Nepal water data

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

Water features across the area: rivers, streams, canals, lakes, ponds, and water bodies tagged with `waterway`, `water`, or `natural=water`. Useful for flood-risk modelling, watershed analysis, and environmental basemap context. Coverage reflects where volunteer mappers have been active. Urban areas are usually well represented, remote areas may be sparse. Cross-check critical decisions with local field knowledge. - Source: OpenStreetMap, a free, collaborative world map - Tags: waterway, water, natural - Part of the country exports on HDX by HOT

OpenStreetMap and Overture Maps vector layers for the area flooded in the 2026 Bhote Koshi and Trishuli flood in Nepal, and the ground immediately around it. The area of interest is the observed flood extent of 27 August 2026 widened by 200 metres. The extent itself was mapped from drone, Landsat, PlanetScope and Sentinel imagery and is published here as its own resource, so the water line can be separated from the margin around it. That margin brings in buildings and roads beside the water, so a feature being in this dataset is not evidence that it was flooded or damaged. Clip to the Flood Extent resource when you need figures for the water itself. The area follows the river from Rasuwagadhi to the Narayani confluence, across Bagmati and Gandaki Provinces and the districts of Rasuwa, Nuwakot, Dhading, Gorkha and Chitawan. 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 through the 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. Mapping task boundaries from the Tasking Manager campaign show where volunteers are being asked to map. The bridge damage assessment is reported from the ground by volunteers and lists road bridges with their condition after the flood, deck length where measured, and administrative codes from the same boundaries as the other layers. For the wider 1 km river corridor under assessment, use Nepal Flood 2026 River Corridor. AI-scored building damage from post-event imagery is published separately as Nepal Flood 2026: fAIr Damage Assessment. Subscribe to the dataset for updates as mapping progresses. - Source: OpenStreetMap, Overture Maps, NAXA and volunteer field reports - Part of HOT disaster response exports on HDX by HOT

**UNOSAT code: FL20210630NPL** This map illustrates satellite-detected surface waters in Sudurpaschim and Lumbini provinces, Nepal as observed from a Sentinel-1 image acquired on 4 July 2021 at 18:38 local time and using an automated analysis with Machine learning method. Within the analyzed area of 7,055 km2, about 170 km2 of lands appear to be flooded. The water extent appears to have increased of about 150 km2 since 30 June 2021. Based on Worldpop population data and the detected surface waters in the analyzed area, the potentially exposed population is mainly located in the district of Kailali with ~28,000 people, Banke with ~23,000 people, and Bardiya with ~21,000 people. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to United Nations Satellite Centre (UNOSAT). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to backscattering properties of the radar signal.

**UNOSAT code: FL20210630NPL** This map illustrates satellite-detected surface waters in Province 1, Nepal as observed from a Sentinel-1 image acquired on 4 July 2021 at 05:48 local time and using an automated analysis with Machine learning method. Within the analyzed area of 4,060 km2, about 240 km2 of lands appear to be flooded. The water extent appears to have decreased of about 200 km2 since 1 July 2021 and moved toward India. Based on Worldpop population data and the detected surface waters in the analyzed area, the potentially exposed population is mainly located in the district of Sunsari with ~186,000 people, Morang with ~83,600 people, and Jhapa with ~21,700 people. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to United Nations Satellite Centre (UNOSAT). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to backscattering properties of the radar signal.

**UNOSAT code: FL20210630NPL** This map illustrates satellite-detected surface waters in Province 2, Lumbini, Gandaki,and Bagmati provinces , Nepal as observed from a Sentinel-1 image acquired on 3 July 2021 at 01:37 local time and using an automated analysis with Artificial Intelligence based methods. Within the analyzed area of about 17,000 km2 and, about 830km2 of lands appear to be flooded. Based on Worldpop population data and the detected surface waters in the analyzed area, the potentially exposed population is mainly located in the district of Parsa with ~386,000 people, Rautahat with ~221,500 people, Rupandehi with~148,800, and Bara with ~148,200 people. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to United Nations Satellite Centre (UNOSAT). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to backscattering properties of the radar signal.

**UNOSAT code FL20221117NPL** This map illustrates satellite-detected surface waters in Sudurpaschim and Lumbini Provinces, Nepal as observed from Sentinel-2 images acquired on 25 & 30 October 2022 (Cumulative). Within the analyzed area of about 5,600 km², a combined 52 km² of lands appear to be flooded on the 25th and the 30th of October 2022. Water extent appears to have decreased of about 37 km² since the 15th October 2022. Based on Worldpop population data and the detected surface waters, about 23,000 people are potentially exposed or living close to flooded areas, of which 10,000 are located In Janaki, Tikapur, Geruwa, Rajapur, Thakurbaba & Madhuwan Palikas. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT).

