Disinfection of microbially contaminated water is an important part of water purification, aiming to inactivate pathogenic microorganisms in water. Silver nanoparticles have attracted tremendous interest for water disinfection because of their antibacterial efficiency. This study focuses on the use of garnet sand coated with silver-graphite composite in deactivating waterborne microbes. Graphite was purified by acid leaching, followed by surface modification with conc. HNO3. The silver-graphite composite material (SVG) was synthesized using AgNO3 as a precursor and trisodium citrate as a reducing agent. SVG was coated around garnet sand with the assistance of three types of clays namely montmorillonite, red clay, and kaolinite. Garnet sand was directly coated with silver nanoparticles to compare the durability and antibacterial efficiency. Garnet sand coated with SVG using red clay (75%) and montmorillonite (75%) showed a higher percentage coating than that used with kaolinite (25%). The antibacterial activity of coated garnet was tested using Escherichia coli. The results revealed that all coated garnet sand samples were able to decrease the concentration of E. coli from water, and no effect was observed from raw garnet sand. The antibacterial efficiencies were (13-70%), (15–57%), (38-67%) for kaolinite, red clay, and montmorillonite coated garnet sand, respectively. The garnet sand coated with silver nanoparticles showed the highest efficiency (96-100%) with the lowest percentage of coating. According to the results obtained, garnet sand coated with SVG using montmorillonite showed the highest antibacterial activity and the highest percentage of the coating. Therefore, this study, suggests that the filter system with the garnet sand coated with SVG using clays can be used as a potentially cost-effective alternative filtration medium for the disinfection of water.