What is the minimum chlorine dosage for new mains?

The minimum chlorine dosage for new mains is established to ensure effective disinfection and to eliminate harmful bacteria and pathogens during the initial treatment of newly installed pipelines. A dosage of 25 mg/L is recommended because it provides sufficient chlorine concentration to achieve a strong disinfecting effect while accounting for potential chlorine demand from organic materials and biofilms that may be present in the new pipelines.

Using a dosage that meets or exceeds this level allows for the adequate protection of water quality and the safety of the water supply. It also helps meet regulatory standards set by health authorities, ensuring that the newly installed mains are suitable for safe drinking water transmission.

Lower dosages may not provide the necessary effectiveness in disinfecting the pipes, which can lead to public health risks from contaminated water. Hence, the choice of 25 mg/L is a well-established guideline within the industry for maintaining water safety and hygiene in newly laid infrastructure.