An integrated assessment of the groundwater chemistry of the aquifers at North Giza Governorate, using multivariate statistical analysis, ionic ratios, and geochemical modeling

Abstract

ROUNDWATER is an important source of water in Egypt that has been heavily exploited in recent decades. This has led to the expansion of the west Nile Delta cultivated area through the New Delta project (in the area to the west of the old Nile Delta), that pose additional stresses on the water resources. Fourteen groundwater samples from the semi-confined and five samples from the unconfined Quaternary aquifers were collected, thirteen samples from the Miocene (Moghra) aquifer, and one sample from the deep Nubian aquifer were also collected and analyzed for various parameters. A comprehensive assessment of the four aquifers in the study area were done using statistical analysis, biplots, Piper and Gibb's diagrams, as well as temporal comparison of the water chemistry. The statistical analysis output indicates the interplay between human activities (anthropogenic factors) and the interaction with the bearing rocks (geogenic factors) that affect the water chemistry of the aquifers. The hydrogeochemistry of the different aquifers indicates that the semi-confined Quaternary and the Moghra aquifers are best used for irrigation, while the unconfined Quaternary aquifer belongs to the Na-Cl water type and the deep Nubian aquifer water is brine according to the salinity classification. Additionally, caution must be taken to mitigate the potential impact of contamination from the use of fertilizers and excessive pumping on the groundwater quality.