Kathmandu [Nepal], October 11 – A landslide that temporarily blocked a river or its tributary is suspected to have triggered a sudden flood in the Budhi Gandaki River in Gorkha district on Sunday although the exact cause remains unconfirmed.
Authorities have launched a technical investigation to determine where the landslide occurred and how the river may have been blocked before the accumulated water surged downstream.
According to the Flood Forecasting Section, the affected area received only scattered rainfall in the preceding 24 hours making heavy rainfall an unlikely immediate trigger.
The National Disaster Risk Reduction and Management Authority has deployed a three-member team of geologists equipped with drones to examine the terrain, possible landslide sites and locations where the river may have been obstructed.
Climate and environmental expert Ujjwal Upadhyay said preliminary information suggested that a tributary rather than the main river source could have generated the flood.
At the Arughat monitoring station the river level rose from 2.28 metres at 6:30 am to 8.43 metres by 8:40 am. The flood subsequently swept away the monitoring station preventing further measurements.
Five people have been reported missing from Chumchet in Chumanubri Rural Municipality. Authorities are continuing to assess the damage and investigate the cause of the disaster.
Experts have called for stronger river monitoring, landslide surveillance, warning sirens and community-based alert systems to reduce risks in vulnerable Himalayan settlements.
