What caused catastrophic floods in Nepal? US monitor points to 'glacial collapse' not quake
PTC News Desk: Massive floods in a border area of Nepal and China killed over 150 people and left hundreds of tourists, workers including 133 Indians missing on Wednesday. Rescuers on Thursday raced to locate the hundreds missing, including nationals from India, the US, UK, Australia and Canada.
Meanwhile, the US Geological Survey said that a glacial collapse triggered the catastrophic flash flood in Nepal and Tibet that roared down valleys, wiping out entire villages and leaving a trail of destruction.
The US Geological Survey (USGS) initially reported that a magnitude 4.4 earthquake had struck early Wednesday, around 66 km (41 miles) north of Kathmandu near the Nepal-Tibet border. However, it later changed its assessment, saying the seismic activity was caused by a large glacial collapse rather than an earthquake.
According to the USGS, the collapse involved ice and rocks that moved downstream, triggering a massive debris flow and devastating floods. The agency based its conclusion on information from nearby seismic stations, long-period seismic waves and satellite images. It confirmed that no earthquake had occurred.
“The Lhende Khola has flooded twice in 14 months, this time triggered by an ice rock avalanche from a glacier on the Nepal side that blocked the river and released a sudden surge downstream,” Saswata Sanyal, a disaster risk reduction specialist at the climate research group was quoted as saying by news agency Associated Press (AP).
Catastrophic floods ravage Nepal
The floods hit Nepal’s Rasuwa district, which borders Tibet, on Wednesday. Villages were flooded and important infrastructure was damaged. Nepal’s Tourism Ministry said 468 tourists and travellers, including 393 foreigners, were still unaccounted for in the mountainous region, which is popular among trekkers and pilgrims.
Chinese state media reported that 558 people were missing on the Tibet side of the border, including at least 260 foreign nationals. The missing foreigners in Nepal included 142 Indians, 47 Americans, 34 Australians, 33 Britons and 24 Canadians. Nepal Police said 165 bodies had been recovered by Wednesday evening, while Chinese state media reported three deaths on the Tibet side.
Many of those affected were travelling to Kailash Mansarovar, a high-altitude pilgrimage site in Tibet that is considered sacred by Hindus, Buddhists and other religious communities.
Earlier, Nepali officials believed that an earthquake may have caused part of a glacier to collapse and trigger the floods. However, the USGS later clarified that the seismic signal was produced by the collapse of glacial rock and ice and the movement of debris, not by an earthquake.
An early analysis of Planet Labs satellite images suggested that an ice-and-rock landslide caused the debris-filled flood in the Lhende River. The incident occurred around 20 km (12 miles) northeast of the Rasuwagadhi border crossing between Nepal and China.
Experts said the steep and difficult terrain of the Himalayas increases the risk of such landslides, glacial collapses and sudden floods.
- With inputs from agencies
