Sikkim will prepare a Glacier Lake Outburst Flood hazard specific evacuation and response plan next year for all the towns and settlements lying on the downstream of the South Lhonak Lake.
Addressing the inception meeting on mitigation of GLOF in South Lhonak Lake on Saturday in Gangtok, Commissioner-cum-Secretary of Land Revenue and Disaster Management Department, Sikkim Tsegyal Tashi said the state would chalk out an effective strategy to avoid the possible problems and threats of South Lhonak Lake due to the GLOF phenomenon.
Sonam Wangchuk, an expert on Himalayan glaciers, said investigations in Indian Himalaya suggest that most of the glaciers are retreating and also losing mass. This consistent shrinkage in mass and extent can affect stream runoff over a long term. In addition, this process can be further influenced if more glacial lakes are formed due to increase in debris cover and if black carbon (soot) is transported in accumulation areas of the glaciers. Therefore, continuous monitoring is needed to understand changing dynamics of Himalayan glaciers.
The South Lhonak Lake, located in the extreme North-western parts of Sikkim is one of the fastest growing lakes in Sikkim. The lake is fast increasing in its size in an extremely abnormal way due to the melting of the South Lhonak glacier attached with the lake and additional melting water from adjoining North Lhonak glacier and main Lhonak glacier. The abnormal growth of the volume of the lake is a great concern in terms of glacial lake outburst floods. The lake is purely a glacial moraine dammed lake which is vulnerable in terms of GLOF.