Archive · 4 Sep 2026
Sikkim Identifies 40 High-Hazard Glacial Lakes, 16 Highest-Risk
Sikkim has found 40 glacial lakes that could become dangerous.
Sixteen of them are in the highest-risk group.
A glacial lake outburst flood happens when a lake suddenly releases a large amount of water.
The water can carry mud and debris into places downstream.
Sikkim suffered a deadly GLOF in 2023 that killed at least 60 people.
Officials are watching the lakes with satellites and scientific surveys.
They are also studying ways to lower lake levels and hold back floodwater.
Shako Chho has been named the most vulnerable lake.
The state is proposing more warning sensors and a special safety protocol.
Sikkim identified 40 high-hazard glacial lakes, including 16 in the highest-risk Category A.
Two lakes are in Category B, nine in Category C, and 13 remain unclassified.
Officials are using satellite imagery, remote sensing, field surveys and flood modelling to assess risks.
Shako Chho was identified as the most vulnerable lake, with mitigation reports submitted to national authorities.
The measures follow Sikkim’s October 2023 GLOF, which killed at least 60 people and destroyed the Chungthang dam.
- Who
- The Sikkim government, its Department of Science and Technology, and national agencies including the National Disaster Management Authority and Central Water Commission.
- What
- Officials identified 40 high-hazard glacial lakes, with 16 classified as Category A, the highest-risk level.
- When
- The findings were presented at a GLOF-risk workshop on Thursday; the Department of Science and Technology became the nodal department in February 2025.
- Where
- Sikkim, in India’s eastern Himalayas.
- Why
- Retreating glaciers are creating new lakes and enlarging existing ones, increasing potential risks to downstream communities.
- High-hazard lakes
- 40 identified in Sikkim
- Highest-risk lakes
- 16 are classified as Category A
- Other classifications
- Two are Category B, nine are Category C, and 13 remain unclassified
- Most vulnerable lake
- Shako Chho
- Previous GLOF
- Sikkim’s October 2023 outburst killed at least 60 people and destroyed the Chungthang dam
- Monitoring methods
- Remote sensing, satellite imagery, water-level and discharge monitoring, geophysical surveys, bathymetry and flood modelling
- Planned mitigation
- A dedicated GLOF Risk Mitigation Protocol, additional early-warning sensors and lake-specific engineering measures
