Mount Everest Foundation
Supporting the exploratory

Understanding Glacier Lake Outburst Flood (GLOF) Hazard Evolution in Lunana, Bhutan

The pair used a multi-beam echo sounder drone boat from Newcastle University to assess the bathymetry of Thorthormi lake. Launching from two locations at both ends of Thorthormi lake, they covered 15 km of the lake bed, measuring a maximum depth of 95m and covering around 30% of the lake area. Once the results are fully processed, the data will be used to estimate lake volume of this potentially hazardous glacial lake in order to inform understanding of the Glacial Lake Outburst Flood (GLOF) risk in the region. In addition to the bathymetric work, they also conducted a drone survey of all four of the area's glacial lakes, with particular focus on the moving slopes that they believe to be at risk of sliding into the lakes, and set up three new time-lapse and water level monitoring sites in order to track river level change on a seasonal scale and to test a new monitoring set up to detect a flood event in order to issue and advance warning.

May - June 2025
Sonam Rinzin and Alex Hyde

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