Kathmandu [Nepal], July 30 (ANI): Heavy rainfall in Tibet early Wednesday morning triggered flooding in several rivers flowing into Nepal, prompting authorities to issue flood warnings in three districts.
Rasuwa District, which borders Tibet and experienced a deadly flash flood on July 8 that killed seven people and left over a dozen missing, is again under alert after the Lhende River swept away infrastructure near the Nepal-China border.
The latest rainfall in Tibet has caused the Trishuli River to swell, significantly raising water levels around Uttar Gaya in Rasuwa and the Trishuli 3B Hub in Kispang. Authorities have issued urgent warnings as the water flow continues to rise in the Rasuwagadhi area.
Rasuwa’s Assistant Chief District Officer, Dhruba Prasad Adhikari, urged “residents living in low-lying coastal areas to remain vigilant,” citing the “ongoing flood originating from the Rasuwagadhi region near the Nepal-China border.”
“The District Disaster Management Committee and local disaster response teams under Uttar Gaya Rural Municipality have been mobilized. The rural municipality and police administration have requested immediate cooperation from the public in adhering to the safety notice,” Adhikari told ANI by phone.
Similar warnings were issued in the neighboring districts of Nuwakot and Dhading, where the Trishuli River has swollen due to the influx of floodwater from the Lhende River along the Nepal-China border.
The District Administration Offices of both Nuwakot and Dhading have urged residents living along riverbanks to remain alert to possible flooding.
Preliminary assessments by Nepal’s Department of Hydrology and Meteorology—supported by satellite imagery, local border officials, and geologists—confirmed that the flood originated when a section of long-frozen permafrost suddenly gave way near the river’s source, which flows into Nepal through Gosainkunda Rural Municipality-1.
Permafrost consists of compacted rock, snow, and soil that remains frozen below 0°C year-round. Even slight increases in rainfall or temperature can destabilize it, leading to sudden floods or landslides.
At least four glacial tributaries of the Lhende River originate in Tibet. On the Nepali side, the catchment area spans glacial regions between Langtang Lirung and the Sangbu Ri ridge, extending as far down as the Dudhkunda Ghattekhola area.
The Lhende River merges with the Trishuli River downstream of the Nepal-China Friendship Bridge at Rasuwagadhi, which was destroyed in the recent flood.
Other glacial tributaries—including the Tibu Glacier to the northeast, the Purupe Glacier further upstream, and another glacier northwest of Langtang Himal—all contribute to the Lhende River. These catchments collectively house at least seven glacial lakes on the Tibetan side, with a smaller lake visible near Dudhkunda in Nepal.
Due to rising global temperatures, these permafrost regions have experienced increased rainfall in recent years. The warm precipitation accelerates the melting of permafrost—frozen layers of snow, sand, and rock—that had remained stable for decades at subzero temperatures.
