Experts warn of heavy causalities even in moderate tremors

As Nepal reels under devastating earthquake, experts today warned that Indian cities like Delhi could suffer heavy casualties even in case of moderate tremors while pointing out the lapses in the building regulations of the country.

Noting that the condition and quality of Indian building stock is "poor", Centre for Science and Environment (CSE) said that India has many instances of buildings collapsing even without an earthquake and 70-80 per cent of buildings violate regulations in Delhi.

"It is estimated by experts that India is likely to report heavy casualties if a moderate earthquake struck, particularly in the large cities including Delhi. Ninety per cent of the building designs in the capital are either by the mason or the contractor.

"Newly-constructed houses rarely abide by the meticulous National Building Code-2005, Master Plan of Delhi-2021, Vulnerability Atlas-2006, building By-laws, or the housing construction, planning, development and regulatory authorities. The seasonal wear and tear demand is rarely met," Avikal Somvanshi, senior research associate at CSE.

Referring to the Tejendra Khanna Committee, set up in 2006 to look into various aspects of unauthorised constructions and misuse of premises in the city, CSE said that the committee found that 70-80 per cent structures had violated Building and Development Control Regulations.

The committee found that formalities required to obtain a building completion certificate or even a building plan sanctioned is "tedious" which is why the owners "seldom" procure them.

CSE said that in April 2011, the Delhi government made it mandatory for all builders to submit sanctioned building plans along with structural safety certificates for their new buildings which resulted in a drastic fall in the number of applicants for property registration and ultimately led to the revoking of the order.

Referring to a survey by the National Disaster Management Authority (NDMA), CSE said that it was found that in the last 25 years more than 25,000 human fatalities were caused primarily by collapse of buildings during earthquakes.

"The condition and quality of Indian building stock is poor when it comes to seismic performance -- in fact, the observed performances of reinforced concrete (RC) buildings are highly unsatisfactory," Somvanshi said. 

CSE said that the lack of regulations for construction and monitoring of buildings makes a huge proportion of them "unsafe".

"The large number of deaths in Nepal and India should immediately lead to a reflection on the nature of our buildings and whether these will be able to withstand an earthquake of moderate to high intensity," Anumita Roychowdhury, CSE's executive director for research and advocacy said.

CSE said that while building codes can apply to new buildings, there is also a need to retrofit existing buildings to make them safer.

"There are around 25 lakh such buildings in Delhi alone. However, while the know-how for retrofitting is in place, neither a survey nor an effort to initiate this massive project has begun," it noted.

Somvanshi said that during the 2001 Bhuj earthquake, RC buildings collapsed at an earthquake of just 6 on the Richter scale while a well-designed RC building is expected to collapse only when an earthquake is 7.5 or higher on the Richter scale.

"The damage caused to these buildings is unreasonably high as compared to any other country for similar level of ground-shaking," he said.

CSE noted that when it comes to approvals, research has shown that most builders get only the ground floor approved.

"Four to five floors are added once the completion and occupancy certificates for the ground floor are obtained," said a contractor during a research study conducted by Down To Earth, the magazine that CSE.

The Green advocacy body said that while India has a fairly good range of seismic codes covering a variety of structures, the key to ensuring earthquake safety lies in having a robust mechanism that enforces and implements these design code provisions in actual constructions.

"These codes are mandated for new construction but we have regular instances of buildings collapsing even in absence of earthquakes, which reflects how effectively they are enforced," said Somvanshi.