Understanding and Controlling iron Release in Distribution Systems

EPA Science Inventory

Generation of red-water resulting from the release of iron from drinking water distribution system materials is a major consumer complaint of drinking water systems. The objective of this presentation is to provide a fundamental basis for iron release from drinking water distrib...

Draft Genome Sequence of Two Sphingopyxis sp. Strains, Dominant Members of the Bacterial Community Associated with a Drinking Water Distribution System Simulator

EPA Science Inventory

We report the draft genome of two Sphingopyxis spp. strains isolated from a chloraminated drinking water distribution system simulator. Both strains are ubiquitous residents and early colonizers of water distribution systems. Genomic annotation identified a class 1 integron (in...

Evaluation of biological stability and corrosion potential in drinking water distribution systems: a case study.

PubMed

Chien, C C; Kao, C M; Chen, C W; Dong, C D; Chien, H Y

2009-06-01

The appearance of assimilable organic carbon (AOC), microbial regrowth, disinfection by-products (DBPs), and pipe corrosion in drinking water distribution systems are among those major safe drinking water issues in many countries. The water distribution system of Cheng-Ching Lake Water Treatment Plant (CCLWTP) was selected in this study to evaluate the: (1) fate and transport of AOC, DBPs [e.g., trihalomethanes (THMs), haloacetic acids (HAAs)], and other organic carbon indicators in the selected distribution system, (2) correlations between AOC (or DBPs) and major water quality parameters [e.g. dissolved oxygen (DO), free residual chlorine, and bacteria, and (3) causes and significance of corrosion problems of the water pipes in this system. In this study, seasonal water samples were collected from 13 representative locations in the distribution system for analyses of AOC, DBPs, and other water quality indicators. Results indicate that residual free chlorine concentrations in the distribution system met the drinking water standards (0.2 to 1 mg l(-1)) established by Taiwan Environmental Protection Administration (TEPA). Results show that AOC measurements correlated positively with total organic carbon (TOC) and UV-254 (an organic indicator) values in this system. Moreover, AOC concentrations at some locations were higher than the 50 microg acetate-C l(-1) standard established by Taiwan Water Company. This indicates that the microbial regrowth might be a potential water quality problem in this system. Higher DO measurements (>5.7 mg l(-1)) might cause the aerobic biodegradation of THMs and HAAs in the system, and thus, low THMs (<0.035 mg l(-1)) and HAAs (<0.019 mg l(-1)) concentrations were observed at all sampling locations. Results from the observed negative Langelier Saturation Index (LSI) values, higher Ryznar Stability Index (RSI) values, and high Fe3+ concentrations at some pipe-end locations indicate that highly oxidative and corrosive conditions occurred. This reveals that pipe replacement should be considered at these locations. These findings would be helpful in managing the water distribution system for maintaining a safe drinking water quality.

Passive containment cooling water distribution device

DOEpatents

Conway, Lawrence E.; Fanto, Susan V.

1994-01-01

A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using a series of radial guide elements and cascading weir boxes to collect and then distribute the cooling water into a series of distribution areas through a plurality of cascading weirs. The cooling water is then uniformly distributed over the curved surface by a plurality of weir notches in the face plate of the weir box.

Performance Monitoring of Residential Hot Water Distribution Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liao, Anna; Lanzisera, Steven; Lutz, Jim

Current water distribution systems are designed such that users need to run the water for some time to achieve the desired temperature, wasting energy and water in the process. We developed a wireless sensor network for large-scale, long time-series monitoring of residential water end use. Our system consists of flow meters connected to wireless motes transmitting data to a central manager mote, which in turn posts data to our server via the internet. This project also demonstrates a reliable and flexible data collection system that could be configured for various other forms of end use metering in buildings. The purposemore » of this study was to determine water and energy use and waste in hot water distribution systems in California residences. We installed meters at every end use point and the water heater in 20 homes and collected 1s flow and temperature data over an 8 month period. For a typical shower and dishwasher events, approximately half the energy is wasted. This relatively low efficiency highlights the importance of further examining the energy and water waste in hot water distribution systems.« less

Examination and characterization of distribution system biofilms.

PubMed Central

LeChevallier, M W; Babcock, T M; Lee, R G

1987-01-01

Investigations concerning the role of distribution system biofilms on water quality were conducted at a drinking water utility in New Jersey. The utility experienced long-term bacteriological problems in the distribution system, while treatment plant effluents were uniformly negative for coliform bacteria. Results of a monitoring program showed increased coliform levels as the water moved from the treatment plant through the distribution system. Increased coliform densities could not be accounted for by growth of the cells in the water column alone. Identification of coliform bacteria showed that species diversity increased as water flowed through the study area. All materials in the distribution system had high densities of heterotrophic plate count bacteria, while high levels of coliforms were detected only in iron tubercles. Coliform bacteria with the same biochemical profile were found both in distribution system biofilms and in the water column. Assimilable organic carbon determinations showed that carbon levels declined as water flowed through the study area. Maintenance of a 1.0-mg/liter free chlorine residual was insufficient to control coliform occurrences. Flushing and pigging the study area was not an effective control for coliform occurrences in that section. Because coliform bacteria growing in distribution system biofilms may mask the presence of indicator organisms resulting from a true breakdown of treatment barriers, the report recommends that efforts continue to find methods to control growth of coliform bacteria in pipeline biofilms. Images PMID:3435140

Developing Fluorescence Sensor Systems for Early Detection of Nitrification Events in Chloraminated Drinking Water Distribution Systems

EPA Science Inventory

Detection of nitrification events in chloraminated drinking water distribution systems remains an ongoing challenge for many drinking water utilities, including Dallas Water Utilities (DWU) and the City of Houston (CoH). Each year, these utilities experience nitrification events ...

Nitrification in Chloraminated Drinking Water Distribution Systems - Occurrence

EPA Science Inventory

This chapter discusses available information on nitrification occurrence in drinking water chloraminated distribution systems. Chapter 4 provides an introduction to causes and controls for nitrification in chloraminated drinking water systems. Both chapters are intended to serve ...

Water Distribution System Deficiencies and Gastrointestinal Illness: A Systematic Review and Meta-Analysis

PubMed Central

Gruber, Joshua S.; Colford, John M.

2014-01-01

Background: Water distribution systems are vulnerable to performance deficiencies that can cause (re)contamination of treated water and plausibly lead to increased risk of gastrointestinal illness (GII) in consumers. Objectives: It is well established that large system disruptions in piped water networks can cause GII outbreaks. We hypothesized that routine network problems can also contribute to background levels of waterborne illness and conducted a systematic review and meta-analysis to assess the impact of distribution system deficiencies on endemic GII. Methods: We reviewed published studies that compared direct tap water consumption to consumption of tap water re-treated at the point of use (POU) and studies of specific system deficiencies such as breach of physical or hydraulic pipe integrity and lack of disinfectant residual. Results: In settings with network malfunction, consumers of tap water versus POU-treated water had increased GII [incidence density ratio (IDR) = 1.34; 95% CI: 1.00, 1.79]. The subset of nonblinded studies showed a significant association between GII and tap water versus POU-treated water consumption (IDR = 1.52; 95% CI: 1.05, 2.20), but there was no association based on studies that blinded participants to their POU water treatment status (IDR = 0.98; 95% CI: 0.90, 1.08). Among studies focusing on specific network deficiencies, GII was associated with temporary water outages (relative risk = 3.26; 95% CI: 1.48, 7.19) as well as chronic outages in intermittently operated distribution systems (odds ratio = 1.61; 95% CI: 1.26, 2.07). Conclusions: Tap water consumption is associated with GII in malfunctioning distribution networks. System deficiencies such as water outages also are associated with increased GII, suggesting a potential health risk for consumers served by piped water networks. Citation: Ercumen A, Gruber JS, Colford JM Jr. 2014. Water distribution system deficiencies and gastrointestinal illness: a systematic review and meta-analysis. Environ Health Perspect 122:651–660; http://dx.doi.org/10.1289/ehp.1306912 PMID:24659576

Water System Resiliency: Lessons from Boston's 2010 Water Emergency

NASA Astrophysics Data System (ADS)

Phillips, N.; Boston Urban Metabolism Ultra-Ex Team

2010-12-01

On May 1, 2010, a ten foot diameter water pipe, the sole pipe supplying potable water to 2.2 million residents of Greater Boston, burst. Categorized as a "catastrophic" leak by the Massachusetts Water Resources Authority, Governor Deval Patrick declared a State of Emergency, mobilizing local, state and federal disaster responses. By May 4, 2010, a boil-water order was lifted after the leak was fixed. This event has provided many lessons about the resiliency of municipal water system infrastructure, the level of human understanding of reliability and vulnerability of resource distribution systems, and the human capacity to adapt in short and longer terms to disturbances in resource distribution systems, and to learn. This talk will use a narrative of the events during May 2010 in Boston to explore the broader question of the nature of resilient resource distribution networks, and describe a heuristic, semi-quantitative model for resilient urban resource distribution networks, including water.

IRON TUBERCULATION: PHYSIO-CHEMICAL CHARACTERIZATION OF A SINGLE PIPE FROM A DRINKING WATER DISTRIBUTION SYSTEM

EPA Science Inventory

The nature of iron tubercles inside unlined iron pipes of drinking water distribution systems are influenced by water quality and therefore susceptible to changes in water chemistry. The underlying assumption is that tubercles in a system have similar physio-chemical properties. ...

Drinking water for dairy cattle: always a benefit or a microbiological risk?

PubMed

Van Eenige, M J E M; Counotte, G H M; Noordhuizen, J P T M

2013-02-01

Drinking water can be considered an essential nutrient for dairy cattle. However, because it comes from different sources, its chemical and microbiological quality does not always reach accepted standards. Moreover, water quality is not routinely assessed on dairy farms. The microecology of drinking water sources and distribution systems is rather complex and still not fully understood. Water quality is adversely affected by the formation of biofilms in distribution systems, which form a persistent reservoir for potentially pathogenic bacteria. Saprophytic microorganisms associated with such biofilms interact with organic and inorganic matter in water, with pathogens, and even with each other. In addition, the presence of biofilms in water distribution systems makes cleaning and disinfection difficult and sometimes impossible. This article describes the complex dynamics of microorganisms in water distribution systems. Water quality is diminished primarily as a result of faecal contamination and rarely as a result of putrefaction in water distribution systems. The design of such systems (with/ without anti-backflow valves and pressure) and the materials used (polyethylene enhances biofilm; stainless steel does not) affect the quality of water they provide. The best option is an open, funnel-shaped galvanized drinking trough, possibly with a pressure system, air inlet, and anti-backflow valves. A poor microbiological quality of drinking water may adversely affect feed intake, and herd health and productivity. In turn, public health may be affected because cattle can become a reservoir of microorganisms hazardous to humans, such as some strains of E. coli, Yersinia enterocolitica, and Campylobacter jejuni. A better understanding of the biological processes in water sources and distribution systems and of the viability of microorganisms in these systems may contribute to better advice on herd health and productivity at a farm level. Certain on-farm risk factors for water quality have been identified. A practical approach will facilitate the control and management of these risks, and thereby improve herd health and productivity.

Longitudinal and Source-to-Tap New Orleans, LA, U.S.A. Drinking Water Microbiology.

PubMed

Hull, Natalie M; Holinger, Eric P; Ross, Kimberly A; Robertson, Charles E; Harris, J Kirk; Stevens, Mark J; Pace, Norman R

2017-04-18

The two municipal drinking water systems of New Orleans, LA, U.S.A. were sampled to compare the microbiology of independent systems that treat the same surface water from the Mississippi River. To better understand temporal trends and sources of microbiology delivered to taps, these treatment plants and distribution systems were subjected to source-to-tap sampling over four years. Both plants employ traditional treatment by chloramination, applied during or after settling, followed by filtration before distribution in a warm, low water age system. Longitudinal samples indicated microbiology to have stability both spatially and temporally, and between treatment plants and distribution systems. Disinfection had the greatest impact on microbial composition, which was further refined by filtration and influenced by distribution and premise plumbing. Actinobacteria spp. exhibited trends with treatment. In particular, Mycobacterium spp., very low in finished waters, occurred idiosyncratically at high levels in some tap waters, indicating distribution and/or premise plumbing as main contributors of mycobacteria. Legionella spp., another genus containing potential opportunistic pathogens, also occurred ubiquitously. Source water microbiology was most divergent from tap water, and each step of treatment brought samples more closely similar to tap waters.

Earthquake hazards to domestic water distribution systems in Salt Lake County, Utah

USGS Publications Warehouse

Highland, Lynn M.

1985-01-01

A magnitude-7. 5 earthquake occurring along the central portion of the Wasatch Fault, Utah, may cause significant damage to Salt Lake County's domestic water system. This system is composed of water treatment plants, aqueducts, distribution mains, and other facilities that are vulnerable to ground shaking, liquefaction, fault movement, and slope failures. Recent investigations into surface faulting, landslide potential, and earthquake intensity provide basic data for evaluating the potential earthquake hazards to water-distribution systems in the event of a large earthquake. Water supply system components may be vulnerable to one or more earthquake-related effects, depending on site geology and topography. Case studies of water-system damage by recent large earthquakes in Utah and in other regions of the United States offer valuable insights in evaluating water system vulnerability to earthquakes.

MEASURING AND MODELING VARIATIONS IN DISTRIBUTION SYSTEM WATER QUALITY

EPA Science Inventory

The authors describe a field study that examined the effects of hydraulic mixing on water quality variations in a distribution system. Conducted at the North Penn Water Authority (average production of 5 mgd and 225 mi of distribution pipe), the study incorporated a field samplin...

A Visual Insight into the Degradation of Metals Used in Drinking Water Distribution Systems Using AFM

EPA Science Inventory

Evaluating the fundamental corrosion and passivation of metallic copper used in drinking water distribution materials is important in understanding the overall mechanism of the corrosion process. Copper pipes are widely used for drinking water distribution systems and although it...

PHYLOGENETIC ANALYSIS OF PROKARYOTIC AND EUKARYOTIC MICROORGANISMS IN A DRINKING WATER PIPE LOOP SYSTEM

EPA Science Inventory

Within potable water distribution systems, opportunistic pathogens such as Legionella species infect protozoa, gaining protection from disinfectant residuals. Analyzing the prokaryotic and eukaryotic populations in distribution system water provides a basis for understanding the...

PHYLOGENETIC ANALYSIS OF PROKARYOTIC AND EUKAROYOTIC MICROOORGANISMS IN A DRINKING WATER PIPE LOOP SYSTEM

EPA Science Inventory

Within potable water distribution systems, opportunistic pathogens such as Legionella species infect protozoa, gaining protection from disinfectant residuals. Analyzing the prokaryotic and eukaryotic populations in distribution system water provides a basis for understanding the...

Bacterial Composition in a Metropolitan Drinking Water Distribution System Utilizing Different Source Waters

EPA Science Inventory

The microbial community structure was investigated from bulk phase water samples of multiple collection sites from two service areas within the Cincinnati drinking water distribution system (DWDS). Each area is associated with a different primary source of water (i.e., groundwat...

Significance of losses in water distribution systems in India

PubMed Central

Raman, V.

1983-01-01

Effective management of water supply systems consists in supplying adequate quantities of clean water to the population. Detailed pilot studies of water distribution systems were carried out in 9 cities in India during 1971-81 to establish the feasibility of a programme of assessment, detection, and control of water losses from supply systems. A cost-benefit analysis was carried out. Water losses from mains and service pipes in the areas studied amounted to 20-35% of the total flow in the system. At a conservative estimate, the national loss of processed water through leaks in the water distribution systems amounts to 1012 litres per year, which is equivalent to 500 million rupees. It is possible to bring down the water losses in the pipe mains to 3-5% of the total flow, and the cost incurred on the control programme can be recovered in 6-18 months. Appropriate conservation measures will help in achieving the goals of the International Water Supply and Sanitation Decade to provide clean water for all. PMID:6418401

Significance of losses in water distribution systems in India.

PubMed

Raman, V

1983-01-01

Effective management of water supply systems consists in supplying adequate quantities of clean water to the population. Detailed pilot studies of water distribution systems were carried out in 9 cities in India during 1971-81 to establish the feasibility of a programme of assessment, detection, and control of water losses from supply systems. A cost-benefit analysis was carried out. Water losses from mains and service pipes in the areas studied amounted to 20-35% of the total flow in the system. At a conservative estimate, the national loss of processed water through leaks in the water distribution systems amounts to 10(12) litres per year, which is equivalent to 500 million rupees.It is possible to bring down the water losses in the pipe mains to 3-5% of the total flow, and the cost incurred on the control programme can be recovered in 6-18 months. Appropriate conservation measures will help in achieving the goals of the International Water Supply and Sanitation Decade to provide clean water for all.

WATER DISTRIBUTION SYSTEM ANALYSIS: FIELD STUDIES, MODELING AND MANAGEMENT

EPA Science Inventory

The user‘s guide entitled “Water Distribution System Analysis: Field Studies, Modeling and Management” is a reference guide for water utilities and an extensive summarization of information designed to provide drinking water utility personnel (and related consultants and research...

Temperature diagnostic to identify high risk areas and optimize Legionella pneumophila surveillance in hot water distribution systems.

