Author: Gil F. Crozes
Publisher: American Water Works Association
ISBN: 1583210253
Category : Water
Languages : en
Pages : 208
Book Description
Evaluating Biological Regrowth in Distribution Systems
Author: Gil F. Crozes
Publisher: American Water Works Association
ISBN: 1583210253
Category : Water
Languages : en
Pages : 208
Book Description
Publisher: American Water Works Association
ISBN: 1583210253
Category : Water
Languages : en
Pages : 208
Book Description
Drinking Water Distribution Systems
Author: National Research Council
Publisher: National Academies Press
ISBN: 0309133955
Category : Science
Languages : en
Pages : 404
Book Description
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.
Publisher: National Academies Press
ISBN: 0309133955
Category : Science
Languages : en
Pages : 404
Book Description
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.
Assessing and Controlling Bacterial Regrowth in Distribution Systems
Author:
Publisher: American Water Works Association
ISBN: 0898674905
Category : Disinfection and disinfectants
Languages : en
Pages : 268
Book Description
Publisher: American Water Works Association
ISBN: 0898674905
Category : Disinfection and disinfectants
Languages : en
Pages : 268
Book Description
Bacterial Growth on Surfaces as a Method for Assessment of Biological Stability of Drinking Water
Water Quality Decay and Pathogen Survival in Drinking Water Distribution Systems
Author: Precious Thabisile Biyela
Publisher:
ISBN:
Category : Drinking water
Languages : en
Pages : 176
Book Description
The deterioration of drinking-water quality within distribution systems is a serious cause for concern. Extensive water-quality deterioration often results in violations against regulatory standards and has been linked to water-borne disease outbreaks. The causes for the deterioration of drinking water quality inside distribution systems are not yet fully understood. Mathematical models are often used to analyze how different biological, chemical, and physical phenomena interact and cause water quality deterioration inside distribution systems. In this dissertation research I developed a mathematical model, the Expanded Comprehensive Disinfection and Water Quality (CDWQ-E) model, to track water quality changes in chloraminated water. I then applied CDWQ-E to forecast water quality deterioration trends and the ability of Naegleria fowleri (N.fowleri), a protozoan pathogen, to thrive within drinking-water distribution systems. When used to assess the efficacy of substrate limitation versus disinfection in controlling bacterial growth, CDWQ-E demonstrated that bacterial growth is more effectively controlled by lowering substrate loading into distribution systems than by adding residual disinfectants. High substrate concentrations supported extensive bacterial growth even in the presence of high levels of chloramine. Model results also showed that chloramine decay and oxidation of organic matter increase the pool of available ammonia, and thus have potential to advance nitrification within distribution systems. Without exception, trends predicted by CDWQ-E matched trends observed from experimental studies. When CDWQ-E was used to evaluate the ability N. fowleri to survive in finished drinking water, the model predicted that N. fowleri can survive for extended periods of time in distribution systems. Model results also showed that N. fowleri growth depends on the availability of high bacterial densities in the 105 CFU/mL range. Since HPC levels this high are rarely reported in bulk water, it is clear that in distribution systems biofilms are the prime reservoirs N. fowleri because of their high bacterial densities. Controlled laboratory experiments also showed that drinking water can be a source of N. fowleri, and the main reservoir appeared to be biofilms dominated by bacteria. When introduced to pipe-loops N. fowleri successfully attached to biofilms and survived for 5 months.
