High-Mountain Hazards in the Indian Himalaya: An Assessment of the Causes and Effects of the Chamoli Flood in 2021

Keywords: Chamoli Flood, Natural Hazards, Ice Rock Avalanches, Hydropower Projects, High-Mountain Asia
Session Type: Virtual Poster Abstract
Day: Saturday
Session Start / End Time: 2/26/2022 03:40 PM (Eastern Time (US & Canada)) - 2/26/2022 05:00 PM (Eastern Time (US & Canada))
Room: Virtual 6

Abstract

A devastating flood severely impacted the Ronti Gad, Rishiganga, and Dhauliganga River Valleys in the northwestern District of Chamoli, India, on February 7, 2021. The flood washed away two hydropower projects and caused more than 200 fatalities. In this study, some of the causes and effects of the flood were assessed. The analysis of precipitation and temperature data, satellite imagery, qualitative data, as well as digital elevation model (DEM) differencing has shown that an ice rock avalanche was released as a result of a bedrock failure underneath the hanging glacier on Ronti Peak. The ice rock avalanche quickly transformed into a flood and caused widespread devastation. GIS analyses revealed an approximate detachment volume of 26.2 Million m3 of ice and rock. The disaster sparked further discussion of hydropower project developments and highlights the importance of adequate early warning systems in fragile high-mountain systems.