July 20, 2024, Saturday
Nepal 1:37:26 pm

Big Earthquake of April 2015 : damages and lessons learnt !

The Nepal Weekly
April 27, 2022

By Purna N. Ranjitkar l

At the midday of 2022 April 25, a massive earthquake shook Nepal. The magnitude of the earthquake was of 7.8 Richter scale. The natural movement was also called Gorkha earthquake denoting that the epicentre was Barpak village of Gorkha district.

The earthquake was felt throughout central and eastern Nepal, much of the Ganges River plain in northern India, and north-western Bangladesh, as well as in the southern parts of the Plateau of Tibet and western Bhutan.

An aftershock of the 6.7 magnitude took place on 26 April 2015 while hundreds of minor shocks were felt between those two major shocks. Around 400 minor shocks were after that.

Gorkha, Sindhupalchok, Dolakha, Bhaktapur, Kathmandu,Lalitpurand eight other districts were most damaged in Nepal. About 9,000 people were killed, many thousands more were injured, and more than 600,000 structures in Kathmandu and other nearby towns were either damaged or destroyed.

The earthquake produced landslides that devastated rural villages and some of the most densely populated parts of the city of Kathmandu. Initial damage estimates ranged from $5 billion to $10 billion. Inside Kathmandu, bricks and other debris from collapsed and partially collapsed buildings, which included parts of the famous Taleju Temple and the entire nine-story Dharahara Tower, filled the streets. The earthquake also triggered an avalanche on Mount Everest that killed at least 19 climbers and stranded hundreds more at Everest Base Camp and at camps higher up the mountain. Those at the high camps were soon airlifted to Base Camp, and all the climbers either hiked off the mountain or were flown out to other locations. Moreover, it was not a worst event to take maximum lives and damages as it was happened on a Saturday, so that school going children and office going workers were mostly safe at home or fields. Secondly, no hospital, no roads and no hydropower projects were damaged the earthquake. However, Dharahara on that Saturday was crowded with visitors and temple areas were also alike. So that more deaths and injured were found at such premises.

After earthquake, people came out to streets and try to find shelter at open places. The shelter was taken for more than two weeks. The open places of the Kathmandu Valley were much congested to provide shelter to all as even good and big house dwellers were out in the streets to be safe from earthquake consequences.  

The earthquake and its aftershocks were the result of thrust faulting (i.e., compression-driven fracturing) in the Indus-Yarlung suture zone, a thin east-west region spanning roughly the length of the Himalayan ranges. The earthquake relieved compressional pressure between the Eurasian tectonic plate and the Indian section of the Indo-Australian Plate, which subducts (underthrusts) the Eurasian Plate. Subduction in the Himalayas occurs at an average rate of 1.6 to 2 inches (4 to 5 cm) annually. Such tectonic activity adds more than 0.4 inch (1 cm) to the height of the Himalayan mountains every year.

The Himalayan region is one of the most seismically active in the world, but large earthquakes have occurred there infrequently. Before the 2015 temblor, the most recent large earthquake (that is, magnitude 6.0 or above) took place in 1988. That magnitude of 6.9 event resulted in the deaths of 1,500 people. A magnitude of 8.0 earthquake in 1934, that killed approximately 10,600 people. History says that such big earthquakes take place in Nepal in every 80 to one hundred years. The recent big earthquake was followed by big earthquake of 1934. As such, big earthquake may back in another 80 to 100 years. But that may happen even in between too or may be a few years later.

The preparedness for such a big natural crisis was proved to be a little. Mainly open spaces were not enough as many open spaces have been used in other purposes. Similarly, food and medical services were experienced needed to be reviewed for enhancement for a better service delivery as per requirement. In the villages and cities far from Kathmandu were also poorly served. Thirdly, the victims suffered more due to delayed and unmanaged reconstructions aids. They had torn tarp as roof to remain safe in the rainy seasons. Fourthly, clearing of debris was not managed. That took too long time to manage while artefacts of religious and cultural values were abandoned and some were misplaced or lost. Fifthly, modality for reconstruction priority adopted was wrong, so that foreign aids were expected for reconstruction of temples and buildings which local expertise could do in traditional methodology at comparatively lower cost as well. Similarly, priority identification should be focused on roads, bridges, utility infrastructures, residences, temples, monasteries, and cultural and religious values. But, reconstruction of Dahrahara was taken into top priority as a matter of national pride over the centuries old building with cultural and architectural values.

As such, preparedness is most important needed to face natural calamities which might take in any time, any size or magnitude. Particularly, to be prepared for earthquake in future, open space to maintain is first criteria while, food, medicines, utility supplies are also equally important to consider. Moreover, reconstruction strategies must be taken into consideration. The governmental mechanism to handle the possible crisis situations should be worked out well in advance too. Similarly, the building code with instructions to construct in earthquake proof technologies must be strictly followed. The temples, buildings owned by government or community or individual must be monitored for timey repair and maintenances. Traditional building technology must be restored for traditional architectures of cultural values and skills to be utilised in constructions and reconstructions. Likewise, knowledge on safety and rescue should be imparted to all citizens to manage and to be managed at any crisis situation.