• NBRO to establish national building code

A potential earthquake in India poses no immediate threat to Sri Lanka, local experts reassured after Indian scientists warned about the possibility of earthquakes in the Uttarakhand region in India. 

This comes in the backdrop of Indian National Geophysical Research Institute (NGRI) Chief Scientist Dr. N. Purnachandra Rao revealing to Indian media last week that the Himalayan region remained highly vulnerable to tremors, with Uttarakhand likely to “witness a massive earthquake any time” of a magnitude “similar to or more than Türkiye”. 

In the wake of the recent earth tremors of a minor scale experienced in Sri Lanka over the past few months (especially in the aftermath of the Türkiye quake), concerns abound over the likelihood of earthquakes in Sri Lanka. 

Rao claims that an earthquake of 8-plus magnitude is likely to occur in the Himalayan region given the stress that is building up beneath the surface of the Uttarakhand region, which lies within a ‘seismic gap’ – a region along an active fault where stress is accumulating because no earthquakes have occurred there recently. Scientists often consider these regions to be high-risk areas for earthquakes in the near future.

Possible impact on Sri Lanka

Following Rao’s revelations, University of Peradeniya Professor of Geology Atula Senaratne said Colombo and Jaffna would feel the impact of any powerful earthquake occurring in the Himalayan range as predicted by Indian geologists. 

Speaking to The Sunday Morning, Senaratne said the forecast from the National Geophysical Research Institute could not be discounted. “The NGRI is a renowned institute in India and there is validity to its forecast. Although we do not know when and where such an earthquake may happen, we will have to consider the possibility.”

As he noted, the impact of an earthquake depended on its intensity, which was usually indicated by its place in the Richter scale. “An earthquake of magnitude 5 on the Richter scale occurred in 2020 and was felt in Colombo and Jaffna. 

From a geological point of view, if a 5 on the scale is felt in Colombo, a quake of magnitude 8 or more will definitely be felt,” he said, noting however that since it was only a forecast, the chances of an earthquake could go either way but that it was necessary to be prepared for it.

He said that should an earthquake occur, the impact in India could be similar to Türkiye as claimed by the NGRI, but Sri Lanka would not feel a similar impact given the distance and that it may only feel “strong ground movement”. 

GSMB says no cause for concern

Experts at the Geological Survey and Mines Bureau (GSMB) stressed that the possibility of a serious impact was low and that there was no cause for concern. 

Speaking to The Sunday Morning, GSMB Acting Director General M.M.J.P. Ajith Prema emphasised that earthquakes could not be predicted, noting that while scientists made attempts to predict earthquakes based on past data, it was impossible to pinpoint the exact date or time that an earthquake could occur. 

GSMB Senior Seismologist Nilmini Thaldena said that due to the distance from the potential epicentre, it was not likely that large-scale damage would occur should there be an earthquake in the region as claimed. “There is a great distance between us of about 2,800 km. When considering this distance, it is unlikely that we would experience damage to the extent of collapsing buildings should there be an earthquake of the type mentioned by the Indian geologists.”

She further noted that as the Himalayan region was prone to earthquakes, being a plate boundary there had been earthquakes of magnitude 7 or 8 previously, but this had not affected Sri Lanka.  

GSMB Senior Geophysicist Mahinda Seneviratne echoed the thoughts of his colleagues – that the possibility of an impact for Sri Lanka would be very low. “It would depend on the magnitude of the earthquake, but the likelihood of any impact on Sri Lanka is low. For instance, even in the case of earthquakes that took place within closer distances such as the 2004 Indonesian earthquake of magnitude 9.4, there were minor tremors in Sri Lanka but nothing more than that,” he explained. 

Previous quakes in the Himalayan region

Moreover, the Himalayan region has experienced earthquakes previously, for instance the magnitude 7.6 Bhuj earthquake of 2001 of which the intensity had been felt only up to about Chennai. 

Accordingly, as per previous data and lessons learnt, the prospects of an impact on Sri Lanka were minuscule, although if there was an earthquake in South India, it may be felt in northern Sri Lanka, Seneviratne explained. 

Nevertheless, the GSMB continued to monitor the situation constantly, he noted. As the GSMB Acting Director General explained: “There are currently four seismic stations operating in the country. If an earthquake occurs, we have the capability of informing the country. The Pallekele centre operates regionally and can monitor all earthquakes in the surrounding region of the Indian Ocean. Moreover, there are three other centres in Buddhangala, Mahakanadarawa, and Hakmana that receive seismic data. Further, GSMB officers monitor seismic conditions 24/7 at these four centres.”

NBRO to introduce national building code

National Building Research Organisation (NBRO) Director General Eng. Dr. Asiri Karunawardena, speaking to The Sunday Morning, also noted that due to the distance between the Himalayas and Sri Lanka, the impact would be less. 

Stressing that the devastation could vary depending on multiple factors which differ from one geographic area to another, he said: “In order to damage buildings, there has to be adequate energy to shake the building and loosen the foundations. However, once such an earthquake takes place in India, the energy transferred to Sri Lanka will be at a minimum level. Therefore, I don’t believe that that kind of energy would cause any harm to well-engineered buildings.”

Addressing Sri Lanka’s level of preparation to face any potential earthquakes, Karunawardena noted that in the construction of high-rise buildings, for instance, earthquake resilience was typically considered. “In the Sri Lankan context, most high-rises may be safe, but in case of a poorly constructed building, there can be some impact.”

In this context, the NBRO is taking steps to implement a national building code to ensure that buildings are structurally sound. “At present, there are no regulations as such but it is up to the engineer to use the best practices in construction. Therefore, we realised it was important to adopt a building code which would implement regulations.”

Accordingly, the NBRO, the Urban Development Authority (UDA), and the Construction Industry Development Authority (CIDA) have taken initiatives to develop a building code for Sri Lanka, which will enforce minimum requirements for the construction of any buildings in future. 

Moreover, in the event of an earthquake, the Disaster Management Centre (DMC) is prepared to take action, DMC Director General Major General (Retd) Sudantha Ranasinghe shared. “If there is an earthquake, the DMC’s task is to help through search and rescue, medical aid and facilities, and evacuation. There are trained soldiers for this; we prepared a team to be sent to Türkiye as well and they are here in Sri Lanka now on standby.” 

According to GSMB Acting Director General Ajith Prema, measures have been taken in terms of preparation and early warning mechanisms for earth tremors/quakes. “The GSMB, along with the DMC, NBRO, medical institutions, and the fire brigade held a round of discussions recently, during which certain decisions were reached. This includes public awareness programmes to dispel fear among the public in the near future,” he said.