A concise, source-based record of the catastrophic flood that began high in the Lhende catchment and travelled through Rasuwagadhi, the Bhote Koshi and Trishuli river system.
Toggle the mapped river corridor, assessed source runout and documented places. The blue line follows OpenStreetMap’s Lende Khola–Bhote Koshi centreline; the orange line distinguishes the mountainside failure path before it reached the river.
Search the full page, curated resources and every source retained by the automated archive.
On the morning of 26 August 2026, a large mass of glacier ice and underlying bedrock detached high on the Lirung massif in the upper Lhende catchment near the Nepal–China border. HiRISK's rapid hazard assessment places the source near 28.288708°N, 85.528159°E, at about 5,000–5,200 m elevation, and identifies the event as a rock–ice avalanche and flood.1
Read the full event account ↗Satellite imagery reviewed by HiRISK indicates that the detachment extended roughly 1–1.3 km across. The failed mass travelled to the valley floor below 3,000 m, mobilised additional material, and temporarily blocked the Lhende Khola. Failure of that blockage then generated a powerful flood downstream.1
The flood wave struck the Rasuwagadhi border area at about 08:44 NPT. HiRISK estimates upper-reach flow velocities above 30 m/s, with the wave travelling more than 130 km to Mugling by around 13:00. Large new sediment deposits were observed along roughly 100 km of the corridor to Ghalchhi.1
Clearer post-event satellite imagery showed that the collapse involved not only glacier ice but a substantial section of underlying mountainside bedrock. Independent geomorphologists interviewed by AP reached the same interpretation.5
AP satellite analysis ↗On 26 August, Nepal's Department of Roads reported preliminary damage to at least 19 bridges and about 40 km of roads along the Trishuli corridor.6
Department of Roads reporting ↗Copernicus Emergency Management Service activated Rapid Mapping (EMSR927) on 26 August to assess flood extent and damage in Rasuwa. UNOSAT also produced post-event satellite mapping from Sentinel-2 imagery.34
Copernicus EMSR927 ↗Swipe, use the arrow controls or let the gallery advance automatically. Every image retains its publisher attribution and opens the original report or photo essay.
Copyright remains with each publisher and photographer. Images are presented as source-linked visual references; follow the citation on each slide for original context and reuse terms.
HiRISK reports that the glacier at the source retreated about 450 m between 1990 and 2020. The assessment notes that long-term glacier retreat can remove support from adjacent rock slopes and that warming permafrost can contribute to mountain instability. It describes these as plausible contributing processes rather than a definitive attribution of this specific collapse to climate change.1
Scientists interviewed by the Associated Press made the same distinction: warming and permafrost degradation are increasing concern about high-altitude slope instability, but the precise causal contribution of climate change to this individual failure cannot yet be stated with certainty.5
VIVA-D is the companion evidence archive for this disaster. Contribute original photographs, videos, social-media records, reports or geolocated material—or search the collection for evidence already preserved. The archive keeps vital records available to affected communities, researchers, journalists and policymakers after the emergency period.
Detailed preliminary reconstruction of the source failure, flood process, runout, impacts and climate context.
Dedicated collection of emerging scientific information, media advisories, interviews and regional risk discussion.
European Union emergency mapping activation for flood extent and damage assessment in Nepal.
Post-event satellite-detected mudflow/rockflow mapping derived from Sentinel-2 imagery.
Interactive spatial narrative bringing together flood-related geographic information and mapped resources.
Interactive three-dimensional view of the affected mountain and river corridor.
Photographs, videos, social records, documents and geolocated evidence preserved for long-term research and public use.
National reporting based on the Flood Forecasting Division's technical reconstruction of the flood's downstream progression.
Explains the emerging ice-and-rock avalanche interpretation and the continuing hazard from a newly formed barrier lake.
Reports renewed evacuation and rescue interruptions after a dammed lake began overflowing near the Nepal–China border.
Independent geomorphologists interpret before-and-after satellite imagery and document major downstream geomorphic change.
Places the event in the broader context of transboundary river risk, preparedness and information sharing.
Aerial and field photographs document damage from Rasuwagadhi to Trishuli. Photographs and reporting by Kamal Prasाईं and Dinesh Gautam.
This index is refreshed every three hours from news and humanitarian-report feeds. It discovers relevant material published from 26 August 2026 onward and links to the original source. Discovery is automated; inclusion here is not independent verification.
The page prioritises technical assessments and primary or near-primary institutional reporting. News sources are used to document impacts, evolving interpretation and public response. All links open the original source.