The rising threat of glacial lake outbursts due to accelerating glacier melt has put Himachal Pradesh’s hydroelectric power projects, roads, and bridges at significant risk. A recent study has warned that expanding glacial lakes in Kullu, Kinnaur, and Lahaul-Spiti could cause catastrophic floods, urging the need for early warning systems and continuous monitoring.
A team of nine experts and scientists conducted a bathymetry survey and risk assessment of critical glacial lakes, including Vasuki Lake in the Sosna area of Kullu (4,500 m) and Sangla Lake in Kinnaur (4,710 m). The study, undertaken by the Centre for Development of Advanced Computing (C-DAC), found that the Parbati river in Kullu district is highly vulnerable to flooding due to increasing water flow. While no leaks have been observed yet, the study warned that a breach in Vasuki Lake could severely impact the JSW Baspa hydroelectric power project, while Sangla in Kinnaur could also face substantial damage.
Climate change-driven glacial melting has led to a rapid expansion of these lakes. Vasuki Lake, with a depth of 14.48 m, has grown from 10.36 hectares in 2017 to 13.38 hectares in 2024, marking an increase of 3.03 hectares. Sangla Lake, which spans 15.73 hectares, has expanded by 0.87 hectares over the same period.
Another alarming finding concerns the Ghepang Ghat Lake (4,068 m) in Lahaul-Spiti, which has expanded by 178 percent over the past 33 years, growing from 36.49 hectares to 101.30 hectares. The National Remote Sensing Centre, Hyderabad, conducted the mapping of this high-risk lake under the National Hydrology Project (NHP). The report highlights that the Ghepang Ghat glacier is melting at an unprecedented rate, leading to rapid lake expansion and significant ice loss at the glacier’s snout. Downstream settlements, witnessing increasing urbanization, are at high risk if the lake bursts.
The study has identified 34 settlements, 57 bridges, and 107 km of road network that could be affected by potential glacial lake outbursts. Low-lying areas such as Sissu, Tandi, Tibok, Thirot, Triloknath, Udaipur, Tehtlo, Purthi, Sach, and Phindru are particularly vulnerable. Experts have stressed the urgent need for proactive measures, including real-time monitoring and the installation of early warning systems, to mitigate the risks associated with glacial lake outbursts in the region.
