A catastrophic flood along the Nepal-Tibet border has killed more than 390 people and left over 1,400 missing after a massive glacier collapse high in the Himalayas unleashed a torrent of water, ice, rock and mud through mountain valleys and settlements.Rescue operations are continuing across remote areas where roads, bridges, buildings and power infrastructure have been destroyed, leaving thousands of people cut off and forcing authorities to rely heavily on helicopters.According to the latest figures from Nepalese authorities, at least 389 people have died in Nepal, more than 460 have been injured and around 910 remain missing. Authorities in China’s Tibet Autonomous Region have confirmed three additional deaths, while 558 people are still unaccounted for.Hundreds of foreign nationals are among the missing. Nepal’s tourism authorities say more than 500 foreigners have not yet been accounted for, while Chinese authorities report that approximately 260 of those missing on the Tibetan side are foreign nationals.
Many of those caught in the disaster were tourists or pilgrims travelling through the region towards Mount Kailash and Lake Manasarovar, sacred destinations visited by followers of several religions.Some of the worst destruction has occurred along the Lhende, Bhote Koshi and Trishuli river systems. Researchers reported that water levels in parts of the affected area rose by as much as nine metres in around 30 minutes, giving communities downstream almost no time to escape.Initial reports suggested that a magnitude 4.4 earthquake may have triggered the disaster. The United States Geological Survey later revised its assessment, concluding that the seismic signal was most likely generated by the glacier collapse itself. The event was subsequently assessed as producing a seismic signal of approximately magnitude 5.2.
Preliminary scientific analysis indicates that a large section of glacier broke away at high altitude and plunged into the valley below, gathering rock and sediment as it moved downhill. Scientists are also investigating whether the debris temporarily blocked a river before the natural dam failed, releasing an enormous surge of water and debris downstream.Military and civilian helicopters are being used to search for survivors, evacuate injured residents and deliver emergency supplies. Dozens of bridges and significant sections of road have been destroyed or damaged, severely restricting access to some of the hardest-hit communities.Thousands of military personnel, police officers and emergency workers have been deployed. Aid including food, drinking water, tents and medicines is being transported into isolated areas while hospitals in Kathmandu and other cities receive the injured.
Authorities are also warning that the immediate danger has not passed. Newly formed or rapidly expanding bodies of water in the mountains are being closely monitored because another natural dam failure could trigger further flooding and landslides. Villages considered particularly vulnerable have been evacuated.The disaster has also renewed concern over the growing instability of the Himalayan cryosphere. Scientists caution that it is still too early to attribute this individual event directly to climate change. However, rising temperatures are accelerating glacier retreat, thawing permafrost and destabilising steep mountain slopes throughout the Hindu Kush-Himalayan region.Those changes can increase the risk of glacier collapses, landslides, glacial lake outburst floods and cascading disasters in which one event rapidly triggers another.Search and rescue operations remain under way, and officials warn that casualty figures could continue to change as emergency teams reach valleys and settlements that have remained inaccessible since the disaster.
