Retreating glacier of Ganga, name Gangotri, will not drastically influence the flow of Ganga as the river is not totally dependent on glaciers for its water, said the Indian government.
"The percentage of snow and glacier contribute the water in Ganga but it is not the sole medium of water for the biggest river in India. After reaching to a certain low, the impact of glacier water progressively reduces, said the environment minister Anil Madhav Dave.
“At the downstream of the river, rainwater and sub-surface flows contribute more than 70% of the flow of river Ganga at Haridwar", the minister added, while responding to a Parliament Question, quoted the National Institute of Hydrology and referred to the mapping done by the country's space agency - Indian Space Research Organisation (ISRO).
The ISRO had carried out mapping of Himalayan glaciers using Indian satellite data during 2004 to 2007. The study shows that there are 34,919 glaciers spread over 75,779 sq. km. in Indus, Ganga and Brahmaputra basins covering Himalaya and Trans-Himalaya including Karakoram region.
The ISRO had also monitored the 'advance' and 'retreat' of 2018 glaciers, across the Himalayan region using satellite data of 2000-01 to 2010-11. Dave, in his written response, said, "The study shows that 87% of glaciers showed no change, 12% glaciers retreated and 1% glaciers have advanced".