scholarly journals Waterborne outbreaks reported in the United States

2006 ◽  
Vol 4 (S2) ◽  
pp. 19-30 ◽  
Author(s):  
Michael F. Craun ◽  
Gunther F. Craun ◽  
Rebecca L. Calderon ◽  
Michael J. Beach
Keyword(s):  
United States ◽  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water System ◽  
Recent Decade ◽  
The United States ◽  
Water Disinfection ◽  
True Incidence ◽  
Additional Information

Epidemic waterborne risks are discussed in this paper. Although the true incidence of waterborne illness is not reflected in the currently reported outbreak statistics, outbreak surveillance has provided information about the important waterborne pathogens, relative degrees of risk associated with water sources and treatment processes, and adequacy of regulations. Pathogens and water system deficiencies that are identified in outbreaks may also be important causes of endemic waterborne illness. In recent years, investigators have identified a large number of pathogens responsible for outbreaks, and research has focused on their sources, resistance to water disinfection, and removal from drinking water. Outbreaks in surface water systems have decreased in the recent decade, most likely due to recent regulations and improved treatment efficacy. Of increased importance, however, are outbreaks caused by the microbial contamination of water distribution systems. In order to better estimate waterborne risks in the United States, additional information is needed about the contribution of distribution system contaminants to endemic waterborne risks and undetected waterborne outbreaks, especially those associated with distribution system contaminants.

scholarly journals Causes of Outbreaks Associated with Drinking Water in the United States from 1971 to 2006

2010 ◽  
Vol 23 (3) ◽  
pp. 507-528 ◽  
Author(s):  
Gunther F. Craun ◽  
Joan M. Brunkard ◽  
Jonathan S. Yoder ◽  
Virginia A. Roberts ◽  
Joe Carpenter ◽  
...  
Keyword(s):  
Public Health ◽  
United States ◽  
Distribution System ◽  
Water System ◽  
The United States ◽  
Water Systems ◽  
Outbreak Detection ◽  
Waterborne Disease ◽  
Public Water Systems ◽  
Annual Proportion

SUMMARY Since 1971, the CDC, EPA, and Council of State and Territorial Epidemiologists (CSTE) have maintained the collaborative national Waterborne Disease and Outbreak Surveillance System (WBDOSS) to document waterborne disease outbreaks (WBDOs) reported by local, state, and territorial health departments. WBDOs were recently reclassified to better characterize water system deficiencies and risk factors; data were analyzed for trends in outbreak occurrence, etiologies, and deficiencies during 1971 to 2006. A total of 833 WBDOs, 577,991 cases of illness, and 106 deaths were reported during 1971 to 2006. Trends of public health significance include (i) a decrease in the number of reported outbreaks over time and in the annual proportion of outbreaks reported in public water systems, (ii) an increase in the annual proportion of outbreaks reported in individual water systems and in the proportion of outbreaks associated with premise plumbing deficiencies in public water systems, (iii) no change in the annual proportion of outbreaks associated with distribution system deficiencies or the use of untreated and improperly treated groundwater in public water systems, and (iv) the increasing importance of Legionella since its inclusion in WBDOSS in 2001. Data from WBDOSS have helped inform public health and regulatory responses. Additional resources for waterborne disease surveillance and outbreak detection are essential to improve our ability to monitor, detect, and prevent waterborne disease in the United States.

Memphis Light, Gas and Water Division Experience With Aging of Electric, Gas, and Water Systems

1993 ◽  
Vol 46 (5) ◽  
pp. 183-186
Author(s):  
Charles Pickel
Keyword(s):  
United States ◽  
Customer Satisfaction ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Distribution Systems ◽  
The United States ◽  
Water Systems ◽  
Recent Survey ◽  
Effective Manner ◽  
Long Life

Electric, gas and water distribution systems can have an extremely long life when properly designed, installed and maintained. MLGW is proof positive that aging distribution systems can be managed in an effective manner. Customer satisfaction is a high priority with Division management. According to a recent survey, Memphians enjoy the lowest average monthly utility bills among the 25 largest cities in the United States.

scholarly journals Array of prediction tools for understanding extent of wall effects on DBP formation in drinking water distribution systems

2019 ◽  
Vol 68 (6) ◽  
pp. 390-398 ◽  
Author(s):  
Sandhya Rao Poleneni ◽  
Enos C. Inniss
Keyword(s):  
Ductile Iron ◽  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Water Movement ◽  
The United States ◽  
Wall Effects ◽  
System Effect ◽  
Drinking Water Distribution Systems ◽  
Simulated Distribution

