ABSTRACT                                                                                                                                                                   

Coastal environments are dynamic and sensitive systems subject to various natural and anthropogenic influences. This study investigates landform changes near the Kalu River estuary in Sri Lanka from 2017 to 2020, using Geographic Information System and Digital Shoreline Analysis System. Multiple shoreline change analysis methods, including Linear Regression Rate (LRR), Transect line, Shoreline Change Envelope (SCE), and Net Shoreline Movement (NSM), quantify erosion and accretion patterns have been utilized in the study. Zone 2 experienced significant erosion while accretion was observed in Zone 3(see, figure 10) and 717 Kalutara North. The interconnectedness of estuaries and coastal environments is highlighted, emphasizing the direct impact of estuarine changes on nearby beaches. The study underscores the importance of understanding estuarine dynamics in coastal management and planning. It sheds light on vulnerable areas and offers opportunities for coastal protection and sustainable development. The research contributes valuable insights into coastal system complexities, calling for comprehensive assessments to safeguard coastal communities and environments in the face of ongoing environmental changes. The integrated analysis provides a foundation for targeted strategies to mitigate erosion, enhance coastal resilience, and promote sustainable coastal disaster risk reduction (CDRR) practices in the study area. Ultimately, such comprehensive assessments are crucial for safeguarding the ecological integrity and socio-economic well-being of coastal communities and environments in the face of ongoing environmental changes.