Assessment of water quality in the shores of the Nile River islands, Egypt: Chemical and microbiological analysis

The Nile River is the primary source of freshwater in Egypt. The water quality of seven permanent Nile Islands (three upstream in Aswan and four downstream in Cairo) was assessed using a variety of chemical, physical, and bacteriological variables and indices. A total of 84 water samples were collected from the shores of the Nile Islands during the winter and summer seasons. Standard methods were used to analyze the water samples for various variables, including nutrients, bacteria, and heavy metals. A significant difference was found in most variables, especially heavy metals, between the shores of the Cairo Islands and the Aswan Islands. On all shores, Cu, Zn, Co, Cr, Pb, and Cd levels exceeded the acceptable limits set by international standards for aquatic life protection. The distribution patterns of these variables are strongly influenced by various island activities. The average water quality index for the Nile shores at various islands ranged from 79 to 90, indicating suitable water quality for aquatic organisms. The Nile chemical pollution index classified the water quality at islands shores as slightly polluted throughout the dry season. However, the heavy metal pollution indices consistently showed some degree of metal contamination on the shores of the Cairo Islands. Although the water on the Nile shores was not severely polluted, continuous water quality monitoring is important, especially given the potential decrease in Egypt's share of the Nile water, increase in contaminants, and changes in land use on the islands following the completion of the Grand Ethiopian Renaissance Dam.