Free Available Chlorine Residuals for Small Nonpublic Water Supplies

For many years, municipal water treatment facilities have been producing potable water using coliform organisms as an index of water disinfection. In individual water supplies, where constant supervision is unavailable and where the physical and biological character of the raw water fluctuates rapidly, a more stringent standard of disinfection is needed. Superchlorination is recommended to provide a factor of safety for these fluctuations and to reduce the necessary chlorine contact time. This study recommends the use of Coxsackie virus as a criterion of chlorine resistivity in the disinfection of individual water supplies.