Nepal plans controlled drainage at four high-risk glacial lakes as GLOF adaptation accelerates

Nepal is moving ahead with a programme to reduce the risk from four high-altitude glacial lakes: Thulagi, Lower Barun, Lumding Tsho and Hongu 2. Reuters reported on 2 October that the government plans controlled drainage works as part of a wider adaptation programme.

The underlying project is backed by the Green Climate Fund and implemented with UNDP and Nepal’s Department of Hydrology and Meteorology. Official project documents include lake-level reduction, expanded monitoring and early warning, protective works and community preparedness. The total project value is about $49.9 million, with a GCF grant of roughly $36.2 million.

A glacial lake outburst flood can occur when a natural moraine or ice dam fails, suddenly releasing stored water. Climate-driven glacier retreat can expand unstable lakes, but each lake has its own geomorphology and risk profile. Drainage itself must therefore be carefully engineered because structural failure during intervention can create additional danger.

For civil-services preparation, the programme is a Himalayan climate-adaptation case study relevant to India as well as Nepal. Mountain hazards cross political borders through river systems, infrastructure and shared climate exposure. Preventive engineering, early warning and community preparedness are complementary rather than interchangeable tools.