Water Quality Assessment of the Nile Delta Lagoons

Abstract

Nile Delta Lagoons have been formed 7000 years before the present. The lagoons were aqua-cultural and ecological keystones for the early Egyptian agricultural civilization. The water quality of Nile Delta Lagoons has been deteriorated with the economic development, population rapid increase, and the related industrialization, which exert high pressure on the surrounding environment. The 4 lagoons (1) Maryut, (2) Edku, (3) Burullus, and (4) Manzala are large is surface area, shallow in depth and located on the Nile Delta that receive great amounts of agricultural drainage, sewage, and industrial effluents before discharging into the Mediterranean Sea. The aim of this study is to monitor and assess the water and sediment quality of the lagoons. In light of this assessment, it was found that excessive nutrients are discharged into these lagoons causing severe eutrophication. In addition, relatively low values of dissolved oxygen were recorded causing fish mortality in the lagoons which amplifies in summer as the temperature increases. The article also examined the physical and biological parameters in addition to the chemical concentration of trace metals (Zn, Fe, Pb, Mn, Cr, and Cd) in the water and sediment samples that were collected from the 4 lagoons. High values of biological oxygen demand, chemical oxygen demand, total coliform, fecal coliform, fecal streptococci, ammonia (NH3), total nitrogen, and total phosphorus were recorded. In addition, high concentrations of trace metals were found in the water and sediments of the 4 lagoons.