Coupled three-dimensional modelling of groundwater-surface water interactions for management of seawater intrusion in Pingtung Plain, Taiwan

• Published in: Journal of hydrology. Regional studies Vol. 36; p. 100850
• Main Authors: Dibaj, Mahdieh, Javadi, Akbar A., Akrami, Mohammad, Ke, Kai-Yuan, Farmani, Raziyeh, Tan, Yih-Chi, Chen, Albert S.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2021; Elsevier
• Subjects: Coupled model; FEFLOW; Groundwater; Surface water; SWI; Taiwan; Coupled model; Groundwater; SWI; FEFLOW; Surface water; Taiwan
• ISSN: 2214-5818; 2214-5818
• DOI: 10.1016/j.ejrh.2021.100850

[Display omitted] •An integrated model of surface-groundwater interaction is developed.•The first coupled model of Pingtung coastal aquifer was developed.•The model was used for finding artificial recharge locations and SWI mitigation.•The temporal salinity variations of Kaoping River estuary was analysed.•The effects of rainfall on river and groundwater interaction was also monitored. A coupled framework, linking subsurface flow and surface hydrodynamics, is developed and applied to a real-world case study of Pingtung coastal aquifer in southwest of Taiwan, in East Asia. FEFLOW is adopted to develop a 3-D variable density and transient groundwater model of the Pingtung shallow aquifer lying 250 m below mean sea level (MSL). This model is coupled with a 1-D river network model, comprised of the main river and its two tributaries, using MIKE 11 through the IFM MIKE 11 coupling interface. The model is capable of analysing the relationship between rainfall, surface water and groundwater recharge lag time. Also, the analysis of potential river inundation and maximum river discharge enable the model to choose the best location to apply artificial recharge as a management scenario to mitigate the effect of seawater intrusion (SWI). To the authors’ knowledge, the developed coupled model is the first detailed integrated framework analysing the interaction of surface and subsurface water, with the capability to contribute to the restoration, rehabilitation, and management of the river network. The rainfall ratio in the wet season to dry season is significant in this plain comparing with the rest of Taiwan. Also, southern Taiwan experiences the largest sea and river interaction, while Kaoping River playing as a pathway role for inland lead of seawater intrusion.