Archived event
China reports a new lake forming upstream and warns it could break
This briefing has been overtaken
It was published at 27 August 2026, 11:00 am NPT and is kept online as the record of what was confirmed at that hour. Figures in it are no longer current.
Read the latest briefing: 289 confirmed dead in the Rasuwa flood as searches reach cut-off areas · Current event summary
China's Ministry of Water Resources says a barrier lake, meaning a river blocked by debris into an artificial lake, has formed near the confluence of the Chhochen Khola and the Purepu Tsangpo, inside Tibet close to the Nepal border.
CCTV reports around 2 million cubic metres of water had collected behind it by Thursday morning. Chinese state media warn it could break.
Both rivers are upper tributaries of the Trishuli system. A release would run down the same corridor the 26 August flood took, through Rasuwa and Nuwakot.
Most river gauges on the Bhote Koshi and Trishuli were destroyed in the first wave, so a warning would come with less notice than normal.
Downstream in India, authorities in Bihar have opened the Valmikinagar Barrage on the Gandak, the same river that is called the Narayani inside Nepal, as a precaution, and prepared to move 10,000 to 12,000 people.
Stay off the banks of the Bhote Koshi, the Trishuli and the Narayani until officials say it is clear.
Sources for this briefing
Written and checked by hand against the sources above. Figures are attributed to the bulletin they came from; where two sources disagreed, the lower confirmed figure was used. If something here is wrong, tell us and it gets corrected or removed.