A month after the flash flood disaster in Nepal, India's Himalayan state of Uttarakhand has taken steps to install an early warning system on a glacial lake.
This initiative has been started to reduce the damage caused by breaking of glacier lakes in the high Himalayan regions of Uttarakhand, and to strengthen the monitoring and warning system of the lakes.
A team of scientists left from Dehradun on Tuesday to set up an early warning system in Vasudhara Glacier Lake of Chamoli. Vasudhara Lake is also called Vasundhara Lake.
This is the first early warning system in the state to be installed on a glacial lake. Through this, the changes in the lake can be monitored by getting state-of-the-art sensors, satellite communication and real-time data. In this way the danger can be predicted in time.
According to the report of National Remote Sensing Center (NRSC), the water spread area of Vasudhara Tal has increased almost five times in the last six decades.
In the year 1962, this lake was spread over 10.53 hectares, whose water area will increase to 51.07 hectares in the year 2024.
This lake is a supra-glacial lake (formed on the surface of a glacier), which has developed by the joining together of many small lakes.
The state government says that in view of the increasing size of the lake and the potential threat to the areas and other important structures below it, an early warning system is being installed to continuously monitor it and give timely warnings.
This campaign, which started from September 29, is proposed till October 15.
The expedition team includes scientists and technical experts from Roorkee-based Central Building Research Institute (CBRI) and Dehradun-based Wadia Institute of Himalayan Geology.
SDRA, NDRF and ITBP personnel will also be with the team for security, movement and field support of the expedition team in the high Himalayan and inaccessible areas.
Chief Minister Pushkar Singh Dhami said that it is the effort of the state government to strengthen the modern monitoring and early warning system in the high Himalayan regions with the coordination of scientific institutions, experts and all departments related to disaster management.
The expedition members left for Joshimath from Rishikesh on Wednesday morning.
Dr. Amit Kumar, a scientist in the Glaciology Department of the Wadia Institute of Geology and a member of the team, told BBC News Hindi that on October 3, the team will reach the first base camp located at an altitude of approximately four thousand meters.
According to the National Remote Sensing Center report for the year 2023, a total of 344 glacial lakes have been identified in Uttarakhand.
Of these, 13 glacial lakes are identified as high risk lakes.
These include one lake in Bageshwar, four in Chamoli, six in Pithoragarh, one in Tehri Garhwal and one in Uttarkashi.
According to Disaster Management Secretary Vinod Kumar Suman, bathymetric survey of six high-risk glacial lakes has been completed.
In this survey, the depth of the lake, information about the lake bed under water, water holding capacity and total amount of water are assessed.
On August 26, a landslide near the Nepal-Tibet border and the subsequent flash flood caused massive devastation.
The danger of such disasters has also emerged in Uttarakhand. In February 2021, there was a flash flood in Chamoli due to the breakage of large chunks of ice and rocks, in which more than 200 people were killed or missing.
In view of these disasters, the need to monitor the high Himalayan regions and the changes happening there has increased.
According to glaciologist Dr. Amit, work is being done on four aspects which include monitoring of lakes, early warning system, spreading information to the people and measures to reduce risk.
After installing the early warning system, data related to Vasundhara Lake will start being available.
He said, "With this, we will start getting real time data related to fluctuations in the water level of the lake and we will be able to monitor it. We will be able to disseminate the information. If necessary, people can also be alerted through sirens."
He explains that for this the area potentially affected by the lake will be mapped.
"We will also study where there are houses, dams and other structures. From the bathymetric survey, we know the amount of water in the lake. Now we will assess how long it will take for the water to reach the settlements below in case the lake breaks. This will help in determining the response time for each lake and understanding where to install sirens and where to run awareness programs in advance to alert people."
"We will also see if the lake can be slowly drained of water to reduce the risk of it collapsing,"
According to Dr. Amit, the danger associated with every lake is different. It is not necessary that the condition of the lakes of Pithoragarh is like that of Vasundhara Lake. The circumstances are different there. Study of the lakes of Pithoragarh will be started next year.
According to Dr. DP Doval, a scientist in the Department of Glaciology at the Wadia Himalayan Institute of Geology, Automatic Weather Stations (AWS) were installed for the first time near Chorabari Glacier in Rudraprayag district in 2007-08 to understand the condition of the glacier.
Subsequently, six AWS were installed at different heights on Dokrani and Chorabari glaciers in 2011–12.
Talking to BBC News Hindi, he told that for the first time such equipment was installed to study the weather at such a height in the state.
He recalls, “Our field work for glacier studies was good but we were lagging behind in terms of modern equipment in the higher Himalayan region, some of our equipment was washed away in the 2013 disaster. When I went back to see those AWS systems in 2019, they were falling apart due to rust. The quality of the equipment deployed there has to be excellent.”
On this initiative of installing an early warning system to monitor Vasudhara Lake, he said, "The data obtained from these instruments will help us understand the seasonal changes there. We will have accurate data as to when and how much snow is falling or raining. We say that now the duration of summers is increasing and winters are shrinking, then these instruments will give us the real data of temperature fluctuations there."
According to Dr. Doval, "We know the depth of the lake, when the water level of the lake increases or decreases, it can also assess the changes in the shape of the lake. When the water in the lake increases above a certain level, the sensor will trigger and a warning can be issued in time."
Residential areas including Niti, Gamshali begin in Dhauliganga valley, about 18 kilometers below Vasudhara Tal.
According to Dr. Doval, when the water level in the lake reaches above a specified level, the sensor will be triggered and an alert can be issued through the system. In such a situation, there may be about half an hour's time for rescue and response.
Following are the major points of monitoring through these devices:
Water level sensor: Monitoring fluctuations and sudden abnormal changes in the lake.
Automatic Weather Station: Will record meteorological data such as temperature, humidity, rainfall, wind speed and direction, air pressure and light intensity.
Snow Depth Sensor: Monitoring changes in snow depth around the lake.
Snow Sub-Surface Temperature Sensor: Eight sensors will be installed to record changes in temperature at different depths of snow.
Tilt and accelerometer sensors: Monitor tilt, vibration, and movement at selected locations.
Solar power system: Will provide electricity to the equipment installed in the inaccessible high Himalayan region.
Chief Secretary Anand Bardhan said that this initiative being started in Vasudhara Tal will form the basis for installing such systems in other sensitive glacier lakes in future.
Disaster Management and Rehabilitation Minister Madan Kaushik said that the Early Warning System will continuously provide important data like water level, weather, snow condition, water flow, which will help in reducing disaster risk and strengthening the safety of people living in the high Himalayan regions.
