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On Wednesday morning (local time), 26 August 2026, a catastrophic debris flow and flood was likely triggered by rapid slope failure involving a glacier in Lāṅṭāṇ National Park, Nepal, near the border with China. This debris flow and flooding travelled nearly 100 km and impacted populated areas downstream along the Lende Kholā and Trishuli̇̄ Kholā rivers, including the Rasuwāgaḍhi̇̄ border post between China and Nepal. Preliminary media reports and imagery analysis indicate many buildings and infrastructure have likely been buried or destroyed, including a vital highway connecting China and Nepal.
Our primary focus is supporting response and recovery efforts through hazard mapping using satellite imagery.   
This landslide event page serves as an event summary to communicate timely science information to our partners. This information includes what is currently understood about the event and ongoing activities of the USGS and partner agencies and may be subject to change. 
 
 
 
USGS geologists are mapping the inundation boundary of the debris flow and flood by using satellite imagery. By comparing images taken before and after the event, geologists can identify newly affected areas, trace the limits of inundation, and disturbed surfaces from undisturbed terrain.  
 
The slope failure involving a glacier generated energy equivalent to a M5.2 earthquake. The debris flow and flood travelled approximately 100 kilometers (approximately 62 miles). A second seismic event was recorded approximately 3-hours later, generating energy equivalent to a M4.2 earthquake. 
At this time, it is unclear if the initial slope failure was a landslide incorporating part of a glacier or a glacial collapse. A glacial collapse is where a portion of a glacier breaks off, and the debris rapidly moves downslope. The glacial debris contained water and ice that rapidly melted, picking up more material and water as it flowed downslope in the existing stream and river channels, creating a fast-moving, far-traveled landslide and flood laden with boulders and other rubble. 
 
The geology of the area is composed of high-grade metamorphic rocks (gneisses, quartzites, marbles).   This mountain was previously the source of another large debris avalanche in 2015 caused by a M7.8 earthquake. There, several million cubic meters of ice and debris collapsed, starting at 5,000-meter elevation, and fell nearly 1,900 meters, burying a village, and killing more than 200.  
 
Contributors to this page include Stephen Slaughter, Corina Cerovski-Darriau, Jenny Riker, Steven Sobieszczyk, Lauren Schaefer, Elaine Collins, Elizabeth Eiden, and Marísa Macías. 
View the USGS earthquake event page for the primary seismic event. 
View the USGS earthquake event page for the secondary seismic event. 
Learn more about landslides.   
Learn more about landslide preparedness.   
Learn more about the National Landslide Susceptibility Map.   
Learn more about the Landslide Hazards Program.  
Learn more about USGS Landslide Response.   
 
 
1711 Illinois St
Golden, CO 80401
United States
1711 Illinois St.
Golden, CO 80401
United States
On Wednesday morning (local time), 26 August 2026, a catastrophic debris flow and flood was likely triggered by rapid slope failure involving a glacier in Lāṅṭāṇ National Park, Nepal, near the border with China. This debris flow and flooding travelled nearly 100 km and impacted populated areas downstream along the Lende Kholā and Trishuli̇̄ Kholā rivers, including the Rasuwāgaḍhi̇̄ border post between China and Nepal. Preliminary media reports and imagery analysis indicate many buildings and infrastructure have likely been buried or destroyed, including a vital highway connecting China and Nepal.
Our primary focus is supporting response and recovery efforts through hazard mapping using satellite imagery.   
This landslide event page serves as an event summary to communicate timely science information to our partners. This information includes what is currently understood about the event and ongoing activities of the USGS and partner agencies and may be subject to change. 
 
 
 
USGS geologists are mapping the inundation boundary of the debris flow and flood by using satellite imagery. By comparing images taken before and after the event, geologists can identify newly affected areas, trace the limits of inundation, and disturbed surfaces from undisturbed terrain.  
 
The slope failure involving a glacier generated energy equivalent to a M5.2 earthquake. The debris flow and flood travelled approximately 100 kilometers (approximately 62 miles). A second seismic event was recorded approximately 3-hours later, generating energy equivalent to a M4.2 earthquake. 
At this time, it is unclear if the initial slope failure was a landslide incorporating part of a glacier or a glacial collapse. A glacial collapse is where a portion of a glacier breaks off, and the debris rapidly moves downslope. The glacial debris contained water and ice that rapidly melted, picking up more material and water as it flowed downslope in the existing stream and river channels, creating a fast-moving, far-traveled landslide and flood laden with boulders and other rubble. 
 
The geology of the area is composed of high-grade metamorphic rocks (gneisses, quartzites, marbles).   This mountain was previously the source of another large debris avalanche in 2015 caused by a M7.8 earthquake. There, several million cubic meters of ice and debris collapsed, starting at 5,000-meter elevation, and fell nearly 1,900 meters, burying a village, and killing more than 200.  
 
Contributors to this page include Stephen Slaughter, Corina Cerovski-Darriau, Jenny Riker, Steven Sobieszczyk, Lauren Schaefer, Elaine Collins, Elizabeth Eiden, and Marísa Macías. 
View the USGS earthquake event page for the primary seismic event. 
View the USGS earthquake event page for the secondary seismic event. 
Learn more about landslides.   
Learn more about landslide preparedness.   
Learn more about the National Landslide Susceptibility Map.   
Learn more about the Landslide Hazards Program.  
Learn more about USGS Landslide Response.   
 
 
1711 Illinois St
Golden, CO 80401
United States
1711 Illinois St.
Golden, CO 80401
United States