This study, carried out in the framework of the MedProgramme Project, applies the DRASTIC model to assess the intrinsic vulnerability of the transboundary coastal aquifer shared by Albania and Montenegro, with particular emphasis on the Lake Sasko area and the Pentari Plain. The DRASTIC method, an acronym representing Depth to water, Recharge, Aquifer media, Soil media, Topography, Impact of the vadose zone, and hydraulic Conductivity, was used to generate a vulnerability map based on hydrogeological and environmental parameters. The region is characterized by complex hydrogeological settings, where the interaction between shallow alluvial aquifers, karst systems, and surface water bodies such as Lake Sasko plays a significant role in groundwater dynamics.

Results indicate moderate to high vulnerability in the studied areas, particularly around the Pentari Plain (Albania) and the western margins of Lake Sasko (Montenegro). These zones exhibit shallow water tables, permeable soils, and high recharge potential, which enhance the susceptibility of the aquifer to contamination from agricultural runoff and human activities. The DRASTIC index values range from 120 to 185, corresponding to moderate to high vulnerability classes. The findings highlight the need for targeted land-use planning, pollution prevention strategies, and enhanced transboundary cooperation to safeguard the groundwater resources in this ecologically sensitive and geopolitically important region. This study provides a scientific basis for sustainable water resource management and supports ongoing efforts to harmonize environmental monitoring frameworks across national borders.