GLOF threaten Himalayan region and demand action

Source: The post GLOF threaten Himalayan region and demand action has been created, based on the article “How is India preparing against GLOF events?” published in “The Hindu” on 28th July 2025

UPSC Syllabus Topic: GS Paper 1- Important Geophysical phenomena.

Context: On July 8, Nepal faced a major Glacial Lake Outburst Flood (GLOF) triggered by a burst in a supra-glacial lake in Tibet. This event destroyed a China-built bridge and disrupted power supply in Nepal. With rising temperatures and increasing GLOFs, the need for early warning systems and regional collaboration is urgent.

Rising GLOF Incidents and Their Impact on Nepal

1. Recent GLOFs and Infrastructure Damage: A GLOF event on July 8 caused a flash flood along the Lende river, destroying a China-built bridge and damaging Nepal’s inland port at Rasuwagadhi. Four hydropower plants were rendered unusable, cutting off 8% of Nepal’s power.
2. Lack of Early Warning and Coordination: Nepalese officials reported no prior warning from Chinese authorities. Despite visible surface shrinkage of the Tibetan lake, no alert system exists across the border.
3. Recurring GLOF Events Across Nepal: Another GLOF occurred in Mustang district the same day. Earlier events were recorded in Humla (two GLOFs in 2024) and Solukhumbu (destruction of Thame village), highlighting the recurring nature of these disasters.
4. Past Events and Mitigation Measures: GLOFs in 1981, 1985, and 1998 showed the region’s long-standing vulnerability. Nepal has worked to reduce water levels in high-risk lakes like Imja Tsho and Tsho Rolpa, though these efforts are extremely challenging due to terrain and altitude.

India’s GLOF Risk Landscape

1. Types of High-Risk Lakes in the IHR: India’s Himalayan region hosts 28,000 glacial lakes, mainly supraglacial and moraine-dammed types. These are vulnerable to meltwater pressure, avalanches, landslides, and earthquakes.
2. Environmental Conditions Raising Risk: With 2023 and 2024 being the hottest years, glacial melt has intensified. Over 7,500 Indian glacial lakes lie above 4,500 m, limiting monitoring to short summer periods.
3. Challenges in Monitoring and Early Detection: Due to inaccessibility and cost, weather and water stations are mostly absent. Remote sensing gives only surface change data, offering limited predictive value.
4. Impacts of Past GLOFs in India: The 2023 South Lhonak GLOF destroyed the Chungthang dam and caused silting, raising the Teesta riverbed. The 2013 Chorabari GLOF in Kedarnath led to massive fatalities and infrastructure loss.

India’s Strategic Response to GLOF Threat

1. Shift to Risk Reduction Strategy: India’s NDMA shifted from reactive response to proactive risk mitigation under the Committee on Disaster Risk Reduction (CoDRR), involving central and state agencies.
2. National Programme and Scaling Plans: A $20 million national programme identified 56 high-risk lakes, now expanded to 195. Scaling is planned post-16th Finance Commission’s award (FY2027–31).
3. Five-Fold Programme Objectives: The strategy includes: risk assessment, installing AWWS, building early warning systems, drawing down water levels, and ensuring local community involvement.
4. Use of Advanced Technologies: Indian technologies like SAR interferometry (detecting micro slope changes) were promoted, but their broader application remains limited and urgently needed.

Implementation and Ground-Level Challenges

1. Successes and Challenges in Field Expeditions: Expeditions across Himalayan states conducted lake depth mapping, ice-core detection, and UAV-based surveys. Incidents of weather delays and cultural sensitivity highlighted local integration needs.
2. Installation of Monitoring Systems: Lakes in Sikkim now have stations sending 10-minute interval data and daily lake images. More such systems are planned, aiming to bridge critical data gaps.
3. Community Engagement and Manual Alert Systems: Community involvement proved essential for access and credibility. In the absence of automated alerts, the Indo-Tibetan Border Police have been tasked with manual early warnings.
4. Future Roadmap for GLOF Management: States are preparing for further expeditions post-monsoon, with a focus on sustained monitoring, enhanced technology deployment, and stronger inter-agency coordination.

Question for practice:

Discuss the growing threat of Glacial Lake Outburst Floods (GLOFs) in the Himalayan region and the measures taken by Nepal and India to mitigate their impact.