The early hours of Tuesday in 2025 saw devastating floods along the Bhotekoshi river in Rasuwa district of Nepal. The floods claimed at least nine lives and left 19 people missing. These floods were unusual as there was no rainfall recorded in the region before the event. The Nepal-China Friendship Bridge, a key trade link, was destroyed, halting cross-border trade. Rescue operations were launched immediately by Nepal’s police and army. Scientists and officials are investigating the cause of the floods, with early indications pointing away from rainfall.
Unprecedented Flooding Without Rain
The floods occurred despite no rain forecasts or warnings. Satellite data confirmed no rainfall in Tibet, the river’s upstream region. This ruled out typical monsoon-induced flooding. Experts suspect a Glacial Lake Outburst Flood (GLOF) or a landslide lake outburst but have yet to confirm. Such floods happen when a glacial lake suddenly releases water, often triggered by melting glaciers or landslides.
Vulnerability of Nepal’s Mountain Terrain
Nepal’s mountainous landscape is prone to floods, landslides, and avalanches, especially during monsoon season. Climate change has increased the frequency and severity of these disasters. Glacial lakes in the region have grown by 33% in size and 16% in number over the past three decades. Nearly 50 glacial lakes in Nepal, Tibet, and India are considered potentially dangerous, requiring close monitoring.
Challenges in Disaster Forecasting and Response
Nepal lacks effective early warning systems for sudden floods like GLOFs. There is no established mechanism for sharing flood-related information between Nepal and China. Local knowledge and scientific understanding are often underutilised in disaster preparedness. Unregulated construction and hydropower projects in the Himalayas may worsen flood risks. Experts call for integrated studies combining local data and scientific research.
Impact on Trade and Infrastructure
The flood destroyed the Nepal-China Friendship Bridge, disrupting trade at Nepal’s second-largest border crossing with China. Several cargo trucks and electric vehicles were washed away. Damage was also reported to a customs port and a hydropower dam. The border point, reopened in April 2023 after COVID-19 closures, now remains closed indefinitely. This disrupts supply chains and affects Nepal’s economy.
Climate Change and Melting Glaciers
Rising temperatures are causing Himalayan glaciers to melt twice as fast as the global average. This accelerates the risk of sudden floods. The monsoon is reaching higher altitudes, increasing hazards in mountain regions. Melting glaciers could have caused the sudden flood in Rasuwa. Experts urge urgent comprehensive studies to better understand and mitigate these risks.
Questions for UPSC:
- Discuss the impact of climate change on Himalayan glacial lakes and the associated risks of Glacial Lake Outburst Floods (GLOFs) with examples from South Asia.
- Critically examine the challenges of cross-border disaster management and information sharing between neighbouring countries, with reference to Nepal and China.
- Explain the role of local knowledge and scientific research in improving disaster preparedness in mountainous regions. How can these approaches be integrated effectively?
- With suitable examples, discuss the economic and infrastructural impacts of natural disasters on international trade routes and border regions.
