Assessing Climate-Driven Salinity Intrusion through Water Accounting: A Case Study in Ben Tre Province for More Sustainable Water Management Plans

This scientific paper delves into sustainable water management strategies for Ben Tre Province of the Vietnamese Mekong Delta (VMD) in light of water-infrastructure plans that have been impacted by climate change-induced salinity intrusion. Specifically, we aim to mitigate the effects of salinity intrusion for the province while promoting long-term environmental sustainability. In doing so, a water accounting framework was applied, mostly based on the MIKE11 hydrodynamic modeling and water balance calculations, to determine current and future water stress issues based on two main scenarios of extreme drought year 2016 (baseline) and the future year 2030 under climate change for a medium-low emission scenario (RCP4.5). The study found that salinity intrusion significantly causes severe water stress in the future year 2030 compared to the baseline year 2016, while the existing water management methods are relatively inadequate to control salinity intrusion, leading to over 57% of the area affected by medium to critical water stress levels, although it will go along with planned water infrastructures. Additionally, a system of triple rice cropping converted two rice cropping and upland cropping with 40% water demand cutoff was found to be the most suitable measure for 2030. Particularly, water-saving and water demand reduction should be incorporated into infrastructural planning for sustainable water management. Our study provides valuable insights for policymakers and stakeholders, not only for the province and the VMD, but also other regions facing similar challenges.