In-Depth Study Launched to Evaluate High-Risk Glacial Lakes in Sikkim

A fortnight-long study has been initiated to evaluate six high-risk glacial lakes in Sikkim. Conducted by the NDMA, it will assess lake stability and potential risks through various technologically advanced surveys. The study aims to mitigate Glacial Lake Outburst Floods (GLOFs) by reducing water volumes in glacial lakes.

A detailed fortnight-long study was initiated on Saturday to evaluate the volume, depth, and longitudinal profile of six high-risk glacial lakes in Sikkim, officials confirmed.

Organized by the National Disaster Management Authority (NDMA), the Glacial Lake Susceptibility Assessment Study (GLSAS) aims to characterize the physical dimensions of these lakes using a bathymetry survey.

The study will include a geophysical assessment of the moraine dam to evaluate its stability using Electrical Resistivity Tomography (ERT) and Ground Penetrating Radar (GPR).

The expedition in Mangan district focuses on high-risk glacial lakes like Tenchungkha, Khangchung Chho, and others. Rapid assessments of additional lakes will be conducted if time permits.

This effort includes a slope stability assessment and a morphometric survey of the glacial lakes and their landscapes. Lake discharge measurements and outlet flow dynamics will also be assessed. Additionally, drone technology will be employed for 3D terrain mapping to create a high-resolution terrain model.

Glaciers' sensitivity to climate change has resulted in widespread glacier retreat, leading to an increase in the number and area of glacial lakes. These lakes pose a significant risk of glacial lake outburst floods, which can have catastrophic impacts on lives, property, and infrastructure.

Sikkim recently experienced a glacial flood event on October 4, 2023, from the South Lhonak Glacial Lake, severely affecting lives, infrastructure, and the local ecosystem. The state has not yet recovered from its aftereffects.

Unlike other natural disasters, Glacial Lake Outburst Floods (GLOFs) can be prevented by reducing the water volume in glacial lakes through structural and non-structural measures.

The NDMA has identified 189 high-risk glacial lakes in India; 40 of these are in Sikkim alone, located in challenging terrain and severe climate conditions.

(With inputs from agencies.)