In a tragic turn of events, the serene state of Sikkim in India’s northeast was shaken by devastating flash floods triggered by heavy rain. The catastrophe occurred when a glacial lake near Lhonak Lake overflowed by a cloudburst, leading to a torrential deluge that wreaked havoc across the region. At least 19 lives have been lost, and the fate of more than 100 individuals remains uncertain. The Sikkim flash floods also severely damaged roads, bridges, and crucial infrastructure.

The calamity, described as a “sudden cloudburst,” occurred over Lhonak Lake in the northern part of Sikkim. The Indian Army reported that this event unleashed rapid and destructive water surges downstream into Sikkim’s Lachen Valley, causing water levels to surge to heights 15-20 feet above normal. A cloudburst, known for its abrupt and devastating rainstorms, was to blame.

One of the major casualties of this catastrophe was the Chungthang Dam, also known as the Teesta Dam. It is an integral part of a significant hydropower project in the state and was swept away by the ferocious floods. Furthermore, districts across the affected areas have witnessed the destruction of drinking water supplies and sewage treatment plants, compounding the misery.

Rescue and recovery operations are in full swing, with state and national disaster response teams actively engaged in relief efforts. While flooding is not uncommon in Sikkim due to its susceptibility to flash floods and landslides, the increasing frequency and intensity of extreme weather events attributed to the climate crisis are a matter of concern.

The Glacial Lake Outburst

The Indian Space Research Organization (ISRO) has released dramatic images that shed light on the extent of the disaster. These images reveal that over 60% of the water stored in Lhonak Lake was drained following the cloudburst-induced glacial lake outburst. This phenomenon occurs when a glacial lake’s water level rises excessively or the surrounding land or ice collapses, leading to a catastrophic release of water and debris.

Satellite imagery dated September 28 showed the lake holding approximately 167.4 hectares of water, while an image from October 4 depicted the lake significantly reduced, containing around 60.3 hectares of water. ISRO commented that the lake’s burst, with the drainage of approximately 105 hectares of water, likely triggered the flash flood downstream in the Teesta River.

Scientists had long recognized the potential danger posed by Lhonak Lake, categorizing it as one of the region’s rapidly swelling glacial lakes with a high risk of a glacial outburst, as evidenced by numerous studies. Sikkim’s Disaster Management Authority had initiated expeditions to the site and identified the risk, prompting the installation of pipelines to mitigate the situation temporarily.

Last May, during a consultation workshop, the state government underscored the urgent need for an early warning system regarding glacial lakes in Sikkim. The director of Sikkim’s Department of Science and Technology emphasized the need for proactive measures to address the looming threat.

As Sikkim grapples with the aftermath of this devastating flash flood, the state and its residents face immense challenges in rebuilding and recovering from this natural disaster while raising questions about the urgency of addressing climate-related risks in vulnerable regions.

Sikkim Flash Floods continue to be a stark reminder of the vulnerability of regions like Sikkim to climate change.

Also Read: Flash Floods In Sikkim: 23 Army Personnel Missing