Water Quality Evaluation of Drinking Water Sources within Kyebando Ward using Water Quality Index.
Abstract
Despite the existence of public water points in peri-urban areas, the quality of water remains questionable and has raised concerns about its suitability for human consumption. The study aimed to identify the suitability of water points for drinking purposes in Kyebando ward using the water quality index (WQI) approach. Preliminary activities involved obtaining community entries from Directorate of Public Health KCCA and LC 1 chairpersons, randomly selecting water points, designing surveys and acquiring testing kits. The cross-sectional study employed water quality analysis, a questionnaire survey, and direct observation conducted in February and March 2023. The water quality of randomly selected water points collected were analyzed in the laboratory and associated factors investigated. A total of 97 water points were sampled and on-site testing using a multiparameter meter and pool testing kit was used to measure pH, turbidity, Temperature, EC and FCR. Additionally, 50ml water samples were collected and transported to the laboratory within 8 hours and assessed for E. coli using membrane filtration method. Quality control measures were observed and summary statistics were computed using R-Studio and compared to the recommended UNBS and WHO drinking water standards. Spatial distribution mapping using QGIS software was performed, followed by the computation of WQI. The physiochemical quality of the different water points generally fell within an acceptable UNBS and WHO range, except for pH and EC in spring water. Among the water points, E. coli was present in non-tap samples i.e., 66.7% protected springs, 71.4% unprotected springs, 50% boreholes, 20% rainwater harvesting tanks, 60% storage tanks and 60% other source types whereas tap samples exhibited less counts of E. coli. The spatial distribution mapping facilitated the identification of water points with safe and unsafe water for consumption, as per the drinking water standards. Based on the WQI, tap water samples exhibited excellent drinking water quality suitable for human consumption compared to non-tap water samples from protected springs, unprotected springs, boreholes and rainwater. Sanitary inspections indicated that higher FCR concentrations significantly influenced E. coli disinfection. Sanitary risk assessment revealed that 23.7% of the studied water points had both no risk and medium risk, 32% had low risk, 13.4% had high risk and 7.2% had very high risk of contamination. Hence, water from certain locations was unfit for human consumption, emphasizing the need for improved water quality management plans involving local community members and water supply utilities such NWSC to continuously monitor water quality and mitigate public health threat to the residents of Kyebando.