An extremely efficient bactericidal filter paper is developed that is capable of removing 99.99999% of Escherichia coli bacteria in a simple filtration process. The novel approach utilizes two active bactericidal components: a bactericidal agent, triclosan, which acts synergistically with a cationic polyelectrolyte binder with antibacterial properties. The biocide is incorporated into the block copolymer micelles attached to the cellulose fibers via the cationic polyelectrolyte. As the water containing the bacteria is passed by gravity through the filter paper, the bactericidal agents are transferred to the bacteria through collisions with the micelles or coated fibers. A synergy between the biocide and the polyelectrolyte is responsible for the extremely high efficiency in deactivating the bacteria. The filtered water is free of biocide other than that transported by the dead bacteria. This technology represents a very simple approach to provide potable water under a wide range of primitive conditions.