Impact of Saltwater Intrusion on the Quaternary Aquifer Using Geophysical Methods at East El Amal City, East Ismaillia, Egypt

This study aims to identify horizontal and vertical brackish water zones within the quaternary aquifer of a resource-rich area using a combination of hydrochemical and geophysical methods. Fourteen groundwater and two surface water samples were analyzed for major anions and cations to assess water quality and saltwater intrusion. The seawater mixing index, based on concentrations of magnesium, sodium, sulfate, and chloride ions, was calculated to estimate seawater intrusion. Additionally, a groundwater quality index was developed to quantify the degree of seawater intrusion. Sixteen Schlumberger Vertical Electrical Soundings and ten 2D profiles were conducted along two lines, revealing four geoelectrical layers: dry fine sand and silt, brackish water-bearing sand and silt, saline water-bearing sand and silt, and clay. Layers B and C contain water, and the findings indicate that groundwater near the Suez Canal shows signs of saltwater intrusion. However, 50% of samples also suggest dissolution of marine deposits or freshwater. The study recommends drilling new wells up to 76 meters deep in the eastern part of the area, while hand-dug wells are suitable for the western region at depths of 8 meters.