Satellite detected water extent over Khammouan & Savannakhet Provinces, Lao PDR as of 04 August 2023

**UNOSAT code: TC20250722LAO, GDACS ID: 1001181** This map illustrates the satellite detected water extent in Bolikhamxai and Khammouan Provinces, Lao PDR as observed from Sentinel-1 satellite images acquired on 28 July 2025 at 05:50local time (22:50 UTC). Within the analyzed area of approximately 14,000 km², about 200 km² of land appears to be affected by floodwaters. Based on WorldPop population data and the flood extent, approximately 14,000 people are potentially exposed or living close to the 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: FL20190905LAO** This map illustrates satellite-detected surface water in Khammouan and Savannakhet Province of Lao PDR as observed from Sentinel-1 imagery acquired on 11 September 2019. Within the analysed extent of about 8,300 km2, a total about 332 km2 of land appear to be flooded as of 11 September 2019. 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 Sentinel-1 imagery acquired on 11 September 2019 may seriously underestimate presence of standing flood water in built up areas due to backscattering of the radar signal

**UNOSAT code TC20220928LAO, GDACS Id: 1000922** This map illustrates satellite-detected surface waters in Khongxedone District, Saravan Province & Sanasomboon, Champasak Province, Lao PDR as observed from a Sentinel-1 image acquired on 1 October 2022 at 05:45 local time. Within the extent of this map of 600 km2, about 14 km2 of lands appear to be flooded. Based on Worldpop population data and the detected surface waters in the map extent, about 1,800 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 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: TC20250722LAO, GDACS ID: 1001181** This map illustrates the satellite detected water extent in Vientiane Capital, Vientiane and Bolikhamxai Provinces, Lao PDR as observed from Sentinel-1 satellite images acquired on 27 July 2025 at 06:00 local time (23:00 UTC). Within the analyzed area of approximately 19,000 km², about 130 km² of land appears to be affected by floodwaters. Based on WorldPop population data and the flood extent, approximately 12,000 people are potentially exposed or living close to the 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: FL20240913LAO** This map illustrates the floods detected using Sentinel-1 images acquired on 11 September 2024 at 06:07 local time. Within the analysed area of approximately 60 km², about 7 km² of land appears to be affected by floodwaters, including 6 km² of croplands. According to WorldPop spatial demographic data, an estimated 2,500 people are exposed to or living near the flooded areas. Please note that this is a preliminary analysis and has not been validated in the field. We welcome any ground feedback that can be provided to the United Nations Satellite Centre (UNOSAT). Important: Flood analysis based on radar images may underestimate the extent of standing water in built-up or densely vegetated areas due to the radar signal's backscattering properties.

**UNOSAT code TC20220928LAO, GDACS Id: 1000922** This map illustrates satellite-detected surface waters in Sukhuma District, Champasak Province, Lao PDR as observed from a Sentinel-1 image acquired on 1 October 2022 at 05:45 local time. Within the extent of this map of 360 km2 , about 12 km2 of lands appear to be flooded. Based on Worldpop population data and the detected surface waters in the map extent, about 2,500 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 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.