On 26 August 2026, a catastrophic flash flood and debris flow originating in the upper Bhotekoshi river system struck Rasuwa and subsequently propagated downstream through the Trishuli–Narayani river corridor, causing extensive loss of life and destruction across Rasuwa, Nuwakot and several downstream districts. Preliminary scientific analysis indicates that the disaster resulted from a complex cascading process involving a sudden release of water and debris in the upper catchment, potentially associated with glacier and/or landslide-related processes; the precise initiating mechanism remains under investigation. 

The Government's preliminary national situation report estimated that approximately 1.6 million people were affected in some way across the wider disaster area, while the UN Flash Appeal subsequently prioritised more than 84,000 people requiring humanitarian assistance. 

Oxfam conducted an assessment from 4–8 September 2026, with a primary focus on Uttargaya Rural Municipality and the wider market and service systems supporting affected communities in Rasuwa and Nuwakot. It combined community FGDs and KIIs, holding-centre observation, rapid market and trader interviews, WASH technical observation, stakeholder consultations and secondary-data review. The team visited accessible holding centres in Uttargaya and Nuwakot, consulted local-government officials and response actors, and assessed Ghumti/Kalikasthan and Battar/Bidur as key markets capable of supplying affected populations. Direct assessment access to Uttargaya Wards 1–3 was not possible, and populations in holding centres were changing rapidly; findings for those areas should therefore remain provisional until field access and additional technical data become available.