August 31, 2026
Keshav Lall Maharjan
Vice president, Association of Regional Agricultural and Forestry Economics, Japan


Events around 8:00 a.m. on August 26
From July through August, Nepal is in the midst of the monsoon season (rainy season), a time when it rains almost all day, every day. On August 26, the Kathmandu Valley was cloudy, and the rain had been coming and going intermittently since early morning. The rain itself wasn’t particularly heavy. The 9:00 a.m. news reported that Rasuwagadi, a remote border town deep in the mountains of Rasuwa District bordering China (about 125 km north of Kathmandu), had been swept away by a flash flood. Since it was that time of year, I assumed it was just damage caused by heavy rain in the mountains and didn’t take it too seriously. However, as time passed and I watched the news and images posted on YouTube, I saw one scene after another of massive flooding in the Bhotekoshi and Trisuli river basins, where roads, bridges, villages, and towns were being swept away. The images of swollen rivers engulfing bridges and towns with muddy torrents were beyond imagination; in my mind, they overlapped with the images of rivers flowing backward during the tsunami in Tohoku, japan some years ago. I thought this phenomenon could be described as an “inland tsunami.” As this news spread worldwide alongside these terrifying images, I began receiving messages the very next day from friends and acquaintances around the globe concerned about my safety, which made me take the gravity of the situation even more seriously. This was because here in Kathmandu (the Kathmandu Valley), where I am, nothing out of the ordinary had happened—it was just a typical rainy season day. The government seemed to share my perspective, as there were no particular rescue efforts or other actions taken with urgency.

What happened?
The weather forecast for the Rasuwa region on August 26 called for sunny skies followed by rain, and it appeared there had been no rain, just as on the previous day. However, shortly before 9:00 a.m., a flash flood suddenly surged forward with tremendous force. The images show the muddy torrent crashing into the Chinese border checkpoint, creating a massive wave that, in the blink of an eye, engulfed the imposing, stately building along with dozens of parked buses and cars, sweeping them all away in the floodwaters.
Initial news reports stated that at 8:37 a.m. that same day, a 4.4-magnitude earthquake struck Kyirong County (Kyirong/Gyirong/Jilong-xian; Nepali: Kerung) in Tibet, China. As a result, a glacial lake in the area burst, triggering a flash flood that surged down with such ferocious force—as if a dragon had leaped from the mountain—sweeping away everything in its path. According to one account, the flood traveled the approximately 20 km from the source (the glacial lake) at 5,140 m to the Kerung border area at 1,800 m in just 7 minutes. A simple calculation shows that it plunged down a drop of over 3,300 m at a speed of about 3 km per minute (over 170 km/h), carrying debris and brush with it. Given the immense initial damage caused by this massive flood, it is puzzling that the Chinese side did not provide the Nepalese side with information about the glacial lake outburst and the flash flood. Some media outlets were critical, arguing that if the information had been available, the Nepalese side could have evacuated the area and at least significantly reduced the loss of life.
The following day, the USGS (U.S. Geological Survey) announced that there had been no earthquake in the region at that time. Instead, the area experienced seismic intensity equivalent to a 5.2-magnitude earthquake. This was caused by a massive avalanche and rock slide on the slope of Mount Langtang Lirung near the border; the vertical drop was approximately 1 km, and the mass was estimated at 4.4 megatons. I was stunned by these dizzying figures. I convinced myself that earthquakes truly occur with such unimaginable force.
In addition, the Chinese Ambassador to Nepal issued a statement refuting claims by some media outlets that the massive flooding was caused by an earthquake on the Nepalese side not on the Tibetan side and that China had failed to provide information to Nepal. However, since the USGS has ruled out the possibility of an earthquake, the immediate purpose of this statement may be to deflect media criticism directed at China. The ambassador stated that the two countries need to share information and coordinate their response moving forward, and expressed his intention to do so in the coming days.

As of August 30, it can be said that this major disaster was not caused by a single factor, but rather by cascading disasters, including avalanches, rockfalls, the formation and bursting of glacial lakes, the formation and bursting of natural dams caused by sediment accumulation, and flash floods. This flash flood raged for over 300 km from Raswagadi in the northern mountainous region to the southern Tarai basin plain of Chitwan. Reports indicate that the river’s water level rose to between 7 and 9 meters during the event. In other words, along the paths and rivers through which the flash flood passed, it swept away everything up to a height of 9 meters—including roads, bridges, hydro-power plants, factories, buildings, vehicles, livestock, crops, trees, and people. Many of the items swept away in the mountainous regions—including the bodies of the deceased—have been found in the plains where the river’s current slows. According to official reports, more than 500 people have died, and more than 1,500 are missing and unaccounted for. Of these missings, approximately 500 are foreigners. I would say these numbers are expected to rise significantly in the coming days. According to the Japanese Embassy in Kathmandu, five Japanese nationals believed to have been in the region are also unaccounted for.

In recent years, this road has been considered a convenient route for pilgrimages to Mount Kailash, and it appears to attract many tourists and pilgrims. It is also a region that has undergone rapid development and infrastructure improvements as a trade route with China, featuring many warehouses and a constant flow of trucks transporting cargo. It is also an agricultural region famous for chicken and pig farming, dairy farming, rainbow trout aquaculture, and vegetable production. The Trisuli River appears to be well-suited for hydroelectric power generation; there are already more than seven power plants in its watershed, generating 790 megawatts of electricity and helping to meet a portion of the country’s power demand. All of this was wiped out in an instant. The cost of the damage is sure to be substantial.
At this point, rescue operations are being conducted on a nationwide scale, with the military also deployed, prioritizing the rescue of people. Until yesterday, the government’s policy was to exclude foreign rescue teams and conduct rescues independently; however, it appears that pressure from various countries—including the United States, India, China, Australia, and Japan—to allow participation in rescue operations on a case-by-case basis, including to ensure the safety of their own citizens, has led to a change in policy. These requests were made through diplomatic channels, and it seems the government has now decided to accept foreign assistance for certain specialized tasks, such as DNA testing of the deceased. However, the Indian military is deeply involved in the rescue efforts, and Chinese rescue teams are also operating in the border regions. It could be argued that the Nepalese government’s policy diverges from the principle of prioritizing the saving of lives.
A person rescued by the county from a tunnel at a power plant stated, “There are still many employees inside the tunnel, and I’m worried about their safety.” At the sites where the deceased are being laid to rest, many people from far and near are desperately searching to see if their family members or acquaintances are among the bodies.
It appears that on the Tibetan side as well, there are several fatalities and approximately 500 people missing as a result of this disaster. The Chinese Prime Minister, Deputy Prime Minister, and others have visited the site, and the nation appears to be mobilizing its full resources to organize rescue efforts.
In Japan, too, urban flooding caused by recent heavy rains and flooding in Chiba has been ongoing, as has the flooding caused by heavy rains and flooding in Ishikawa and Toyama a few days ago and now Fukui. It is concerning that such floods and natural disasters have been increasing worldwide in recent years.