PubMed

Bédard, Emilie; Fey, Stéphanie; Charron, Dominique; Lalancette, Cindy; Cantin, Philippe; Dolcé, Patrick; Laferrière, Céline; Déziel, Eric; Prévost, Michèle

2015-03-15

Legionella pneumophila is frequently detected in hot water distribution systems and thermal control is a common measure implemented by health care facilities. A risk assessment based on water temperature profiling and temperature distribution within the network is proposed, to guide effective monitoring strategies and allow the identification of high risk areas. Temperature and heat loss at control points (water heater, recirculation, representative points-of-use) were monitored in various sections of five health care facilities hot water distribution systems and results used to develop a temperature-based risk assessment tool. Detailed investigations show that defective return valves in faucets can cause widespread temperature losses because of hot and cold water mixing. Systems in which water temperature coming out of the water heaters was kept consistently above 60 °C and maintained above 55 °C across the network were negative for Legionella by culture or qPCR. For systems not meeting these temperature criteria, risk areas for L. pneumophila were identified using temperature profiling and system's characterization; higher risk was confirmed by more frequent microbiological detection by culture and qPCR. Results confirmed that maintaining sufficiently high temperatures within hot water distribution systems suppressed L. pneumophila culturability. However, the risk remains as shown by the persistence of L. pneumophila by qPCR. Copyright © 2015 Elsevier Ltd. All rights reserved.

GEOCHEMISTRY OF SULFUR IN IRON CORROSION SCALES FOUND IN DRINKING WATER DISTRIBUTION SYSTEMS

EPA Science Inventory

Iron-sulfur geochemistry is important in many natural and engineered environments, including drinking water systems. In the anaerobic environment beneath scales of corroding iron drinking water distribution system pipes, sulfate reducing bacteria (SRB) produce sulfide from natu...

Evaluating online data of water quality changes in a pilot drinking water distribution system with multivariate data exploration methods.

PubMed

Mustonen, Satu M; Tissari, Soile; Huikko, Laura; Kolehmainen, Mikko; Lehtola, Markku J; Hirvonen, Arja

2008-05-01

The distribution of drinking water generates soft deposits and biofilms in the pipelines of distribution systems. Disturbances in water distribution can detach these deposits and biofilms and thus deteriorate the water quality. We studied the effects of simulated pressure shocks on the water quality with online analysers. The study was conducted with copper and composite plastic pipelines in a pilot distribution system. The online data gathered during the study was evaluated with Self-Organising Map (SOM) and Sammon's mapping, which are useful methods in exploring large amounts of multivariate data. The objective was to test the usefulness of these methods in pinpointing the abnormal water quality changes in the online data. The pressure shocks increased temporarily the number of particles, turbidity and electrical conductivity. SOM and Sammon's mapping were able to separate these situations from the normal data and thus make those visible. Therefore these methods make it possible to detect abrupt changes in water quality and thus to react rapidly to any disturbances in the system. These methods are useful in developing alert systems and predictive applications connected to online monitoring.

Ontology for Life-Cycle Modeling of Water Distribution Systems: Application of Model View Definition Attributes

DTIC Science & Technology

2013-06-01

ER D C/ CE RL C R- 13 -5 Ontology for Life-Cycle Modeling of Water Distribution Systems : Application of Model View Definition...2013 Ontology for Life-Cycle Modeling of Water Distribution Systems : Application of Model View Definition Attributes Kristine K. Fallon, Robert A...interior plumbing systems and the information exchange requirements for every participant in the design. The findings were used to develop an

Injection of Contaminants into a Simulated Water Distribution System Equipped with Continuous Multi-Parameter Water Monitors

EPA Science Inventory

The U.S. EPA’s Technology Testing and Evaluation Program has been charged by EPA to evaluate the performance of commercially available water security-related technologies. Multi-parameter water monitors for distributions systems have been evaluated as such a water security techn...

Optimization of European call options considering physical delivery network and reservoir operation rules

NASA Astrophysics Data System (ADS)

Cheng, Wei-Chen; Hsu, Nien-Sheng; Cheng, Wen-Ming; Yeh, William W.-G.

2011-10-01

This paper develops alternative strategies for European call options for water purchase under hydrological uncertainties that can be used by water resources managers for decision making. Each alternative strategy maximizes its own objective over a selected sequence of future hydrology that is characterized by exceedance probability. Water trade provides flexibility and enhances water distribution system reliability. However, water trade between two parties in a regional water distribution system involves many issues, such as delivery network, reservoir operation rules, storage space, demand, water availability, uncertainty, and any existing contracts. An option is a security giving the right to buy or sell an asset; in our case, the asset is water. We extend a flow path-based water distribution model to include reservoir operation rules. The model simultaneously considers both the physical distribution network as well as the relationships between water sellers and buyers. We first test the model extension. Then we apply the proposed optimization model for European call options to the Tainan water distribution system in southern Taiwan. The formulation lends itself to a mixed integer linear programming model. We use the weighing method to formulate a composite function for a multiobjective problem. The proposed methodology provides water resources managers with an overall picture of water trade strategies and the consequence of each strategy. The results from the case study indicate that the strategy associated with a streamflow exceedence probability of 50% or smaller should be adopted as the reference strategy for the Tainan water distribution system.

Potential Chemical Effects of Changes in the Source of Water Supply for the Albuquerque Bernalillo County Water Utility Authority

USGS Publications Warehouse

Bexfield, Laura M.; Anderholm, Scott K.

2008-01-01

Chemical modeling was used by the U.S. Geological Survey, in cooperation with the Albuquerque Bernalillo County Water Utility Authority (henceforth, Authority), to gain insight into the potential chemical effects that could occur in the Authority's water distribution system as a result of changing the source of water used for municipal and industrial supply from ground water to surface water, or to some mixture of the two sources. From historical data, representative samples of ground-water and surface-water chemistry were selected for modeling under a range of environmental conditions anticipated to be present in the distribution system. Mineral phases calculated to have the potential to precipitate from ground water were compared with the compositions of precipitate samples collected from the current water distribution system and with mineral phases calculated to have the potential to precipitate from surface water and ground-water/surface-water mixtures. Several minerals that were calculated to have the potential to precipitate from ground water in the current distribution system were identified in precipitate samples from pipes, reservoirs, and water heaters. These minerals were the calcium carbonates aragonite and calcite, and the iron oxides/hydroxides goethite, hematite, and lepidocrocite. Several other minerals that were indicated by modeling to have the potential to precipitate were not found in precipitate samples. For most of these minerals, either the kinetics of formation were known to be unfavorable under conditions present in the distribution system or the minerals typically are not formed through direct precipitation from aqueous solutions. The minerals with potential to precipitate as simulated for surface-water samples and ground-water/surface-water mixtures were quite similar to the minerals with potential to precipitate from ground-water samples. Based on the modeling results along with kinetic considerations, minerals that appear most likely to either dissolve or newly precipitate when surface water or ground-water/surface-water mixtures are delivered through the Authority's current distribution system are carbonates (particularly aragonite and calcite). Other types of minerals having the potential to dissolve or newly precipitate under conditions present throughout most of the distribution system include a form of silica, an aluminum hyroxide (gibbsite or diaspore), or the Fe-containing mineral Fe3(OH)8. Dissolution of most of these minerals (except perhaps the Fe-containing minerals) is not likely to substantially affect trace-element concentrations or aesthetic characteristics of delivered water, except perhaps hardness. Precipitation of these minerals would probably be of concern only if the quantities of material involved were large enough to clog pipes or fixtures. The mineral Fe3(OH)8 was not found in the current distribution system. Some Fe-containing minerals that were identified in the distribution system were associated with relatively high contents of selected elements, including As, Cr, Cu, Mn, Pb, and Zn. However, these Fe-containing minerals were not identified as minerals likely to dissolve when the source of water was changed from ground water to surface water or a ground-water/surface-water mixture. Based on the modeled potential for calcite precipitation and additional calculations of corrosion indices ground water, surface water, and ground-water/surface-water mixtures are not likely to differ greatly in corrosion potential. In particular, surface water and ground-water/surface-water mixtures do not appear likely to dissolve large quantities of existing calcite and expose metal surfaces in the distribution system to substantially increased corrosion. Instead, modeling calculations indicate that somewhat larger masses of material would tend to precipitate from surface water or ground-water/surface-water mixtures compared to ground water alone.

Optimal reconstruction of historical water supply to a distribution system: A. Methodology.

PubMed

Aral, M M; Guan, J; Maslia, M L; Sautner, J B; Gillig, R E; Reyes, J J; Williams, R C

2004-09-01

The New Jersey Department of Health and Senior Services (NJDHSS), with support from the Agency for Toxic Substances and Disease Registry (ATSDR) conducted an epidemiological study of childhood leukaemia and nervous system cancers that occurred in the period 1979 through 1996 in Dover Township, Ocean County, New Jersey. The epidemiological study explored a wide variety of possible risk factors, including environmental exposures. ATSDR and NJDHSS determined that completed human exposure pathways to groundwater contaminants occurred in the past through private and community water supplies (i.e. the water distribution system serving the area). To investigate this exposure, a model of the water distribution system was developed and calibrated through an extensive field investigation. The components of this water distribution system, such as number of pipes, number of tanks, and number of supply wells in the network, changed significantly over a 35-year period (1962--1996), the time frame established for the epidemiological study. Data on the historical management of this system was limited. Thus, it was necessary to investigate alternative ways to reconstruct the operation of the system and test the sensitivity of the system to various alternative operations. Manual reconstruction of the historical water supply to the system in order to provide this sensitivity analysis was time-consuming and labour intensive, given the complexity of the system and the time constraints imposed on the study. To address these issues, the problem was formulated as an optimization problem, where it was assumed that the water distribution system was operated in an optimum manner at all times to satisfy the constraints in the system. The solution to the optimization problem provided the historical water supply strategy in a consistent manner for each month of the study period. The non-uniqueness of the selected historical water supply strategy was addressed by the formulation of a second model, which was based on the first solution. Numerous other sensitivity analyses were also conducted using these two models. Both models are solved using a two-stage progressive optimality algorithm along with genetic algorithms (GAs) and the EPANET2 water distribution network solver. This process reduced the required solution time and generated a historically consistent water supply strategy for the water distribution system.

EFFECT OF VARYING FLOW REGIMES ON BIOFILM DENSITIES IN A DISTRIBUTION SYSTEM SIMULATOR

EPA Science Inventory

Maintenance of a free chlorine residual within water distribution systems is used to reduce the possibility of microbial contamination. However, it has been demonstrated that biofilms within water distribution systems can harbor coliforms. In laboratory scale studies, others have...

The potential for health risks from intrusion of contaminants into the distribution system from pressure transients.

PubMed

LeChevallier, Mark W; Gullick, Richard W; Karim, Mohammad R; Friedman, Melinda; Funk, James E

2003-03-01

The potential for public health risks associated with intrusion of contaminants into water supply distribution systems resulting from transient low or negative pressures is assessed. It is shown that transient pressure events occur in distribution systems; that during these negative pressure events pipeline leaks provide a potential portal for entry of groundwater into treated drinking water; and that faecal indicators and culturable human viruses are present in the soil and water exterior to the distribution system. To date, all observed negative pressure events have been related to power outages or other pump shutdowns. Although there are insufficient data to indicate whether pressure transients are a substantial source of risk to water quality in the distribution system, mitigation techniques can be implemented, principally the maintenance of an effective disinfectant residual throughout the distribution system, leak control, redesign of air relief venting, and more rigorous application of existing engineering standards. Use of high-speed pressure data loggers and surge modelling may have some merit, but more research is needed.

[Research on controlling iron release of desalted water transmitted in existing water distribution system].

PubMed

Tian, Yi-Mei; Liu, Yang; Zhao, Peng; Shan, Jin-Lin; Yang, Suo-Yin; Liu, Wei

2012-04-01

Desalted water, with strong corrosion characteristics, would possibly lead to serious "red water" when transmitted and distributed in existing municipal water distribution network. The main reason for red water phenomenon is iron release in water pipes. In order to study the methods of controlling iron release in existing drinking water distribution pipe, tubercle analysis of steel pipe and cast iron pipe, which have served the distribution system for 30-40 years, was carried out, the main construction materials were Fe3O4 and FeOOH; and immersion experiments were carried in more corrosive pipes. Through changing mixing volume of tap water and desalted water, pH, alkalinity, chloride and sulfate, the influence of different water quality indexes on iron release were mainly analyzed. Meanwhile, based on controlling iron content, water quality conditions were established to meet with the safety distribution of desalted water: volume ratio of potable water and desalted water should be higher than or equal to 2, pH was higher than 7.6, alkalinity was higher than 200 mg x L(-1).

Disinfectant Penetration into Nitrifying Drinking Water Distribution System Biofilm Using Microelectrodes

EPA Science Inventory

Nitrification within drinking water distribution systems reduces water quality, causes difficulties maintaining adequate disinfectant residual, and poses public health concerns including exposure to nitrite, nitrate, and opportunistic pathogenic microorganisms. Monochloramine is...

EVALUATION OF THE ABILITY OF CHLORINE TO INACTIVATE SELECTED ORGANISMS FROM THE BIOFILM OF A DRINKING WATER DISTRIBUTION SYSTEM SIMULATOR FOLLOWING A LONG-TERM WASTEWATER CROSS-CONNECTION

EPA Science Inventory

The drinking water distribution system simulator (DSS) from the U.S. EPA was operated with a direct cross-connection of 0.3% wastewater to system volume per day for 70 d. During the cross-connection, tap water, wastewater, and system discharge water were monitored to ensure that ...

Evaluation of Current Water Treatment and Distribution System Optimization to Provide Safe Drinking Water from Various Source Water Types and Conditions (Deliverable 5.2.C.1)

EPA Science Inventory

Increasingly, drinking water treatment plants (DWTPs) are being challenged by changes in the quality of their source waters and by their aging treatment and distribution system infrastructure. Individually or in combination, factors such as shrinking water and financial resources...

30 CFR 71.602 - Drinking water; distribution.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drinking water; distribution. 71.602 Section 71... Drinking Water § 71.602 Drinking water; distribution. (a) Water shall be piped or transported in sanitary containers. Water systems and appurtenances thereto shall be constructed and maintained in accordance with...

30 CFR 71.602 - Drinking water; distribution.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drinking water; distribution. 71.602 Section 71... Drinking Water § 71.602 Drinking water; distribution. (a) Water shall be piped or transported in sanitary containers. Water systems and appurtenances thereto shall be constructed and maintained in accordance with...

30 CFR 71.602 - Drinking water; distribution.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drinking water; distribution. 71.602 Section 71... Drinking Water § 71.602 Drinking water; distribution. (a) Water shall be piped or transported in sanitary containers. Water systems and appurtenances thereto shall be constructed and maintained in accordance with...

30 CFR 71.602 - Drinking water; distribution.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drinking water; distribution. 71.602 Section 71... Drinking Water § 71.602 Drinking water; distribution. (a) Water shall be piped or transported in sanitary containers. Water systems and appurtenances thereto shall be constructed and maintained in accordance with...

30 CFR 71.602 - Drinking water; distribution.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drinking water; distribution. 71.602 Section 71... Drinking Water § 71.602 Drinking water; distribution. (a) Water shall be piped or transported in sanitary containers. Water systems and appurtenances thereto shall be constructed and maintained in accordance with...

Comparison of Microbial Communities in a Simulated Chloraminated Drinking Water Distribution System Subjected to Episodes of Nitrification

EPA Science Inventory

Bacterial populations were examined in a simulated chloraminated drinking water distribution system. After six months of continuous operation, coupons were incubated in CDC reactors receiving water from the simulated system to study biofilm development. The study was organized ...

Water Quality in Small Community Distribution Systems. A Reference Guide for Operators

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) has developed this reference guide to assist the operators and managers of small- and medium-sized public water systems. This compilation provides a comprehensive picture of the impact of the water distribution system network on dist...

Diversity, community composition, and dynamics of nonpigmented and late-pigmenting rapidly growing mycobacteria in an urban tap water production and distribution system.

PubMed

Dubrou, S; Konjek, J; Macheras, E; Welté, B; Guidicelli, L; Chignon, E; Joyeux, M; Gaillard, J L; Heym, B; Tully, T; Sapriel, G

2013-09-01

Nonpigmented and late-pigmenting rapidly growing mycobacteria (RGM) have been reported to commonly colonize water production and distribution systems. However, there is little information about the nature and distribution of RGM species within the different parts of such complex networks or about their clustering into specific RGM species communities. We conducted a large-scale survey between 2007 and 2009 in the Parisian urban tap water production and distribution system. We analyzed 1,418 water samples from 36 sites, covering all production units, water storage tanks, and distribution units; RGM isolates were identified by using rpoB gene sequencing. We detected 18 RGM species and putative new species, with most isolates being Mycobacterium chelonae and Mycobacterium llatzerense. Using hierarchical clustering and principal-component analysis, we found that RGM were organized into various communities correlating with water origin (groundwater or surface water) and location within the distribution network. Water treatment plants were more specifically associated with species of the Mycobacterium septicum group. On average, M. chelonae dominated network sites fed by surface water, and M. llatzerense dominated those fed by groundwater. Overall, the M. chelonae prevalence index increased along the distribution network and was associated with a correlative decrease in the prevalence index of M. llatzerense, suggesting competitive or niche exclusion between these two dominant species. Our data describe the great diversity and complexity of RGM species living in the interconnected environments that constitute the water production and distribution system of a large city and highlight the prevalence index of the potentially pathogenic species M. chelonae in the distribution network.

