Riverbank filtration for water supply in semi arid environment

ABSTRACT During recent years, Egypt water treatment plants allocated on the banks of River Nile have faced few accidents of hydrocarbon spills into the River which forced the operators to shout down many plants from Aswan to Cairo. Nevertheless, water supply applying the natural and low-cost technique called riverbank filtration "RBF" has been used worldwide. For more than 100 years, RBF that has been used in Europe for public and industrial water supply along Rhine, Elbe, and Danube rivers. In RBF method, the surface water contaminants are removed or degraded as the infiltrating water moves from the river or lake to the abstraction wells. Physical, chemical, and biological treatment processes occur during this technique. In this work, RBF site which is located in east bank of river Nile at Upper Egypt was investigated. This site was established to supply potable water to the construction staff of about 3000 residents, of the new Naga Hammadi Barrage, Qena governorate. It consists of two productive wells of 55 m depth located at 100 m apart from River Nile. No further treatment processes were used except disinfection applying chlorine as calcium hypochlorite. Water samples from abstraction wells were collected for physiochemical and microbiological measurements. Quality analysis of the samples indicates that the produced water using RBF technique complies with allowable standards for drinking purposes. The results have proven RBF effectiveness for water supply from river Nile in Upper Egypt and motivate its integration with tradition plants to secure water supply from Nile during the chemical pollution of Nile