SHIMLA: Himachal Pradesh has identified 67 vulnerable glacial lakes, including several in remote, high-altitude areas, and is working to establish early warning systems for four of the most vulnerable lakes in Kinnaur and Lahaul-Spiti, Special Secretary, Disaster Management, Pushpinder Rana, said on Saturday. The state is monitoring the identified lakes using satellite imagery and other scientific data to detect changes that could heighten the risk of glacial lake outburst floods (GLOFs). It is also exploring technical solutions to install sensors and transmit real-time data from remote locations where conventional communication networks are unavailable.
Rana told news agency ANI that the identification of a large number of vulnerable glacial lakes was a cause for concern, especially as recent disasters in the Himalayas have shown that major incidents can occur without conventional warning signs such as heavy rainfall. "Number bada hai, chinta ka vishay toh hai hi (The figure is huge, it's a matter of concern). At the State Centre for Climate Change, we have identified 67 such lakes which are above 10 hectares in area. We are analysing them through satellite and other data to see whether any such situation is developing in them," he said.
Glacial lake outburst floods (GLOFs) occur when water stored in or around a glacial lake is suddenly released, sending large volumes of water downstream. These events can trigger flash floods, damage infrastructure and pose a serious threat to settlements in downstream valleys. Rana said recent incidents in the Himalayan region had highlighted the difficulty of predicting such events solely on the basis of rainfall forecasts. He said the state was therefore seeking technological solutions that could allow vulnerable lakes to be monitored continuously, particularly those situated in inaccessible terrain. "Until we find an innovative way to move forward on this, we will not be able to take effective steps regarding them," Rana said.
Rana said Himachal Pradesh had submitted a proposal to the National Disaster Management Authority (NDMA) to establish early warning systems for vulnerable glacial lakes. He said work had been taken up on four lakes in Kinnaur and Lahaul-Spiti under the National Landslide Mitigation Programme, with a focus on strengthening monitoring and early warning capabilities. The lakes include Parchu Lake and vulnerable locations in the Sangla-Kinnaur region, besides sites in Lahaul-Spiti. The proposed systems are intended to detect potentially dangerous changes in lake conditions and communicate warnings to authorities and downstream populations.
However, Rana said installation of such systems at high-altitude locations remained a major technological challenge. "The early warning system is a technical challenge. The problem is that these locations are in very remote areas where there is no network connectivity. Where will the sensors be installed, how will they be installed and how will the data be transferred? These are the challenges," he said. The state is working with the Centre for Development of Advanced Computing (C-DAC) to develop technological solutions to address these challenges. Rana said the state would begin installing an early warning system at Dipang Ghat once it receives final approval from the NDMA.
Alongside early warning systems, the government is undertaking High Flood Level (HFL) marking in downstream areas that could potentially be affected by a sudden release of water. "The High Flood Level marking in the downstream areas that could be affected is also being taken up at Dipang Ghat. The process is underway," Rana said. Rana said regular monitoring and community awareness would form an important part of the preparedness strategy around vulnerable lakes. "The idea is that we will move forward towards an early warning system. The High Flood Level marking and regular monitoring will also be deployed at such locations," he said.
The state's approach is also linked to scientific studies of Himalayan glaciers and glacial lakes using satellite-based observations. Experts studying the Himalayas have increasingly used remote sensing and satellite imagery to track changes in glaciers and glacial lakes, particularly in high-altitude areas that are difficult or hazardous to access on the ground. Satellite data allow researchers to compare changes in glacier extent and lake formation across different Himalayan basins over time. Studies in Himachal Pradesh have examined basins such as the Sutlej and Spiti, documenting changes in glacier area as well as the number and size of glacial lakes. The availability of higher-resolution satellite imagery has further improved the detection of smaller water bodies and enabled more precise monitoring of changes in their extent. Such scientific monitoring is important because an increase in the number or size of glacial lakes, changes in surrounding glaciers, unstable moraine dams and other physical changes can indicate evolving risks, although individual lakes require site-specific assessment before being classified as an imminent GLOF threat. Rana said satellite data would therefore remain an important component of the state's monitoring strategy.
Rana said GLOF risks could not be addressed by Himachal Pradesh or India in isolation because the Himalayan river systems and glacial landscapes extend across international boundaries. "There are around 1,000 such lakes within the Indian side of the border, and to understand what is happening and how it is happening, we definitely need international knowledge and exchange," he said. He stressed the importance of sharing information about developments in high-altitude areas and upstream river systems, particularly where changes could have consequences for downstream populations. The issue assumes added importance for Himachal Pradesh because several major river systems originate in or pass through high-altitude Himalayan terrain.
Rana said the state was also strengthening its broader disaster information and response mechanism. The emergency helpline 1077 is available to report disasters and potential hazards, while Emergency Response Centres at both the district and state levels operate round the clock. He said information received from different sources, including the India Meteorological Department, is assessed and verified before authorities take action. As Himachal Pradesh faces growing risks from GLOFs, flash floods, cloudbursts, landslides and other climate- and weather-related hazards, officials say a combination of satellite surveillance, scientific assessments, ground-level monitoring, early warning systems, HFL mapping and rapid emergency response will be crucial to reducing risks in vulnerable Himalayan valleys.