Diversity, Community Composition, and Dynamics of Nonpigmented and Late-Pigmenting Rapidly Growing Mycobacteria in an Urban Tap Water Production and Distribution System

PubMed Central

Dubrou, S.; Konjek, J.; Macheras, E.; Welté, B.; Guidicelli, L.; Chignon, E.; Joyeux, M.; Gaillard, J. L.; Heym, B.; Tully, T.

2013-01-01

Nonpigmented and late-pigmenting rapidly growing mycobacteria (RGM) have been reported to commonly colonize water production and distribution systems. However, there is little information about the nature and distribution of RGM species within the different parts of such complex networks or about their clustering into specific RGM species communities. We conducted a large-scale survey between 2007 and 2009 in the Parisian urban tap water production and distribution system. We analyzed 1,418 water samples from 36 sites, covering all production units, water storage tanks, and distribution units; RGM isolates were identified by using rpoB gene sequencing. We detected 18 RGM species and putative new species, with most isolates being Mycobacterium chelonae and Mycobacterium llatzerense. Using hierarchical clustering and principal-component analysis, we found that RGM were organized into various communities correlating with water origin (groundwater or surface water) and location within the distribution network. Water treatment plants were more specifically associated with species of the Mycobacterium septicum group. On average, M. chelonae dominated network sites fed by surface water, and M. llatzerense dominated those fed by groundwater. Overall, the M. chelonae prevalence index increased along the distribution network and was associated with a correlative decrease in the prevalence index of M. llatzerense, suggesting competitive or niche exclusion between these two dominant species. Our data describe the great diversity and complexity of RGM species living in the interconnected environments that constitute the water production and distribution system of a large city and highlight the prevalence index of the potentially pathogenic species M. chelonae in the distribution network. PMID:23835173

Perception of drinking water in the Quebec City region (Canada): the influence of water quality and consumer location in the distribution system.

PubMed

Turgeon, Steve; Rodriguez, Manuel J; Thériault, Marius; Levallois, Patrick

2004-04-01

The purpose of every water utility is to provide consumers with drinking water that is aesthetically acceptable and presents no risk to public health. Several studies have been carried out to analyze people's perception and attitude about the drinking water coming from their water distribution systems. The goal of the present study is to investigate the influence of water quality and the geographic location of consumers within a distribution system on consumer perception of tap water. The study is based on the data obtained from two surveys carried out in municipalities of the Quebec City area (Canada). Three perception variables were used to study consumer perception: general satisfaction, taste satisfaction and risk perception. Data analysis based on logistic regression indicates that water quality variations and geographic location in the distribution system have a significant impact on the consumer perception. This impact appears to be strongly associated with residual chlorine levels. The study also confirms the importance of socio-economic characteristics of consumers on their perception of drinking water quality.

Protozoan Bacterivory and Escherichia coli Survival in Drinking Water Distribution Systems

PubMed Central

Sibille, I.; Sime-Ngando, T.; Mathieu, L.; Block, J. C.

1998-01-01

The development of bacterial communities in drinking water distribution systems leads to a food chain which supports the growth of macroorganisms incompatible with water quality requirements and esthetics. Nevertheless, very few studies have examined the microbial communities in drinking water distribution systems and their trophic relationships. This study was done to quantify the microbial communities (especially bacteria and protozoa) and obtain direct and indirect proof of protozoan feeding on bacteria in two distribution networks, one of GAC water (i.e., water filtered on granular activated carbon) and the other of nanofiltered water. The nanofiltered water-supplied network contained no organisms larger than bacteria, either in the water phase (on average, 5 × 107 bacterial cells liter−1) or in the biofilm (on average, 7 × 106 bacterial cells cm−2). No protozoa were detected in the whole nanofiltered water-supplied network (water plus biofilm). In contrast, the GAC water-supplied network contained bacteria (on average, 3 × 108 cells liter−1 in water and 4 × 107 cells cm−2 in biofilm) and protozoa (on average, 105 cells liter−1 in water and 103 cells cm−2 in biofilm). The water contained mostly flagellates (93%), ciliates (1.8%), thecamoebae (1.6%), and naked amoebae (1.1%). The biofilm had only ciliates (52%) and thecamoebae (48%). Only the ciliates at the solid-liquid interface of the GAC water-supplied network had a measurable grazing activity in laboratory test (estimated at 2 bacteria per ciliate per h). Protozoan ingestion of bacteria was indirectly shown by adding Escherichia coli to the experimental distribution systems. Unexpectedly, E. coli was lost from the GAC water-supplied network more rapidly than from the nanofiltered water-supplied network, perhaps because of the grazing activity of protozoa in GAC water but not in nanofiltered water. Thus, the GAC water-supplied network contained a functional ecosystem with well-established and structured microbial communities, while the nanofiltered water-supplied system did not. The presence of protozoa in drinking water distribution systems must not be neglected because these populations may regulate the autochthonous and allochthonous bacterial populations. PMID:9435076

Protozoan bacterivory and Escherichia coli survival in drinking water distribution systems.

PubMed

Sibille, I; Sime-Ngando, T; Mathieu, L; Block, J C

1998-01-01

The development of bacterial communities in drinking water distribution systems leads to a food chain which supports the growth of macroorganisms incompatible with water quality requirements and esthetics. Nevertheless, very few studies have examined the microbial communities in drinking water distribution systems and their trophic relationships. This study was done to quantify the microbial communities (especially bacteria and protozoa) and obtain direct and indirect proof of protozoan feeding on bacteria in two distribution networks, one of GAC water (i.e., water filtered on granular activated carbon) and the other of nanofiltered water. The nanofiltered water-supplied network contained no organisms larger than bacteria, either in the water phase (on average, 5 x 10(7) bacterial cells liter-1) or in the biofilm (on average, 7 x 10(6) bacterial cells cm-2). No protozoa were detected in the whole nanofiltered water-supplied network (water plus biofilm). In contrast, the GAC water-supplied network contained bacteria (on average, 3 x 10(8) cells liter-1 in water and 4 x 10(7) cells cm-2 in biofilm) and protozoa (on average, 10(5) cells liter-1 in water and 10(3) cells cm-2 in biofilm). The water contained mostly flagellates (93%), ciliates (1.8%), thecamoebae (1.6%), and naked amoebae (1.1%). The biofilm had only ciliates (52%) and thecamoebae (48%). Only the ciliates at the solid-liquid interface of the GAC water-supplied network had a measurable grazing activity in laboratory test (estimated at 2 bacteria per ciliate per h). Protozoan ingestion of bacteria was indirectly shown by adding Escherichia coli to the experimental distribution systems. Unexpectedly, E. coli was lost from the GAC water-supplied network more rapidly than from the nanofiltered water-supplied network, perhaps because of the grazing activity of protozoa in GAC water but not in nanofiltered water. Thus, the GAC water-supplied network contained a functional ecosystem with well-established and structured microbial communities, while the nanofiltered water-supplied system did not. The presence of protozoa in drinking water distribution systems must not be neglected because these populations may regulate the autochthonous and allochthonous bacterial populations.

Bacterial community structure in the drinking water microbiome is governed by filtration processes.

PubMed

Pinto, Ameet J; Xi, Chuanwu; Raskin, Lutgarde

2012-08-21

The bacterial community structure of a drinking water microbiome was characterized over three seasons using 16S rRNA gene based pyrosequencing of samples obtained from source water (a mix of a groundwater and a surface water), different points in a drinking water plant operated to treat this source water, and in the associated drinking water distribution system. Even though the source water was shown to seed the drinking water microbiome, treatment process operations limit the source water's influence on the distribution system bacterial community. Rather, in this plant, filtration by dual media rapid sand filters played a primary role in shaping the distribution system bacterial community over seasonal time scales as the filters harbored a stable bacterial community that seeded the water treatment processes past filtration. Bacterial taxa that colonized the filter and sloughed off in the filter effluent were able to persist in the distribution system despite disinfection of finished water by chloramination and filter backwashing with chloraminated backwash water. Thus, filter colonization presents a possible ecological survival strategy for bacterial communities in drinking water systems, which presents an opportunity to control the drinking water microbiome by manipulating the filter microbial community. Grouping bacterial taxa based on their association with the filter helped to elucidate relationships between the abundance of bacterial groups and water quality parameters and showed that pH was the strongest regulator of the bacterial community in the sampled drinking water system.

Aging Water Infrastructure Program at U.S. EPA: Rehabilitation of Water Distribution and Wastewater Collection Systems

EPA Science Inventory

Several EPA projects are currently underway to encourage technology development and dissemination in key aspects of the condition assessment and rehabilitation of water and wastewater systems. The progress on one of these projects, "Rehabilitation of Water Distribution and Waste...

Fluorescence Sensors for Early Detection of Nitrification in Drinking Water Distribution Systems – Interference Corrections (Abstract)

EPA Science Inventory

Nitrification event detection in chloraminated drinking water distribution systems (DWDSs) remains an ongoing challenge for many drinking water utilities, including Dallas Water Utilities (DWU) and the City of Houston (CoH). Each year, these utilities experience nitrification eve...

Fluorescence Sensors for Early Detection of Nitrification in Drinking Water Distribution Systems – Interference Corrections (Poster)

EPA Science Inventory

Nitrification event detection in chloraminated drinking water distribution systems (DWDSs) remains an ongoing challenge for many drinking water utilities, including Dallas Water Utilities (DWU) and the City of Houston (CoH). Each year, these utilities experience nitrification eve...

Particulate Arsenic Release in a Drinking Water Distribution System

EPA Science Inventory

Trace contaminants, such as arsenic, have been shown to accumulate in solids found in drinking water distribution systems. The obvious concern is that the contaminants in these solids could be released back into the water resulting in elevated levels in a consumer’s tap water. Th...

MIXING IN DISTRIBUTION SYSTEM STORAGE TANKS: ITS EFFECT ON WATER QUALITY

EPA Science Inventory

Nearly all distribution systems in the US include storage tanks and reservoirs. They are the most visible components of a wate distribution system but are generally the least understood in terms of their impact on water quality. Long residence times in storage tanks can have nega...

Comparison of Microbial Communities in a Simulated Chloraminated Drinking Water Distribution System Subjected to Episodes of Nitrification (poster)

EPA Science Inventory

Bacterial populations were examined in a simulated chloraminated drinking water distribution system (i.e. PVC pipe loop). After six months of continuous operation, coupons were incubated in CDC reactors receiving water from the simulated system to study biofilm development. The s...

IMPACT ON WATER DISTRIBUTION SYSTEM BIOFILM DENSITIES FROM REVERSE OSMOSIS MEMBRANE TREATMENT OF SUPPLY WATER

EPA Science Inventory

The quality of potable water is such that the concentration of nutrients available for growth of microorganisms within distribution systems is limited. In such systems carbon is often the growth limiting nutrient. Research conducted in the Netherlands has indicated that low level...

USE OF NETWORK MODELS FOR ESTIMATING EXPOSURE OF CONSUMERS TO CONTAMINANTS IN DRINKING WATER DISTRIBUTION SYSTEMS

EPA Science Inventory

The presence of contaminants in a drinking water distribution system can result in exposure of consumers to contaminated water. Whether the contaminants result from waterborne outbreaks that accidentally enter the system or through purposeful acts, the movement of the resulting ...

Operation of remote mobile sensors for security of drinking water distribution systems.

PubMed

Perelman, By Lina; Ostfeld, Avi

2013-09-01

The deployment of fixed online water quality sensors in water distribution systems has been recognized as one of the key components of contamination warning systems for securing public health. This study proposes to explore how the inclusion of mobile sensors for inline monitoring of various water quality parameters (e.g., residual chlorine, pH) can enhance water distribution system security. Mobile sensors equipped with sampling, sensing, data acquisition, wireless transmission and power generation systems are being designed, fabricated, and tested, and prototypes are expected to be released in the very near future. This study initiates the development of a theoretical framework for modeling mobile sensor movement in water distribution systems and integrating the sensory data collected from stationary and non-stationary sensor nodes to increase system security. The methodology is applied and demonstrated on two benchmark networks. Performance of different sensor network designs are compared for fixed and combined fixed and mobile sensor networks. Results indicate that complementing online sensor networks with inline monitoring can increase detection likelihood and decrease mean time to detection. Copyright © 2013 Elsevier Ltd. All rights reserved.

Spatial-Temporal Survey and Occupancy-Abundance Modeling To Predict Bacterial Community Dynamics in the Drinking Water Microbiome

PubMed Central

Pinto, Ameet J.; Schroeder, Joanna; Lunn, Mary; Sloan, William

2014-01-01

ABSTRACT Bacterial communities migrate continuously from the drinking water treatment plant through the drinking water distribution system and into our built environment. Understanding bacterial dynamics in the distribution system is critical to ensuring that safe drinking water is being supplied to customers. We present a 15-month survey of bacterial community dynamics in the drinking water system of Ann Arbor, MI. By sampling the water leaving the treatment plant and at nine points in the distribution system, we show that the bacterial community spatial dynamics of distance decay and dispersivity conform to the layout of the drinking water distribution system. However, the patterns in spatial dynamics were weaker than those for the temporal trends, which exhibited seasonal cycling correlating with temperature and source water use patterns and also demonstrated reproducibility on an annual time scale. The temporal trends were driven by two seasonal bacterial clusters consisting of multiple taxa with different networks of association within the larger drinking water bacterial community. Finally, we show that the Ann Arbor data set robustly conforms to previously described interspecific occupancy abundance models that link the relative abundance of a taxon to the frequency of its detection. Relying on these insights, we propose a predictive framework for microbial management in drinking water systems. Further, we recommend that long-term microbial observatories that collect high-resolution, spatially distributed, multiyear time series of community composition and environmental variables be established to enable the development and testing of the predictive framework. PMID:24865557

ANIMATION AND VISUALIZATION OF WATER QUALITY IN DISTRIBUTION SYSTEMS

EPA Science Inventory

Water may undergo a number of changes in the distribution system, making the quality of the water at the customer's tap different from the quality of the water that leaves the treatment plant. Such changes in quality may be caused by chemical or biological variations or by a loss...

EFFECTS OF MIXING AND AGING ON WATER QUALITY IN DISTRIBUTION SYSTEM STORAGE FACILITIES

EPA Science Inventory

Aging of water in distribution system storage facilities can lead to deterioration of the water quality due to loss of disinfectant residual and bacterial regrowth. Facilities should be operated to insure that the age of the water is not excessive taking into account the quality...

Diversity of free-living amoebae in a dual distribution (potable and recycled) water system

EPA Science Inventory

Free-living amoebae are known to facilitate the growth of water associated pathogens. This study, for the first time, explored the diversity of free-living amoebae in a dual distribution (potable and recycled) water system in Rouse Hill NSW, Australia. Water and biofilm samples w...

Drinking Water Microbiome as a Screening Tool for Nitrification in Chloraminated Drinking Water Distribution Systems (abstract)

EPA Science Inventory

Many water utilities in the US using chloramine as disinfectant treatment in their distribution systems have experienced nitrification episodes, which detrimentally impact the water quality. Here, we used 16S rRNA sequencing data to generate high-resolution taxonomic profiles of...

MODELING THE IMPACTS OF FIRE FLOWS ON DISTRIBUTION SYSTEM WATER QUALITY, DESIGN AND OPERATION

EPA Science Inventory

In most water distribution systems, a significant amount of the piping and storage capacity is used to provide adequate quantities of water during fire conditions. This increased capacity results in higher capital costs and potential negative impacts on water quality due to longe...

Silver Ion Biocide Delivery System for Water Disinfection

NASA Technical Reports Server (NTRS)

Slote, Benjamin M.; Salley, Edward; Carr, Daniel; Kimble, Michael C.; Adam, Niklas

2016-01-01

U.S. space exploration missions have long considered returning to the Moon and exploration of Mars that challenge life support systems. For these long duration missions, there is interest in replacing the iodine water treatment system with ionic silver, a proven biocide. For long duration exploration missions, it is imperative that an effective biocide be used that prevents microbial growth, biofilm formation, and microbially induced corrosion in the water storage and distribution systems while minimizing logistical supply requirements associated with the biocide delivery system. Two biocide delivery systems have been developed that electrochemically produce silver ions for disinfecting water throughout the water storage and distribution system. One system uses a newly developed hybrid micro-filtration and ion-exchange membrane to produce an abundance of silver ions at the 1000 ppb level upstream in the water distribution system to prevent biofilm growth. This is followed by a downstream collection module that electrochemically removes these silver ions before the water is discharged. Another approach uses a membraneless reactor to produce a 1000 ppb silver ion concentration level that also has a mechanically driven electrode cleaning mechanism that removes oxide films ensuring long life operation. By maintaining a sufficiently high level of silver ions throughout the water storage and distribution system, biofilm formation is suppressed. This approach overcomes present concerns where spurious silver deposition occurs on the container and flow line surfaces thus lowering the silver ion concentration to unsatisfactory disinfection levels.

