Extent of Saltwater Intrusion and the Freshwater Exploitability in the Coastal Vietnamese Mekong Delta. A Case Study in Ham Luong estuary

¹ Institute of Applied Mechanics and Informatics, Vietnam Academy of Science and Technology, Ho Chi Minh 700000, Vietnam
² Southern Institute for Water Resources Planning, Ministry of Agriculture and Rural Development, Ho Chi Minh City, Vietnam

^* Corresponding author: ptbthuc@iami.vast.vn

Abstract

Climate change-driven sea level rise has intensified saltwater intrusion in deltas worldwide, posing significant threats to the exploitation of freshwater resource. In the Vietnamese Mekong Delta, the third largest delta globally, saltwater intrusion is degrading freshwater resources and affecting socio-economic development in the long run. In this paper, we investigate the spatiotemporal extent of salinity intrusion in the Ben Tre Province, the hotspot of salinity disaster is 2021. Long-term salinity monitoring data (1996–2022) has been analyzed, and 3D hydrodynamic model (Mike 3) was Our results indicated that salinity patterns are well-stratified at the beginning and end of the dry season but well-mixed during the middle period. Over the course investigated periods, SI has started progressively earlier in the dry season and increased over the last year. Over the course investigated periods, SI has started progressively earlier in the dry season and increased over the last year. Modeling for SI have also revealed a growing complexity in exploiting freshwater resources, manifesting as challenges related to timing, depth, and geographic location.