Glacial lake outburst at Shintaphu Lake triggers flood warnings in Bhutan, West Bengal and Assam

A glacial lake outburst flood occurred Thursday evening at Shintaphu Lake in Bhutan's Gasa district, causing the complete washout of facilities at the nearby Gasa Tshachu hot spring. The area had been evacuated beforehand, and no casualties have been reported.

Shintaphu Lake, one of 17 glacial lakes in Bhutan considered potentially dangerous, feeds the Mo Chhu River. Floodwaters have moved downstream, crossing Srigang in Kabesa Gewog, about eight kilometres from Punakha Dzong, and have deposited debris on the Punakha-Gasa Highway.

Bhutan's authorities have warned neighboring Indian states of possible flash floods. The governments of West Bengal and Assam have been alerted, with districts such as Darjeeling, Alipurduar, Jalpaiguri, and Dhubri identified as at risk. In West Bengal's Cooch Behar, officials issued an alert for residents along the Sankosh River, which originates in northern Bhutan and joins the Brahmaputra in Assam.

"My appeal to everyone is that there is no need to panic in any way. We are in alert mode, the administration is fully prompt, and all agencies are actively working," said Amit Kumar Shaw, Superintendent of Police for Alipurduar district.

A solar-powered irrigation lifting system installed earlier this year in the Punakha region was partially damaged by the flood, according to a local press release. The system has ceased operating, and the full extent of damage is still being evaluated.

Glacial lake outburst floods occur when water accumulated in former glacier basins is suddenly released, often due to dam failure triggered by heavy rain, landslides, avalanches, earthquakes or rapid melt, a process intensified by rising temperatures linked to climate change.