Sikkim to embark on scientific expedition to study 5 glacial lakes

Amitava Banerjee, MP, 25 Aug 2024, Darjeeling: The National Disaster Management Authority (NDMA) has identified 16 high altitude glacial lakes in Sikkim as highly vulnerable. Sikkim will be conducting a scientific expedition to study 5 such vulnerable glacial lakes in the Mangan district. 

This comes in the wake of a Glacial Lake Outburst Flood (GLOF) in lake South Lhonak causing widespread damage along the Teesta River in Sikkim and contiguous areas of Bengal on the intervening night of October 3- 4, 2023. 

The lakes to be studied include Gurudongmar A, B, C, Sako Chu and Khang Chu, all located on the Indo-Tibetan border in the state of Sikkim. The expedition pegged at a cost of Rs 32 lakh will commence on August 28 till September 14. 

“This is the right time to conduct such an expedition as it cannot be done once the harsh winter sets in. We have decided on a holistic, integrated approach with different departments involved in this joining expedition, including the State Science and Technology; State Disaster Management Authority (SDMA); Mines and Geology; Water Resources, Forest along with Sikkim University. 

Logistics support will be provided by the Indian Army and the Indo-Tibetan Border Police,” stated Namrata Thapa, State Relief Commissioner, Sikkim. The team of 56 persons, including 32 experts, will be led by Sandeep Tambe, Secretary, State Science and Technology department. 

Addressing a press conference in Gangtok, Tambey stated: “Along with accessing the 5 lakes and studying the vulnerability of these lakes, we will focus on mitigation of glacial hazards; threat of floods and stability of moraine dams formed by glaciers.” 

Moraine-dammed lakes are natural freshwater lakes dammed by material accumulated from a glacier (termed as moraine). The mitigation plans to reduce water level (to prevent outbursts) will include siphoning, pumping, tunneling, channeling and reshaping the bed of the lake. 

“We will also test the strength of the moraine dams and equipment to monitor water levels. If successful other mountain states can replicate this,” added the Secretary.Each of the departments have been entrusted with some specialised tasks. 

The Mines and Geology department will conduct geophysical investigation and will conduct electrical resistivity tests along with ground penetrating radar surveys. Studies will be conducted of water catchment areas and vulnerable areas. 

SDMA will undertake hazard mapping using satellite imagery to identify highly vulnerable areas at risk of GLOF. 

3 other lakes in the Geyzing district of West Sikkim and 13 in the Mangan district of Sikkim are highly vulnerable. Before the 2023 GLOF at South Lhonak lake in Sikkim, the NDMA and Swiss experts had undertaken a similar expedition. 

An automatic weather station is already set up at Sako Chu, sending real time data. A special task force has been constituted by the SDMA which shares important data with neighbouring Nepal, Bhutan, UNDP and Swiss experts. 

The Science and Technology department had also completed a two-week scientific expedition to the East Rathong Glacier, conducted from June 22 to July 4 this year. The expedition was part of the department’s ongoing study on glacier dynamics and the assessment of potential glacial lake outburst flood (GLOF) risks. 

“The study reports of that expedition are being prepared and will be made public following the approval of the government,” added Namrata Thapa. According to the National Emergency Response Centre of India (NDMI), in the October 2023 Teesta disaster, there were over 100 deaths and over 70 missing individuals. Around 4,500 were evacuated. 

Around 90,000 people were affected. Additionally, about 2 000 houses were damaged. 

Courtesy & source- Millennium Post