Yesterday, morning there was big glacier burst near Chamoli village in the state of Uttarakhand and this disturbed the life across many regions of the state. This raised fear across the state, that it might be the repeat of floods of 2015.By evening, the prospect of large scale flooding and destruction had receded.
Most of the expert are of the opinion that it was a Glacial Lake Outburst Flood (GLOF). This is reference to flooding caused downstream due to breach in glacial lake.
Retreating glaciers, like several in the Himalayas, usually result in the formation of lakes at their tips, called proglacial lakes, often bound only by sediments and boulders. If the boundaries of these lakes are breached, it can lead to large amounts of water rushing down to nearby streams and rivers, gathering momentum on the way by picking up sediments, rocks and other material, and resulting in flooding downstream.
GLOF events are not unusual, but their impact depends on the size of the proglacial lake that burst, and location. The breach can be caused by several reasons — in this particular case, for instance, an avalanche was reported in the region two days ago. While GLOF is being considered to be most likely trigger for yesterday’s event, but there are questions surrounding its possibility. As per the Glaciologist of Garwal University “ We do not know of any big glacial lakes in this region. An avalanche is quite common, and possibility of the same can not be ruled out, but avalanche on its own would not result in an increase in the flow of water in the river. The water has to come from a source, and as of now, we do not know what this source is. We would have to visit the area to find out what exactly had happened”.
As per another glaciologist “ It was possible that a glacier lake was present in that area but not known to scientists. There are hundreds of lakes all over the place. We know many of them, but it is possible that there is one we do not know about., After today’s event, I started looking at the satellite images, and I could not find any glacial lake in that area. But may be, if we look at higher resolution satellite images, we might find one. But if there are no glacial lakes in that area, then yesterday’s event would seem to be bit of surprise”.
As per another expert “ If there are indeed glacial lakes in that area, then this event would seem to be a bit surprise. The surprise is also because of timing- A possible reason for the sudden rush of water, like a cloud burst, is not expected at this time of year. Cloud burst would be a rare event during this time of year, it does look like a GLOF event right now. It is possible that an avalanche or a landslide created an obstruction in the flow of the river or streams in the upper mountains, resulting in make shift dam like situation. When the pressure of the flowing water became large, the dam probably gave away, leading to sudden gush of water”.
Adding further to the same – “Then there are issues to consider, like climate change or disproportionate construction in a fragile ecosystem, which were supposed to have contributed significantly to the 2013 disaster as well. As of now, the incident does not seem to have any direct linkage with construction-related activities, or the presence of big dams, but climate change as a factor is not something that can be ignored, particularly in the formation of proglacial lakes. A majority of the glaciers in the Himalayas are known to be receding, all leading to the formation of several proglacial lakes.”
These are some of the possibilities, which might have caused this tragedy, the exact cause will be known only after expert visit the area and study the situation.
As per the latest information available from the area
- At least eight bodies have been recovered from the National Thermal Power Corporation Limited (NTPC) site in the Tapovan area.
- Nearly 180 sheep and goats were believed to have been swept away in the flash flood. Five locals, including three shepherds and two women who were cutting grass, lost their lives.
- According to Indian Air Force (IAF) initial recce report, Tapovan hydro-electric power dam, also known as Rishi Ganga Pour Project, got completely washed away.
- At least four hydropower projects in the area have been damaged, including NTPC’s Tapovan Vishnugad hydropower plant.
- The army has deployed around 400 personnel in rescue operations besides two medical teams. One Engineering task force of the Army is also deployed in Joshimath, and control room has been set up.
- Those who have been resued on Sunday by Indo Tibetan Border Police (ITBP) personnel were given first aid and then shifted to ITBO hospital in Joshimath.
- In Tapovan ITBP has already started rescue work in two tunnels.
In the mean time let us all pray that similar situation should not happen again. Now whether it was a natural tragedy, or this happened due to Global warming and haphazard construction, will be known only after the scientists’ reports
Awaiting your comments and views.
Anil Malik
Mumbai, India
8th February 2021v