2015 Nepal Earthquake: The Gorkha Quake and Everest Avalanche

The 2015 Nepal earthquake, also called the Gorkha earthquake, struck central Nepal shortly before noon on 25 April 2015. With a magnitude of 7.8, it was the country’s most powerful earthquake in more than 80 years, killing nearly 9,000 people, destroying around half a million homes and toppling historic temples in the Kathmandu Valley. It also set off a deadly avalanche on Mount Everest and a landslide that buried an entire village in the Langtang valley.

Why Nepal shakes

Nepal lies along one of the world’s most active collision zones. The Indian tectonic plate is pushing north into the Eurasian plate at around 4-5 centimetres a year, a process that has built the Himalaya over tens of millions of years. Strain builds up on a great fault beneath the mountains, the Main Himalayan Thrust, and is released in large earthquakes.

The last comparable disaster was the Nepal-Bihar earthquake of 1934, which devastated the Kathmandu Valley and northern India. Seismologists had long warned that another great earthquake was overdue, and that Kathmandu, a fast-growing city of crowded brick and concrete buildings, many built without engineering, was highly vulnerable. Similar warnings had been made after earthquakes elsewhere in the region, such as the 2005 Kashmir earthquake.

The earthquake

The main shock struck at 11:56 local time on Saturday 25 April 2015. Its epicentre was near Barpak in Gorkha District, about 80 kilometres north-west of Kathmandu, at a shallow depth of roughly 8-15 kilometres. The rupture spread eastward for about 150 kilometres beneath the Kathmandu Valley, and violent shaking lasted around a minute.

Because it was a Saturday, the weekly holiday in Nepal, schools were closed, which experts believe prevented many child deaths. In rural districts, however, people were often at home, and stone-and-mud houses collapsed on their occupants. The ground beneath Kathmandu was lifted by about a metre.

Hundreds of aftershocks followed. On 12 May 2015 a second powerful earthquake of magnitude 7.3 struck east of Kathmandu, in Dolakha District near the Chinese border, killing about 200 more people and bringing down buildings already weakened by the first shock.

Destruction in the Kathmandu Valley

In the capital, newer reinforced buildings mostly survived, but older houses, temples and poorly built structures collapsed. The nine-storey Dharahara tower, built in 1832 by Prime Minister Bhimsen Thapa and a popular viewpoint, fell almost entirely, killing many people who had climbed it on the holiday; reported figures vary from several dozen to about 180.

The Kathmandu Valley World Heritage Site suffered severe damage. In Kathmandu’s Durbar Square the ancient wooden Kasthamandap pavilion, from which the city is thought to take its name, collapsed, along with several temples. Monuments in Patan and Bhaktapur and the great stupas of Swayambhunath and Boudhanath were damaged. UNESCO and many foreign experts later helped to restore them.

The rural hills and the mountains

The worst-hit areas were in the hills around the epicentre and north and east of Kathmandu, in districts such as Gorkha, Sindhupalchok, Nuwakot, Dhading and Rasuwa. Sindhupalchok alone recorded more than 3,000 deaths. Landslides blocked roads and rivers, cutting off villages for days or weeks, and helicopters were often the only way to deliver aid.

On Mount Everest the shaking released a huge avalanche of snow and ice from the slopes above Base Camp, which swept through tents during the busy spring climbing season and killed about 22 people, mostly Nepali Sherpa and other mountain workers, making it the deadliest day in the mountain’s history. In the Langtang valley north of Kathmandu, an enormous avalanche and rockfall buried Langtang village, killing an estimated 250 to 350 residents, trekkers and guides.

Response

The Nepali army, police and volunteers led rescue efforts, supported by search-and-rescue teams and military aircraft from dozens of countries. India launched its relief mission, Operation Maitri, within hours, and China, the United States, the United Kingdom, Israel and many others sent teams and supplies. Kathmandu’s single international airport, with one runway, quickly became congested.

About 2.8 million people needed humanitarian help, and many families lived in tents or temporary shelters through the monsoon and the following winter. Nepal’s government, led by Prime Minister Sushil Koirala, faced criticism for slow and centralised distribution of aid in the first weeks.

Recovery and rebuilding

A government needs assessment put the total damage and losses at about 706 billion Nepalese rupees, roughly 7 billion US dollars, equivalent to about a third of the country’s annual economic output. At a donor conference in Kathmandu in June 2015, international partners pledged about 4.4 billion dollars.

Reconstruction was slow at first. Political disputes delayed the creation of the National Reconstruction Authority until December 2015, and a blockade of fuel and goods on the border with India from September 2015 to February 2016, linked to protests over Nepal’s new constitution, deepened shortages. The disaster had helped push Nepal’s divided parties to finalise that constitution, promulgated on 20 September 2015.

Over the following years most damaged homes were rebuilt with government grants that required earthquake-resistant designs. A rebuilt Dharahara tower opened in April 2021, and a restored Kasthamandap was completed the same year, using traditional techniques and timber.

Lessons and preparedness

Scientists studied the Gorkha earthquake intensively, using satellite radar, GPS stations and seismometers. They found that the rupture had released only part of the strain stored along this section of the Himalayan front; the shallow part of the fault, nearer the surface to the south, did not break. Many seismologists therefore warn that further great earthquakes remain possible in central and western Nepal and neighbouring parts of India.

The disaster also showed that preparation saves lives. Hospitals and schools that had been retrofitted under earlier safety programmes in the Kathmandu Valley generally stood, and open spaces identified in advance served as shelters. By contrast, many rural homes built of stone and mud mortar, the traditional method in the hills, collapsed completely, which is why rebuilding grants were tied to safer designs and training for local masons.

The earthquake hit Nepal’s economy hard. Tourism, a major source of income and jobs, fell sharply in 2015, trekking routes such as Langtang were closed for months, and remittances from Nepalis working abroad became even more important for families who had lost homes and livelihoods. Many of the poorest households, including those of lower castes and minority groups in remote areas, took longest to recover.

By the numbers

Timeline

• 1934, 15 January: The Nepal-Bihar earthquake devastates the Kathmandu Valley.
• 2015, 25 April, 11:56: The magnitude 7.8 Gorkha earthquake strikes; an avalanche hits Everest Base Camp.
• 2015, 12 May: A magnitude 7.3 aftershock strikes Dolakha District.
• 2015, 25 June: Donors pledge about 4.4 billion US dollars at a reconstruction conference in Kathmandu.
• 2015, 20 September: Nepal promulgates its new constitution.
• 2015, December: The National Reconstruction Authority is established.
• 2021, April: The rebuilt Dharahara tower opens.

Why it matters

The Gorkha earthquake was the deadliest disaster in Nepal’s modern history and a stark reminder of the seismic risk along the whole Himalayan arc. Like the Sichuan earthquake of 2008 and the Haiti earthquake of 2010, it showed how building quality determines death tolls, and it prompted Nepal to adopt stricter building codes and to rebuild much of its cultural heritage.