Bhutan glacial lake burst prompts flood alerts in West Bengal and Assam
Thimphu: A sudden outburst from Shintaphu Lake in Bhutan’s northwestern Gasa district has set off flash-flood alerts in parts of West Bengal and Assam, prompting authorities on both sides of the border to step up monitoring of river systems flowing out of the Himalayas.
The flood occurred on Thursday evening after water from the glacial lake surged into the Mo Chhu River. The rush of water damaged infrastructure at Gasa Tshachu, a popular hot-spring site near the river. Officials said there were no casualties because people in the area had been moved to safety before the flood arrived.
Shintaphu Lake is among 17 glacial lakes in Bhutan that authorities consider potentially hazardous. The same hot-spring area was badly affected in August 2021, when flooding caused the Mo Chhu to shift its course.
Water from the surge has reportedly moved past Srigang in Kabesa Gewog, roughly eight kilometres from Punakha Dzong, intensifying concern for settlements and infrastructure further downstream. Bhutan has informed West Bengal and Assam about the possible threat to districts along their shared border.
In Assam, Dhubri has been placed on watch, while in West Bengal the Darjeeling hills, Alipurduar and Jalpaiguri are being monitored. Officials in Cooch Behar have also cautioned people living near the Sankosh River, which rises in northern Bhutan and eventually feeds into the Brahmaputra river system in Assam.
Police and district authorities have asked residents not to panic, saying emergency teams are prepared and precautionary steps are being taken. Alipurduar Police District Superintendent of Police Amit Kumar Shaw said agencies were working promptly and expressed hope that local difficulties would be resolved within a few hours.
The flood has also left its mark inside Bhutan. A solar-powered irrigation system installed earlier this year in Punakha’s Dochhukha-Dzomlingthang-Ritsa Chiwog area was partially damaged after the Mo Chhu swelled. Local representatives said the system had stopped working, although officials are still assessing the full scale of the loss.
Debris carried by the flood has also blocked a stretch of the Punakha-Gasa Highway near Dzomlingthang, raising the possibility of disruption to road movement in the area.
Glacial lake outburst floods happen when a lake formed by melting glaciers suddenly releases its water, often because a natural barrier gives way. Heavy rain, landslides, avalanches, earthquakes or rapid ice melt can set off such events.
Scientists warn that warming temperatures are making glaciers retreat faster, increasing the volume of water stored in high-altitude lakes and raising the risk of sudden, destructive floods downstream.
(Inputs from IANS)