Rasuwa flood likely caused by ice-rock fall, not glacial lake outburst

The catastrophic flood that recently inundated the Rasuwa district and surged along the Trishuli River in Nepal was likely triggered by a massive ice-rock landslide, according to water resources and climate change expert Santosh Nepal. This assessment challenges the initial assumption that the disaster stemmed from a glacial lake outburst.

Nepal, who holds a PhD in his field, pointed to the Langtang Lirung area as the probable source of the event. His analysis suggests that a significant collapse of ice and rock from the mountain face initiated the devastating flow of water and debris that swept through the region.

This distinction in cause is crucial for understanding flood dynamics in the Himalayas. While glacial lake outburst floods (GLOFs) are a known hazard, identifying landslides as the trigger offers different insights into the geological and climatic factors at play. Further investigation will be needed to confirm the exact sequence of events that led to the flood.

The flood caused significant devastation in Rasuwa and along the Trishuli River, impacting communities and infrastructure. Understanding the precise cause is vital for developing effective early warning systems and mitigation strategies for future events in this geologically active and climate-vulnerable region.