Transboundary hazard and downstream impact of glacial lakes in Hindu-Kush Karakoram Himalayas

Saket Dubey; Ashim Sattar; Vivek Gupta; Manish Kumar Goyal; Umesh K Haritashya; Jeffrey S Kargel

doi:10.1016/j.scitotenv.2023.169758

Transboundary hazard and downstream impact of glacial lakes in Hindu-Kush Karakoram Himalayas

Sci Total Environ. 2024 Mar 1:914:169758. doi: 10.1016/j.scitotenv.2023.169758. Epub 2024 Jan 1.

Authors

Saket Dubey¹, Ashim Sattar², Vivek Gupta³, Manish Kumar Goyal³, Umesh K Haritashya⁴, Jeffrey S Kargel⁵

Affiliations

¹ School of Infrastructure, Indian Institute of Technology Bhubaneswar, India; Department of Geology and Environmental Geosciences, University of Dayton, Dayton, OH, USA. Electronic address: saketdubey4@gmail.com.
² School of Earth, Ocean and Climate Sciences, Indian Institute of Technology Bhubaneswar, India.
³ Department of Civil Engineering, India Institute of Technology, Indore, India.
⁴ Department of Geology and Environmental Geosciences, University of Dayton, Dayton, OH, USA.
⁵ Planetary Science Institute, Tucson, AZ, USA.

PMID: 38171458
DOI: 10.1016/j.scitotenv.2023.169758

Abstract

Glacial Lake Outburst Floods (GLOFs) can generate catastrophic flash floods when the damming structure is breached or overtopped. Some of these glacial lakes are located in transboundary regions where floods originating from the lake in one country could inundate a neighboring country, devastating the population and infrastructure of both nations and influencing socio-political relationships. Therefore, assessing the lakes' hazard is crucial. This study investigates transboundary glacial lakes, considering their GLOF hazard, including potential mass movement intrusion, moraine's stability, upstream and downstream process cascades, downstream flood extents, and the exposure and vulnerability of the downstream infrastructure and affected population. GLOF exposure assessments were carried out to identify exposed buildings, bridges, and hydropower systems in transboundary regions. China currently has the highest number of transboundary lakes, with most of them potentially impacting India and Nepal. Most of the transboundary lakes in China, and many in India and Nepal, are susceptible to mass movements. Among the 230 transboundary glacial lakes in the Hindu Kush Karakoram Himalaya, 55 lakes can potentially impact other glacial lakes along their flow path, creating a cascade of events. Five transboundary lakes could potentially impact over 1000 buildings, and 16 lakes could impact over 500 buildings. A total of 35 lakes can impact at least one hydropower station along their flow path, and 4 lakes can impact two hydropower stations. This research emphasizes the critical importance of conducting comprehensive risk analyses of GLOFs in transboundary regions to inform policy-makers. It calls for investing in broad-scale assessments and data-driven decision-making for mitigating and adapting to GLOF risks effectively. Finally, by raising awareness among policy-makers, the study aims to drive actions that safeguard communities and infrastructure vulnerable to GLOF.

Keywords: Glacial Lake Outburst Flood (GLOF); Hindu Kush Karakoram Himalaya; Mass movement; Transboundary Hazard.