2 glacial lakes increase alarmingly in size, raise flood risk in parts of Himachal along Parvati, Baspa

Shimla: The expansion of Himalayan lakes Vasuki in Kullu district and Sangla in Kinnaur due to glacial melt and climate change has raised concerns about potential flooding in Parvati river in Manikaran Valley and Baspa river in Kinnaur.

However, a recent survey report confirms that both lakes are currently stable, with no leakage detected. The findings were revealed in a survey report released on Friday by Chief Secretary Prabodh Saxena.

The survey, conducted by scientists and engineers from the Centre for Development of Advanced Computing (C-DAC), measured the depth and size of these glacial lakes while also assessing landslide risks on strategically important roads.

Expansion of glacial lakes

Vasuki Lake, located at 4,500 metres in Sosan, Kullu, and Sangla Lake, situated at 4,710 metres in Kinnaur, have both expanded due to climate change and melting glaciers.

The report states that Vasuki Lake’s perimeter is 1.65 km, with a maximum depth of 36.91 metres and an average depth of 14.48 metres.

Between 2017 and 2024, the lake’s area has increased by 3.02 hectares, from 10.36 hectares in 2017 to its current size. It now holds 2.16 million cubic metres of water.

Similarly, Sangla Lake has also experienced a 0.87-hectare increase in area, growing from 13.4 hectares in 2017 to 14.29 hectares in 2024. The lake currently holds 1.52 million cubic metres of water.

Flood risk for hydropower projects and settlements

The report highlights Parvati river as particularly vulnerable to flooding. There are concerns that an outburst of Sangla Lake could impact the JSW Baspa Hydropower Project, endangering lives and infrastructure in the Sangla region.

To mitigate risks, the report recommended an annual field survey of these lakes and the establishment of an early warning system to continuously monitor water flow and potential hazards.

Landslide-prone areas identified in Shimla

In addition to glacial lake expansion, the report also identified 15 landslide-prone locations on two key roads in Shimla, including Panthaghati to NH Crossing and Kennedy Chowk to Annadale Helipad.

These locations pose a threat to road accessibility, and authorities are expected to take preventive measures based on the findings.

The report underscores the growing impact of climate change on Himachal Pradesh’s mountainous terrain, emphasising the need for continuous monitoring and disaster preparedness to protect both infrastructure and local communities.

TNR