Satellite detected water extents in Louangnamtha Province, Lao PDR as of 11 September 2024

**UNOSAT code: FL20190905LAO** This map illustrates satellite-detected surface water in southern provinces of Lao PDR as observed from Sentinel-1 imagery acquired on 6 September 2019. Within the analysed extent of about 60,000 km2, a total about 1,000 km2 of land appear to be flooded as of 6 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 6 September 2019 may seriously underestimate presence of standing flood water in built up areas due to backscattering of the radar signal

**UNOSAT code: FL20240913LAO** This map illustrates the floods using Sentinel-1 images acquired on 18 September 2024 at 06:00 local time. Within the analyzed area of approximately 7,000 km², around 230 km² of land appears to be affected by floodwaters. The extent of the flooding has increased by approximately 50 km² since the previous observation on 13 September 2024. Based on WorldPop spatial demographic data, an estimated 26,000 people are currently exposed or residing near 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 FL20230807LAO** This map illustrates cumulative satellite-detected surface waters over Khammouan & Savannakhet Provinces, Lao PDR as oberved from a Sentinel-1 image acquired on 04 August 2023 at 18:04 local time. Within the analysed area of about 25,000 km², a total of about 160 km² of lands appear to be flooded. Based on Worldpop population data and the detected surface waters in the analysed area, ~18,000 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 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 backscaterring 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: 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