Hydrogeochemical assessment and stable isotopic investigation of groundwater in the New Delta -Rodh Al-Farag–El-Dabaa Pivot Road, Western Desert, Egypt

Abstract The current research aims to examine the Moghra groundwater hydrogeochemistry and assess its suitability for irrigation demands using water quality, descriptive statistical analysis, and physicochemical parameters, in addition to identifying the Moghra aquifer’s major recharge sources utilizing stable isotopes in the New Delta project, Western Desert, Egypt. The Moghra aquifer consists of variegated sandstone with frequent shale intercalations, and the groundwater is found under unconfined to semi-confined conditions. Seventy groundwater samples were gathered during November 2023. The groundwater salinity varies between 341 mg/L and 5129 mg/L. The geochemical processes governing the groundwater chemistry were inferred utilizing Gibbs, Biplots, and Piper trilinear diagrams. The saturation index of Moghra groundwater samples indicates that the majority of samples (~ 80%) are supersaturated with calcite, aragonite, and dolomite. While all groundwater samples are undersaturated with respect to anhydrite, gypsum and halite. The groundwater is influenced by ion exchange, silicate and carbonate weathering. The main water type is alkaline water with prevailing sulfate and chloride. Geochemical and isotopic investigations disclose that the Moghra groundwater was primarily of meteoric origin with a slight influence of evaporation. The groundwater suitability for irrigation purposes was assessed utilizing various parameters as; Sodium Percent, Permeability Index, Sodium Adsorption Ratio, Kelley Index, Potential Salinity, Magnesium Hazard, Corrosive Ratio and Residual Sodium Carbonate, which demonstrate that all the studied groundwater samples are adequate for irrigation utilities, however special management may be needed for controlling salinity as cultivating crops with good salt tolerance, good drainage, high leaching and the addition of organic matter.