Demonstration of a Model-Based Technology for Monitoring Water Quality and Corrosion in Water-Distribution systems

DTIC Science & Technology

2016-12-01

Kamojjala, 2014, “Real-Time M0deling of Water Distribution Systems: A Case Study ,” Journal AWWA, Vol. 106, No. 9 (September 2014.) Feinauer, Lynn R...Quality and Corrosion in Water-Distribution Systems Final Report on Project F07-AR05 Co ns tr uc tio n En gi ne er in g R es ea rc h La bo ra to...Final Report on Project F07-AR05 Vicki L. Van Blaricum Construction Engineering Research Laboratory U.S. Army Engineer Research and Development Center

Monochloramine use for prevention of Legionella in hospital water systems.

PubMed

Kandiah, Sheetal; Yassin, Mohamed H; Stout, Janet

2013-06-01

Eradication of Legionella species from water distribution systems especially in hospital settings has proven to be challenging. Legionella species causes Legionnaire's disease that is a potentially fatal respiratory disease often acquired through the aerosolization of contaminated water. Monochloramine has been used successfully in the municipal water systems to eradicate Legionella and there is currently limited data to support its use in the hospital setting. This technology appears to be affordable, safe and effective at penetrating biofilm in water distribution systems.

Parametric distribution approach for flow availability in small hydro potential analysis

NASA Astrophysics Data System (ADS)

Abdullah, Samizee; Basri, Mohd Juhari Mat; Jamaluddin, Zahrul Zamri; Azrulhisham, Engku Ahmad; Othman, Jamel

2016-10-01

Small hydro system is one of the important sources of renewable energy and it has been recognized worldwide as clean energy sources. Small hydropower generation system uses the potential energy in flowing water to produce electricity is often questionable due to inconsistent and intermittent of power generated. Potential analysis of small hydro system which is mainly dependent on the availability of water requires the knowledge of water flow or stream flow distribution. This paper presented the possibility of applying Pearson system for stream flow availability distribution approximation in the small hydro system. By considering the stochastic nature of stream flow, the Pearson parametric distribution approximation was computed based on the significant characteristic of Pearson system applying direct correlation between the first four statistical moments of the distribution. The advantage of applying various statistical moments in small hydro potential analysis will have the ability to analyze the variation shapes of stream flow distribution.

Water Loss Reduction as the Basis of Good Water Supply Companies' Management

NASA Astrophysics Data System (ADS)

Ociepa-Kubicka, Agnieszka; Wilczak, Krzysztof

2017-10-01

Companies using water distribution systems to reduce the operating costs and increase the reliability of water supply systems, as well as to protect disposable water resources, must search for ways to reduce water losses. The article points out the economic and environmental aspects of water losses. The possibilities of using international water loss assessment standards have been analysed. The reflections presented in the paper refer to the current trends and world standards in the field of water distribution systems management. The article presents the results and analysis of water losses for the water supply network operated by the Water Supply and Sewerage Company in Gliwice (Przedsiębiorstwo Wodociągów i Kanalizacji w Gliwicach, PWiK). The losses were determined on the basis of numerous indicators and compared with other distribution systems. At present, most indicators of water loss are at a very good or good level. The Infrastructure Leakage Index (ILI), as one of the most reliable loss indicators for the surveyed distribution system, assumed values from 3.33 in 2012 to 2.06 in 2015. The recent drop in ILI values indicates the effectiveness of the Company's strategy for water leakage reduction. The success comprises a number of undertakings, such as ongoing monitoring, pressure reduction and stabilisation, repairs and replacement of the most emergency wires.

Identification and characterization of steady and occluded water in drinking water distribution systems.

PubMed

Tong, Huiyan; Zhao, Peng; Zhang, Hongwei; Tian, Yimei; Chen, Xi; Zhao, Weigao; Li, Mei

2015-01-01

Deterioration and leakage of drinking water in distribution systems have been a major issue in the water industry for years, which are associated with corrosion. This paper discovers that occluded water in the scales of the pipes has an acidic environment and high concentration of iron, manganese, chloride, sulfate and nitrate, which aggravates many pipeline leakage accidents. Six types of water samples have been analyzed under the flowing and stagnant periods. Both the water in the exterior of the tubercles and stagnant water carry suspended iron particles, which explains the occurrence of "red water" when the system hydraulic conditions change. Nitrate is more concentrated in occluded water under flowing condition in comparison with that in flowing water. However, the concentration of nitrate in occluded water under stagnant condition is found to be less than that in stagnant water. A high concentration of manganese is found to exist in steady water, occluded water and stagnant water. These findings impact secondary pollution and the corrosion of pipes and containers used in drinking water distribution systems. The unique method that taking occluded water from tiny holes which were drilled from the pipes' exteriors carefully according to the positions of corrosion scales has an important contribution to research on corrosion in distribution systems. And this paper furthers our understanding and contributes to the growing body of knowledge regarding occluded environments in corrosion scales. Copyright © 2014 Elsevier Ltd. All rights reserved.

Monochloramine Cometabolism by Ammonia-Oxidizing Bacteria. Report #4341

EPA Science Inventory

Chloramine use is widespread in United States (US) drinking water distribution systems as a secondary disinfectant. In a recent survey of water utilities, 30% of the respondents used chloramines to maintain distribution system residual (AWWA Water Quality and Technology Division...

EPA Distribution System (DS) Research as It Relates to the TCRDS and the DS Research Partnership ..and more

EPA Science Inventory

An overview of Water Supply and Water Research Division (WSWRD) distribution system water quality research was provided. Specifically, the research topics of corrosion, nitrification, biofilms and contaminant accumulation were discussed.

Iron and copper release in drinking-water distribution systems.

PubMed

Shi, Baoyou; Taylor, James S

2007-09-01

A large-scale pilot study was carried out to evaluate the impacts of changes in water source and treatment process on iron and copper release in water distribution systems. Finished surface waters, groundwaters, and desalinated waters were produced with seven different treatment systems and supplied to 18 pipe distribution systems (PDSs). The major water treatment processes included lime softening, ferric sulfate coagulation, reverse osmosis, nanofiltration, and integrated membrane systems. PDSs were constructed from PVC, lined cast iron, unlined cast iron, and galvanized pipes. Copper pipe loops were set up for corrosion monitoring. Results showed that surface water after ferric sulfate coagulation had low alkalinity and high sulfates, and consequently caused the highest iron release. Finished groundwater treated by conventional method produced the lowest iron release but the highest copper release. The iron release of desalinated water was relatively high because of the water's high chloride level and low alkalinity. Both iron and copper release behaviors were influenced by temperature.

A Decision-Support System for Sustainable Water Distribution System Planning.

PubMed

Freund, Alina; Aydin, Nazli Yonca; Zeckzer, Dirk; Hagen, Hans

2017-01-01

An interactive decision-support system (DSS) can help experts prepare water resource management plans for decision makers and stakeholders. The design of the proposed prototype incorporates visualization techniques such as circle views, grid layout, small multiple maps, and node simplification to improve the data readability of water distribution systems. A case study with three urban water management and sanitary engineering experts revealed that the proposed DSS is satisfactory, efficient, and effective.

Detection and Characterization of Malathion Adherence to Piping Materials Used in Water Distribution Systems

DTIC Science & Technology

2015-03-26

photoelectron spectroscopy was also used in an effort to detect shifts in the adsorptive spectra that appeared to be attributable to the presence of trace ... DETECTION AND CHARACTERIZATION OF MALATHION ADHERENCE TO PIPING MATERIALS USED IN WATER DISTRIBUTION... DETECTION AND CHARACTERIZATION OF MALATHION ADHERENCE TO PIPING MATERIALS USED IN WATER DISTRIBUTION SYSTEMS THESIS Presented to the Faculty

Prediction of contaminant fate and transport in potable water systems using H2OFate

NASA Astrophysics Data System (ADS)

Devarakonda, Venkat; Manickavasagam, Sivakumar; VanBlaricum, Vicki; Ginsberg, Mark

2009-05-01

BlazeTech has recently developed a software called H2OFate to predict the fate and transport of chemical and biological contaminants in water distribution systems. This software includes models for the reactions of these contaminants with residual disinfectant in bulk water and at the pipe wall, and their adhesion/reactions with the pipe walls. This software can be interfaced with sensors through SCADA systems to monitor water distribution networks for contamination events and activate countermeasures, as needed. This paper presents results from parametric calculations carried out using H2OFate for a simulated contaminant release into a sample water distribution network.

THE EFFECT OF CHLORIDE AND ORTHOPHOSPHATE ON THE RELEASE OF IRON FROM A DRINKING WATER DISTRIBUTION SYSTEM CAST IRON PIPE

EPA Science Inventory

"Colored water" describes the appearance of drinking water that contains suspended particulate iron although the actual suspension color may be light yellow to red depending on water chemistry and particle properties. The release of iron from distribution system materials such a...

THE EFFECT OF CHLORIDE AND ORTHOPHOSPHATE ON THE RELEASE OF IRON FROM A DRINKING WATER DISTRIBUTION SYSTEM CAST IRON PIPE

EPA Science Inventory

Colored water" describes the appearance of drinking water that contains suspended particulate iron although the actual suspension color may be light yellow to red depending on water chemistry and particle properties. The release of iron from distribution system materials such as...

Microbial Community Profile of a Lead Service Line Removed from a Drinking Water Distribution System

EPA Science Inventory

A corroded lead water pipe was removed from a drinking water distribution system and the microbial community was profiled using 16S rDNA techniques. This is the first report of the characterization of biofilm on a surface of a corroded lead drinking water pipe. The majority of ...

The Accumulation of Radioactive Contaminants in Drinking Water Distribution Systems

EPA Science Inventory

The accumulation of trace contaminants in drinking water distribution systems has been documented and the subsequent release of the contaminants back to the water is a potential exposure pathway. Radioactive contaminants are of particular concern because of their known health eff...

BIOLOGICAL FILTRATION FOR THE NITRIFICATION OF EXCESSIVE LEVELS OF FREE AMMONIA

EPA Science Inventory

Ammonia in source waters can cause water treatment and distribution system problems. Research on the presence of ammonia in drinking water distribution systems for example has suggested some correlation between excess ammonia and increased biological activity (Servais, 1995; Wilc...

[Influence of water source switching on water quality in drinking water distribution system].

PubMed

Wang, Yang; Niu, Zhang-bin; Zhang, Xiao-jian; Chen, Chao; He, Wen-jie; Han, Hong-da

2007-10-01

This study investigates the regularity of the change on the physical and chemical water qualities in the distribution system during the process of water source switching in A city. Due to the water source switching, the water quality is chemical-astable. Because of the differences between the two water sources, pH reduced from 7.54 to 7.18, alkalinity reduced from 188 mg x L(-1) to 117 mg x L(-1), chloride (Cl(-)) reduced from 310 mg x L(-1) to 132 mg x L(-1), conductance reduced from 0.176 S x m(-1) to 0.087 S x m(-1) and the ions of calcium and magnesium reduced to 15 mg x L(-1) and 11 mg x L(-1) respectively. Residual chlorine changed while the increase of the chlorine demand and the water quantity decreasing at night, and the changes of pH, alkalinity and residual chlorine brought the iron increased to 0.4 mg x L(-1) at the tiptop, which was over the standard. The influence of the change of the water parameters on the water chemical-stability in the drinking water distribution system is analyzed, and the controlling countermeasure is advanced: increasing pH, using phosphate and enhancing the quality of the water in distribution system especially the residual chlorine.

Transformation of Bisphenol A in Water Distribution Systems, A Pilot-scale Study

EPA Science Inventory

Halogenations of bisphenol A (BPA) in a pilot-scale water distribution system (WDS) of cement-lined ductile cast iron pipe were investigated under the condition: pH 7.3±0.3, water flow velocity of 1.0 m/s, and 25 °C ± 1 °C in water temperature. The testing water was chlorinated f...

Effects of the Shuttle Orbiter fuselage and elevon on the molecular distribution of water vapor from the flash evaporator system

NASA Technical Reports Server (NTRS)

Richmond, R. G.; Kelso, R. M.

1980-01-01

A concern has arisen regarding the emissive distribution of water molecules from the shuttle orbiter flash evaporator system (FES). The role of the orbiter fuselage and elevon in affecting molecular scattering distributions was nuclear. The effect of these components were evaluated. Molecular distributions of the water vapor effluents from the FE were measured. These data were compared with analytically predicted values and the resulting implications were calculated.

Variation of levels and distribution of N-nitrosamines in different seasons in drinking waters of East China.

PubMed

Li, Ting; Yu, Dian; Xian, Qiming; Li, Aimin; Sun, Cheng

2015-08-01

We surveyed the occurrence of nine N-nitrosamine species in ten bottled drinking waters from supermarket and other water samples including raw waters, finished waters, and distribution system waters from nine municipal drinking water treatment plants in eight cities of Jiangsu Province, East China. N-nitrosodimethylamine (NDMA) was detected in one of ten bottled drinking water samples at concentration of 4.8 ng/L and N-nitrosomorpholine (NMor) was detected in four of the ten bottles with an average concentration and a standard deviation of 16 ± 15 ng/L. The levels of nitrosamines in the distribution system water samples collected during summer season ranged from below detection limit (BDL) to 5.4 ng/L for NDMA, BDL to 9.5 ng/L for N-nitrosomethylethylamine (NMEA), BDL to 2.7 ng/L for N-nitrosodiethylamine (NDEA) and BDL to 8.5 ng/L for N-nitrosopyrrolidine (NPyr). Samples of distribution system waters collected in winter season had levels of nitrosamines ranged from BDL to 45 ng/L for NDMA, BDL to 5.2 ng/L for NPyr, and BDL to 309 ng/L for N-nitrosopiperidine (NPip). A positive correlation of the concentration of NDMA as well as the total nine N-nitrosamines between finished waters and distribution system waters was observed. Both dissolved organic carbon and nitrite were found to correlate linearly with N-nitrosamine levels in raw waters.

Analysis of residual chlorine in simple drinking water distribution system with intermittent water supply

NASA Astrophysics Data System (ADS)

Goyal, Roopali V.; Patel, H. M.

2015-09-01

Knowledge of residual chlorine concentration at various locations in drinking water distribution system is essential final check to the quality of water supplied to the consumers. This paper presents a methodology to find out the residual chlorine concentration at various locations in simple branch network by integrating the hydraulic and water quality model using first-order chlorine decay equation with booster chlorination nodes for intermittent water supply. The explicit equations are developed to compute the residual chlorine in network with a long distribution pipe line at critical nodes. These equations are applicable to Indian conditions where intermittent water supply is the most common system of water supply. It is observed that in intermittent water supply, the residual chlorine at farthest node is sensitive to water supply hours and travelling time of chlorine. Thus, the travelling time of chlorine can be considered to justify the requirement of booster chlorination for intermittent water supply.

PHYLOGENETIC DIVERSITY IN DRINKING WATER BACTERIA IN A DISTRIBUTION SYSTEM SIMULATOR

EPA Science Inventory

This work was carried out to characterize the composition of microbial populations in a distribution system simulator (DSS) by direct sequence analysis of 16S rDNA clone libraries. Bacterial populations were examined in chlorinated distribution water and chloraminated DSS feed an...

7 CFR 1717.851 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... distribution system means any system of community infrastructure whose primary function is the distribution of... communication system means any system of community infrastructure whose primary function is the provision of... primary function is the supplying of water and/or the collection and treatment of waste water and whose...

7 CFR 1717.851 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... distribution system means any system of community infrastructure whose primary function is the distribution of... communication system means any system of community infrastructure whose primary function is the provision of... primary function is the supplying of water and/or the collection and treatment of waste water and whose...

7 CFR 1717.851 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... distribution system means any system of community infrastructure whose primary function is the distribution of... communication system means any system of community infrastructure whose primary function is the provision of... primary function is the supplying of water and/or the collection and treatment of waste water and whose...

7 CFR 1717.851 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... distribution system means any system of community infrastructure whose primary function is the distribution of... communication system means any system of community infrastructure whose primary function is the provision of... primary function is the supplying of water and/or the collection and treatment of waste water and whose...

7 CFR 1717.851 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... distribution system means any system of community infrastructure whose primary function is the distribution of... communication system means any system of community infrastructure whose primary function is the provision of... primary function is the supplying of water and/or the collection and treatment of waste water and whose...

A neural network approach to burst detection.

PubMed

Mounce, S R; Day, A J; Wood, A S; Khan, A; Widdop, P D; Machell, J

2002-01-01

This paper describes how hydraulic and water quality data from a distribution network may be used to provide a more efficient leakage management capability for the water industry. The research presented concerns the application of artificial neural networks to the issue of detection and location of leakage in treated water distribution systems. An architecture for an Artificial Neural Network (ANN) based system is outlined. The neural network uses time series data produced by sensors to directly construct an empirical model for predication and classification of leaks. Results are presented using data from an experimental site in Yorkshire Water's Keighley distribution system.

[Monitoring microbiological safety of small systems of water distribution. Comparison of two sampling programs in a town in central Italy].

