Nepal plans to drain four glacial lakes after deadly floods

Published 2026-10-03 · Updated 2026-10-03 · 3 min · 523 words

UPSC CSE Context

Why in News

Nepal will begin draining four high-risk glacial lakes this fiscal year to reduce Glacial Lake Outburst Flood (GLOF) risks after a deadly August disaster killed over 1,400 people.

Syllabus Connection

Disaster management, climate change adaptation, Himalayan ecology, and international environmental cooperation.

Exam Relevance

Provides a current example for answers on climate-induced disasters, transboundary risk management, and sustainable mountain development in the Himalayan region.

Core Issue

Nepal's proactive GLOF risk reduction through controlled lake draining.

Key Development

Nepal will start draining four dangerous glacial lakes using gated structures, with studies beginning this fiscal year and completion expected in up to six years.

Stakeholders

• Nepal government
• Centre for Hydrology and Water Resources Research
• Green Climate Fund
• UNDP
• ICIMOD
• Downstream communities
• Hydroelectric plant operators

Static Knowledge

High-Value Background

• Glacial Lake Outburst Floods (GLOFs) occur when natural dams of moraine or ice fail, releasing huge volumes of water suddenly.
• Kush Himalaya region has over 3,000 glacial lakes, many at risk due to rising temperatures.

Exam Linkage

• Useful for questions on climate change impacts in the Himalayas and disaster risk reduction strategies.

Concepts in Context

• GLOF risk is heightened by earthquakes, avalanches, and unplanned human activity in high-altitude zones.

Dynamic Analysis

Disaster Management

• Controlled draining reduces immediate flood risk but requires long-term monitoring and maintenance.
• Early warning systems and community preparedness are critical complements to structural measures.
• High-altitude work poses health and safety risks to workers, adding operational complexity.

Climate Change Adaptation

• Nepal's negligible emissions contrast with its high vulnerability, highlighting climate justice concerns.
• Glacial retreat is accelerating, making adaptation urgent but costly for mountain nations.
• International funding is essential for scaling up such projects across the Himalayas.

International Relations

• Transboundary river systems mean Nepal's GLOF risk management has regional implications for India and Bangladesh.
• Cooperation on early warning and data sharing could enhance regional disaster resilience.

Economy

• Recent floods destroyed a dozen hydroelectric plants, impacting energy security and economic recovery.
• Nepal needs nearly $5 billion for early recovery, straining its fiscal capacity.
• Investing in prevention is more cost-effective than post-disaster reconstruction.

Prelims Takeaways

• Nepal has reported about 26 GLOF events in the past four decades.
• The four lakes targeted are Thulagi, Lower Barun, Lumding Tsho, and Hongu II, located between 4,050 m and 5,483 m.

Mains Value Addition

Arguments

• Proactive GLOF risk reduction is a model for climate adaptation in vulnerable mountain regions.
• International climate finance is indispensable for developing countries facing high adaptation costs.
• Transboundary cooperation is needed to manage shared water-related disaster risks.

Examples

• Nepal previously lowered Tsho Rolpa lake by 3 m in 2000 and Imja lake a decade ago, demonstrating technical feasibility.

Counterpoints

• Draining lakes may not eliminate risk entirely due to unpredictable triggers like earthquakes.
• Long project duration (up to six years) leaves communities exposed in the interim.

Way Forward

• Strengthen regional early warning systems and data sharing among Himalayan countries.
• Integrate GLOF risk reduction into national and local disaster management plans.
• Secure sustained international climate finance for long-term adaptation projects.
• Build community resilience through awareness, evacuation drills, and livelihood diversification.
• Conduct regular monitoring and maintenance of drained lakes and installed infrastructure.

Primary/reference source: thehindu.com