**UNOSAT code FL20221117NPL** This map illustrates satellite-detected surface waters in Sudurpaschim and Lumbini Provinces, Nepal as observed from a Sentinel-2 image acquired on 15 October 2022. Within the total analyzed area of about 4,700 km², ~70 km² of lands appear to be flooded. Based on Worldpop population data and the detected surface waters about 35,000 people are potentially exposed or living close to flooded areas, of which 18,000 are located In Janaki, Tikapur, Geruwa, Rajapur, Thakurbaba & Madhuwan Palikas. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT).

**UNOSAT code: FL20240928NPL** This map illustrates the floods using Sentinel-1 images acquired on 27 September 2024 at 05:56 local time (00:11 UTC). Within the analysed area of about 7,000 km², a total of about 50 km² of land appears to be affected by flood waters. Based on Worldpop spatial demographic data, about 19,000 people are exposed or living close to flooded areas. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to the backscattering properties of the radar signal.

**UNOSAT code: FL20240928NPL** This map illustrates the floods using Sentinel-1 images acquired on 29 September 2024 at 18:15 local time (12:30 UTC). Within the analysed area of about 20,000 km², a total of about 110 km² of land appears to be affected by flood waters. Based on Worldpop spatial demographic data, about 58,000 people are exposed or living close to flooded areas. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to the backscattering properties of the radar signal.

**UNOSAT code: FL20240928NPL** This map illustrates the floods using Sentinel-1 images acquired on 01 October 2024 at 17:59 local time (12:14 UTC). Within the analysed area of about 6,000 km², a total of about 55 km² of land appears to be affected by flood waters. Based on Worldpop spatial demographic data, about 18,000 people are exposed or living close to flooded areas. Water extent seems to have increased by about 14 km² since 27 September 2024 This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to the backscattering properties of the radar signal.

**UNOSAT code: FL20240928NPL** This map illustrates the floods using Sentinel-2 images acquired on 01 & 06 October 2024 at 10:42 local time (04:57 UTC). Within the analysed area of about 18,000 km², a total of about 300 km² of land appears to be affected by flood waters. Based on Worldpop spatial demographic data, about 115,000 people are exposed or living close to flooded areas. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to the United Nations Satellite Centre (UNOSAT).

**UNOSAT code: FL20210630NPL** This map illustrates satellite-detected surface waters in Nawalparasi West, Rupandehi and Kapilbastu districts, Lumbini province, Nepal as observed from a Sentinel-1 image acquired on 7 July 2021 at 06:12 local time and using an automated analysis with Machine learning method. Within the analyzed area of about 1,500 km2 and, about 67km2 of lands appear to be flooded. The water extent appears to have decreased of about 110 km2 since 2 July 2021 and moved toward India. Based on Worldpop population data and the detected surface waters in the analyzed area, the potentially exposed population is mainly located in the district of Rupandehi with ~59,000 people and Nawalparasi West with ~5,200 people. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to United Nations Satellite Centre (UNOSAT). Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to backscattering properties of the radar signal.

**UNOSAT code: FL20210630NPL** This map illustrates satellite-detected surface waters in Province 1 and 2 as observed from a Sentinel-1 image acquired on 1 July 2021 at 05:58 local time and using an automated analysis with Artificial Intelligence based methods. Within the analyzed area of about 110,000 km2 and, about 645km2 of lands appear to be flooded. Based on Worldpop population data and the detected surface waters in the analyzed area, about 700,000 people are potentially exposed or living close to flooded areas. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to UNITAR-UNOSAT. Important note: Flood analysis from radar images may underestimate the presence of standing waters in built-up areas and densely vegetated areas due to backscattering properties of the radar signal.

**UNOSAT code: FL20210630NPL** This map illustrates satellite-detected surface waters in Kaski and Syangja districts, Gandaki province, Nepal as observed from a Sentinel-2 image acquired on 4 July 2021 at 10:41 local time. Within the analyzed cloud free zones of about 500 km2, a total of about 25km2 of lands appear to be flooded. Based on Worldpop population data and the detected surface waters, about 17,000 people are potentially exposed or living close to flooded areas. The potentially exposed population is mainly located in the Kaski district with ~16,000 people. This is a preliminary analysis and has not yet been validated in the field. Please send ground feedback to United Nations Satellite Centre (UNOSAT).