On Wednesday, a tragedy struck Sikkim when flash floods due to a cloud burst over the Lhonak lake killed at least 14 people and 100+ people went missing, however, these floods were not something which was unexpected and sudden. Reports are coming in that experts and government agencies have been warning the government about the chances of a deadly glacial lake outburst flood in Sikkim since the last decade but no action was taken.
The glacial lake outburst flood (GLOF) on October 4 led to a rapid rise in water levels in Lake, causing severe damage in Mangan, Gangtok, Pakyong and Namchi districts. South Lhonak Lake, located in Sikkim’s far northwestern region, is one of 14 potentially dangerous lakes susceptible to GLOFs, say studies. The lake is situated at an altitude of 5,200 m (17,100 ft) above sea level and formed due to the melting of the Lhonak glacier.
Glacial Lake Outburst Floods occur when melting glacier-formed lakes burst open due to excessive water accumulation or triggers like earthquakes, causing destructive flash floods downstream.
A study by the National Remote Services Sensing Centre and ISRO in 2012-13 highlighted the associated risks of the lake and estimated a high outburst probability. Later in 2016, an expedition by Sonam Wangchuk of the Students’ Educational and Cultural Movement of Ladakh warned about the potential of a GLOF event. High density polyethylene pipes were installed to siphon off the water from the glacial lake to prevent a GLOF event.
‘Serious potential hazard’ from GLOFs in Sikkim:
A 2021 study published in the journal ELSEVIER identified South Lhonak Lake as a potentially dangerous lake with a high outburst probability. “The glacier receded approximately 2 km in 46 years from 1962 to 2008 and retreated another 400 m from 2008 to 2019. This has raised concerns about the hazard potential of this lake, as the downstream valley is heavily populated with numerous settlements and infrastructure,” the study highlighted. The Sikkim Human Development Report of 2001 had also warned of a ‘serious potential hazard’ from GLOFs in Sikkim.
Please, also have a look into : Sikkim Flash Floods: 14 lives lost, 102 missing, including 22 soldiers
