NEPAL 2026 — The Flood That Went Underground
On the morning of August 26, 2026, a glacier collapsed near Langtang Lirung, a peak in Nepal's Langtang National Park close to the border with Tibet. No rain was falling. A huge piece of ice and rock broke off about 3 miles above sea level and fell nearly three-quarters of a mile into the valley below. Seismometers around the world picked up a magnitude 5.2 signal, but the U.S. Geological Survey found it came from the collapse itself, not from an earthquake. Within minutes, that falling ice and rock became a Nepal flash flood of mud, water, and debris racing down the Trishuli River.
The Trishuli River valley is lined with hydropower projects, and many of them are built around long tunnels bored deep into the mountains. When the flood hit, hundreds of workers were inside. More than 900 people working on 12 hydropower projects were reported missing, and the Nepal Electricity Authority says 13 projects were damaged, knocking about 431 megawatts off the grid. The early warning system never saw the flood coming, because it was built to watch for monsoon floods, not a glacier collapse, and its upstream stations were swept away. The Nepal tunnel rescue became one of the hardest in the world. Two workers were pulled out alive after about nine days underground, but they were among very few.
Now the search has turned from rescue to recovery. This week, Nepali Army teams working inside the 9.8-kilometer tunnel of the Trishuli hydropower project known as Upper Trishuli-1 recovered at least 29 bodies in two days, cutting them free from steel mesh buried in mud. Nepal's disaster authority has raised the number of missing to 6,150. And one question still has no answer: how many people were underground when the water came in. In this video, we explain the geology behind the Nepal glacier collapse, why the tunnels became traps, and why this natural disaster may never have a final count.
Sources: U.S. Geological Survey, Nepal Electricity Authority, Nepal's National Disaster Risk Reduction and Management Authority, Nepali Army recovery updates, and University of Calgary geologist Daniel Shugar.