AWWA C601-81 PDF Download

The AWWA C601-81 Standard for Disinfecting Water Mains is a historical standard that was first approved in 1947 and underwent its last revision in 1981. It was subsequently approved by ANSI in August of that same year. This standard outlines the necessary procedures for disinfecting both new and repaired water mains. New water mains must be disinfected prior to being put into service, while any water mains that have been taken out of service for maintenance or repair work that could potentially contaminate the water supply must also be disinfected before being returned to service.

The standard provides comprehensive guidance on a range of topics related to disinfecting water mains. It includes information on references, forms of chlorine disinfection (such as liquid chlorine, sodium hypochlorite, and calcium hypochlorite), basic disinfection procedures, preventive and corrective methods during construction, cleaning and swabbing techniques, different methods of chlorination (such as the tablet method, continuous feed method, and slug method), final flushing procedures, bacteriological testing, special conditions that may impact disinfection procedures, and redisinfection protocols. The standard also includes appendices that offer guidance on chlorine residual testing and the proper disposal of heavily chlorinated water.