Glacial Lake Outburst Floods (GLOFs) in Nepal: History, Current Crisis, and Future
Summary
Nepal’s Himalayan region faces rising glacial lake outburst flood risks as melting glaciers, unstable moraines, and avalanche-triggered floods threaten downstream communities and infrastructure. Past disasters in Imja, Dig Tsho, Tam Pokhari, and transboundary events in Tibet and India show the danger is growing more complex and more destructive.
Key Points
- Nepal has recorded multiple GLOF events since the 1930s, including major incidents at Imja, Dig Tsho, Tam Pokhari, and transboundary flood events from Tibet and Sikkim.
- Climate change is accelerating glacier melt, expanding glacial lakes and increasing the likelihood of avalanches, rockfalls, debris flows, and sudden lake bursts.
- ICIMOD, UNDP, and the Government of Nepal have supported risk reduction efforts such as lowering Imja Lake and assessing high-risk lakes like Tsho Rolpa, Lower Barun, and Thulagi.
- The 2025 Bhote Koshi flood and the 2026 Rasuwa-Tibet tragedy highlight that Himalayan disasters are increasingly transboundary and may involve glacier collapse, not just glacial lake bursts.
