Impact of Distribution System Water Quality on Disinfection Efficacy

Impact of Distribution System Water Quality on Disinfection Efficacy
Author: Hé́lène Baribeau
Publisher: American Water Works Association
Total Pages: 324
Release: 2005
Genre: Water
ISBN: 1583214100

Assesses the impact of dynamic water quality conditions in the distribution system on the inactivation of microorganisms in bulk water. Addresses questions about the usefulness of maintaining a secondary residual and the target level to be maintained. Bridges research related to distribution system water quality with that of microbial inactivation.

Drinking Water Distribution Systems

Drinking Water Distribution Systems
Author: National Research Council
Publisher: National Academies Press
Total Pages: 404
Release: 2006-12-22
Genre: Science
ISBN: 0309133955

Protecting and maintaining water distributions systems is crucial to ensuring high quality drinking water. Distribution systems-consisting of pipes, pumps, valves, storage tanks, reservoirs, meters, fittings, and other hydraulic appurtenances-carry drinking water from a centralized treatment plant or well supplies to consumers' taps. Spanning almost 1 million miles in the United States, distribution systems represent the vast majority of physical infrastructure for water supplies, and thus constitute the primary management challenge from both an operational and public health standpoint. Recent data on waterborne disease outbreaks suggest that distribution systems remain a source of contamination that has yet to be fully addressed. This report evaluates approaches for risk characterization and recent data, and it identifies a variety of strategies that could be considered to reduce the risks posed by water-quality deteriorating events in distribution systems. Particular attention is given to backflow events via cross connections, the potential for contamination of the distribution system during construction and repair activities, maintenance of storage facilities, and the role of premise plumbing in public health risk. The report also identifies advances in detection, monitoring and modeling, analytical methods, and research and development opportunities that will enable the water supply industry to further reduce risks associated with drinking water distribution systems.

Drinking Water Distribution Systems

Drinking Water Distribution Systems
Author: National Research Council
Publisher: National Academies Press
Total Pages: 405
Release: 2007-01-22
Genre: Science
ISBN: 0309103061

Protecting and maintaining water distributions systems is crucial to ensuring high quality drinking water. Distribution systems-consisting of pipes, pumps, valves, storage tanks, reservoirs, meters, fittings, and other hydraulic appurtenances-carry drinking water from a centralized treatment plant or well supplies to consumers' taps. Spanning almost 1 million miles in the United States, distribution systems represent the vast majority of physical infrastructure for water supplies, and thus constitute the primary management challenge from both an operational and public health standpoint. Recent data on waterborne disease outbreaks suggest that distribution systems remain a source of contamination that has yet to be fully addressed. This report evaluates approaches for risk characterization and recent data, and it identifies a variety of strategies that could be considered to reduce the risks posed by water-quality deteriorating events in distribution systems. Particular attention is given to backflow events via cross connections, the potential for contamination of the distribution system during construction and repair activities, maintenance of storage facilities, and the role of premise plumbing in public health risk. The report also identifies advances in detection, monitoring and modeling, analytical methods, and research and development opportunities that will enable the water supply industry to further reduce risks associated with drinking water distribution systems.

Management of Legionella in Water Systems

Management of Legionella in Water Systems
Author: National Academies of Sciences, Engineering, and Medicine
Publisher: National Academies Press
Total Pages: 291
Release: 2020-02-20
Genre: Medical
ISBN: 030949382X

Legionnaires' disease, a pneumonia caused by the Legionella bacterium, is the leading cause of reported waterborne disease outbreaks in the United States. Legionella occur naturally in water from many different environmental sources, but grow rapidly in the warm, stagnant conditions that can be found in engineered water systems such as cooling towers, building plumbing, and hot tubs. Humans are primarily exposed to Legionella through inhalation of contaminated aerosols into the respiratory system. Legionnaires' disease can be fatal, with between 3 and 33 percent of Legionella infections leading to death, and studies show the incidence of Legionnaires' disease in the United States increased five-fold from 2000 to 2017. Management of Legionella in Water Systems reviews the state of science on Legionella contamination of water systems, specifically the ecology and diagnosis. This report explores the process of transmission via water systems, quantification, prevention and control, and policy and training issues that affect the incidence of Legionnaires' disease. It also analyzes existing knowledge gaps and recommends research priorities moving forward.

