New Dammed Lake Raises Fresh Flood Fears on Nepal-China Border

Rescuers worked through mud and debris Friday in areas devastated by a catastrophic flash flood along the Nepal-China border, as authorities warned that a newly formed, overflowing lake could trigger further flooding. Nepalese authorities told all security personnel, rescue workers and members of the public deployed in relief efforts to remain on high alert and move to a safe location immediately if necessary. “It hasn’t stopped,” Nepal police spokesperson Abi Narayan Kafle told The Associated Press (AP), saying the rescue operation is continuing but authorities remain on high alert.

Satellite imagery from Chinese state broadcaster Chinese Central Television (CCTV) appeared to show the new lake formed in the same area as Wednesday’s glacial detachment — the sudden collapse of a large chunk of glacier ice — which triggered the flooding downstream. Nepal’s disaster management authority said satellite imagery and preliminary assessments indicate the river has been blocked upstream, forming a growing lake that could burst and cause a sudden downstream flood. CCTV reported Friday morning that the lake’s barrier sits more than 10 kilometers (6 miles) from Gyirong Port — the border crossing engulfed by mud and floodwater — at an elevation of 2,950 meters (9,680 feet), about 1,000 meters (3,280 feet) above the port.

Climate scientists tracking the region said Wednesday’s collapse left several small water bodies, with debris still strewn across the area. “Another dammed lake was formed by the August 26th ice-rock avalanche and this has begun to outflow,” said Qianggong Zhang, head of climate and environmental risks at the Kathmandu-based International Center for Integrated Mountain Development. He said the lake holds a few million cubic meters of water — about 1,200 Olympic-sized swimming pools — in a valley with a limited elevation drop to downstream areas.

With hundreds killed and more than 1,500 people still missing as the region tries to recover, the possibility of another disaster has raised alarm. “There is still a lot of glacial melt going on because of high temperatures, and the water is accumulating at various points, as there is bound to be a lot of debris and rock on the river’s path,” said Jakob Steiner, a geoscientist at the University of Graz in Austria who is based in Dhaka, Bangladesh.

Both Zhang and Steiner said the alerts should be taken seriously, as many rescuers are putting themselves at great risk to find the missing, but they said it is unlikely that a flash flood as devastating as Wednesday’s will happen again.