Modelling the Groundwater Flow Response to Tidal Fluctuation in a Coastal Leaky Aquifer by separation of variables and Fourier transformation

In this paper, groundwater response to tidal effects in a Coastal Leaky Aquifer is simulated via analytical solutions. The solutions are obtained by application of separation of variables method and Fourier transform method. It is shown that those points of the aquifer near to the coastal shore are much more influenced by the tidal fluctuations in the boundary than the rest of the aquifer. The amplitude of tidal change is significant at points of the aquifer near to the coastal shore and gets smaller with distance from the boundary. In addition, it is shown that groundwater level increases with rises in transmissivity. This phenomenon is more significant when transmissivity is less than 400 m2/hr . Also, the groundwater head rises with rises in recharge rate. The effect of variations in transmissivity and recharge rate on hydraulic head is more significant at points located between 30 and 75 meters and less significant at points near to the coastal shore. The presented analytical solution is compared and verified with those results obtained from MODFLOW.