A committee, formed by the Water Science and Technology Board, will conduct a study of water quality issues associated with public water supply distribution systems and their potential risks to consumers. The study will consider, but not be limited to, aspects of distribution systems such as cross connections and backflow, pressure transients, nitrification, permeation and leaching, repair and replacement of water mains, aging infrastructure, and microbial growth. The proposed activity will:1?As background and based on available information, identify trends relevant to the deterioration of drinking water in water supply distribution systems.2?Identify and prioritize issues of greatest concern for distribution systems based on review of published material.3?Focusing on the highest priority issues as revealed by task #2, (a) evaluate different approaches to characterization of public health risks posed by water-quality deteriorating events or conditions that may occur in public water supply distribution systems; and (b) identify and evaluate the effectiveness of relevant existing codes and regulations and identify general actions, strategies, performance measures, and policies that could be considered by water utilities and other stakeholders to reduce the risks posed by water-quality deteriorating events or conditions. Case studies, either at state or utility level, where distribution system control programs (e.g., Hazard Analysis and Critical Control Point System, cross connection control, etc.) have been successfully designed and implemented will be identified and recommendations will be presented in their context.4?Identify advances in detection, monitoring and modeling, analytical methods, information needs and technologies, research and development opportunities, and communication strategies that will enable the water supply industry and other stakeholders to further reduce risks associated with public water supply distribution systems. The study will evaluate its recommendations in the context of case examples revealed by the task #3 effort (to identify relevant case studies). A Final Report will be issued at the end of the project in approximately 22 months.Sponsor: U.S. Environmental Protection AgencyThe approximate starting date for the project is 08/01/2004.