An Investigation of Nitrification Predictors and Factors in Two Full-scale Drinking Water Distribution Systems
An Investigation of Nitrification Predictors and Factors in Two Full-scale Drinking Water Distribution Systems

Author: Daniel Scott

Publisher:

Published: 2012

Total Pages: 186

ISBN-13:

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The biologically-mediated process of nitrification can occur in chloraminated drinking water distribution systems. In this process, ammonia is oxidized to nitrite by ammonia-oxidizing bacteria (AOB) and archaea (AOA). In complete nitrification, nitrite is further converted to nitrate by nitrite-oxidizers; however, bacterial mediation of this step is less critical as a chemical-oxidation pathway also exists. The initial conversion of ammonia to nitrite is also more critical due to its role in the degradation of the disinfectant residual. Nitrification is affected by factors such as the concentrations of ammonia and total chlorine, the pH of the drinking water, and the temperature. The key consequence of distribution system nitrification is an accelerated decay of the disinfectant residual; it can also lead to increases in nitrite and nitrate, and a potential proliferation of heterotrophic bacteria. The goal of this thesis is to enhance understanding of distribution system nitrification; one aspect to this goal is the evaluation of models for nitrification.

Drinking Water Distribution Systems
Drinking Water Distribution Systems

Author: National Research Council

Publisher: National Academies Press

Published: 2006-12-22

Total Pages: 404

ISBN-13: 0309133955

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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.

Human Pharmaceuticals, Hormones and Fragrances
Human Pharmaceuticals, Hormones and Fragrances

Author: Thomas Ternes

Publisher: IWA Publishing

Published: 2007-01-30

Total Pages: 475

ISBN-13: 1843390930

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The observed concentrations of pharmaceuticals and personal care products (PPCPs) in raw wastewater confirm that municipal wastewater represents the main disposal pathway for the PPCPs consumed in households, hospitals and industry. In sewage treatment plant effluents most PPCPs are still present, since many of these polar and persistent compounds are being removed only partially or, in some cases, not at all. Treated wastewater therefore represents an important point source for PPCPs into the environment. After passing a sewage treatment plant the treated wastewater is mostly discharged into rivers and streams or sometimes used to irrigate fields. If drinking water is produced using resources containing a substantial proportion of treated wastewater (e.g. from river water downstream of communities) the water cycle is closed and indirect potable reuse occurs. Human Pharmaceuticals, Hormones and Fragrances provides an overview of the occurrence, analytics, removal and environmental risk of pharmaceuticals and personal care products in wastewater, surface water and drinking water. The book covers all aspects of the fate and removal of PPCPs in the whole water cycle: consumption and occurrence, analytical methods, the legal background, environmental risk assessment, human and animal toxicology, source control options, wastewater and drinking water treatment as well as indirect reuse. The book presents a summary of the results obtained during the EU project "Poseidon", combined with further expert knowledge on the field, and is written at a level appropriate for professionals involved in management of water resource quality. Professionals in the field including decision makers, engineers and scientists, as well as students entering the field, will find this an invaluable source of information. First comprehensive study on the assessment, fate and removal of pharmaceuticals and personal care products in wastewater and drinking water treatment. Emphasises the importance of micropollutants in the water cycle, provides methods for quantifying their fate and technologies for their removal.

Microbial Growth in Drinking Water Supplies
Microbial Growth in Drinking Water Supplies

Author: Dick van der Kooij

Publisher: IWA Publishing

Published: 2013-09-14

Total Pages: 484

ISBN-13: 1780400403

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Maintaining the microbial quality in distribution systems and connected installations remains a challenge for the water supply companies all over the world, despite many years of research. This book identifies the main concerns and knowledge gaps related to regrowth and stimulates cooperation in future research. Microbial Growth in Drinking Water Supplies provides an overview of the regrowth issue in different countries and the water quality problems related to regrowth. The book assesses the causes of regrowth in drinking water and the prevention of regrowth by water treatment and distribution. Editors: Dirk van der Kooij and Paul W.J.J. van der Wielen, KWR Watercycle Research Institute, The Netherlands

Management of Legionella in Water Systems
Management of Legionella in Water Systems

Author: National Academies of Sciences, Engineering, and Medicine

Publisher: National Academies Press

Published: 2020-02-20

Total Pages: 291

ISBN-13: 030949382X

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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.

Guidelines for Drinking-water Quality
Guidelines for Drinking-water Quality

Author: World Health Organization

Publisher: World Health Organization

Published: 1993

Total Pages: 260

ISBN-13: 9789241545037

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This volume describes the methods used in the surveillance of drinking water quality in the light of the special problems of small-community supplies, particularly in developing countries, and outlines the strategies necessary to ensure that surveillance is effective.