What is the minimum chlorine residual required at the entrance to a water distribution system?

What is the minimum chlorine residual required at the entrance to a water distribution system?

• A. 0.2 mg/L
• B. 2 mg/L
• C. 2.5 mg/L
• D. 4 mg/L

Answer: (A)

The minimum chlorine residual required at the entrance to a water distribution system is set to ensure adequate disinfection and to provide a protective barrier against pathogens as the water travels through the distribution system. A residual level of 0.2 mg/L is often recognized as the minimum standard needed to maintain some degree of disinfection while minimizing the potential for taste and odor issues that higher concentrations may cause. Chlorine residual is essential for controlling microbial growth and preventing waterborne diseases, making it a critical parameter in water quality management. Hence, maintaining a minimum of 0.2 mg/L assures that the water remains safe for consumption as it moves through the system. This level strikes a balance between effective disinfection and palatability, which is why it is often established as a baseline in water treatment guidelines.

The minimum chlorine residual required at the entrance to a water distribution system is set to ensure adequate disinfection and to provide a protective barrier against pathogens as the water travels through the distribution system. A residual level of 0.2 mg/L is often recognized as the minimum standard needed to maintain some degree of disinfection while minimizing the potential for taste and odor issues that higher concentrations may cause.

Chlorine residual is essential for controlling microbial growth and preventing waterborne diseases, making it a critical parameter in water quality management. Hence, maintaining a minimum of 0.2 mg/L assures that the water remains safe for consumption as it moves through the system. This level strikes a balance between effective disinfection and palatability, which is why it is often established as a baseline in water treatment guidelines.