EPA is proposing to revise a national primary drinking water regulation to achieve greater public health protection against waterborne pathogens in the distribution systems of public water systems, according to an agency press release. Waterborne pathogens can cause a variety of illnesses with symptoms such as acute abdominal discomfort or in more extreme cases, kidney failure, hepatitis or chronic concerns.

EPA is proposing to revise the 1989 Total Coliform Rule to incorporate improvements recommended by a federal advisory committee that included representatives from a broad range of stakeholder groups, including public health and public interest groups, environmental groups, state drinking water agencies and drinking water utilities. EPA used a transparent, collaborative process with stakeholders to help make this regulation more effective.

The revised rule will better protect people from potential exposure to dangerous microbes because it requires water systems to take action when monitoring results indicate that contamination or a pathway to contamination may be present. Water utilities are required to regularly monitor for microbial contamination in the distribution system. Although microbes detected in monitoring are not necessarily pathogens themselves, the detection can indicate that there is a pathway that would allow pathogens to enter the system, such as a water main break or an opening in a storage tank. Under the proposed rule, when monitoring results are positive, systems must find and fix any pathways leading to microbial risk.

The proposal also provides incentives for better system operation by improving the criteria for public water systems to qualify for and stay on reduced monitoring, which provides an opportunity to reduce system burden. In addition, the proposed rule updates conditions that will trigger public notices to better represent the relative health threat identified. It also makes the wording required in these public notices more clear. These changes increase consumer confidence in the safety of their water and understanding of the risks when contamination occurs.

EPA is seeking public comment on this proposed rule for 60 days following publication in the Federal Register.