Water quality status and pollution indices of Wadi El-Rayan lakes, El-Fayoum, Egypt

Abstract

Wadi El-Rayan lakes are a crucial source of irrigation water and fisheries in El-Fayoum Governorate of Egypt. It is part of the Wadi El-Rayan Protected Area (WEPA) about 125 km Southwest of Cairo. The present study was carried out to assess the present status of the lakes’ water quality, especially after the increasing of un-controlled economic activities within its boundaries. The results demonstrated that the upper lake water may be suitable for irrigation utilization, and the water quality is categorized as fair (WQI = 67). The two lakes are classified as marginal for aquatic life habitat, with (WQI = 52 and 61) for the upper and lower lakes, respectively. Eight heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were studied to evaluate the metal pollution in the lakes’ water. Pollution index (PI) and metal index (MI) revealed that the water of the two lakes suffers from a different degree of metal contamination, especially for aquatic life utilization. In addition, the progressive increasing of salinity in the second lake enhances the remarkable deterioration of the lake aquatic environment that may restore the dramatic transformation story of Qarun lake.