What aspect of water quality does secondary disinfection primarily address?

Secondary disinfection primarily addresses microbial contamination in water systems. This process aims to ensure that water remains free of harmful pathogens after the initial treatment and during distribution to consumers. The importance of secondary disinfection lies in its ability to provide an additional layer of safety, particularly in preventing the regrowth of microorganisms that may occur within the distribution system.

While primary disinfection methods, such as chlorination, ultraviolet (UV) light, or ozonation, effectively eliminate pathogens at the treatment plant, secondary disinfection maintains water quality as it travels through pipes to reach end-users. This is particularly crucial in large or complex distribution networks where standing water may allow for microbial growth. Therefore, the primary goal of secondary disinfection is to safeguard drinking water from microbial hazards, ensuring public health protection.