Science & Tech · Science & Environment · 6 hrs ago
Satellite assessment finds Bhutan lake shrank 73% after glacial flood
A glacial lake outburst flood hit Bhutan’s Gasa district on October 29, 2026.
The flood came from Sintaphu Tsho, a lake below Wakila Mountain in the Lungo area.
Satellite analysis found that Sintaphu Tsho lost 73% of its surface area, shrinking from 24.13 hectares to 6.54 hectares.
A nearby lake on a glacier also shrank, by 24.4%, but it remained more than twice its 2016 size.
The flood damaged facilities at Gasa Tshachu, a popular hot spring, and prompted flash flood warnings in parts of West Bengal and Assam.
The findings show why ongoing satellite monitoring matters for tracking risks in the vulnerable Himalayan region.
A satellite assessment found that Bhutan’s Sintaphu Tsho glacial lake lost 73% of its surface area after an outburst flood on October 29.
The lake’s area fell from 24.13 hectares to 6.54 hectares, according to the assessment by Suhora Technologies.
A nearby supraglacial lake lost 24.4% of its area, shrinking from 16.51 hectares to 12.47 hectares.
The flood destroyed facilities at Gasa Tshachu, a natural hot spring beside the Mo Chhu River.
The flood also prompted flash flood warnings for parts of West Bengal and Assam.
- Who
- Suhora Technologies conducted the satellite assessment.
- What
- A glacial lake outburst flood was followed by a 73% reduction in Sintaphu Tsho’s surface area.
- When
- The flood occurred on October 29, 2026.
- Where
- Sintaphu Tsho is in Bhutan’s Gasa district, below Wakila Mountain in the Lungo area of Laya Gewog.
- Why
- The lake burst its banks, causing a glacial lake outburst flood.
This story does not have two clearly opposing sides.
Sintaphu Tsho measured 23.33 hectares and the supraglacial lake measured 5.74 hectares in the late-October imagery.
Sintaphu Tsho’s surface area reached 24.13 hectares, its peak in the decade studied.
The glacial lake outburst flood occurred in Bhutan’s Gasa district.
Sintaphu Tsho measured 6.54 hectares and the supraglacial lake measured 12.47 hectares.
- Sintaphu Tsho after flood
- 6.54 hectares
- Sintaphu Tsho reduction
- 73%
- Supraglacial lake after flood
- 12.47 hectares
- Supraglacial lake reduction
- 24.4%
- Flood date
- October 29, 2026
- Flood location
- Gasa district, Bhutan
What people are saying
The findings highlight the importance of continuous monitoring of glacial lake systems and the role of satellite-based Earth observation in understanding changes across vulnerable Himalayan terrain
Timely access to such insights can support better awareness of evolving environmental risks and strengthen monitoring and preparedness across the region.