Why Nepal's glacial lakes demand Indian action
Summary
Nepal’s plan to drain four glacial lakes follows a catastrophic flood along the China-Nepal border that left more than 1,450 dead and thousands missing. The author argues that India should support Nepal with technical assistance, shared data and early-warning systems because floodwaters can cross into India. The plan covers only four of Nepal’s 21 highly dangerous glacial lakes and does not include the valley hit in August. The author also urges South Korea to support warning cooperation, citing its experience with an unannounced North Korean dam release.
Key Facts
- The four lakes named in Nepal’s six-year plan are Thulagi, Lower Barun, Lumding Tsho and Hongu-2.
- The August flood traveled from the Lhende Khola into the Bhote Koshi, then through the Trishuli and Narayani rivers before entering India as the Gandak and joining the Ganga.
- The 2008 Koshi embankment breach at Kusaha displaced more than 2.3 million people in northern Bihar.
- During the August collapse, seismic instruments registered a magnitude 5.2 shockwave, while the river gauge at Syabrubesi went offline within minutes.
- The author proposes routing Indian cooperation through the UN Development Programme and the International Centre for Integrated Mountain Development, with station ownership remaining in Nepal.

Nepal’s ambitious six-year plan to drain four high-altitude glacial lakes — Thulagi, Lower Barun, Lumding Tsho and Hongu-2 — is born of sheer urgency. Following a catastrophic flood along the China-Nepal border that left more than 1,450 dead and thousands missing, Kathmandu is scrambling to mitigate future disasters. New Delhi cannot afford to view this as a purely domestic Nepali affair. For India, providing immediate technical support, data sharing and early warning systems to Nepal is proactive flood defense for its own northern plains.
The catastrophic August deluge surged from the Lhende Khola into the Bhote Koshi, then wound through the Trishuli and Narayani rivers before crossing into India as the Gandak river to join the Ganga. The primary threat is rarely a sudden wall of water but rather an acute, destabilizing volume surge delivered to rivers already swollen by monsoons and hemmed in by fragile embankments. The 2008 Koshi embankment breach at Kusaha permanently altered the river's course, displacing over 2.3 million people in northern Bihar.
The current project addresses only four of Nepal's 21 highly dangerous glacial lakes, leaving the exact valley that experienced flooding in August completely untouched. Where engineering fails, technology must step in. When the August collapse occurred, seismic instruments registered the shockwave as a magnitude 5.2 event. Linked to automated alerts, such data can buy downstream communities precious minutes — provided the monitoring systems are properly maintained.
However, technology requires infrastructure and upkeep. Automated monitoring stations, lake-level sensors and satellite feeds are remarkably inexpensive when measured against the catastrophic cost of a breached levee. Facing a $5 billion recovery bill, Nepal cannot secure its mountains alone, but India is noticeably absent from the project's current list of financial backers. This is a missed diplomatic and security opportunity. India already possesses world-class satellite arrays, meteorological assets and a Central Water Commission that tracks these very river systems. Sharing this existing data costs New Delhi virtually nothing.
The 1954 Koshi Agreement remains a point of friction in Nepal, and any unilateral Indian offer to plant equipment in Nepali mountains will be viewed with skepticism. New Delhi should route its cooperation through multilateral bodies like the UN Development Programme and the International Centre for Integrated Mountain Development, the Kathmandu-based mountain center where India holds a seat. By ensuring data flows symmetrically and leaving station ownership with Nepal, India can build trust.
South Korea knows what an unwarned flood looks like. In 2009, North Korea released water from the Hwanggang Dam without notice, and six South Koreans were swept away in the resulting flooding on the Imjin River. Seoul has an interest here beyond sympathy. The Green Climate Fund is based in Incheon, the Korea International Cooperation Agency runs aid programs in Nepal and thousands of Nepali workers live in Korea. Sensors and gauges would be cheap, and Seoul's own experience with an upstream neighbor gives it standing to press for data sharing.
Early warning cooperation is a rare geopolitical arena where one nation's gain does not equal another's loss. During the August disaster, the river gauge at Syabrubesi went offline within minutes of the glacial collapse. A sensor's sudden silence is a loud distress signal — but only if someone downstream is listening. India's major rivers begin in foreign peaks; its domestic security is hostage to what happens in those mountains and how fast that information reaches Delhi and Patna. The next deluge will not pause at the border. The only remaining question is whether India chooses to hear it coming.
Brabim Karki is a businessman and writer based in Nepal. The views here are his own.
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