Ice-rock avalanche may have triggered Nepal flash flood, say scientists

An ice-rock avalanche may have been the catalyst for a devastating flash flood in Nepal, according to scientists from the International Centre for Integrated Mountain Development (ICIMOD). The flood occurred in the Rasuwa district, located downstream of Tibet, causing water, sediment, and boulders to flow through the Bhote Koshi and Trishuli rivers.

Preliminary assessments based on video footage and information from the affected areas suggest that a significant amount of ice and rock debris entered the Lende Khola, a tributary of the Bhote Koshi river. This event could have generated a sudden surge, carrying water, sediment, and large boulders downstream. Qianggong Zhang, Head of Climate and Environmental Risks at ICIMOD, noted that an ice avalanche in the Lhende Khola is currently the suspected trigger, but the cause remains unconfirmed.

Authorities are warning of a potential second flood due to a blockage still present upstream on the Nepal-China border. Experts are currently assessing the situation, including the possibility of a landslide dam that could create a secondary hazard if the impounded water is suddenly released.