Simulation of seawater intrusion in coastal aquifers: Some typical responses

Seawater intrusion in coastal aquifers is generally three dimensional\ud (3-D) in nature. In the literature, there is a general lack of reported results on\ud 3-D simulations. This paper presents some typical example simulations of 3-D\ud seawater intrusion process for a specified hypothetical study area. The simulation\ud results presented in this paper are based on the density-dependent miscible\ud flow and transport modelling approach for simulation of seawater intrusion\ud in coastal aquifers. A nonlinear optimization-based simulation methodology\ud was used in this study. Various steady state simulations are performed for\ud a specified study area. Response evaluations consider the effects of vertical\ud recharge on seawater intrusion, effects of boundary conditions, and effects of\ud spatially varying pumping from the aquifer. The 3-D simulations demonstrate\ud the viability of using a planned strategy of spatially varying withdrawals from\ud the aquifer to manage seawater intrusion. It is demonstrated that series of\ud pumps near the ocean-face boundary induce a hydraulic head distribution that\ud can be effectively used for controlling seawater intrusion