Create seismic resilience

Even a mild shaking of earth sends shivers down our spine! Living in Jammu and Kashmir, which falls under the high seismic zones, we frequently witness earthquakes.

A jolt beneath our feet brings alive the horrific memories of the 7.6 magnitude earthquake in October 2005 which caused massive loss of lives and razed thousands of structures to the ground. Two decades on, we haven’t learnt lessons from the devastating earthquake! There is no regulation on constructions in earthquake vulnerable areas. In the race of so-called development, J&K is seeing a boom in construction of multi-storey buildings.

We need to understand that geological and tectonic settings in Himalayan ranges trigger intense tectonic activity affecting the Kashmir basin in North-West Himalaya. At these places, Indian and Eurasian plates collide creating massive mechanical stress which gets released in the form of earthquakes. We should not panic due to fear of earthquakes but we have to be always ready. We are literally sitting on earthquakes!

We should not forget the study by prominent United States-based seismologist Roger Bilham warning that the Kashmir valley could have an earthquake of largest ever magnitude 9. However he has not specified any timeframe. Bilham’s study states that a magnitude 9 earthquake can trigger landslides that would dam the Jhelum River, which drains from the Kashmir valley into Pakistan side of Kashmir.

That could put Kashmir valley under water within three months. Based on his Global Positioning System (GPS) data readings, Bilham reveals that the gradual movement of rocks in the Zanskar mountains, north of the Kashmir Valley, show that earlier estimates of the maximum possible quake in the region were too low. In this region, the Indian plate is slowly burrowing under the Tibetan plateau. Studies on where the relative movement of the Tibetan plateau was slowest indicate where compression is building up, and a rupture is eventually likely to occur.

Bilham, who visited Kashmir in 2007, states this zone is likely to rupture when a quake eventually happens could be 200 km wide, rather than about 80 km. “The zone would encompass the Kashmir valley – including the city of Srinagar, home to some 1.5 million people. If slippage occurs over a length of 300 km, as is possible, a mega-quake of magnitude 9 is the likely result. Given building codes and population in the region, that could mean a death toll of 300,000 people,” the study states.

Another study “Site Effects Investigation in Srinagar City of Kashmir Basin Using Microtremor and Its Inversion” states that Srinagar region, which is J&K” summer capital is exposed to high seismic risk. In order to gain insight on potential site effects and subsurface structure of the region, the study was conducted by S Vishal Gupta Imtiyaz A Parvez, Ankitb , Prosanta K Khana , and Rakesh Chandra of Department of Applied Geophysics, Indian Institute of Technology (Indian School of Mines), Dhanbad, India; CSIR Fourth Paradigm Institute Bengaluru, and Department of Earth Sciences, University of Kashmir, Hazratbal, Srinagar respectively.

The study was carried out using extensive high-resolution microtremor ambient noise surveys at 429 locations in Srinagar. The HVSR curves showed the peaks in the range of 0.22 Hz to 9.96 Hz indicating heterogeneous and complex sedimentary cover in the region. Inversion of the HVSR curves gives the shear waves velocity distribution which highlights two distinct reflective surfaces in most of the areas. In addition, they also used the estimated fundamental frequency of various types of houses/buildings located in Srinagar city to assess the possibility of resonance in case of occurrence of any earthquake. This study adds a value to the region in earthquake engineering, seismic hazard and risk evaluation purpose for Srinagar and its suburbs.

There has been an increase in tectonic activities in the Pir Panjal and Zanskar range. The Chenab Valley, housing huge dams including Dul Hasti in Kishtwar and Baglihar in Ramban is vulnerable to earthquakes. The vulnerability of the geologically-young, unstable and fragile rocks in Doda have increased manifold due to various unscientific developmental activities.

Amid this gloom, there is hope. An event “Enduring Appeal of Traditional Architecture: Lessons for Modern Construction” organised by the Indian National Trust for Art and Cultural Heritage (INTACH) Kashmir chapter on June 14 is important. More than bridging Kashmir’s architectural heritage and modernity, the experts in the event highlighted how traditional Kashmiri architectural practices based on climate responsiveness, seismic resilience, can serve as vital models for more sustainable and context-sensitive construction in the 21st century.

In previous earthquakes, it has been observed that houses constructed with traditional methods did not face much more damage than concrete constructions, especially column structures. It is mainly due to the flexibility of structures constructed with mud and wood. Now the whole landscape is changing. We are witnessing traditional houses being reconstructed in a modern way. This can be detrimental during earthquakes, this can be the difference between life and death!

We need to learn from Japan, which witnessed powerful earthquakes, regarding quake preparedness. Japan has strict building codes so that structures are designed to withstand shaking. The structures have flexible foundations that allow buildings to sway with the earthquake’s energy.

We need to encompass building codes and develop early warning systems.

We must accept the fact that we cannot prevent earthquakes. All we can do is to minimise damage. It is the responsibility of the government and stakeholders to build earthquake resilient society. There is no harm to organise disaster management awareness and training programmes across J&K. We also need to strengthen our Emergency Response Centres besides rescue and rehabilitation mechanisms.

We need to adapt ourselves to deal with earthquakes as we will never be able to prevent this natural phenomena.

Author is Executive Editor,

Greater Kashmir