PubMed

Papini, Paolo; Faustini, Annunziata; Manganello, Rosa; Borzacchi, Giancarlo; Spera, Domenico; Perucci, Carlo A

2005-01-01

To determine the frequency of sampling in small water distribution systems (<5,000 inhabitants) and compare the results according to different hypotheses in bacteria distribution. We carried out two sampling programs to monitor the water distribution system in a town in Central Italy between July and September 1992; the Poisson distribution assumption implied 4 water samples, the assumption of negative binomial distribution implied 21 samples. Coliform organisms were used as indicators of water safety. The network consisted of two pipe rings and two wells fed by the same water source. The number of summer customers varied considerably from 3,000 to 20,000. The mean density was 2.33 coliforms/100 ml (sd= 5.29) for 21 samples and 3 coliforms/100 ml (sd= 6) for four samples. However the hypothesis of homogeneity was rejected (p-value <0.001) and the probability of II type error with the assumption of heterogeneity was higher with 4 samples (beta= 0.24) than with 21 (beta= 0.05). For this small network, determining the samples' size according to heterogeneity hypothesis strengthens the statement that water is drinkable compared with homogeneity assumption.

Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

PubMed

Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

2016-01-01

Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to maintain good drinking water microbial quality up to consumer's tap. A new definition and methodological approach for biological stability is proposed.

Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

PubMed Central

Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

2016-01-01

Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to maintain good drinking water microbial quality up to consumer’s tap. A new definition and methodological approach for biological stability is proposed. PMID:26870010

Factors Influencing Bacterial Diversity and Community Composition in Municipal Drinking Waters in the Ohio River Basin, USA

PubMed Central

Stanish, Lee F.; Hull, Natalie M.; Robertson, Charles E.; Harris, J. Kirk; Stevens, Mark J.; Spear, John R.; Pace, Norman R.

2016-01-01

The composition and metabolic activities of microbes in drinking water distribution systems can affect water quality and distribution system integrity. In order to understand regional variations in drinking water microbiology in the upper Ohio River watershed, the chemical and microbiological constituents of 17 municipal distribution systems were assessed. While sporadic variations were observed, the microbial diversity was generally dominated by fewer than 10 taxa, and was driven by the amount of disinfectant residual in the water. Overall, Mycobacterium spp. (Actinobacteria), MLE1-12 (phylum Cyanobacteria), Methylobacterium spp., and sphingomonads were the dominant taxa. Shifts in community composition from Alphaproteobacteria and Betaproteobacteria to Firmicutes and Gammaproteobacteria were associated with higher residual chlorine. Alpha- and beta-diversity were higher in systems with higher chlorine loads, which may reflect changes in the ecological processes structuring the communities under different levels of oxidative stress. These results expand the assessment of microbial diversity in municipal distribution systems and demonstrate the value of considering ecological theory to understand the processes controlling microbial makeup. Such understanding may inform the management of municipal drinking water resources. PMID:27362708

Factors Influencing Bacterial Diversity and Community Composition in Municipal Drinking Waters in the Ohio River Basin, USA.

PubMed

Stanish, Lee F; Hull, Natalie M; Robertson, Charles E; Harris, J Kirk; Stevens, Mark J; Spear, John R; Pace, Norman R

2016-01-01

The composition and metabolic activities of microbes in drinking water distribution systems can affect water quality and distribution system integrity. In order to understand regional variations in drinking water microbiology in the upper Ohio River watershed, the chemical and microbiological constituents of 17 municipal distribution systems were assessed. While sporadic variations were observed, the microbial diversity was generally dominated by fewer than 10 taxa, and was driven by the amount of disinfectant residual in the water. Overall, Mycobacterium spp. (Actinobacteria), MLE1-12 (phylum Cyanobacteria), Methylobacterium spp., and sphingomonads were the dominant taxa. Shifts in community composition from Alphaproteobacteria and Betaproteobacteria to Firmicutes and Gammaproteobacteria were associated with higher residual chlorine. Alpha- and beta-diversity were higher in systems with higher chlorine loads, which may reflect changes in the ecological processes structuring the communities under different levels of oxidative stress. These results expand the assessment of microbial diversity in municipal distribution systems and demonstrate the value of considering ecological theory to understand the processes controlling microbial makeup. Such understanding may inform the management of municipal drinking water resources.

Water Purification, Distribution and Sewage Disposal. Appropriate Technologies for Development. Reprint R-29.

ERIC Educational Resources Information Center

1979

This document, designed to serve as a training manual for technical instructors and as a field resource reference for Peace Corps volunteers, consists of nine units. Unit topics focus on: (1) water supply sources; (2) water treatment; (3) planning water distribution systems; (4) characteristics of an adequate system; (5) construction techniques;…

THE EFFECT OF CHLORIDE AND ORTHOPHOSPHATE ON THE RELEASE OF IRON FROM DRINKING WATER DISTRIBUTION SYSTEM CAST IRON MAIN

EPA Science Inventory

“Colored water” resulting from suspended iron particles is a common drinking water consumer complaint which is largely impacted by water chemistry. A bench scale study, performed on a 90 year-old corroded cast-iron pipe section removed from a drinking water distribution system, w...

A Comprehensive Investigation of Copper Pitting Corrosion in a Drinking Water Distribution System

EPA Science Inventory

Copper pipe pitting is a complicated corrosion process for which exact causes and solutions are uncertain. This paper presents the findings of a comprehensive investigation of a cold water copper pitting corrosion problem in a drinking water distribution system, including a refi...

ASSESSING AND PREVENTING THE SPREAD OF CONTAMINANTS IN A DRINKING WATER DISTRIBUTION SYSTEM

EPA Science Inventory

Remote monitoring data, field studies, and the modeling software ? EPANET, can be used by drinking water utilities and consulting engineers to predict flow dynamics and information on the spatial distribution and concentration of contaminants in a drinking water system. A field ...

Using WNTR to Model Water Distribution System Resilience

EPA Science Inventory

The Water Network Tool for Resilience (WNTR) is a new open source Python package developed by the U.S. Environmental Protection Agency and Sandia National Laboratories to model and evaluate resilience of water distribution systems. WNTR can be used to simulate a wide range of di...

Spatial Description of Drinking Water Bacterial Community Structures in Bulk Water Samples Collected in a Metropolitan Distribution System

EPA Science Inventory

The description of microorganisms inhabiting drinking water distribution systems has commonly been performed using techniques that are biased towards easy to culture bacterial populations. As most environmental microorganisms cannot be grown on artificial media, our understanding...

WATER DISTRIBUTION SYSTEMS: A SPATIAL AND COST EVALUATION

EPA Science Inventory

Problems associated with maintaining and replacing water supply distribution systems are reviewed. Some of these problems are associated with public health, economic and spatial development of the community, and costs of repair and replacement of system components. A repair frequ...

Distributed software framework and continuous integration in hydroinformatics systems

NASA Astrophysics Data System (ADS)

Zhou, Jianzhong; Zhang, Wei; Xie, Mengfei; Lu, Chengwei; Chen, Xiao

2017-08-01

When encountering multiple and complicated models, multisource structured and unstructured data, complex requirements analysis, the platform design and integration of hydroinformatics systems become a challenge. To properly solve these problems, we describe a distributed software framework and it’s continuous integration process in hydroinformatics systems. This distributed framework mainly consists of server cluster for models, distributed database, GIS (Geographic Information System) servers, master node and clients. Based on it, a GIS - based decision support system for joint regulating of water quantity and water quality of group lakes in Wuhan China is established.

Biological instability in a chlorinated drinking water distribution network.

PubMed

Nescerecka, Alina; Rubulis, Janis; Vital, Marius; Juhna, Talis; Hammes, Frederik

2014-01-01

The purpose of a drinking water distribution system is to deliver drinking water to the consumer, preferably with the same quality as when it left the treatment plant. In this context, the maintenance of good microbiological quality is often referred to as biological stability, and the addition of sufficient chlorine residuals is regarded as one way to achieve this. The full-scale drinking water distribution system of Riga (Latvia) was investigated with respect to biological stability in chlorinated drinking water. Flow cytometric (FCM) intact cell concentrations, intracellular adenosine tri-phosphate (ATP), heterotrophic plate counts and residual chlorine measurements were performed to evaluate the drinking water quality and stability at 49 sampling points throughout the distribution network. Cell viability methods were compared and the importance of extracellular ATP measurements was examined as well. FCM intact cell concentrations varied from 5×10(3) cells mL(-1) to 4.66×10(5) cells mL(-1) in the network. While this parameter did not exceed 2.1×10(4) cells mL(-1) in the effluent from any water treatment plant, 50% of all the network samples contained more than 1.06×10(5) cells mL(-1). This indisputably demonstrates biological instability in this particular drinking water distribution system, which was ascribed to a loss of disinfectant residuals and concomitant bacterial growth. The study highlights the potential of using cultivation-independent methods for the assessment of chlorinated water samples. In addition, it underlines the complexity of full-scale drinking water distribution systems, and the resulting challenges to establish the causes of biological instability.

Biological Instability in a Chlorinated Drinking Water Distribution Network

PubMed Central

Nescerecka, Alina; Rubulis, Janis; Vital, Marius; Juhna, Talis; Hammes, Frederik

2014-01-01

The purpose of a drinking water distribution system is to deliver drinking water to the consumer, preferably with the same quality as when it left the treatment plant. In this context, the maintenance of good microbiological quality is often referred to as biological stability, and the addition of sufficient chlorine residuals is regarded as one way to achieve this. The full-scale drinking water distribution system of Riga (Latvia) was investigated with respect to biological stability in chlorinated drinking water. Flow cytometric (FCM) intact cell concentrations, intracellular adenosine tri-phosphate (ATP), heterotrophic plate counts and residual chlorine measurements were performed to evaluate the drinking water quality and stability at 49 sampling points throughout the distribution network. Cell viability methods were compared and the importance of extracellular ATP measurements was examined as well. FCM intact cell concentrations varied from 5×103 cells mL−1 to 4.66×105 cells mL−1 in the network. While this parameter did not exceed 2.1×104 cells mL−1 in the effluent from any water treatment plant, 50% of all the network samples contained more than 1.06×105 cells mL−1. This indisputably demonstrates biological instability in this particular drinking water distribution system, which was ascribed to a loss of disinfectant residuals and concomitant bacterial growth. The study highlights the potential of using cultivation-independent methods for the assessment of chlorinated water samples. In addition, it underlines the complexity of full-scale drinking water distribution systems, and the resulting challenges to establish the causes of biological instability. PMID:24796923

Dynamics of Biofilm Regrowth in Drinking Water Distribution Systems.

PubMed

Douterelo, I; Husband, S; Loza, V; Boxall, J

2016-07-15

The majority of biomass within water distribution systems is in the form of attached biofilm. This is known to be central to drinking water quality degradation following treatment, yet little understanding of the dynamics of these highly heterogeneous communities exists. This paper presents original information on such dynamics, with findings demonstrating patterns of material accumulation, seasonality, and influential factors. Rigorous flushing operations repeated over a 1-year period on an operational chlorinated system in the United Kingdom are presented here. Intensive monitoring and sampling were undertaken, including time-series turbidity and detailed microbial analysis using 16S rRNA Illumina MiSeq sequencing. The results show that bacterial dynamics were influenced by differences in the supplied water and by the material remaining attached to the pipe wall following flushing. Turbidity, metals, and phosphate were the main factors correlated with the distribution of bacteria in the samples. Coupled with the lack of inhibition of biofilm development due to residual chlorine, this suggests that limiting inorganic nutrients, rather than organic carbon, might be a viable component in treatment strategies to manage biofilms. The research also showed that repeat flushing exerted beneficial selective pressure, giving another reason for flushing being a viable advantageous biofilm management option. This work advances our understanding of microbiological processes in drinking water distribution systems and helps inform strategies to optimize asset performance. This research provides novel information regarding the dynamics of biofilm formation in real drinking water distribution systems made of different materials. This new knowledge on microbiological process in water supply systems can be used to optimize the performance of the distribution network and to guarantee safe and good-quality drinking water to consumers. Copyright © 2016 Douterelo et al.

Dynamics of Biofilm Regrowth in Drinking Water Distribution Systems

PubMed Central

Husband, S.; Loza, V.; Boxall, J.

2016-01-01

ABSTRACT The majority of biomass within water distribution systems is in the form of attached biofilm. This is known to be central to drinking water quality degradation following treatment, yet little understanding of the dynamics of these highly heterogeneous communities exists. This paper presents original information on such dynamics, with findings demonstrating patterns of material accumulation, seasonality, and influential factors. Rigorous flushing operations repeated over a 1-year period on an operational chlorinated system in the United Kingdom are presented here. Intensive monitoring and sampling were undertaken, including time-series turbidity and detailed microbial analysis using 16S rRNA Illumina MiSeq sequencing. The results show that bacterial dynamics were influenced by differences in the supplied water and by the material remaining attached to the pipe wall following flushing. Turbidity, metals, and phosphate were the main factors correlated with the distribution of bacteria in the samples. Coupled with the lack of inhibition of biofilm development due to residual chlorine, this suggests that limiting inorganic nutrients, rather than organic carbon, might be a viable component in treatment strategies to manage biofilms. The research also showed that repeat flushing exerted beneficial selective pressure, giving another reason for flushing being a viable advantageous biofilm management option. This work advances our understanding of microbiological processes in drinking water distribution systems and helps inform strategies to optimize asset performance. IMPORTANCE This research provides novel information regarding the dynamics of biofilm formation in real drinking water distribution systems made of different materials. This new knowledge on microbiological process in water supply systems can be used to optimize the performance of the distribution network and to guarantee safe and good-quality drinking water to consumers. PMID:27208119

A software framework for assessing the resilience of drinking water systems to disasters with an example earthquake case study

DOE PAGES

Klise, Katherine A.; Bynum, Michael; Moriarty, Dylan; ...

2017-07-07

Water utilities are vulnerable to a wide variety of human-caused and natural disasters. The Water Network Tool for Resilience (WNTR) is a new open source PythonTM package designed to help water utilities investigate resilience of water distribution systems to hazards and evaluate resilience-enhancing actions. In this paper, the WNTR modeling framework is presented and a case study is described that uses WNTR to simulate the effects of an earthquake on a water distribution system. The case study illustrates that the severity of damage is not only a function of system integrity and earthquake magnitude, but also of the available resourcesmore » and repair strategies used to return the system to normal operating conditions. While earthquakes are particularly concerning since buried water distribution pipelines are highly susceptible to damage, the software framework can be applied to other types of hazards, including power outages and contamination incidents.« less

A software framework for assessing the resilience of drinking water systems to disasters with an example earthquake case study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klise, Katherine A.; Bynum, Michael; Moriarty, Dylan

Water utilities are vulnerable to a wide variety of human-caused and natural disasters. The Water Network Tool for Resilience (WNTR) is a new open source PythonTM package designed to help water utilities investigate resilience of water distribution systems to hazards and evaluate resilience-enhancing actions. In this paper, the WNTR modeling framework is presented and a case study is described that uses WNTR to simulate the effects of an earthquake on a water distribution system. The case study illustrates that the severity of damage is not only a function of system integrity and earthquake magnitude, but also of the available resourcesmore » and repair strategies used to return the system to normal operating conditions. While earthquakes are particularly concerning since buried water distribution pipelines are highly susceptible to damage, the software framework can be applied to other types of hazards, including power outages and contamination incidents.« less

49 CFR 192.3 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... header or manifold. SMYS means specified minimum yield strength is: (1) For steel pipe manufactured in... the waters from the mean high water mark of the coast of the Gulf of Mexico and its inlets open to the... water. High-pressure distribution system means a distribution system in which the gas pressure in the...

49 CFR 192.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... header or manifold. SMYS means specified minimum yield strength is: (1) For steel pipe manufactured in... the waters from the mean high water mark of the coast of the Gulf of Mexico and its inlets open to the... water. High-pressure distribution system means a distribution system in which the gas pressure in the...

49 CFR 192.3 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... header or manifold. SMYS means specified minimum yield strength is: (1) For steel pipe manufactured in... the waters from the mean high water mark of the coast of the Gulf of Mexico and its inlets open to the... water. High-pressure distribution system means a distribution system in which the gas pressure in the...

49 CFR 192.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... header or manifold. SMYS means specified minimum yield strength is: (1) For steel pipe manufactured in... the waters from the mean high water mark of the coast of the Gulf of Mexico and its inlets open to the... water. High-pressure distribution system means a distribution system in which the gas pressure in the...

49 CFR 192.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... header or manifold. SMYS means specified minimum yield strength is: (1) For steel pipe manufactured in... the waters from the mean high water mark of the coast of the Gulf of Mexico and its inlets open to the... water. High-pressure distribution system means a distribution system in which the gas pressure in the...

Controlling Disinfection Residual Losses in Drinking Water Distribution Systems: Results from Experimental Studies

EPA Science Inventory

It is generally accepted that water quality can deteriorate in a distribution system through reactions in the bulk phase and/or at the pipe wall. These reactions may be physical, chemical and/or microbiological in nature. Perhaps one of the most serious aspects of water quality...

