A filter made of a nanocomposite of clay – carboximethylchitosan – silver nanoparticles was created to eliminate bacteria and anions in water for human consumption. The silver nanoparticles were obtained by reduction of silver nitrate 1mM, with carboximethyl chitosan at 0.01% and sodium borohydrido 2mM as starter of the reduction. Then the clay filters were made with wood sawdust as the pore maker in a 2:1 proportion; it was molded, dried and sinterized at 800°C for 3 hours. Quickly the filters were impregnated with the colloidal dispersion of carboximethyl chitosan – silver nanoparticles by immersion for 12 hours. Four water sampling points were defined: Huacapuy, La Punta, Plaza de Quilca, Caleta de Quilca. When evaluating the filtering capacity of the filters, it was found that the following were removed: conductivity 84.03% in La Plaza de Quilca, sulfates 85.48% in La Plaza de...