Ghepan Lake
Why in News?
Ghepan Lake is in the news because a five-member Geological Survey of India (GSI) team has launched a 14-day scientific assessment to install an early warning system, responding to severe climate-driven expansion and the critical risk of a Glacial Lake Outburst Flood (GLOF).
Geographic and Technical Profile
- Location: Situated in the Lahaul region of the Lahaul-Spiti district in Himachal Pradesh, India.
- Altitude: Positioned at a high altitude of 4,070 metres (approx. 13,500 feet) above sea level.
- Water Volume: Holds approximately 35.08 million cubic metres of meltwater, making it one of the largest glacial lakes in the state.
- Dimensions: Measures roughly 2,464 metres in length and reaches up to 625 metres at its widest point near the glacial snout.
- Feeder Glaciers: Fed uniquely by three separate hanging glaciers melting off Mount Gipan Go—a rare configuration at this altitude.
- Outflow Channel: Water drains from its south-western edge into the Sissu Nullah, which drops steeply (90m per km) before joining the Chandra River.
Key Environmental and Safety Concerns
- Moraine-Dammed Weakness: The lake is bounded by a fragile natural dam made of loose rocks, sand, and glacial debris.
- Trigger Factors: Heavy cloudbursts, sudden landslides, or massive ice avalanches falling into the lake could displace water and breach the moraine wall.
- The 21-Minute Hazard: Impact models show that if a breach occurs, floodwaters could reach Sissu village in just 21 minutes at speeds of 43 km/h, rising up to 20 metres high.
- Widespread Impact: A catastrophic burst could cause domino-effect flooding downstream through the Chenab River basin, affecting Jammu & Kashmir and stretching into Pakistan.
Cultural and Tourism Significance
- Local Deity: Named after Lord Ghepan (Ghepan Ghat), the chief protector deity of the Lahaul Valley, giving the lake immense religious value to indigenous communities.
- Aesthetic Appeal: Renowned among adventure travellers for its striking, neon turquoise-blue alpine waters.
- Trekking Route: Serves as a challenging, high-end trekking destination that starts from Sissu, requiring navigation through intense boulder fields and active rockfall zones.
