Dr. Tuan Pham Van, Dr. Sucharit Koontanakulvong
Water Resources System Research Unit
Faculty of Engineering, Chulalongkorn University, Thailand
Although the Vietnamese Mekong Delta (VMD) comprises two main distributaries with high discharge, including dense a network of natural and human-made tributaries, and it would appear that this should provide a copious supply of water to the region even in dry season. However, because of the lack of physical infrastructure and financial capacity, there is low utilization of the supply along with an uneven availability of fresh surface water resulting in water deficits throughout the region. Located in the coastal area of VMD, Tra Vinh Province is considered as a typical site for VMD, where fresh surface water is very limited in dry season due to salinity intrusion, population and economic growth. Since the early 2000s, groundwater exploitation has been increasing dramatically to satisfy water demand for multi-users during dry season and causing negative issues including storage depletion, salinity movement and land subsidence.
In order to understand the change of GW demand in the future, this study will use an analysis of groundwater use mechanism in combination with the data such as population growth, water consumptions (domestic water supply, industry, agriculture, and aquaculture) to estimate future groundwater demand under three climate projections corresponding with three GCMs (IPSL-CM5A-MR, GFDL-CM3 and GISS-E2-R-CC) under the medium emission (RCP 4.5). The results of socio-economic on groundwater is assessed by different groundwater demand scenarios at case study scale. Three groundwater demand scenarios will be fed with the fully calibrated MODFLOW and MT3DMS using the climate data inputs from three climate scenarios to evaluate the impacts of groundwater abstraction on groundwater level and salinity GW movement until 2030. The results obtained from Tra Vinh province will be used as lessons learned to develop adaptive measure options such as store water by ponds, reduce GW demand by land-use change and implementation pathways to cope with sustainable groundwater development for Tra Vinh Province in VMD.