Fundamentals and Control of Nitrification in Chloraminated Drinking Water Distribution Systems (M56)

Fundamentals and Control of Nitrification in Chloraminated Drinking Water Distribution Systems (M56)
Author: AWWA Staff
Publisher: American Water Works Association
Total Pages: 288
Release: 2011-01-12
Genre: Denitrification
ISBN: 1613000294

This brand new manual was written because of the increased use of chloramine as a residual disinfectant in drinking water distribution systems and the ubiquitous presence of nitrifying bacteria in the environment. Chapters cover background information on the occurrence and microbiology of nitrification in various water environments and provide current practical approaches to nitrification prevention and response. This manual provides a compendium of the current state-of-the-art knowledge, however with quickly developing new advances in nitrification, more writings will be forthcoming. Each chapter can be read independently.

Long-Term Effects of Disinfection Changes on Water Quality

Long-Term Effects of Disinfection Changes on Water Quality
Author: John E. Dyksen
Publisher: American Water Works Association
Total Pages: 316
Release: 2007
Genre: Water
ISBN: 1583215352

In response to many U.S. water utilities that are considering changing disinfectants from chlorine to alternative disinfectants, this research has been undertaken to gain knowledge of long-term effects.

Identifying Future Drinking Water Contaminants

Identifying Future Drinking Water Contaminants
Author: National Research Council
Publisher: National Academies Press
Total Pages: 277
Release: 1999-09-30
Genre: Nature
ISBN: 0309064325

With an increasing population, use of new and diverse chemicals that can enter the water supply, and emergence of new microbial pathogens, the U.S. federal government is faced with a regulatory dilemma: Where should it focus its attention and limited resources to ensure safe drinking water supplies for the future? Identifying Future Drinking Water Contaminants is based on a 1998 workshop on emerging drinking water contaminants. It includes a dozen papers that were presented on new and emerging microbiological and chemical drinking water contaminants, associated analytical and water treatment methods for their detection and removal, and existing and proposed environmental databases to assist in their proactive identification and regulation. The papers are preceded by a conceptual approach and related recommendations to EPA for the periodic creation of future Drinking Water Contaminant Candidate Lists (CCLsâ€"produced every five yearsâ€"include currently unregulated chemical and microbiological substances that are known or anticipated to occur in public water systems and that may pose health risks).

Coliforms in Distribution Systems

Coliforms in Distribution Systems
Author: Graham A. Gagnon
Publisher: American Water Works Association
Total Pages: 164
Release: 2007
Genre: Drinking water
ISBN: 1583215417

The objective of this project is to understand the potential mechanisms of antimicrobial resistance of E. coli and opportunistic pathogens under disinfection conditions. The project involves molecular techniques to understand genetic changes in biofilm and suspended bacteria in response to different disinfectant conditions. It examines the effects of using single chemical disinfectants (free chlorine, chloramines, and chlorine dioxide) compared with UV light pretreatment, as well as the impact of pipe material (polycarbonate or cast iron) and E. coli mutations. Field studies include both surface water and groundwater.

Global Issues in Water, Sanitation, and Health

Global Issues in Water, Sanitation, and Health
Author: Institute of Medicine
Publisher: National Academies Press
Total Pages: 328
Release: 2009-10-25
Genre: Medical
ISBN: 0309138728

As the human population grows-tripling in the past century while, simultaneously, quadrupling its demand for water-Earth's finite freshwater supplies are increasingly strained, and also increasingly contaminated by domestic, agricultural, and industrial wastes. Today, approximately one-third of the world's population lives in areas with scarce water resources. Nearly one billion people currently lack access to an adequate water supply, and more than twice as many lack access to basic sanitation services. It is projected that by 2025 water scarcity will affect nearly two-thirds of all people on the planet. Recognizing that water availability, water quality, and sanitation are fundamental issues underlying infectious disease emergence and spread, the Institute of Medicine held a two-day public workshop, summarized in this volume. Through invited presentations and discussions, participants explored global and local connections between water, sanitation, and health; the spectrum of water-related disease transmission processes as they inform intervention design; lessons learned from water-related disease outbreaks; vulnerabilities in water and sanitation infrastructure in both industrialized and developing countries; and opportunities to improve water and sanitation infrastructure so as to reduce the risk of water-related infectious disease.