Abstract The Stage 2 Disinfectant and Disinfection By-Product (D/DBP) regulations of the United States force water utilities to be more concerned with their distributed water quality. Improved compliance requires understanding of reaction kinetics and wall effects of different distribution materials used on DBP formation. To validate results in a full-scale system, effect of different materials, wall effects, bulk reactions, and water movement is analyzed using simulated distribution system (SDS) tests, material specific simulated distribution system (MS-SDS) tests, pipe loop, and pipe section reactor (PSR); all built using materials from the city of Columbia, Missouri's distribution system. On average, the choice of polyvinyl chloride (PVC) and ductile iron can account for as much as 36% difference in trihalomethane (TTHM) formation and 60% difference in chlorine residual decay over time irrespective of the prediction model and operational strategy used. In the case of ductile iron, pipe effect (PE) is <1, which shows that in the ductile iron pipe systems there is a net loss of TTHM yield due to non-TTHM forming chlorine demand imposed by the pipe environment, whereas in PVC pipe, PE is >1. In PVC systems there is an overall increase in TTHM formation as a result of pipe wall surface reactions.

scholarly journals Persistence of Nontuberculous Mycobacteria in a Drinking Water System after Addition of Filtration Treatment

2006 ◽  
Vol 72 (9) ◽  
pp. 5864-5869 ◽  
Author(s):  
Elizabeth D. Hilborn ◽  
Terry C. Covert ◽  
Mitchell A. Yakrus ◽  
Stephanie I. Harris ◽  
Sandra F. Donnelly ◽  
...  
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Cold Water ◽  
Nontuberculous Mycobacteria ◽  
Treatment Plant ◽  
Water System ◽  
Drinking Water Treatment ◽  
Drinking Water System

ABSTRACT There is evidence that drinking water may be a source of infections with pathogenic nontuberculous mycobacteria (NTM) in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular colonization of protozoa. Our goal was to determine whether we could detect a reduction in the prevalence of NTM recovered from an unfiltered surface drinking water system after the addition of ozonation and filtration treatment and to characterize NTM isolates by using molecular methods. We sampled water from two initially unfiltered surface drinking water treatment plants over a 29-month period. One plant received the addition of filtration and ozonation after 6 months of sampling. Sample sites included those at treatment plant effluents, distributed water, and cold water taps (point-of-use [POU] sites) in public or commercial buildings located within each distribution system. NTM were recovered from 27% of the sites. POU sites yielded the majority of NTM, with >50% recovery despite the addition of ozonation and filtration. Closely related electrophoretic groups of Mycobacterium avium were found to persist at POU sites for up to 26 months. Water collected from POU cold water outlets was persistently colonized with NTM despite the addition of ozonation and filtration to a drinking water system. This suggests that cold water POU outlets need to be considered as a potential source of chronic human exposure to NTM.

Rainwater Harvesting as a Distributed Resource

2010 ◽  
Author(s):  
John H. Whear
Keyword(s):  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Large Scale ◽  
Rainwater Harvesting ◽  
San Antonio ◽  
Water System ◽  
System Quality ◽  
Recycled Water

Explore the possibilities, difficulties, and benefits of large scale rainwater harvesting using recycled water distribution systems. This paper explores the growing use of recycled water and the possibilities that distribution systems have created. It investigates water quality of rainwater harvesting (RWH) systems and the quality of recycled water and their uses. It examines the amount of rain water available using aproximatly 10% of available roof area in the city and examines the benefits of large scale rainwater harvesting unique to San Antonio. An exhaustive search of published materials was conducted, coupled with communications with the Texas Water Development Board and the San Antonio Water System. Quality standards for recycled water were compared with known test results for harvested rainwater. With the use of mathematical models, a distributed rainwater harvesting systems was compared to a stand alone system. Connection to a distribution system reduces the cost of rainwater harvesting by eliminating the need for large amounts of storage, which can account for 50% of the total costs of a standalone system. With minor filtering and periodic quality checks, large structures may supply sufficient amounts of rainwater to justify being a source of water in a recycled water distribution system.

scholarly journals Optimising the Number of Pumps and Balancing Valves in Chilled Water Distribution Systems

2019 ◽  
Vol 111 ◽  
pp. 01071
Author(s):  
Adrian Retezan ◽  
Szilveszter Geyer Ehrenberg
Keyword(s):  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Cooling System ◽  
Water System ◽  
Good Control ◽  
Electrical Energy ◽  
Comfort Level ◽  
Common System ◽  
Chilled Water

