from Liffy Thomas, Aloysius Xavier Lopez and K. Lakshmi)
R.Nataraj, Director, Fire and Rescue Services: Fire drill should be mandatorily conducted at least once a year in a high rise building. The drills conducted now are not up to the scale that we want them to be. Fire extinguishers should be refilled once in six months and all the safety equipment should be in working condition. A mock drill alerts one to face any eventuality. Public should visit places that are safe and which have enough exit points.
Meher Prasad A., professor, Department of Civil Engineering, IIT-Madras: Earthquake causes different levels of intensity at different locations – higher near epicentres. Chennai is in Seismic Zone 3. With high rise structures coming up in the city, we need a tall building committee that will look into all aspects of design and construction safety. All designs should be "peer reviewed" by an independent agency, which should have the required professional expertise.
