ABSTRACT

Due to scarcity of potable water, rainwater harvesting from rooftop has been favoured as an alternative source of water supply by most rural communities in Nigeria. This study investigated the physicochemical characteristics of rainwater harvested from four different rooftop sheets in Ikole-Ekiti, Ekiti State. Samples were collected from four different iron sheets at the peak of raining season in the .month of August, 2018. Parameters investigated include pH, TDS, Turbidity, Conductivity, Alkalinity, Total Hardness, Ca, Fe, Pb,Zn, Al,'Cu, Mg, Na and K Data obtained were subjected to mean and statistical analysis. The results showed that mean values of harvested rainwater from all sampled rooftops are slightly basic. All measured parameters were high in Aluminum and Coated pans but does not exceed the WHO water quality standards followed by Galvanized zinc rooftop while samples from painted pan had the least. The result shows that the physicochemical parameters ranges from 8.03-9.17 (pH), 0.47- 3.17NTU (Turbidity), 56.20-170.43μs/cm (EC), 30.2-50.53mg/L (TDS), 18.56-27.58mg/L (Alkalinity), 19.94-24.08mg/L (Total Hardness), 8;67-14.93mg/L (Sulphate), 4.11-1l.67mg/L (Chloride), 0-4.62mg/L (Zn), 7.11-11.Bmg/L (Calcium), 0.07-l.56mg/L (Al), 0.0l-0.02mg/L (Cu), 9.41-21.33mg/L (Mg), 29.04-40.35mg/L (Na) were all within permissible water quality standard as recommended by World Health Organizations (WHO) except ,for the presence of particles (Fe) 0.l-0.29mg/L which were found above the permissible limit in Galvanized Zinc pan. Pearson Correlation Matrix of physicochemical properties conducted indicated a strong positive correlation between Zinc and Iron which emphasizes common pathway and origin. The water samples were assessed using Water Quality Index (WQI), the WQI for painted pan, aluminium pan, galvanized zinc pan, and coated pan were 3.296, 1.335, 6.078 (highest) and 2.629 respectively indicating excellent water quality. It can be concluded that harvested rainwater in the area can be used for domestic purpose with minimum treatment.