The impact of river sand mining and waste management on the Volta Lake: A case study of Asutsuare

The safety of drinking water is becoming more crucial as the world's population is increasing and anthropogenic activities which pollute water resources are intensifying. This study was carried out between June and August of 2022 to determine the physicochemical and microbial parameters of the Volta Lake at Asutsuare due to sand mining activities and to evaluate how well coconut husk biochar could remove these contaminants. Water samples were taken from one meter below the surface at the upstream, midstream (sand mining site) and downstream once a week for three months. Water samples from the midstream were passed through a coconut husk biochar column to determine its ability to remove pollutants in the water samples. Compared to the upstream, there was a significant difference (p < 0.05) in colour, turbidity, iron, manganese, biochemical oxygen demand, chemical oxygen demand, total coliform and total suspended solids from the water sampled from the midstream and downstream sites. Moreover, these values also exceeded the WHO guidelines. There were no significant differences (p > 0.05) between the midstream, the upstream and downstream sampling sites for the following parameters: zinc, lead, copper, conductivity, TDS, temperature, faecal coliform, Escherichia coli and pH. Biochar from coconut husk was used once and seems to be a highly effective sorbent for removing pollutants from water samples (>70 % removal efficiency).