Quality assessment of non-roof harvested rainwater in industrial layouts of Enugu, South East Nigeria

Abstract

AbstractNon-roof harvested rainwater was studied in Enugu industrial layouts of Emene and Iva Valley to determine the quality of the water. The determination was based on physicochemical parameters and concentration of 7 heavy metals, namely copper (Cu), chromium (Cr), nickel (Ni), manganese (Mn), zinc (Zn), lead (Pb) and cadmium (Cd). The physicochemical parameters of the rainwater: pH, colour, turbidity, total dissolved solids, conductivity were determined using Hanna water quality checker, and the anions nitrate, sulphate, chloride and phosphate were analysed in accordance to standard methods. The concentrations of Cu, Cr, Ni, Mn, Zn, Pb and Cd were determined using FS240 Agilent Atomic Absorption Spectrophotometer. The mean values (mg/l) of the metals: Cu, Cr, Ni, Mn, Zn, Pb and Cd in Emene sample are as follows: 0.12 ± 0.01, 0.10 ± 0.02, 0.37 ± 0.02, 0.03 ± 0.01, 0.15 ± 0.01, 0.58 ± 0.11 and 0.17 ± 0.07, while Iva Valley sample recorded 0.08 ± 0.01, 0.04 ± 0.01, 0.82 ± 0.06, 0.09 ± 0.02, 0.26 ± 0.01, 0.48 ± 0.04 and 0.31 ± 0.08, respectively. Some of these values are within or above the standard limit of World Health Organization (WHO) and Nigeria Standard for Drinking Water Quality (NSDWQ). It is important to note that these metals are toxic, persistence and have the potential to bioaccumulate. Therefore, non-roof harvested rainwater is not ready to consume water without some form of treatment. Monitoring, treatment and awareness on the harvesting and use of rainwater should be emphasized.