<p>The Haor region of Bangladesh is a dynamic ecosystem facing significant changes over recent decades due to natural and anthropogenic factors. This study analyses spatiotemporal changes in Land Use and Land Cover (LULC) and water dynamics of Northeastern Haor areas using the Normalized Difference Water Index (NDWI) through Remote Sensing (RS) and Geographic Information Systems (GIS) techniques. The findings reveal notable shifts across four majors land cover classes: water bodies, vegetation, bare land, and built-up areas, indicating critical ecological and socio-economic changes in the region from 1990 to 2023. Waterbodies declined dramatically, from 3188.73 km² (16%) in 1990 to 853.63 km² (4%) in 2023. The decrease reflects hydrological changes caused by unplanned agricultural practices, urban development, and sedimentation. Vegetation cover initially increased from 9155.92 km² (46%) to 13754.53 km² (69%) by 2010, but later dropped to 12700.79 km² (64%) in 2023 due to urban and agricultural activities. Built-up land grew steadily, reflecting urban expansion, while bare land fluctuated seasonally. NDWI analysis showed improved water availability in 2010, but low NDWI values in 2023 highlight ongoing water scarcity. These trends emphasize the need for integrated land and water management strategies to safeguard the Haor ecosystem, promote sustainable practices, and support community resilience.</p> Graphical Abstract <p></p> <p><b>Graphical Abstract Description</b></p> <p>This graphical abstract presents the methodology and key findings of a study on land use and land cover (LULC) changes in the Northeastern Haor region of Bangladesh from 1990 to 2023. This study uses satellite data from Landsat 5 and Landsat 8 OLI-TIRS. The analysis was carried out using the Google Earth Engine (GEE) platform, with the normalized difference water index (NDWI) employed to monitor water body dynamics. Additionally, a supervised classification approach with the random forest (RF) algorithm categorized the land cover into four distinct classes, such as water body, vegetation, bare land, and built-up land. The LULC maps provide a visual representation of the shifting dynamics, including a dramatic decline in water bodies, an increase in built-up areas, and fluctuations in vegetation cover. The inset images highlight specific regions of interest, provides a closer look of land cover changes (NDWI and LULC) from 1990 to 2023. It highlights the impact of urbanization, agriculture, and hydrological factors. This study offers valuable insights into long-term environmental transformations, emphasizing the need for integrated water resource management strategies and land use planning</p>