As a part of the national survey to preempt the Glacial Lake Outburst Flood (GLOF), the National Disaster Management Authority (NDMA) has started surveying the Eastern Himalayas to map all glacial lakes in the country and assess the feasibility of installing early warning sensors and other mitigation measures. The agency is conducting surveys in Arunachal Pradesh and Sikkim, the two important areas of the Eastern Himalayas along the China border.

Expert teams have fanned out to carry out a survey-cum-study at six high-risk glacial lakes in Tawang and Dibang Valley districts in Arunachal Pradesh, which shares a 1,080 km-long border with China. There are reports of the washing away of more than five bridges due to a glacial lake outburst from Sangnga Nehgu Lake in the Tawang district. It is also the first such survey of glacial lakes in the border state.

Sikkim has also sent an expedition of 32 experts to five under-threat glacial lakes – Gurudongmar A, B, and C, Sakho Chu, and Khangchu, all in the Mangan district, which borders Tibet.

The experts will survey the lakes from August 28 to September 14 at an estimated cost of Rs 32 lakh.

The expedition is being led by State Science and Technology Secretary Sandeep Tambe along with experts from six different departments of the State Disaster Management Authority (SDMA) under the Land Revenue Department, Mines and Geology, Water Resources, Forest, Science and Technology and research scholars from Sikkim University.

The expedition will also be aided by the Indian Army and Indo-Tibetan Border Police (ITBP) with a collective manpower of 56 individuals including drivers and porters…

“We are going to do very hi-tech studies to understand the geology of the glacial lake, understand the glacial behaviours, study the slope stability and probabilities of avalanches and GLOF. This will be a study at an altitude of 18,000 feet. Once our study is done, we will plan the mitigation plan,” said Sandeep Tambe, Secretary of the Science and Technology Department, Sikkim.

The previous expedition was carried out by the NDMA and experts from Switzerland before the 2023 lake outburst in South Lhonak in Sikkim.