This study investigates the spatial and temporal dynamics of shoreline deformation along the San Bartholomeo River over 30 years (1995–2025) using an integrated geospatial approach. The research combines Interferometric Synthetic Aperture Radar (InSAR) and Digital Shoreline Analysis System (DSAS) techniques to quantify both vertical land motion and horizontal shoreline change. Results reveal a decline in land area from 32.622 km² (56.65%) in 1995 to 30.284 km² (52.59%) in 2025, alongside an increase in water body extent, indicating progressive shoreline retreat. Shoreline change rates varied significantly, with erosion reaching −8.04 m/yr and accretion up to 16.73 m/yr. Net Shoreline Movement (NSM) and Shoreline Change Envelope (SCE) analyses further highlighted zones of persistent erosion and high variability. InSAR-derived deformation patterns confirmed the presence of subsidence contributing to shoreline instability. The findings demonstrate that a combination of hydrodynamic forces, sediment imbalance, and anthropogenic activities drives shoreline deformation in the study area. This study contributes to improved shoreline monitoring by integrating vertical and horizontal deformation metrics, providing a robust framework for sustainable shoreline management in deltaic environments.

This study proposes an integrated approach combining geographic information systems (GIS) and geotechnical analyses to assess the stability of the Oued Ayda mountain lake dam, located in the Siliana Governorate, northwestern Tunisia. The mechanical properties of the embankment and foundation materials were integrated into a Mohr-Coulomb geomechanical model, while the pore water pressure distribution was simulated for various representative hydromechanical scenarios: end of construction, normal operation, rapid drainage, and short- and long-term empty reservoir conditions. The stability analysis, performed using the Morgenstern-Price method with the SLOPE/W software (GeoStudio), reveals high safety factors on the upstream side (SF > 3 in the short term and SF ≥ 2 in the long term), indicating good resistance of this slope to hydraulic and mechanical stresses. Conversely, the results show that the downstream slope exhibits significantly lower safety factors, ranging from 1.335 to 1.338 under long-term conditions, particularly during normal operating and rapid drainage scenarios. These reduced values indicate a high vulnerability of this slope to persistent saturation and adverse hydraulic gradients. In conclusion, although the dam exhibits satisfactory overall stability, the downstream slope remains the most vulnerable area of the structure. The results underscore the need for rigorous management of water level fluctuations and suggest reinforcing the drainage system or implementing targeted stabilization measures to ensure the long-term safety and durability of the structure.