Effects of tides and pumping on seawater intrusion in coastal aquifers

To study the effect of combined tidal and pumping on seawater intrusion in the coastal aquifer, groundwater flow and salt transport process in the aquifer with and without tidal influence during 365 days of pumping was simulated based on SUTRA. Without tidal influence, the saltwater wedge keeps invading inland with the increase of pumping time. After considering the influence of tides, the discharge from the upper aquifer-sea interface decreases with pumping, and the upper saline plume gradually expands downward, which inhibits further inland intrusion of the saltwater wedge. With the combined effect of tides and pumping, the area of freshwater and saltwater mixing zone increases significantly.