Nepal Flood 2026 Flood Affected Area, Bhote Koshi and Trishuli

OpenStreetMap and Overture Maps vector layers for the full Bhote Koshi and Trishuli river corridor in Bagmati and Gandaki Provinces, Nepal, for the 2026 flood response. The area of interest is a 1 km buffer around the river centrelines, running from Rasuwagadhi on the China border to the Narayani confluence at Devghat in Chitawan, across Rasuwa, Nuwakot, Dhading, Gorkha, Tanahu and Chitawan. It merges the original partner shapefile for the upper reach with OCHA's HPCS corridor downstream. This is the wide planning view, the whole corridor under assessment rather than the ground that flooded. For data limited to the flooded area, use Nepal Flood 2026 Flood Affected Area, which clips every layer to the observed inundation footprint of 27 August 2026 and a 200 m margin around it. Every layer holds what is standing and what has been lost, so buildings and roads do not vanish from a download once mappers record them as destroyed. `status` says Standing, Damaged or Destroyed, and the Destroyed and Damaged Features layer gathers everything marked destroyed or damaged in one place. Layers are rebuilt straight from OpenStreetMap each day, so they carry volunteer work as it lands. Buildings, schools, health facilities and points of interest also come in an Overture version, which fuses Microsoft, Google and OpenStreetMap and reaches ground volunteers have not mapped yet. Overture follows its own release cycle and will not show mapping done during this response, so for damage work prefer the OpenStreetMap layers and use Overture where their coverage is thin. Subscribe to the dataset for updates as mapping progresses. - Source: OpenStreetMap, Overture Maps - Part of HOT disaster response exports on HDX by HOT

Part of the Humanitarian OpenStreetMap Team response activation for the 26 August 2026 Bhote Koshi and Trishuli flash flood in Nepal. AI-scored building damage per OpenStreetMap footprint across the upper Trishuli and Bhote Koshi corridor, from Rasuwagadhi to the Narayani confluence. Post imagery is a 26-scene Vantor open-data composite (2026-08-27 to 2026-09-08, roughly 0.4 m/px, about 9.8% cloud). Pre imagery is ESRI World Imagery. Building footprints come from OpenStreetMap and cover 20,367 features in the corridor; 8,421 fall inside the analyzed area and carry an AI damage class. Each feature carries `osm_id`, `osm_type`, `building`, a `damage` label (`no-visible-damage`, `minor-damage`, `major-damage`, `destroyed`) and a `damage_confidence`. Evaluated and validated against 3,896 OSM manually tagged affected buildings (3,185 destroyed + 711 damaged, 2026-09-12): destroyed precision 0.91, recall 0.78, F1 0.84; severe (major + destroyed) recall against manually tagged affected buildings 0.75. The reference layer is included in this dataset. Post-event imagery TMS: ``` https://titiler.hotosm.org/cog/tiles/WebMercatorQuad/{z}/{x}/{y}?url=https://production-raw-data-api.s3.amazonaws.com/ISO3/NPL/buildings/hot_flood_npl_buildings_damage_post.tif ``` For the wider corridor context, see Nepal Flood 2026 Flood Affected Area. - Source: OpenStreetMap, Vantor open data, ESRI World Imagery - Part of HOT disaster response exports on HDX by HOT

Overture building footprints and IHME population estimates in the identified impacted area from the 26 August flash flood in Nepal. - 37 sq km impacted - 4,977 intersecting Overture building footprints - IHME 2026 Population Estimate 10,203.8

satellite imagery by Planet, acquired 2026-05-26 to 2026-05-26, 300 cm per pixel, published on OpenAerialMap.

satellite imagery by Naxa Pvt Ltd, acquired 2026-08-25 to 2026-08-26, 1000 cm per pixel, published on OpenAerialMap.

satellite imagery by Planet, acquired 2026-05-26 to 2026-05-26, 300 cm per pixel, published on OpenAerialMap.