Shimla 27May
The scenic village of Sissu, which has emerged as a major tourist attraction in recent years, is now facing a serious environmental threat due to the rapidly expanding Gepang glacial lake near the Gepang glacier in tribal district Lahaul-Spiti.
A recent joint study by the Himachal Pradesh State Disaster Management Authority (SDMA) and the National Remote Sensing Centre has warned that the growing lake could trigger a devastating glacial lake outburst flood (GLOF) in the future, posing a major risk to villages, roads and bridges downstream.
According to the report, the lake’s area has expanded from nearly 36 hectares in 1989 to over 100 hectares in 2022 due to rapid glacier melting caused by climate change.
Scientists have classified the lake as a “moraine-dammed glacial lake”, formed behind a fragile natural barrier made of rocks, sand and debris. Experts warned that heavy rainfall, landslides, avalanches or glacier collapse could breach the natural dam at any time.
The study has placed Sissu in the highest-risk “red zone”. In the event of a lake burst, floodwaters could reach the village within 20 to 21 minutes at speeds exceeding 40 kmph, with water depths in some areas estimated to reach up to 20 metres.
Experts cautioned that the disaster would not involve water alone, but also massive debris, boulders and glacier rocks, significantly increasing the scale of destruction. The distance between the lake and Sissu is estimated to be around 11 km, leaving very little response time for residents.
Local residents have also expressed concern over reports of another lake forming in the Gepang region. They fear that any sudden glacier collapse could lead to catastrophic consequences across the valley and beyond.
Authorities have installed an early warning system in vulnerable areas, though it is currently in the testing phase. The administration has also started awareness campaigns for locals and tourists.
Meanwhile, thousands of tourists continue to visit Sissu daily during the peak tourist season. Residents believe uncontrolled tourism and rising vehicular traffic are adding environmental pressure to the fragile Himalayan ecosystem and have called for measures to regulate tourist inflow.
Former SDMA director DC Rana said the lake’s size and depth are continuously increasing due to glacier melting, making scientific monitoring, disaster preparedness and timely warning systems crucial for protecting lives and infrastructure in the region.
