New Delhi: A Himalayan danger lurks in the New Year because of a considerable increase in the number of glacial lakes in Himachal Pradesh and Jammu and Kashmir due to the melting of the glaciers. Bursting of these lakes due to swelling, poses a major threat to the downstream villages.
Fears have been expressed in a study undertaken by the Himachal Centre on Climate Change that reported an increase of the number of glacial lakes up to five hectares in various river basins in the upper Himalayas. Dr SS Randhawa of the Centre carried out the study by comparing the satellite images of 2017 and 2018 and recommended regular monitoring to avert a major catastrophe in case lake bursts.
The study also recommends mechanism to alert the downstream villages, though experts say not much can be done in case of the flash floods caused by the bursting of any lake for a number of reasons.
The Sutlej basin has seen the highest increase of 127 lakes, with as many as 49 spread over more than 10 hectares, followed by 34 lakes in the Chenab basin and 12 in the Ravi basin. In contrast, the number of lakes in the Beas basin went down from 101 to 65. The increase in the Sutlej basin has been 16 per cent within a year.
The number of lakes in the Sutlej basin rose from 642 in 2017 to 769 in 2018, Chenab from 220 to 254 and Ravi from 54 to 66. In the Beas river basin, the lakes fell from 101 in 2017 to 65 in 2018.
The study has correlated the 2013 tragedy of Uttarakhand because of the bursting of an 8-hectare lake in front of the snout of the Chrabari glacier that caused widespread damage downstream during heavy rain and the death of over 100 persons, including the pilgrims. Bodies of many victims in the Uttarakhand tragedy were never recovered.
The findings also assume significance in view of a major threat from the creation of the huge Parechu lake in Tibet in 2004, as that alerted various agencies to monitor the lakes to avert any major loss to life and property in case of bursting.
The comparative analysis of a total number of lakes formed in each basin between 2015 and 2018 reveals an increase of 97 per cent in the Sutluj basin, followed by 32 per cent in the Chenab basin, and 94 per cent increase in the Ravi basin.
Most of the glacial lakes are formed by the accumulation of vast amounts of water from the melting of snow and by the blockade of end moraines in the valleys close to the glaciers. The lakes can also be formed due to landslides causing artificial blocks in waterways. The break of a block can release water from these lakes causing flash floods. Many such incidents have taken place in Nepal, though there are no reports of such incidents in the Indian Himalayas.
