The Effectiveness of Disinfectant Residuals in the Distribution System
As part of the revision of the Total Coliform Rule, USEPA published a series of issue papers to present available information on topics relevant to possible TCR revisions. The objectives of the issue papers were to review the available data, information and research regarding the potential public health risks associated with the distribution system issues, and where relevant identify areas in which additional research may be warranted. The issue papers serve as background material for EPA, expert and stakeholder discussions. The papers only present available information and do not represent Agency policy. Some of the papers were prepared by parties outside of EPA; EPA does not endorse those papers, but is providing them for information and review.
The Effectiveness of Disinfectant Residuals in the Distribution System
This paper reviews the existing literature, research and information to inform the effectiveness of disinfectant residuals in the distribution system. The paper focuses on the effectiveness of residuals to control biofilm, indicate distribution system upsets, and inactivate contaminants that may enter the distribution system. The paper reviews disinfection CT (concentration and contact time) for a range of pathogens under conditions that may mimic those in distribution systems.