Guwahati: Hours after a likely glacial lake outburst flood (GLOF) at the Lhonak Lake at Chungthang, North Sikkim, early Wednesday, led to widespread flooding in the region, government officials claimed five bodies had been recovered from Golitar, Singtam, in Gangtok district, while three people had been rescued alive from the same area.
A statement by the Sikkim State Disaster Management Authority (SSDMA) also reported one death in West Bengal.
Meanwhile, search operations are underway for at least 23 Army personnel reported missing.
Army public relations officer, Lieutenant Colonel Mahendra Rawat, said in a statement that the outburst caused flash floods in the Teesta river, affecting Army establishments along the Lachen valley. Military vehicles parked at the Bardang area, near Singtam town in Gangtok district, have also suffered damage, he added.
An Army statement had initially attributed the flooding to a cloud burst.
According to an update by the Central Water Commission (CWC) the GLOF in portions of Lhonak Lake in North Sikkim caused water levels to rise with very high velocities of about 15 metre per second.
A high alert was sounded in North and East Sikkim as Teesta’s water rose late Tuesday night.
Speaking to local media, Superintendent of Police, (Mangan district), Sonam Detchu, said all police stations in the low-lying areas were put on alert, and residents living along the river banks were advised to evacuate to higher ground.
Homes have been washed away and bridges damaged. An alert was sounded and residents of Dikchu, Singtam, and Rangpo were evacuated to safer areas.
The Indreni bridge in Singtam is among those claimed by the flooded Teesta.
Flooding washed away both the old and new bridges at Phedang which serve as the entrance to Lower Dzongu. Additionally, the lower section of Adhaarsh Gaon in Singtam was reportedly submerged by the floodwaters.
The small town of Chungthang in North Sikkim is said to be completely cut off from the rest of the region, after flood waters damaged a bridge that connects Mangan and Chungthang.
A multi-agency approach is being taken with the help of civil administration that is closely monitoring the situation, ThePrint has learnt.
Prime Minister Narendra Modi also posted about the calamity on social media platform X (previously Twitter), saying he had assured state Chief Minister Prem Singh Tamang of “all possible support in addressing the challenge”.
Spoke to Sikkim CM Shri @PSTamangGolay and took stock of the situation in the wake of the unfortunate natural calamity in parts of the state. Assured all possible support in addressing the challenge. I pray for the safety and well-being of all those affected.
— Narendra Modi (@narendramodi) October 4, 2023
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What’s a GLOF
When a glacier melts, the water collects to form a lake, which is held by a natural dam made of rocks and sediments, known as a moraine. GLOFs take place when the water overflows from the moraine. An earthquake can also destabilise the dam that is holding the water in the lake.
While Sikkim experienced moderate rainfall Tuesday, that itself is not enough to have resulted in the flood situation. An India Meteorological Department statement has predicted widespread light to moderate rainfall over Sikkim during the next three-four days.
“The lake likely burst around 1 am last night. Yesterday’s [Tuesday’s] earthquake [in Nepal] may have triggered it,” Sarad Chandra, director CWC, told ThePrint.
An earthquake of magnitude 6.2 on the Richter scale occurred in Nepal Tuesday.
In February 2021, Chamoli district in Uttarakhand witnessed flash floods which are suspected to have been caused by GLOFs.
Relief and rescue operations
According to government sources, four relief camps have been set up at Singtam and about 270 people have been shifted to the relief camp at Singtam Senior Secondary School.
At Dikchu, 150 people have been rescued and sheltered in relief camps, sources said.
Gangtok district collector Tushar Nikhare visited all low-lying areas in the district.
Government departments have been put on a high alert and the State Disaster Response Force (SDRF) has been carrying out search and rescue operations since early morning at vulnerable places, government sources added.
(Edited by Smriti Sinha)
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