Improve Building Plumbing Disinfection and Service Line Replacement

T he interface between public water systems and prem- ise plumbing has become more efficient and complex over the past two centuries.Modern infrastructure has delivered treated drinking water to homes, schools, and workplaces for more than a hundred years.However, the final lengths of plumbing present distinct conditions that can introduce or amplify chemical and microbial water quality issues.AWWA's Premise Plumbing Committee provides guidance to address these issues for those who operate, maintain, or supply water to premise plumbing systems.Current initiatives focus on tailoring microbial control strategies for the built environment and developing planning approaches that address uncertainties associated with service line replacement. Updating AWWA C651 for Premise Plumbing DisinfectionPulling from work conducted from 2020 through 2024, AWWA published Disinfecting Building Potable Water Plumbing in New or Repaired Systems, a technical report providing procedural guidance for building plumbing.The report addresses long-standing misuse of AWWA Standard C651, Disinfecting Water Mains, in building environments.In fall 2024, the AWWA Standards Council approved a proposal to revise C651 to incorporate this guidance.A subcommittee, chaired by Alex Mofidi, is working with the C651 committee and Standards Council to integrate the material into the standard.Mofidi and William Rhoads presented an update at AWWA's 2026 Annual Conference and Exposition, held in June in Washington, D.C.The addendum applies to disinfection of premise plumbing in new, repaired, or renovated buildings; it does not address remediation of existing systems.Contributors represent the same sectors in which the guidance will be applied and aim to improve clarity for contractors and health departments overseeing disinfection.The addendum outlines procedures for the following: Layout imagery by Kadmy/stock.adobe.