Controlling Disinfection Residual Losses in Drinking Water Distribution Systems: Results from Experimental Studies

EPA Science Inventory

It has become generally accepted that water quality can deteriorate in a distribution system through reactions in the bulk phase and/or at the pipe wall. These reactions may be physical, chemical and/or microbiological in nature. Perhaps one of the most serious aspects of water...

A Long-Term Study of the Microbial Community Structure in a Simulated Chloraminated Drinking Water Distribution System

EPA Science Inventory

Free chlorine is used as the primary disinfectant in most drinking water distribution systems(DWDS). However, chlorine disinfection promotes the formation of disinfectant by-products (DBPs)and as a result, many US water treatment facilities use chloramination to ensure regulatory...

DISTRIBUTION SYSTEM: COST OF REPAIR AND REPLACEMENT

EPA Science Inventory

The Safe Drinking Water Act of 1974 mandates that EPA be concerned with the supply of potable water to the consumer. Although most emphasis has been placed on water quality as it leaves the treatment plant interest is increasing in the role of the distribution system in causing w...

THE OCCURRENCE OF CONTAMINANT ACCUMULATION IN LEAD PIPE SCALES FROM DOMESTIC DRINKING WATER DISTRIBUTION SYSTEMS

EPA Science Inventory

Previous work has shown that contaminants, such as Al, As and Ra, can accumulate in drinking water distribution system solids. The release of accumulated contaminants back into the water supply could result in elevated levels at consumers’ taps, and current monitoring practices d...

The Occurrence of Contaminant Accumulation in Lead Pipe Scales from Domestic Drinking Water Distribution Systems-ABSTRACT

EPA Science Inventory

Previous work has shown that contaminants such as Al, As and Ra, can accumulate in drinking water distribution system solids. The release of accumulated contaminants back into the water supply could conceivably result in elevated levels at consumers’ taps. The current regulatory...

Second-Order Chlorine Decay and Trihalomethanes Formation in a Pilot-Scale Water Distribution Systems

EPA Science Inventory

It is well known that model-building of chlorine decay in real water distribution systems is difficult because chlorine decay is influenced by many factors (e.g., bulk water demand, pipe-wall demand, piping material, flow velocity, and residence time). In this paper, experiments ...

Microbial Community Dynamics of a Simulated Chloraminated Drinking Water Distribution System Subjected to Episodes of Nitrification

EPA Science Inventory

Bacterial populations were examined in a simulated chloraminated drinking water distribution system (i.e. loop). The loop (BW-AB-I) received chlorinated municipal water (BW-C) amended with ammonia (2mg/L monochloramine). After six years of continuous operation, the operational ...

Thermal Distribution System | Energy Systems Integration Facility | NREL

Science.gov Websites

Thermal Distribution System Thermal Distribution System The Energy Systems Integration Facility's integrated thermal distribution system consists of a thermal water loop connected to a research boiler and . Photo of the roof of the Energy Systems Integration Facility. The thermal distribution bus allows

DETERMINANTS AND OPTIONS FOR WATER DISTRIBUTION SYSTEM MANAGEMENT: A COST EVALUATION

EPA Science Inventory

This report deals with the problems associated with maintaining and replacing water supply distribution systems. Some of these problems are associated with public health, economic and spatial development of the community, and costs of repair and replacement of system components. ...

Getting the lead out: understanding risks in the distribution system

EPA Science Inventory

This presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation me...

Long-term spatial and temporal microbial community dynamics in a large-scale drinking water distribution system with multiple disinfectant regimes.

PubMed

Potgieter, Sarah; Pinto, Ameet; Sigudu, Makhosazana; du Preez, Hein; Ncube, Esper; Venter, Stephanus

2018-08-01

Long-term spatial-temporal investigations of microbial dynamics in full-scale drinking water distribution systems are scarce. These investigations can reveal the process, infrastructure, and environmental factors that influence the microbial community, offering opportunities to re-think microbial management in drinking water systems. Often, these insights are missed or are unreliable in short-term studies, which are impacted by stochastic variabilities inherent to large full-scale systems. In this two-year study, we investigated the spatial and temporal dynamics of the microbial community in a large, full scale South African drinking water distribution system that uses three successive disinfection strategies (i.e. chlorination, chloramination and hypochlorination). Monthly bulk water samples were collected from the outlet of the treatment plant and from 17 points in the distribution system spanning nearly 150 km and the bacterial community composition was characterised by Illumina MiSeq sequencing of the V4 hypervariable region of the 16S rRNA gene. Like previous studies, Alpha- and Betaproteobacteria dominated the drinking water bacterial communities, with an increase in Betaproteobacteria post-chloramination. In contrast with previous reports, the observed richness, diversity, and evenness of the bacterial communities were higher in the winter months as opposed to the summer months in this study. In addition to temperature effects, the seasonal variations were also likely to be influenced by changes in average water age in the distribution system and corresponding changes in disinfectant residual concentrations. Spatial dynamics of the bacterial communities indicated distance decay, with bacterial communities becoming increasingly dissimilar with increasing distance between sampling locations. These spatial effects dampened the temporal changes in the bulk water community and were the dominant factor when considering the entire distribution system. However, temporal variations were consistently stronger as compared to spatial changes at individual sampling locations and demonstrated seasonality. This study emphasises the need for long-term studies to comprehensively understand the temporal patterns that would otherwise be missed in short-term investigations. Furthermore, systematic long-term investigations are particularly critical towards determining the impact of changes in source water quality, environmental conditions, and process operations on the changes in microbial community composition in the drinking water distribution system. Copyright © 2018 Elsevier Ltd. All rights reserved.

Changes in bacterial composition of biofilm in a metropolitan drinking water distribution system.

PubMed

Revetta, R P; Gomez-Alvarez, V; Gerke, T L; Santo Domingo, J W; Ashbolt, N J

2016-07-01

This study examined the development of bacterial biofilms within a metropolitan distribution system. The distribution system is fed with different source water (i.e. groundwater, GW and surface water, SW) and undergoes different treatment processes in separate facilities. The biofilm community was characterized using 16S rRNA gene clone libraries and functional potential analysis, generated from total DNA extracted from coupons in biofilm annular reactors fed with onsite drinking water for up to 18 months. Differences in the bacterial community structure were observed between GW and SW. Representatives that explained the dissimilarity were associated with the classes Betaproteobacteria, Alphaproteobacteria, Actinobacteria, Gammaproteobacteria and Firmicutes. After 9 months the biofilm bacterial community from both GW and SW were dominated by Mycobacterium species. The distribution of the dominant operational taxonomic unit (OTU) (Mycobacterium) positively correlated with the drinking water distribution system (DWDS) temperature. In this study, the biofilm community structure observed between GW and SW were dissimilar, while communities from different locations receiving SW did not show significant differences. The results suggest that source water and/or the water quality shaped by their respective treatment processes may play an important role in shaping the bacterial communities in the distribution system. In addition, several bacterial groups were present in all samples, suggesting that they are an integral part of the core microbiota of this DWDS. These results provide an ecological insight into biofilm bacterial structure in chlorine-treated drinking water influenced by different water sources and their respective treatment processes. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

A two-stage predictive model to simultaneous control of trihalomethanes in water treatment plants and distribution systems: adaptability to treatment processes.

PubMed

Domínguez-Tello, Antonio; Arias-Borrego, Ana; García-Barrera, Tamara; Gómez-Ariza, José Luis

2017-10-01

The trihalomethanes (TTHMs) and others disinfection by-products (DBPs) are formed in drinking water by the reaction of chlorine with organic precursors contained in the source water, in two consecutive and linked stages, that starts at the treatment plant and continues in second stage along the distribution system (DS) by reaction of residual chlorine with organic precursors not removed. Following this approach, this study aimed at developing a two-stage empirical model for predicting the formation of TTHMs in the water treatment plant and subsequently their evolution along the water distribution system (WDS). The aim of the two-stage model was to improve the predictive capability for a wide range of scenarios of water treatments and distribution systems. The two-stage model was developed using multiple regression analysis from a database (January 2007 to July 2012) using three different treatment processes (conventional and advanced) in the water supply system of Aljaraque area (southwest of Spain). Then, the new model was validated using a recent database from the same water supply system (January 2011 to May 2015). The validation results indicated no significant difference in the predictive and observed values of TTHM (R 2 0.874, analytical variance <17%). The new model was applied to three different supply systems with different treatment processes and different characteristics. Acceptable predictions were obtained in the three distribution systems studied, proving the adaptability of the new model to the boundary conditions. Finally the predictive capability of the new model was compared with 17 other models selected from the literature, showing satisfactory results prediction and excellent adaptability to treatment processes.

Occurrence of contaminant accumulation in lead pipe scales from domestic drinking-water distribution systems.

PubMed

Schock, Michael R; Hyland, Robert N; Welch, Meghan M

2008-06-15

Previously, contaminants, such as AI, As, and Ra, have been shown to accumulate in drinking-water distribution system solids. Accumulated contaminants could be periodically released back into the water supply causing elevated levels at consumers taps, going undetected by most current regulatory monitoring practices and consequently constituting a hidden risk. The objective of this study was to determine the occurrence of over 40 major scale constituents, regulated metals, and other potential metallic inorganic contaminants in drinking-water distribution system Pb (lead) or Pb-lined service lines. The primary method of analysis was inductively coupled plasma-atomic emission spectroscopy, following complete decomposition of scale material. Contaminants and scale constituents were categorized by their average concentrations, and many metals of potential health concern were found to occur at levels sufficient to result in elevated levels at the consumer's taps if they were to be mobilized. The data indicate distinctly nonconservative behavior for many inorganic contaminants in drinking-water distribution systems. This finding suggests an imminent need for further research into the transport and fate of contaminants throughout drinking-water distribution system pipes, as well as a re-evaluation of monitoring protocols in order to more accurately determine the scope and levels of potential consumer exposure.

Implications of biofilm-associated waterborne Cryptosporidium oocysts for the water industry.

PubMed

Angles, Mark L; Chandy, Joseph P; Cox, Peter T; Fisher, Ian H; Warnecke, Malcolm R

2007-08-01

Waterborne Cryptosporidium has been responsible for drinking water-associated disease outbreaks in a number of developed countries. As a result of the resistance of Cryptosporidium to chlorine, which is typically applied as a final barrier to protect the quality of distributed drinking water, current management practices are focused on source-water management and water treatment as ways of preventing Cryptosporidium from entering drinking-water supplies. In the event that treatment barriers fail, surprisingly little is known of the fate of oocysts once they enter a distribution system. To assess properly the risks of waterborne Cryptosporidium, a more thorough understanding of the fate of oocysts in water distribution systems, with emphasis on Cryptosporidium-biofilm interactions, is required.

STANDARDIZED COSTS FOR WATER SUPPLY DISTRIBUTION SYSTEMS

EPA Science Inventory

Presented within the report are cost data for construction and operation/maintenance of domestic water distribution and transmission pipelines, domestic water pumping stations, and domestic water storage reservoirs. To allow comparison of new construction with rehabilitation of e...

A Clonal Lineage of Fusarium oxysporum Circulates in the Tap Water of Different French Hospitals

PubMed Central

Sautour, Marc; Gautheron, Nadine; Laurent, Julie; Aho, Serge; Bonnin, Alain; Sixt, Nathalie; Hartemann, Philippe; Dalle, Frédéric; Steinberg, Christian

2016-01-01

ABSTRACT Fusarium oxysporum is typically a soilborne fungus but can also be found in aquatic environments. In hospitals, water distribution systems may be reservoirs for the fungi responsible for nosocomial infections. F. oxysporum was previously detected in the water distribution systems of five French hospitals. Sixty-eight isolates from water representative of all hospital units that were previously sampled and characterized by translation elongation factor 1α sequence typing were subjected to microsatellite analysis and full-length ribosomal intergenic spacer (IGS) sequence typing. All but three isolates shared common microsatellite loci and a common two-locus sequence type (ST). This ST has an international geographical distribution in both the water networks of hospitals and among clinical isolates. The ST dominant in water was not detected among 300 isolates of F. oxysporum that originated from surrounding soils. Further characterization of 15 isolates by vegetative compatibility testing allowed us to conclude that a clonal lineage of F. oxysporum circulates in the tap water of the different hospitals. IMPORTANCE We demonstrated that a clonal lineage of Fusarium oxysporum inhabits the water distribution systems of several French hospitals. This clonal lineage, which appears to be particularly adapted to water networks, represents a potential risk for human infection and raises questions about its worldwide distribution. PMID:27663024

Condition Assessment of Ferrous Water Transmission and Distribution Systems State of Technology Review Report

EPA Science Inventory

This White Paper was developed to serve as the basis for discussion at a Technology Forum on Condition Assessment of Water Transmission and Distribution Systems that was held on September 9 and 10, 2008, at Edison, NJ. It was distributed to the Forum participants for review in a...

Accumulation and Fate of Microorganisms and Microspheres in Biofilms Formed in a Pilot-Scale Water Distribution System

PubMed Central

Långmark, Jonas; Storey, Michael V.; Ashbolt, Nicholas J.; Stenström, Thor-Axel

2005-01-01

The accumulation and fate of model microbial “pathogens” within a drinking-water distribution system was investigated in naturally grown biofilms formed in a novel pilot-scale water distribution system provided with chlorinated and UV-treated water. Biofilms were exposed to 1-μm hydrophilic and hydrophobic microspheres, Salmonella bacteriophages 28B, and Legionella pneumophila bacteria, and their fate was monitored over a 38-day period. The accumulation of model pathogens was generally independent of the biofilm cell density and was shown to be dependent on particle surface properties, where hydrophilic spheres accumulated to a larger extent than hydrophobic ones. A higher accumulation of culturable legionellae was measured in the chlorinated system compared to the UV-treated system with increasing residence time. The fate of spheres and fluorescence in situ hybridization-positive legionellae was similar and independent of the primary disinfectant applied and water residence time. The more rapid loss of culturable legionellae compared to the fluorescence in situ hybridization-positive legionellae was attributed to a loss in culturability rather than physical desorption. Loss of bacteriophage 28B plaque-forming ability together with erosion may have affected their fate within biofilms in the pilot-scale distribution system. The current study has demonstrated that desorption was one of the primary mechanisms affecting the loss of microspheres, legionellae, and bacteriophage from biofilms within a pilot-scale distribution system as well as disinfection and biological grazing. In general, two primary disinfection regimens (chlorination and UV treatment) were not shown to have a measurable impact on the accumulation and fate of model microbial pathogens within a water distribution system. PMID:15691920

Accumulation and fate of microorganisms and microspheres in biofilms formed in a pilot-scale water distribution system.

PubMed

Långmark, Jonas; Storey, Michael V; Ashbolt, Nicholas J; Stenström, Thor-Axel

2005-02-01

The accumulation and fate of model microbial "pathogens" within a drinking-water distribution system was investigated in naturally grown biofilms formed in a novel pilot-scale water distribution system provided with chlorinated and UV-treated water. Biofilms were exposed to 1-mum hydrophilic and hydrophobic microspheres, Salmonella bacteriophages 28B, and Legionella pneumophila bacteria, and their fate was monitored over a 38-day period. The accumulation of model pathogens was generally independent of the biofilm cell density and was shown to be dependent on particle surface properties, where hydrophilic spheres accumulated to a larger extent than hydrophobic ones. A higher accumulation of culturable legionellae was measured in the chlorinated system compared to the UV-treated system with increasing residence time. The fate of spheres and fluorescence in situ hybridization-positive legionellae was similar and independent of the primary disinfectant applied and water residence time. The more rapid loss of culturable legionellae compared to the fluorescence in situ hybridization-positive legionellae was attributed to a loss in culturability rather than physical desorption. Loss of bacteriophage 28B plaque-forming ability together with erosion may have affected their fate within biofilms in the pilot-scale distribution system. The current study has demonstrated that desorption was one of the primary mechanisms affecting the loss of microspheres, legionellae, and bacteriophage from biofilms within a pilot-scale distribution system as well as disinfection and biological grazing. In general, two primary disinfection regimens (chlorination and UV treatment) were not shown to have a measurable impact on the accumulation and fate of model microbial pathogens within a water distribution system.

Characterization of bacterial coliform occurrences in different zones of a drinking water distribution system.

PubMed

Blanch, A R; Galofré, B; Lucena, F; Terradillos, A; Vilanova, X; Ribas, F

2007-03-01

To compare the bacterial coliforms detected from occurrences in three zones of a water distribution system supplied by two separate water sources. Conventional and standardized protocols for identifying enterobacterial populations were applied. Additional tests to confirm isolates were included. Analyses of diversity and population similarity were performed using the Phene Plate System, a miniaturized biochemical phenotyping method. Isolates were identified by the API 20E system in tandem with biochemical phenotyping. A total of 16 576 samples were taken from the water distribution system, with 1416 isolates analysed. A low number of coliform occurrences were observed (2%). Escherichia coli was not detected in either water origin or in Zone 2 samples; however, in Zones 1 and 3 a low number of cases of E. coli were recorded. The percentages of E. coli depended on the identification criteria. Eight biochemical profiles for coliform populations were defined according to the results of the confirmative tests. There was a high diversity among these populations in the three zones studied, although no significant variations in their composition (associated with occurrences in the different zones) were observed. Klebsiella oxytoca was the most commonly detected species irrespective of zone, although seven other enterobacterial genera were also found. Analysis of the enzymatic activity of beta-glucuronidase or application of the criteria established in the norm ISO 9308-1, in tandem with thermotolerance was needed to evaluate the occurrence of E. coli in the distribution systems. Detected occurrences of bacterial coliforms could be associated with re-growth patterns for specific sampling points in the distribution system. Seasonal differences, independent of the studied zones, were observed. Biochemical phenotyping of bacterial coliforms was shown to be a useful method on the characterization of occurrences in water distribution systems.

