Lahaul's expanding lake 'poses threat' to Sissu village

Dipender Manta

Mandi, October 12

Researchers of the Divecha Centre for Climate Change at the Indian Institute of Science, Bengaluru, have warned that the Gepang Gath lake in Lahaul and Spiti district may outburst due to its increasing size, posing a serious threat to downstream Sissu and other villages as it.

The study was conducted by Ashim Sattar, Simon Allen, Martin Mergili, Wilfried Haeberli, Holger Frey, Anil V. Kulkarni, Umesh K. Haritshya, Christian Huggel, Ajanta Gowswami and Raaj Ramsankaran. According to the researchers, the glacial lake outburst floods (GLOFs) pose a severe threat to communities in the Himalayas. However, GLOF mitigation strategies have been implemented for only a few lakes, and future changes in hazards are rarely considered.

The study presented a holistic assessment of the GLOF hazards of the Gepang Gath Lake in Himachal Pradesh. It observed a significant growth in the size of the lake in the past few years. According to the study, if the lake outbursts, it can impact buildings and communities along the banks of the flow channel at Sissu, helipad, Sissu Lake and the riverbank camping sites located in the fan area where the channel meets the Chenab. A few stretches of the Manali-Leh highway could also suffer damaged because of it.

The researchers suggest that there is need to lower the lake by 10 m to 30 m to reduce the chances of damage to exposed elements such as the Sissu helipad, Sissu Lake, and the riverbank camping sites located in the fan area. These infrastructures are exposed to large-magnitude events even after lake lowering.

“The study was based on assumptions of mass movements into the lake of different magnitudes; predicting an anticipated future event is highly uncertain. However, the present study can provide a basis for applying disaster risk reduction strategies in the valley and cost-benefit evaluations of lake-lowering efforts, further recommending a more detailed investigation of the area” the researchers said.

Deputy Commissioner, Lahaul and Spiti, Rahul Kumar told The Tribune that “the district administration will assess the situation by visiting the spot and thereafter take corrective measures accordingly. Human safety is a major concern for the administration and necessary action will be taken in this direction.”