Publisher:
ISBN:
Category : Drinking water
Languages : en
Pages : 176
Book Description
The deterioration of drinking-water quality within distribution systems is a serious cause for concern. Extensive water-quality deterioration often results in violations against regulatory standards and has been linked to water-borne disease outbreaks. The causes for the deterioration of drinking water quality inside distribution systems are not yet fully understood. Mathematical models are often used to analyze how different biological, chemical, and physical phenomena interact and cause water quality deterioration inside distribution systems. In this dissertation research I developed a mathematical model, the Expanded Comprehensive Disinfection and Water Quality (CDWQ-E) model, to track water quality changes in chloraminated water. I then applied CDWQ-E to forecast water quality deterioration trends and the ability of Naegleria fowleri (N.fowleri), a protozoan pathogen, to thrive within drinking-water distribution systems. When used to assess the efficacy of substrate limitation versus disinfection in controlling bacterial growth, CDWQ-E demonstrated that bacterial growth is more effectively controlled by lowering substrate loading into distribution systems than by adding residual disinfectants. High substrate concentrations supported extensive bacterial growth even in the presence of high levels of chloramine. Model results also showed that chloramine decay and oxidation of organic matter increase the pool of available ammonia, and thus have potential to advance nitrification within distribution systems. Without exception, trends predicted by CDWQ-E matched trends observed from experimental studies. When CDWQ-E was used to evaluate the ability N. fowleri to survive in finished drinking water, the model predicted that N. fowleri can survive for extended periods of time in distribution systems. Model results also showed that N. fowleri growth depends on the availability of high bacterial densities in the 105 CFU/mL range. Since HPC levels this high are rarely reported in bulk water, it is clear that in distribution systems biofilms are the prime reservoirs N. fowleri because of their high bacterial densities. Controlled laboratory experiments also showed that drinking water can be a source of N. fowleri, and the main reservoir appeared to be biofilms dominated by bacteria. When introduced to pipe-loops N. fowleri successfully attached to biofilms and survived for 5 months.
Distribution System Performance Evaluation
Author: Arun K. Deb
Publisher: American Water Works Association
ISBN: 1613001665
Category : Technology & Engineering
Languages : en
Pages : 144
Book Description
Publisher: American Water Works Association
ISBN: 1613001665
Category : Technology & Engineering
Languages : en
Pages : 144
Book Description
Development of Distribution System Water Quality Optimization Plans
Author: Melinda J. Friedman
Publisher: American Water Works Association
ISBN: 1583213880
Category : Water
Languages : en
Pages : 256
Book Description
CD-ROM contains chapter 4 and appendices A & B.
Publisher: American Water Works Association
ISBN: 1583213880
Category : Water
Languages : en
Pages : 256
Book Description
CD-ROM contains chapter 4 and appendices A & B.
Evaluation of the Microbiology Standards for Drinking Water
Author: Charles W. Hendricks
Publisher:
ISBN:
Category : Drinking water
Languages : en
Pages : 252
Book Description
Publisher:
ISBN:
Category : Drinking water
Languages : en
Pages : 252
Book Description
Impact of UV Disinfection on Biological Stability
Author: G. Gagnon
Publisher: International Water Assn
ISBN: 9781843398943
Category : Science
Languages : en
Pages : 136
Book Description
The overall objective of the research was to evalu
Publisher: International Water Assn
ISBN: 9781843398943
Category : Science
Languages : en
Pages : 136
Book Description
The overall objective of the research was to evalu
Microbial Source Tracking
Author: Jorge W. Santo Domingo
Publisher: Emerging Issues in Food Safety
ISBN: 9781555813741
Category : Medical
Languages : en
Pages : 285
Book Description
Presents a state-of-the-art review of the current technology and applications being utilized to identify sources of fecal contamination in waterways. - Serves as a useful reference for researchers in the food industry, especially scientists investigating etiological agents responsible for food contamination. - Provides background information on MST methods and the assumptions and limitations associated with their use. - Covers a broad range of topics related to MST, including environmental monitoring, public health and national security, population biology, and microbial ecology. - Offers valuable insights into future research directions and technology developments.
Publisher: Emerging Issues in Food Safety
ISBN: 9781555813741
Category : Medical
Languages : en
Pages : 285
Book Description
Presents a state-of-the-art review of the current technology and applications being utilized to identify sources of fecal contamination in waterways. - Serves as a useful reference for researchers in the food industry, especially scientists investigating etiological agents responsible for food contamination. - Provides background information on MST methods and the assumptions and limitations associated with their use. - Covers a broad range of topics related to MST, including environmental monitoring, public health and national security, population biology, and microbial ecology. - Offers valuable insights into future research directions and technology developments.