Uttarakhand Glacier Burst: What caused this another Himalayan Tragedy?

Flash Flood in Uttarakhand's Joshimath, Chamoli District (Image: IANS)

Atleast 67 people have been killed with the discovery of 3 more bodies and over 170 are feared missing, after a glacier burst in Uttarakhand’s Chamoli district on February 7 .

By Proiti Das

Chamoli: The rescue operation has been underway at the Tapovan Project site for a fortnight now since it was destroyed by a flash flood triggered by a glacier burst over the Rishi Ganga and Dhauli Ganga river in Chamoli district two weeks ago.

Highlights:

  • The rescue operation continues at the Tapovan site
  • A natural lake has been formed in Uttarakhand’s Murenda area after the flash floods
  • A team of researchers inspected the threats that can be posed by the artificial lake formed over Rishi Ganga
  • Death toll rises to 67

 

The affected region in Chamoli district, Uttarakhand (Source: The New Indian Express)

A sudden surge of water gushed through the Rishi Ganga river on a peaceful Sunday morning, washing away many houses, temples and completely destroying the Rishi Ganga hydel project dam while extensively damaging the Tapovan Vishnugad hydel project near Raini village in Chamoli.

The disaster has taken the lives of 67 people till now whose bodies have been recovered. Out of which many of them remain unidentified while 170 workers are still missing. More than 300 personnel have joined in the rescue operation. The Indo-Tibetan Border Police (ITBP) along with the National Disaster Response Force (NDRF) and their sister agencies have been conducting search and rescue work.

Uttarakhand Glacier Burst Tragedy Data (Data Source: NDTV)

By the same Sunday evening when the disaster took place, the largescale destruction and flooding receded. Scientists and glaciologists have been travelling to the site to find out the cause for the incident. Meanwhile, the Alakananda river had been flowing at its normal level in Pauri Garhwal after the disaster. Uttarakhand Disaster Response Force has put an alarm system to detect the rise in the water level incase anything similar happens again.

Damaged Dhauliganga hydropower project after a glacier broke off in Joshimath causing a massive flood in the Dhauli Ganga river, in Chamoli district of Uttarakhand, Sunday, Feb. 7, 2021. Photo: PTI

What caused the incident?

The scientists are not sure what exactly triggered the flash flood near Chamoli. An avalanche took place two days prior to the day of the disaster.  The scenario being most talked about is what glaciologists call as GLOF or glacial lake outburst flood.

Many environmentalists have claimed that the climate change and global warming have led to the bursting of a part of the Nanda Devi glacier at Joshimath on February 7.

Scientists have also been looking at the satellite and Google Earth images to detect if there were any glacial lakes near the area. It is likely that  there may be a water pocket, or lake inside the glacier that may have bursted causing the deluge in the Alakananda river.

Glacial Lake Outburst Flood infographic (Information Source: CNBC 18)

Also Read: Uttarakhand Disaster: Reminder for Development and Climate Change Risks

What is this GLOF? How does it occur?

A glacier burst is a rare instance that happens when water dammed by a glacier is released. The glacier then can overflow and cause such floods. It can happen due to erosions, buildup of water pressure, avalanche, earthquake or volcanic eruptions under the ice.

It can also happen when a large chunk of an adjacent glacier breaks and causes massive displacement in the glacial lake.

Similarly in the Himalayan ranges, there are several retreating glaciers that usually result in the formation of lakes at their tips, called proglacial lakes, bound by sediments and boulders. Once there is breach in the boundaries of these lakes, it can lead to large amount of water rushing down to the lower pressure areas in the nearby streams and rivers. In its momentum, it carries away sediments, rocks and everything else in its way depending upon the force.

The possibility of a cloud burst had been eliminated because of its unlikeliness of it during this time of the year.

Even though as scientists and the government have said there is no direct linkage with the construction related activities, the big dams and structures built on these kind of topography makes the ecosystem fragile.

The breaking of the glaciers had been a common phenomenon and usually it doesn’t lead to such a huge destruction. Climate change and man made ecological disruptions have been believed to be the additional factors behind the cause of this disaster.

How well India is prepared to tackle such glacial breaks and disasters?

Last October, the National Disaster Management Authority (NDMA), headed by Prime Minister Narendra Modi issued detailed guidelines on how to reduce and deal with disasters caused by GLOFs.

The NDMA guidelines say that to tackle the problem and reduce the risk, the proglacial lakes that can be potentially subjected to GLOFs needs to identified and mapped. Structural measures needs to be taken to prevent their sudden breach and eventual disasters.

Site of the Tapovan hydel project as rescue works underway, a day after a glacier broke off in Joshimath causing massive flood in Dhauli Ganga River, in Chamoli district of Uttarakhand, Monday, Feb 8, 2021. (Express photo by Gajendra Yadav)

The NDMA has also recommended the use of Synthetic-Aperture Radar imagery to automatically detect changes in water bodies, including new lake formations.

It also has asked for provisions heavy earthmoving and search and rescue equipment. Acknowledging the fact that a disaster area in the Himalayas can at times get inaccessible to earthmovers, NDMA has recommended “innovative methods using locally available natural resources”. It has realized the  importance of innovative and new design lighter machinery which will be more suitable to be carried in the mountains in a disassembled form.

Also Read: Uttarakhand flood: Personalities like Sonu Sood and British PM Boris Johnson extend their assistance for victims

Sources: ANI, PTI, DNA India, Live Mint, New Indian Express