What is the main purpose of maintaining a chlorine residual in a treatment plant?

The main purpose of maintaining a chlorine residual in a treatment plant is to ensure effective disinfection. Chlorine acts as a powerful disinfectant used to eliminate harmful microorganisms such as bacteria, viruses, and protozoan cysts in water. By maintaining an appropriate level of chlorine residual in the distribution system, it ensures that any pathogens that might enter the water after treatment are effectively inactivated, providing safer drinking water to consumers.

This residual also plays a role in the overall treatment process by providing a constant level of protection as water travels through distribution systems, helping to uphold water quality and safety. Keeping a proper chlorine residual is not solely an evaluation tool; while assessing plant performance is important, it does not serve the fundamental role of protecting public health as disinfection does.

In terms of cost management and algae control, while maintaining a chlorine residual might indirectly influence chemical costs and help in managing algae growth in some cases, these are not the primary goals of its maintenance within a treatment facility.