Bathymetric and Shoreline Change

Bathymetric shallowing, often accompanied by shoreline advancement toward the sea, is primarily caused by sedimentation, a process commonly known as coastal accretion. Sediment responsible for this shallowing originates from surface runoff and coastal erosion, with sediment loads increasing significantly due to human activities. Major sources include industrial discharges and land clearing in coastal areas, particularly for agricultural development. The resulting impacts may include marine organism mortality, reduced biodiversity, navigation hazards caused by shallowing, habitat degradation or loss, declining natural seafood resources, changes in sediment grain-size distribution, increased water turbidity, and alterations in water depth.

Modeling technology provides an effective tool for analyzing and simulating the processes of bathymetric change and shoreline advancement over time. Modeling scenarios are developed based on sediment inputs from surface runoff and sediments generated through coastal erosion, allowing the long-term evolution of coastal morphology to be evaluated under different environmental and management conditions.

The modeling framework integrates multiple numerical modules. Hydrodynamic Modeling simulates water circulation patterns and water levels. Suspended Sediment Transport and Particle Tracking modules simulate sediment transport and dispersion. Shallow Water Spectral Wave, Wave Refraction–Diffraction, and Wave Analysis modules evaluate wave processes that influence sediment movement. Surface runoff and sediment transport across land are simulated using the Flood Modeling module. Long-term bathymetric evolution and shoreline migration are modeled using Coastal Morphology and Littoral Processes & Shoreline Dynamics modules. Finally, all simulation outputs are integrated with supporting spatial datasets through the Marine GIS module to support mapping, visualization, and spatial analysis.