Assessment of Roof Harvested Rainwater in Parts of Anambra State for Environmental Pollution Monitoring

Questions have been raised about the quality of roof harvested rainwater which has been shown to be temporally and spatially variable and at times not in compliance with drinking water guidelines. This study is therefore an investigation on the quality of roof harvested rainwater consumed by rural communities in parts of Anambra State Nigeria. The physico-chemical and microbiological parameters of the rainwater samples collected in the study area were analyzed with the view of determining the level of contamination as a result of anthropogenic activities in the study area. Roof harvested rainwater were collected from three stations, and a free-fall harvested rainwater sample was used as a control. The result shows that the physico-chemical parameters were all within permissible water quality standard as recommended by National Agency for Food and Drug Administration Control (NAFDAC) except for the presence of particles and for the micro-biological properties which were found quite unsatisfactory. Pearson Correlation Matrix of physico-chemical 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 the station 1, 2 and 3 were 71.68%, 60.19%, and 77.55% respectively. Low-cost microbial disinfection such as solar disinfection and pre-filtration or otherwise the proper maintenance of the entire Rain Water Harvesting (RWH) system could make the harvested roof rainwater potable for the study area.