Strategies for monitoring the bacteriological quality of water supply in distribution systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geldreich, E.E.; Goodrich, J.A.; Clark, R.M.

1989-01-01

Monitoring strategies for characterizing the bacteriological quality of water in the distribution system require a complete understanding of a variety of interrelated aspects that include treated water quality, water-supply retention in storage and infrastructure deterioration in the distribution system. A study of field data from several water-supply utilities was used to highlight some innovative interpretations of compliance monitoring data. Major perceptions include: The use of a 5% coliform frequency of occurrence limit highlights compliance significance in those situations where there are clusters of positive samples containing less than 4 coliforms per 100 mL. Unfortunately, this presence/absence concept does not providemore » any indication of the magnitude of a contamination event.« less

Detection of underground water distribution piping system and leakages using ground penetrating radar (GPR)

NASA Astrophysics Data System (ADS)

Amran, Tengku Sarah Tengku; Ismail, Mohamad Pauzi; Ahmad, Mohamad Ridzuan; Amin, Mohamad Syafiq Mohd; Sani, Suhairy; Masenwat, Noor Azreen; Ismail, Mohd Azmi; Hamid, Shu-Hazri Abdul

2017-01-01

A water pipe is any pipe or tubes designed to transport and deliver water or treated drinking with appropriate quality, quantity and pressure to consumers. The varieties include large diameter main pipes, which supply entire towns, smaller branch lines that supply a street or group of buildings or small diameter pipes located within individual buildings. This distribution system (underground) is used to describe collectively the facilities used to supply water from its source to the point of usage. Therefore, a leaking in the underground water distribution piping system increases the likelihood of safe water leaving the source or treatment facility becoming contaminated before reaching the consumer. Most importantly, leaking can result in wastage of water which is precious natural resources. Furthermore, they create substantial damage to the transportation system and structure within urban and suburban environments. This paper presents a study on the possibility of using ground penetrating radar (GPR) with frequency of 1GHz to detect pipes and leakages in underground water distribution piping system. Series of laboratory experiment was designed to investigate the capability and efficiency of GPR in detecting underground pipes (metal and PVC) and water leakages. The data was divided into two parts: 1. detecting/locating underground water pipe, 2. detecting leakage of underground water pipe. Despite its simplicity, the attained data is proved to generate a satisfactory result indicating GPR is capable and efficient, in which it is able to detect the underground pipe and presence of leak of the underground pipe.

THE PERSISTENCE OF NONTUBERCULOUS MYCOBACTERIA INI A DRINKING WATER DISTRIBUTION SYSTEM AFTER THE ADDITION OF FILTRATION TREATMENT

EPA Science Inventory

There is evidence that drinking water may be a source of pathogenic nontuberculous mycobacteria (NTM) infections 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 determ...

THE PERSISTENCE OF MYCOBACTERIUM AVIUM IN A DRINKING WATER DISTRIBUTION SYSTEM AFTER THE ADDITION OF FILTRATION TREATMENT

EPA Science Inventory

There is evidence that drinking water may be a source of pathogenic nontuberculous mycobacteria (NTM) infections in humans. One method by which NTM are believed to enter drinking water distribution systems is by their intracellular location within protozoa. Our goal was to determ...

Formation and Release Behavior of Iron Corrosion Products under the Influence of Bacterial Communities in a Simulated Water Distribution System

EPA Science Inventory

Understanding the effects of biofilm on the iron corrosion, iron release and associated corrosion by-products is critical for maintaining the water quality and the integrity of drinking water distribution system (DWDS). In this work, iron corrosion experiments under sterilized a...

RELATIONSHIPS BETWEEN LEVELS OF HETEROTROPHIC BACTERIA AND WATER QUALITY PARAMETERS IN A DRINKING WATER DISTRIBUTION SYSTEM

EPA Science Inventory

Conventional plating methods were used to quantify heterotrophic bacteria from a drinking water distribution system. Three media, plate count agar (PCA), R2A agar and sheep blood agar (TSA-SB) were used to determine heterotrophic plate count (HPC) levels. Grab samples were collec...

Real-time ArcGIS and heterotrophic plate count based chloramine disinfectant control in water distribution system.

PubMed

Bai, Xiaohui; Zhi, Xinghua; Zhu, Huifeng; Meng, Mingqun; Zhang, Mingde

2015-01-01

This study investigates the effect of chloramine residual on bacteria growth and regrowth and the relationship between heterotrophic plate counts (HPCs) and the concentration of chloramine residual in the Shanghai drinking water distribution system (DWDS). In this study, models to control HPCs in the water distribution system and consumer taps are also developed. Real-time ArcGIS was applied to show the distribution and changed results of the chloramine residual concentration in the pipe system by using these models. Residual regression analysis was used to get a reasonable range of the threshold values that allows the chloramine residual to efficiently inhibit bacteria growth in the Shanghai DWDS; the threshold values should be between 0.45 and 0.5 mg/L in pipe water and 0.2 and 0.25 mg/L in tap water. The low residual chloramine value (0.05 mg/L) of the Chinese drinking water quality standard may pose a potential health risk for microorganisms that should be improved. Disinfection by-products (DBPs) were detected, but no health risk was identified.

Moorhead district heating, phase 2

NASA Astrophysics Data System (ADS)

Sundberg, R. E.

1981-01-01

The feasibility of developing a demonstration cogeneration hot water district heating system was studied. The district heating system would use coal and cogenerated heat from the Moorhead power plant to heat the water that would be distributed through underground pipes to customers or their space and domestic water heating needs, serving a substantial portion of the commercial and institutional loads as well as single and multiple family residences near the distribution lines. The technical feasibility effort considered the distribution network, retrofit of the power plant, and conversion of heating systems in customers' buildings to use hot water from the system. The system would be developed over six years. The economic analysis consisted of a market assessment and development of business plans for construction and operation of the system. Rate design methodology, institutional issues, development risk, and the proposal for implementation are discussed.

Evaluating Fluorscence-Based Metrics for Early Detection of ...

EPA Pesticide Factsheets

Summary: This paper discusses the results of an ongoing Water Research Foundation project on developing a fluorescence sensor system for early detection of distribution system nitrification Summary: This paper discusses the results of an ongoing Water Research Foundation project on developing a fluorescence sensor system for early detection of distribution system nitrification

Distilled Water Distribution Systems. Laboratory Design Notes.

ERIC Educational Resources Information Center

Sell, J.C.

Factors concerning water distribution systems, including an evaluation of materials and a recommendation of materials best suited for service in typical facilities are discussed. Several installations are discussed in an effort to bring out typical features in selected applications. The following system types are included--(1) industrial…

43 CFR 2801.9 - When do I need a grant?

Code of Federal Regulations, 2014 CFR

2014-10-01

..., pipelines, tunnels, and other systems which impound, store, transport, or distribute water; (2) Pipelines and other systems for transporting or distributing liquids and gases, other than water and other than... and terminal facilities used in connection with them; (3) Pipelines, slurry and emulsion systems, and...

43 CFR 2801.9 - When do I need a grant?

Code of Federal Regulations, 2012 CFR

2012-10-01

..., pipelines, tunnels, and other systems which impound, store, transport, or distribute water; (2) Pipelines and other systems for transporting or distributing liquids and gases, other than water and other than... and terminal facilities used in connection with them; (3) Pipelines, slurry and emulsion systems, and...

43 CFR 2801.9 - When do I need a grant?

Code of Federal Regulations, 2011 CFR

2011-10-01

..., pipelines, tunnels, and other systems which impound, store, transport, or distribute water; (2) Pipelines and other systems for transporting or distributing liquids and gases, other than water and other than... and terminal facilities used in connection with them; (3) Pipelines, slurry and emulsion systems, and...

43 CFR 2801.9 - When do I need a grant?

Code of Federal Regulations, 2013 CFR

2013-10-01

..., pipelines, tunnels, and other systems which impound, store, transport, or distribute water; (2) Pipelines and other systems for transporting or distributing liquids and gases, other than water and other than... and terminal facilities used in connection with them; (3) Pipelines, slurry and emulsion systems, and...

GPR-Based Water Leak Models in Water Distribution Systems

PubMed Central

Ayala-Cabrera, David; Herrera, Manuel; Izquierdo, Joaquín; Ocaña-Levario, Silvia J.; Pérez-García, Rafael

2013-01-01

This paper addresses the problem of leakage in water distribution systems through the use of ground penetrating radar (GPR) as a nondestructive method. Laboratory tests are performed to extract features of water leakage from the obtained GPR images. Moreover, a test in a real-world urban system under real conditions is performed. Feature extraction is performed by interpreting GPR images with the support of a pre-processing methodology based on an appropriate combination of statistical methods and multi-agent systems. The results of these tests are presented, interpreted, analyzed and discussed in this paper.

Measure Guideline: Transitioning to a Tankless Water Heater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brozyna, K.; Rapport, A.

2012-09-01

This Measure Guideline provides information to help residential builders and retrofitters with the design, specification, selection, implementation, installation, and maintenance issues of transitioning from tank-type water heaters to tankless water heaters. The report compares the differences between tankless and tank-type water heaters, highlighting the energy savings that can be realized by adopting tankless water heaters over tank-type water heaters. Selection criteria and risks discussed include unit sizing and location, water distribution system, plumbing line length and diameter, water quality, electrical backup, and code issues. Cost and performance data are provided for various types of tankless and tank-type water heaters, bothmore » natural gas fired and electric. Also considered are interactions between the tankless water heater and other functional elements of a house, such as cold water supply and low-flow devices. Operating costs and energy use of water distribution systems for single- and two-story houses are provided, along with discussion of the various types of distribution systems that can be used with tankless water heaters. Finally, details to prepare for proper installation of a tankless water heater are described.« less

Detection of Leaks in Water Distribution System using Non-Destructive Techniques

NASA Astrophysics Data System (ADS)

Aslam, H.; Kaur, M.; Sasi, S.; Mortula, Md M.; Yehia, S.; Ali, T.

2018-05-01

Water is scarce and needs to be conserved. A considerable amount of water which flows in the water distribution systems was found to be lost due to pipe leaks. Consequently, innovations in methods of pipe leakage detections for early recognition and repair of these leaks is vital to ensure minimum wastage of water in distribution systems. A major component of detection of pipe leaks is the ability to accurately locate the leak location in pipes through minimum invasion. Therefore, this paper studies the leak detection abilities of the three NDT’s: Ground Penetration Radar (GPR) and spectrometer and aims at determining whether these instruments are effective in identifying the leak. An experimental setup was constructed to simulate the underground conditions of water distribution systems. After analysing the experimental data, it was concluded that both the GPR and the spectrometer were effective in detecting leaks in the pipes. However, the results obtained from the spectrometer were not very differentiating in terms of observing the leaks in comparison to the results obtained from the GPR. In addition to this, it was concluded that both instruments could not be used if the water from the leaks had reached on the surface, resulting in surface ponding.

TESTING AND VERIFICATION OF REAL-TIME WATER QUALITY MONITORING SENSORS IN A DISTRIBUTION SYSTEM AGAINST INTRODUCED CONTAMINATION

EPA Science Inventory

Drinking water distribution systems reach the majority of American homes, business and civic areas, and are therefore an attractive target for terrorist attack via direct contamination, or backflow events. Instrumental monitoring of such systems may be used to signal the prese...

MICROBIOLOGICAL CHARACTERIZATION OF BACTERIA INHABITING A WATER DISTRIBUTION SYSTEM SIMULATOR

EPA Science Inventory

The impact of chlorination and chloramination treatments on heterotrophic bacteria (HB) and ammonia oxidizing bacteria (AOB) inhabiting a water distribution system simulator was investigated. Notable changes in bacterial densities were observed during this monitoring study. For e...

Overview of EPA Research on Drinking Water Distribution System Nitrification

EPA Science Inventory

Results from USEPA research investigating drinking water distribution system nitrification will be presented. The two research areas include: (1) monochloramine disinfection kinetics of Nitrosomonas europaea using Propidium Monoazide Quantitative Real-time PCR (PMA-qPCR) and (2...

WATERBORNE PATHOGEN INVASIONS: A CASE FOR WATER QUALITY PROTECTION IN DISTRIBUTION PROTECTION IN DISTRIBUTION

EPA Science Inventory

No degree of treatment will insure the delivery of a safe water supplyto the consumer's tap when the distribution system is subject to cross-connections water pressure losses, frequent line breaks, open reservoirs and infrastructure deterioration. n one recent U.S. outbreak, wate...

DBP formation in hot and cold water across a simulated distribution system: effect of incubation time, heating time, pH, chlorine dose, and incubation temperature.

PubMed

Liu, Boning; Reckhow, David A

2013-10-15

This paper demonstrates that disinfection byproducts (DBP) concentration profiles in heated water were quite different from the DBP concentrations in the cold tap water. Chloroform concentrations in the heated water remained constant or even decreased slightly with increasing distribution system water age. The amount of dichloroacetic acid (DCAA) was much higher in the heated water than in the cold water; however, the maximum levels in heated water with different distribution system water ages did not differ substantially. The levels of trichloroacetic acid (TCAA) in the heated water were similar to the TCAA levels in the tap water, and a slight reduction was observed after the tap water was heated for 24 h. Regardless of water age, significant reductions of nonregulated DBPs were observed after the tap water was heated for 24 h. For tap water with lower water ages, there were significant increases in dichloroacetonitrile (DCAN), chloropicrin (CP), and 1,1-dichloropropane (1,1-DCP) after a short period of heating. Heating of the tap water with low pH led to a more significant increase of chloroform and a more significant short-term increase of DCAN. High pH accelerated the loss of the nonregulated DBPs in the heated water. The results indicated that as the chlorine doses increased, levels of chloroform and DCAA in the heated water increased significantly. However, for TCAA, the thermally induced increase in concentration was only notable for the chlorinated water with very high chlorine dose. Finally, heating may lead to higher DBP concentrations in chlorinated water with lower distribution system temperatures.

Influence of water quality on nitrifier regrowth in two full-scale drinking water distribution systems.

PubMed

Scott, Daniel B; Van Dyke, Michele I; Anderson, William B; Huck, Peter M

2015-12-01

The potential for regrowth of nitrifying microorganisms was monitored in 2 full-scale chloraminated drinking water distribution systems in Ontario, Canada, over a 9-month period. Quantitative PCR was used to measure amoA genes from ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA), and these values were compared with water quality parameters that can influence nitrifier survival and growth, including total chlorine, ammonia, temperature, pH, and organic carbon. Although there were no severe nitrification episodes, AOB and AOA were frequently detected at low concentrations in samples collected from both distribution systems. A culture-based presence-absence test confirmed the presence of viable nitrifiers. AOB were usually present in similar or greater numbers than AOA in both systems. As well, AOB showed higher regrowth potential compared with AOA in both systems. Statistically significant correlations were measured between several water quality parameters of relevance to nitrification. Total chlorine was negatively correlated with both nitrifiers and heterotrophic plate count (HPC) bacteria, and ammonia levels were positively correlated with nitrifiers. Of particular importance was the strong correlation between HPC and AOB, which reinforced the usefulness of HPC as an operational parameter to measure general microbiological conditions in distribution systems.

Molecular characterization of natural biofilms from household taps with different materials: PVC, stainless steel, and cast iron in drinking water distribution system.

PubMed

Lin, Wenfang; Yu, Zhisheng; Chen, Xi; Liu, Ruyin; Zhang, Hongxun

2013-09-01

Microorganism in drinking water distribution system may colonize in biofilms. Bacterial 16S rRNA gene diversities were analyzed in both water and biofilms grown on taps with three different materials (polyvinyl chloride (PVC), stainless steel, and cast iron) from a local drinking water distribution system. In total, five clone libraries (440 sequences) were obtained. The taxonomic composition of the microbial communities was found to be dominated by members of Proteobacteria (65.9-98.9 %), broadly distributed among the classes Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. Other bacterial groups included Firmicutes, Acidobacteria, Bacteroidetes, Cyanobacteria, and Deinococcus-Thermus. Moreover, a small proportion of unclassified bacteria (3.5-10.6 %) were also found. This investigation revealed that the bacterial communities in biofilms appeared much more diversified than expected and more care should be taken to the taps with high bacterial diversity. Also, regular monitor of outflow water would be useful as potentially pathogenic bacteria were detected. In addition, microbial richness and diversity in taps ranked in the order as: PVC < stainless steel < cast iron. All the results interpreted that PVC would be a potentially suitable material for use as tap component in drinking water distribution system.

Locating illicit connections in storm water sewers using fiber-optic distributed temperature sensing.

