The Central Water Commission monitors the Glacial Lakes & Water Bodies in the Himalayan Region of Indian River Basins. Based on this data, between 2009 & 2021, the area of 146 water bodies has increased (by more than 5%), and that of 175 has reduced (by more than 5%), and another 135 have remained unchanged (change is less than 5%). The Indian Himalayan Region (IHR), often referred to as the third pole of the world, boasts of the largest concentration of glaciers and snow outside the Polar Regions. Across the globe, studies have revealed that glaciers have been receding fast since the onset of the Industrial Revolution in the eighteenth century. As these glaciers thin and withdraw, they give rise to the expansion of glacier meltwater lakes and the creation of new ones. These lakes, nourished by glacier meltwater, are commonly known as glacial lakes. The formation of these glacial lakes typically occurs behind moraine or ice dams as the glaciers recede. A glacial lake outburst flood (GLOF) is a sudden and often catastrophic release of water from a glacier-dammed lake. These events occur when the natural dam, often composed of ice and glacial debris, holding back the water in the lake fails, releasing a significant volume of water downstream. Rapid melting of glaciers as global temperatures rise, earthquakes, and avalanches are some causes of such occurrences. In early October 2023, there was a sudden surge in flows in the Teesta River due to GLOF, which claimed the lives of many, along with severe infrastructural damage. It washed away several bridges, parts of NH-10, and the Chungthang Dam, and has impacted several small towns and infrastructure projects in the upper reaches of the river valley in Sikkim. GLOF Risk in Sikkim was highlighted in many reports previously However, this was not unprecedented. Many studies and reports had earlier flagged the region as highly vulnerable to GLOFs and emphasized on the need to conduct an environmental impact assessment and potentially undertake GLOF risk mitigation measures at least two–three years ago. Earlier this year, the Standing Committee on Water Resources report on Glacier Management in the country was presented in the Parliament. It ranked the lakes with a size of more than 1 hectare for GLOF risk considering glaciological, terrain, and associated characteristics. (Factly’s review of the report can be read here) These lakes are spread out not just in India but over several other Himalayan countries including Nepal, Bhutan, and China. The region is a pristine source of freshwater in the entire Indian subcontinent which is vital for water supply, flood and drought mitigation, irrigation, groundwater recharge, livelihood source, tourism, and biodiversity. However, these lakes are being significantly affected due to climate-driven changes, natural processes, and anthropogenic activities. Owing to different reasons such as draining, rainfall, and rate of melting, among others over the years, the area of the lakes has either increased, decreased, or remained unchanged. CWC monitors glacial lakes in India In this story, we look at the change in the area of these glacial lakes and water bodies over a period of two decades, between 2009 and 2021. For this, data has been taken from Dataful where the information has been compiled from the Central Water Commission’s report. According to the report, the glacial lakes and water bodies in the Indian Himalayan region are monitored using satellite images. Some of the criteria for monitoring the glacial lakes and water bodies in the region are: The area considered for the study is as shown: 467 water bodies with water spread area of 5.38 lakh hectares have been covered in the report The data for 467 glacial lakes and water bodies have been identified in the report, across India, China, Bhutan, and Nepal. Majority of these, 328 were in China, 92 in India, 26 in Bhutan, and 21 in Nepal. The total water spread area of these water bodies was 5.38 lakh hectares, as of 2021. Based on data available for both years, the area of 146 water bodies has increased (by more than 5%), that of 175 has reduced (by more than 5%), and another 135 have remained unchanged (change is less than 5%). The data shows that 25 water bodies recorded an increase in water spread area by more than 40% between 2009 and 2021. A total of 37 water bodies recorded an increase in area by more than 30%. The area of the water body CH_33 in China (part of the Indus basin) has nearly quadrupled (388%). 219% increase in the water body HP_5 in Himachal Pradesh (part of Chenab River, Indus Basin) was recorded. CH_206’s area (in Ganga Basin) grew by nearly 159%.