Hydrochemical Characteristics of Groundwater in Siwa Oasis, Egypt. Part I. Significance of the Situation Groundwater Resources and Future Outlook

This research, carried out with the objective of developing water management strategies in Siwa Oasis to ensure its sustainable development. Siwa Oasis (1000 km2) is today suffering an excessive rise in the subsoil water levels. The rate of groundwater rises from 1.33 to 4.6 cm/ year. Consequently, the fertile soils are subjected to deterioration and salinization. This is proposing and testing chain water management scenarios that makes use of suitable water (multiple reuses) before it reaches the last disposal point to increase the cultivated area (17000 feddans). So, this paper carried out the hydrogeochemical groundwater study based on the results of the chemical analysis of groundwater samples collected. To determine the evolution of groundwater resources through different analysis of water, such as total dissolved salts (TDS) and total hardness in two aquifers, Nubian sandstone and fractured dolomite limestone. The results show, the salinity of groundwater representing the area changed from fresh to saline groundwater, 168.8 to 7472.8 mg/l and total hardness from soft to hard, 30.7 to 1829.7mg/l as CaCO3