Everyday life does involve use of cooling systems for different areas and scenarios. We use them to keep our thermal comfort level at optimum, either to get rid of some extra heat from technological systems. From various cooling solutions, one and very common system is the chilled water system, where centralised chiller plants produce the cooling energy and all terminal units do receive cooling energy using a distribution loop. According to statistical data, electrical energy consumption of pumps might be up to 17% of entire electrical use of the cooling plant. When designing our cooling system loads during operation will not be same all the time. Variation must be treated accordingly, therefore to get best efficiency of the system, we must get a good control. Beside shut-off motorised valves our balancing must be considered in different scenarios. The paper looks to summarize the challenges in getting a good balancing and energy efficiency in chilled water distribution system.

scholarly journals Development of pipe deterioration models for water distribution systems using EPR

2008 ◽  
Vol 10 (2) ◽  
pp. 113-126 ◽  
Author(s):  
L. Berardi ◽  
O. Giustolisi ◽  
Z. Kapelan ◽  
D. A. Savic
Keyword(s):  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Network Performance ◽  
Polynomial Regression ◽  
Water System ◽  
Evolutionary Polynomial Regression ◽  
Management Context ◽  
Expected Benefits ◽  
Utility Managers

The economic and social costs of pipe failures in water and wastewater systems are increasing, putting pressure on utility managers to develop annual replacement plans for critical pipes that balance investment with expected benefits in a risk-based management context. In addition to the need for a strategy for solving such a multi-objective problem, analysts and water system managers need reliable and robust failure models for assessing network performance. In particular, they are interested in assessing a conduit's propensity to fail and how to assign criticality to an individual pipe segment. In this paper, pipe deterioration is modelled using Evolutionary Polynomial Regression. This data-driven technique yields symbolic formulae that are intuitive and easily understandable by practitioners. The case study involves a water quality zone within a distribution system and entails the collection of historical data to develop network performance indicators. Finally, an approach for incorporating such indicators into a decision support system for pipe rehabilitation/replacement planning is introduced and articulated.

scholarly journals Giardiasis outbreaks in the United States, 1971–2011

2016 ◽  
Vol 144 (13) ◽  
pp. 2790-2801 ◽  
Author(s):  
E. A. ADAM ◽  
J. S. YODER ◽  
L. H. GOULD ◽  
M. C. HLAVSA ◽  
J. W. GARGANO
Keyword(s):  
United States ◽  
Drinking Water ◽  
Water Treatment ◽  
Distribution System ◽  
Distribution Systems ◽  
The United States ◽  
Lessons Learned ◽  
Food Handler ◽  
Recreational Water ◽  
Prevention Measures

SUMMARYGiardia intestinalis is the leading parasitic aetiology of human enteric infections in the United States, with an estimated 1·2 million cases occurring annually. To better understand transmission, we analysed data on all giardiasis outbreaks reported to the Centers for Disease Control and Prevention for 1971–2011. The 242 outbreaks, affecting ~41 000 persons, resulted from waterborne (74·8%), foodborne (15·7%), person-to-person (2·5%), and animal contact (1·2%) transmission. Most (74·6%) waterborne outbreaks were associated with drinking water, followed by recreational water (18·2%). Problems with water treatment, untreated groundwater, and distribution systems were identified most often during drinking water-associated outbreak investigations; problems with water treatment declined after the 1980s. Most recreational water-associated outbreaks were linked to treated swimming venues, with pools and wading pools implicated most often. Produce was implicated most often in foodborne outbreaks. Additionally, foods were most commonly prepared in a restaurant and contaminated by a food handler. Lessons learned from examining patterns in outbreaks over time can help prevent future disease. Groundwater and distribution system vulnerabilities, inadequate pool disinfection, fruit and vegetable contamination, and poor food handler hygiene are promising targets for giardiasis prevention measures.

Understanding Risks: Natural Gas Distribution Piping in the United States

2020 ◽  
Author(s):  
Sara Lyons ◽  
Mohammad Modarres
Keyword(s):  
United States ◽  
Natural Gas ◽  
Distribution System ◽  
Distribution Systems ◽  
The United States ◽  
Pipeline System ◽  
Gas Distribution ◽  
The Public ◽  
Accident Data ◽  
The U.S

Abstract Two hundred sixty-nine regulated pipeline system accidents caused fatalities and/or injuries in the United States between 2010 and 2018, resulting in 106 fatalities and 599 injuries requiring hospitalization. About 84% of these serious accidents occurred on gas distribution systems, which primarily transport natural gas. This study adapts probabilistic risk assessment (PRA) methods which are used predominantly in the space and nuclear industries to gas distribution systems in the U.S. Nationwide system and accident data are used to evaluate natural gas distribution system risks, estimate how many additional resources the public would be willing to dedicate to reduce or eliminate these risks, and determine which improvement areas warrant further evaluation. Recommendations regarding the overall PRA-based framework, as well as the scope, quality, and level of detail of the underlying data, are provided.

Sign in / Sign up

Export Citation Format

Share Document