Bhutan flood: Alipurduar moves over 10,000 as Sankosh stays on red alert

A glacial lake burst its banks in Bhutan's Gasa district on Thursday, October 29, 2026, sending a surge of water down the river system that flows into India as the Sankosh and putting north Bengal and western Assam on flood alert. Authorities in West Bengal's Alipurduar district moved more than 10,000 people living along the Sankosh to safer places, and Assam put its Dhubri and Kokrajhar districts on watch. By Friday, October 30, the Alipurduar police said the flow had eased slightly, but a red alert stayed in force. No deaths or injuries have been reported in India.

A glacial lake outburst flood happens when water held behind a natural wall of ice or loose rock at the foot of a glacier breaks through, often suddenly. The water rushes downstream carrying mud and boulders, and it can travel long distances in a few hours. As Himalayan glaciers retreat, the lakes in front of them grow, and governments in the region now track the ones most likely to burst.

The Indian response this time relied on early warning. Because the flood began in Bhutan and had to travel down the river before reaching the plains, there was time to warn district officials and move people out of low-lying villages along the Sankosh. Officials said people had been moved before the water arrived. That is the main reason no casualties have been reported in India so far. It also shows how much India's border districts depend on quick information from Bhutan and on the Central Water Commission's river gauges.

The event will add to questions about how prepared the eastern Himalayan states are for such floods. North Bengal's rivers rise in the hills and run through farmland and settlements, so even a moderate surge can damage homes, crops and roads. Long-term safety depends on monitoring dangerous lakes, sharing data across the border and keeping evacuation plans ready.

Short-term: Evacuated families in Alipurduar will stay in shelters until officials lift the red alert. Farms and roads near the Sankosh may be damaged if the surge spreads over the banks. Assam's border districts will stay on watch as the water moves downstream.

Long-term: The event strengthens the case for joint India-Bhutan monitoring of high-altitude lakes and early-warning systems that reach villages directly, and for district disaster plans that treat GLOFs as a regular risk, not a rare one.

Who is affected: Residents of riverside villages in Alipurduar and nearby districts; families in Dhubri and Kokrajhar in Assam; farmers along the Sankosh; travellers on routes between north Bengal and Bhutan; and disaster response agencies.

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