Decline in area under glaciers in 5 river basins in Himachal

Pratibha Chauhan

Tribune News Service

Shimla, December 24

There has been a considerable decline in the area under glaciers in the major river basins of Satluj, Beas, Ravi and Chandrabhaga in Himachal though there has been an increase in the number of lakes, enhancing the potential threat of flooding in downstream areas.

May hit power generation

The hydro-power sector remains one of the main revenue generating sectors in Himachal as the state has a potential of 27,000 MW in the five major river basins. The phenomena of decline in the total area under glaciers could adversely impact power generation.

The latest data compiled by the State Centre on Climate Change in the HP Council for Science, Technology and Environment has revealed that the total area under glaciers is shrinking. It is the Beas basin which has experienced the maximum decline of 14.33 per cent in the total area under glaciers between 2001 and 2018 followed by 8.87 per cent in the Chandra basin.

“Data compiled from satellite imagery of the major river basins in Himachal clearly indicates that there is a continuous retreading trend in the total area under glaciers betwten 2001 and 2018,” revealed Dr SS Randhawa, Principal Scientific Officer, State Centre on Climate Change. He added that there was also a decline in the area under snow in Himachal Pradesh over the last few years.

The hydro-power sector remains one of the main revenue generating sectors in Himachal as the state has a potential of 27,000 MW in the five major river basins. The phenomena of decline in the total area under glaciers could adversely impact power generation as the highest generation takes place in the summers when there is accelerated melting due to high temperatures.

In order to minimise the scope of error, the data compilation included very minute examination of the reduction in area under glaciers in the Spiti, Baspa and Pin basins. A comparison of the satellite images taken in 2001, 2006, 2016 and 2018 was undertaken to arrive at the overall decline in sq kms.

Based on a 2019 study, the Satluj basin has the highest 562 lakes, Chenab basin 242 lakes, Beas basin 93 lakes and Ravi basin 37 lakes. The previous year studies had already indicated the phenomena of increase in the number of glacial lakes which could pose a potential threat to the downstream areas, inhabited by population all along the rivers.

The most worrisome area remains the Karcham and Nathpa region in the Satluj river basin in Kinnaur district. There has been considerable concern over this aspect especially against the backdrop of the catastrophe in Chamoli in Uttarakhand. Some of the largest hydro-power projectrs including the 1500 MW Nathpa Jhakri, 1000 MW Karcham Wangtoo and 300 MW Baspa projects are located in the Baspa-Satluj basin, which is considered to be most vulnerable.

The council has undertaken detailed study of the Geepang Lake in Lahaul Spiti district to identify the potential locations which could be susceptible to damage in case the lake bursts.