Climate change escalates risk from Sikkim's Glacial lakes, warns DST Principal Director

Rapid climate change is escalating the risks posed by Sikkim's glacial lakes, according to Dhiren Shresta, Principal Director of the Department of Science and Technology (DST). Speaking at the State Disaster Risk Reduction Day, Shresta highlighted the use of satellite data to monitor these lakes, particularly in Sikkim's north and west districts.

The number and size of high-altitude lakes in the region have significantly increased due to global warming. Shresta warned that by 2045, Sikkim's minimum temperature could rise by 1.5 to 2 degrees Celsius, accelerating glacial melt.

Satellite data has revealed 789 lakes covering 3,304 hectares in Sikkim. The recent glacial lake outburst flood (GLOF) at South Lhonak Lake discharged over 30 million cubic metres of water, equivalent to five large dams, causing significant downstream damage.

In response, the state government has formed a GLOF hazard commission led by Professor Akhilesh Gupta and a high-level steering committee chaired by the Chief Secretary to oversee monitoring and mitigation efforts.

The DST has identified 16 high-risk lakes in Sikkim, with three in Gyalshing district and 13 in Mangan district. Preliminary assessments have been completed, and field studies are ongoing to evaluate potential GLOF threats.

Shako Cho, one of the most vulnerable lakes at 4,990 meters altitude, holds 27 million cubic meters of water and lacks a clear outlet, posing a significant risk to downstream villages like Thangu.

Mitigation measures under consideration include lake-level lowering, solar-powered pumps, and check dam construction. The DST is collaborating with local stakeholders, the Indian Army, and academic institutions, while also studying global best practices from countries like Peru, Bhutan, and Nepal.

A detailed report with recommendations for long-term GLOF risk mitigation in Sikkim will be submitted by the DST, Water Resources Department, and Sikkim State Disaster Management Authority. However, Shresta cautioned that the threat of further GLOF incidents persists due to ongoing glacial melting.