Sikkim Chief Secretary chairs high-level meeting on GLOF preparedness and risk mitigation

Sikkim Chief Secretary R. Telang chaired a high-level coordination meeting at the Tashiling Secretariat to review preparedness and ongoing measures to mitigate the risks associated with potential Glacial Lake Outburst Floods (GLOFs) in the state.

The meeting brought together representatives from state departments, central agencies, defence organisations, technical institutions and project developers to assess scientific studies, early warning systems, mitigation measures and inter-agency coordination for strengthening GLOF preparedness.

The Department of Science and Technology highlighted the significant losses suffered by Sikkim during the 2023 South Lhonak Lake GLOF and outlined measures to strengthen preparedness against future glacial flood events. These include establishing and strengthening early warning systems, developing resilient infrastructure, protecting critical roads, dams, bridges and habitations, and preparing site-specific mitigation proposals.

The department also discussed scientific studies involving hydrometeorological assessments, Electrical Resistivity Tomography, bathymetric investigations, hydrological and geological studies, and UAV-based terrain mapping. Plans were also outlined for hydrodynamic modelling, refinement of GLOF propagation scenarios and preparation of structural mitigation measures.

Particular attention was given to Shako Chho Lake, identified as one of Sikkim’s 16 Category A high-risk glacial lakes. The lake has no natural outlet and is characterised by an unstable configuration and a permeable moraine dam. The nearest habitation, Thangu village, is around 13 km downstream, making timely intervention important. Solar-powered pumps have been identified as a practical option for lowering the lake level, while structural intervention has not been considered advisable and a siphon system was assessed as unfeasible.

For the Gurudongmar Complex, a moraine plug-wall mitigation strategy has been proposed, while for the Lhonak Complex, a Preliminary Project Report has been submitted to the Ministry of Jal Shakti. The Central Water Commission and Sikkim’s Department of Science and Technology are also working on a Detailed Project Report for a flood-retention structure at Dolma Sampa near Muguthang.

The Central Water Commission presented updates on glacial lake monitoring, flow-path mapping, early warning systems, hydrological monitoring and flood forecasting. The Geological Survey of India presented a comprehensive multi-hazard risk analysis along the Teesta River corridor from Zema to Meli, covering flood dynamics, GLOF-related hazards, slope stability and seismic vulnerability.

The meeting also reviewed GLOF preparedness measures by NHPC and Greenko, including early warning systems, risk assessment, monitoring, reservoir management and safety measures associated with hydroelectric projects in the Teesta and Rangit basins.

Relief Commissioner-cum-Secretary Rinzing Chewang Bhutia highlighted community sensitisation programmes and vulnerability mapping undertaken by the Sikkim State Disaster Management Authority. Professors from Sikkim University stressed the need for updated scientific assessments of high-risk glacial lakes, high-resolution ground data, drone-based mapping and improved modelling of debris flows and other downstream hazards.

Chief Secretary Telang stressed that Early Warning Systems must be efficient, reliable and capable of disseminating alerts at the earliest possible stage. He also called for regular mock exercises and preparedness drills to strengthen institutional coordination, response capacity and community readiness in the event of a GLOF or related disaster.

He further emphasised close coordination among scientific institutions, technical agencies, state departments, project developers, defence organisations and local administrations to address the evolving risks associated with glacial hazards.