A sudden and devastating flash flood that struck the Nepal-China border earlier this week has been linked to the drainage of a supraglacial lake in Tibet, according to a detailed satellite analysis by the International Centre for Integrated Mountain Development (ICIMOD). The disaster has left at least nine people dead and more than 30 missing, highlighting growing concerns over climate-induced hazards in the Himalayan region.
The flood, which occurred on July 8, destroyed the Friendship Bridge at Tatopani, a crucial trade route between Nepal and China, and swept away dozens of trade containers from a customs yard in the area. Among the missing are 19 Nepali nationals and 11 Chinese citizens, including customs staff and workers. The Nepal Army and police have launched extensive search and rescue operations in the affected regions of Sindhupalchowk District.
ICIMOD confirmed that satellite images showed the sudden release of water from a supraglacial lake located north of Nepal’s Langtang Himal, within Tibet’s territory. This rare but increasingly frequent phenomenon, known as a glacial lake outburst flood (GLOF), is being fueled by accelerated glacial melting and permafrost collapse, driven by global warming.
This incident comes amid early and intense monsoon rains across Nepal, which have already caused deadly landslides and flash floods in multiple districts. The Ministry of Home Affairs reported that at least 38 people have died or gone missing due to monsoon-related disasters since the end of May.
Environmental experts have called the flood “completely unprecedented,” citing a troubling rise in similar events across the Hindu Kush Himalaya region in recent years. In October 2023, a glacial lake burst in India’s Sikkim state killed 55 people, while in August 2024, twin glacial lakes flooded Nepal’s Thame region, displacing numerous families.
The Bhote Koshi River, known in Tibet as the Lhende River, became the path of destruction as the floodwaters surged downstream with tremendous force, carrying debris and uprooting infrastructure. Video footage showed massive cargo containers being swept away like toys, and widespread devastation along the riverbanks.
ICIMOD and other experts have urged regional governments to strengthen early warning systems and cross-border cooperation for monitoring glacial lakes. They also stressed the need for better risk zoning, climate-resilient infrastructure, and international support to address the long-term threats posed by climate change in the fragile Himalayan ecosystem.
With climate scientists warning of continued glacier retreat and increasing precipitation variability, the recent flood serves as a stark reminder of the urgent need for coordinated action to prevent further tragedies in one of the world’s most vulnerable mountain regions.