PubMed

Hoes, O A C; Schilperoort, R P S; Luxemburg, W M J; Clemens, F H L R; van de Giesen, N C

2009-12-01

A newly developed technique using distributed temperature sensing (DTS) has been developed to find illicit household sewage connections to storm water systems in the Netherlands. DTS allows for the accurate measurement of temperature along a fiber-optic cable, with high spatial (2m) and temporal (30s) resolution. We inserted a fiber-optic cable of 1300m in two storm water drains. At certain locations, significant temperature differences with an intermittent character were measured, indicating inflow of water that was not storm water. In all cases, we found that foul water from households or companies entered the storm water system through an illicit sewage connection. The method of using temperature differences for illicit connection detection in storm water networks is discussed. The technique of using fiber-optic cables for distributed temperature sensing is explained in detail. The DTS method is a reliable, inexpensive and practically feasible method to detect illicit connections to storm water systems, which does not require access to private property.

Interpreting drinking water quality in the distribution system using Dempster-Shafer theory of evidence.

PubMed

Sadiq, Rehan; Rodriguez, Manuel J

2005-04-01

Interpreting water quality data routinely generated for control and monitoring purposes in water distribution systems is a complicated task for utility managers. In fact, data for diverse water quality indicators (physico-chemical and microbiological) are generated at different times and at different locations in the distribution system. To simplify and improve the understanding and the interpretation of water quality, methodologies for aggregation and fusion of data must be developed. In this paper, the Dempster-Shafer theory also called theory of evidence is introduced as a potential methodology for interpreting water quality data. The conceptual basis of this methodology and the process for its implementation are presented by two applications. The first application deals with the interpretation of spatial water quality data fusion, while the second application deals with the development of water quality index based on key monitored indicators. Based on the obtained results, the authors discuss the potential contribution of theory of evidence as a decision-making tool for water quality management.

Whole-Genome Sequences of Four Strains Closely Related to Members of the Mycobacterium chelonae Group, Isolated from Biofilms in a Drinking Water Distribution System Simulator

EPA Science Inventory

We report the draft genome sequences of four Mycobacterium chelonae group strains from biofilms obtained after a ‘chlorine burn’ in a chloraminated drinking water distribution system simulator. These opportunistic pathogens have been detected in drinking and hospital water distr...

NATIONAL WATER INFORMATION SYSTEM OF THE U. S. GEOLOGICAL SURVEY.

USGS Publications Warehouse

Edwards, Melvin D.

1985-01-01

National Water Information System (NWIS) has been designed as an interactive, distributed data system. It will integrate the existing, diverse data-processing systems into a common system. It will also provide easier, more flexible use as well as more convenient access and expanded computing, dissemination, and data-analysis capabilities. The NWIS is being implemented as part of a Distributed Information System (DIS) being developed by the Survey's Water Resources Division. The NWIS will be implemented on each node of the distributed network for the local processing, storage, and dissemination of hydrologic data collected within the node's area of responsibility. The processor at each node will also be used to perform hydrologic modeling, statistical data analysis, text editing, and some administrative work.

Toward more accurate basal boundary conditions: a new 2-D model of distributed and channelised subglacial drainage

NASA Astrophysics Data System (ADS)

Werder, M. A.; Hewitt, I. J.; Schoof, C.; Flowers, G. E.

2012-04-01

Basal boundary conditions are one of the least constrained components of today's ice sheet models. To get at these one needs to know the distributed basal water pressure. We present a new glacier drainage system model to contribute to this missing piece of the puzzle. This two dimensional mathematical/numerical model combines distributed and channelised drainage at the ice-bed interface coupled to a water storage component. Notably the model determines the location of the channels as part of the solution. This is achieved by allowing channels (modelled as R-channels) to form on any of the edges of the unstructured triangular grid used to discretise the model. The distributed system is represented by a water sheet which is a continuum description of a linked-cavity system and exchanges water with the channels along their length. Water storage is parameterised as a function of the subglacial water pressure, which can be interpreted as storage in an englacial aquifer or due to elastic processes. The parabolic equation that determines the water pressure is solved using finite elements, the time evolution of the water sheet thickness and channel diameter are governed by local differential equations that are integrated using explicit methods. To explore the model's properties, we apply it to synthetic ice sheet catchments with areas up to 3000km2. We present steady state drainage system configurations and evaluate their channel-network properties (fractal dimensions, channel spacing). We find that an arborescent channel network forms whose density depends on the water sheet conductivity relative to water input. As a further experiment, we force the model with a seasonally and diurnally varying melt water input to investigate how the modelled drainage system evolves on these time scales: a channelised system grows up glacier as meltwater is delivered to the bed in spring and collapses in autumn. Water pressure is highest just before the formation of channels and then drops. Conversely, the diurnal variations in discharge affect the drainage system morphology only slightly. Instead they lead to large water pressure variations which lag meltwater input and coincide with changes in the volume of stored water. By incorporating an evolving R-channel network within a continuum model of distributed water drainage and storage, this 2-D model succeeds in qualitatively reproducing many of the observed and postulated features of the glacier drainage system.

CHANGES IN BACTERIAL COMPOSITION OF BIOFILM IN A ...

EPA Pesticide Factsheets

This study examined the development of bacterial biofilms within a metropolitan distribution system. The distribution system is fed with different source water (i.e., groundwater, GW and surface water, SW) and undergoes different treatment processes in separate facilities. The biofilm community was characterized using 16S rRNA gene clone libraries and functional potential analysis, generated from total DNA extracted from coupons in biofilm annular reactors fed with onsite drinking water for up to eighteen months. Significant differences in the bacterial community structure were observed between GW and SW. Representatives that explained the dissimilarity between service areas were associated with Betaproteobacteria, Alphaproteobacteria, Actinobacteria, Gammaproteobacteria, and Firmicutes. After nine months the biofilm bacterial community from both areas were dominated by Mycobacterium species. The distribution of the dominant OTU (Mycobacterium) positively correlated with the drinking water distribution system (DWDS) temperature, but no clear relationship was seen with free chlorine residual, pH, turbidity or total organic carbon (TOC). The results suggest that biofilm microbial communities harbor distinct and diverse bacterial communities, and that source water, treatment processes and environmental conditions may play an important role in shaping the bacterial community in the distribution system. On the other hand, several bacterial groups were present i

Distribution System Audits, Leak Detection, and Repair: Kirtland Air Force Base Leak Detection and Repair Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Water Best Management Practice #3 Fact Seet: Outlines how a leak detection and repair program helped Kirtland Air Force Base perform distribution system audits, leak detection, and repair to conserve water site-wide.

Metagenomic Analysis of Water Distribution System Bacterial Communities

EPA Science Inventory

The microbial quality of drinking water is assessed using culture-based methods that are highly selective and that tend to underestimate the densities and diversity of microbial populations inhabiting distribution systems. In order to better understand the effect of different dis...

Overview of Causes and Control of Nitrification in Chloraminated Drinking Water Distribution Systems

EPA Science Inventory

This chapter provides an integrated overview of nitrification causes and control in chloraminated drinking water distribution systems, leading to an in-depth discussion of nitrification microbiology, monitoring, prevention, response, and engineering improvements in subsequent man...

Full Scale Drinking Water System Decontamination at the Water Security Test Bed.

PubMed

Szabo, Jeffrey; Hall, John; Reese, Steve; Goodrich, Jim; Panguluri, Sri; Meiners, Greg; Ernst, Hiba

2018-03-20

The EPA's Water Security Test Bed (WSTB) facility is a full-scale representation of a drinking water distribution system. In collaboration with the Idaho National Laboratory (INL), EPA designed the WSTB facility to support full-scale evaluations of water infrastructure decontamination, real-time sensors, mobile water treatment systems, and decontamination of premise plumbing and appliances. The EPA research focused on decontamination of 1) Bacillus globigii (BG) spores, a non-pathogenic surrogate for Bacillus anthracis and 2) Bakken crude oil. Flushing and chlorination effectively removed most BG spores from the bulk water but BG spores still remained on the pipe wall coupons. Soluble oil components of Bakken crude oil were removed by flushing although oil components persisted in the dishwasher and refrigerator water dispenser. Using this full-scale distribution system allows EPA to 1) test contaminants without any human health or ecological risk and 2) inform water systems on effective methodologies responding to possible contamination incidents.

Towards a cyber-physical era: soft computing framework based multi-sensor array for water quality monitoring

NASA Astrophysics Data System (ADS)

Bhardwaj, Jyotirmoy; Gupta, Karunesh K.; Gupta, Rajiv

2018-02-01

New concepts and techniques are replacing traditional methods of water quality parameter measurement systems. This paper introduces a cyber-physical system (CPS) approach for water quality assessment in a distribution network. Cyber-physical systems with embedded sensors, processors and actuators can be designed to sense and interact with the water environment. The proposed CPS is comprised of sensing framework integrated with five different water quality parameter sensor nodes and soft computing framework for computational modelling. Soft computing framework utilizes the applications of Python for user interface and fuzzy sciences for decision making. Introduction of multiple sensors in a water distribution network generates a huge number of data matrices, which are sometimes highly complex, difficult to understand and convoluted for effective decision making. Therefore, the proposed system framework also intends to simplify the complexity of obtained sensor data matrices and to support decision making for water engineers through a soft computing framework. The target of this proposed research is to provide a simple and efficient method to identify and detect presence of contamination in a water distribution network using applications of CPS.

A Clonal Lineage of Fusarium oxysporum Circulates in the Tap Water of Different French Hospitals.

PubMed

Edel-Hermann, Véronique; Sautour, Marc; Gautheron, Nadine; Laurent, Julie; Aho, Serge; Bonnin, Alain; Sixt, Nathalie; Hartemann, Philippe; Dalle, Frédéric; Steinberg, Christian

2016-11-01

Fusarium oxysporum is typically a soilborne fungus but can also be found in aquatic environments. In hospitals, water distribution systems may be reservoirs for the fungi responsible for nosocomial infections. F. oxysporum was previously detected in the water distribution systems of five French hospitals. Sixty-eight isolates from water representative of all hospital units that were previously sampled and characterized by translation elongation factor 1α sequence typing were subjected to microsatellite analysis and full-length ribosomal intergenic spacer (IGS) sequence typing. All but three isolates shared common microsatellite loci and a common two-locus sequence type (ST). This ST has an international geographical distribution in both the water networks of hospitals and among clinical isolates. The ST dominant in water was not detected among 300 isolates of F. oxysporum that originated from surrounding soils. Further characterization of 15 isolates by vegetative compatibility testing allowed us to conclude that a clonal lineage of F. oxysporum circulates in the tap water of the different hospitals. We demonstrated that a clonal lineage of Fusarium oxysporum inhabits the water distribution systems of several French hospitals. This clonal lineage, which appears to be particularly adapted to water networks, represents a potential risk for human infection and raises questions about its worldwide distribution. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Regrowth of potential opportunistic pathogens and algae in reclaimed-water distribution systems.

PubMed

Jjemba, Patrick K; Weinrich, Lauren A; Cheng, Wei; Giraldo, Eugenio; Lechevallier, Mark W

2010-07-01

A study of the quality of reclaimed water in treated effluent, after storage, and at three points in the distribution system of four plants in California, Florida, Massachusetts, and New York was conducted for 1 year. The plants had different treatment processes (conventional versus membrane bioreactor), production capacities, and methods for storage of the water, and the intended end uses of the water were different. The analysis focused on the occurrence of indicator bacteria (heterotrophic bacteria, coliforms, Escherichia coli, and enterococci) and opportunistic pathogens (Aeromonas spp., enteropathogenic E. coli O157:H7, Legionella spp., Mycobacterium spp., and Pseudomonas spp.), as well as algae. Using immunological methods, E. coli O157:H7 was detected in the effluent of only one system, but it was not detected at the sampling points, suggesting that its survival in the system was poor. Although all of the treatment systems effectively reduced the levels of bacteria in the effluent, bacteria regrew in the reservoir and distribution systems because of the loss of residual disinfectant and high assimilable organic carbon levels. In the systems with open reservoirs, algal growth reduced the water quality by increasing the turbidity and accumulating at the end of the distribution system. Opportunistic pathogens, notably Aeromonas, Legionella, Mycobacterium, and Pseudomonas, occurred more frequently than indicator bacteria (enterococci, coliforms, and E. coli). The Mycobacterium spp. were very diverse and occurred most frequently in membrane bioreactor systems, and Mycobacterium cookii was identified more often than the other species. The public health risk associated with these opportunistic pathogens in reclaimed water is unknown. Collectively, our results show the need to develop best management practices for reclaimed water to control bacterial regrowth and degradation of water before it is utilized at the point of use.

Regrowth of Potential Opportunistic Pathogens and Algae in Reclaimed-Water Distribution Systems ▿

PubMed Central

Jjemba, Patrick K.; Weinrich, Lauren A.; Cheng, Wei; Giraldo, Eugenio; LeChevallier, Mark W.

2010-01-01

A study of the quality of reclaimed water in treated effluent, after storage, and at three points in the distribution system of four plants in California, Florida, Massachusetts, and New York was conducted for 1 year. The plants had different treatment processes (conventional versus membrane bioreactor), production capacities, and methods for storage of the water, and the intended end uses of the water were different. The analysis focused on the occurrence of indicator bacteria (heterotrophic bacteria, coliforms, Escherichia coli, and enterococci) and opportunistic pathogens (Aeromonas spp., enteropathogenic E. coli O157:H7, Legionella spp., Mycobacterium spp., and Pseudomonas spp.), as well as algae. Using immunological methods, E. coli O157:H7 was detected in the effluent of only one system, but it was not detected at the sampling points, suggesting that its survival in the system was poor. Although all of the treatment systems effectively reduced the levels of bacteria in the effluent, bacteria regrew in the reservoir and distribution systems because of the loss of residual disinfectant and high assimilable organic carbon levels. In the systems with open reservoirs, algal growth reduced the water quality by increasing the turbidity and accumulating at the end of the distribution system. Opportunistic pathogens, notably Aeromonas, Legionella, Mycobacterium, and Pseudomonas, occurred more frequently than indicator bacteria (enterococci, coliforms, and E. coli). The Mycobacterium spp. were very diverse and occurred most frequently in membrane bioreactor systems, and Mycobacterium cookii was identified more often than the other species. The public health risk associated with these opportunistic pathogens in reclaimed water is unknown. Collectively, our results show the need to develop best management practices for reclaimed water to control bacterial regrowth and degradation of water before it is utilized at the point of use. PMID:20453149

NEUTRONIC REACTOR SYSTEM

DOEpatents

Treshow, M.

1959-02-10

A reactor system incorporating a reactor of the heterogeneous boiling water type is described. The reactor is comprised essentially of a core submerged adwater in the lower half of a pressure vessel and two distribution rings connected to a source of water are disposed within the pressure vessel above the reactor core, the lower distribution ring being submerged adjacent to the uppcr end of the reactor core and the other distribution ring being located adjacent to the top of the pressure vessel. A feed-water control valve, responsive to the steam demand of the load, is provided in the feedwater line to the distribution rings and regulates the amount of feed water flowing to each distribution ring, the proportion of water flowing to the submerged distribution ring being proportional to the steam demand of the load. This invention provides an automatic means exterior to the reactor to control the reactivity of the reactor over relatively long periods of time without relying upon movement of control rods or of other moving parts within the reactor structure.

URBAN DRINKING WATER DISTRIBUTION SYSTEMS: A U.S. PERSPECTIVE

EPA Science Inventory

This paper will examine several case studies that illustrate the critical role drinking water treatment and distribution systems play in protecting public health. It will also present a case study that documents the dramatic impact that the regulations promulgated under the Safe...

EFFECT OF THE DISTRIBUTION SYSTEM ON DRINKING WATER QUALITY

EPA Science Inventory

The SDWA and its amendments has focused interest on the factors that cause the deterioration of water between the treatment plant and the consumer. The distribution system itself can contribute to this deterioration. Numerous examples of waterborne outbreaks have demonstrated the...

Impact of Arsenic Treatment Techniques on Distribution Water Quality

EPA Science Inventory

This presentation will summarize the results of the distribution water quality studies (arsenic, lead, and copper) of the demonstration program. The impact of the treatment systems by type of system (adsorptive media, coagulation/filtration, ion exchange, etc) will be shown by co...

THE FORMATION OF PB (IV) OXIDES IN CHLORINATED WATER

EPA Science Inventory

The foundation for lead control in drinking water distribution systems is based on Pb(II) chemistry. In recent years, however, Pb(IV) oxides have been identified in distribution systems, suggesting that they may be important relative to predicting and controlling lead concentrat...

Online Toxicity Monitors (OTM) for Distribution System Water Quality Monitoring

EPA Science Inventory

Drinking water distribution systems in the U.S. are vulnerable to episodic contamination events (both unintentional and intentional). The U.S. Environmental Protection Agency (EPA) is conducting research to investigate the use of broad-spectrum online toxicity monitors (OTMs) in ...

21 CFR 1250.82 - Potable water systems.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Potable water systems. 1250.82 Section 1250.82... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.82 Potable water systems. The following conditions must be met by vessel water systems used for the storage and distribution of water which has met...

21 CFR 1250.82 - Potable water systems.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Potable water systems. 1250.82 Section 1250.82... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.82 Potable water systems. The following conditions must be met by vessel water systems used for the storage and distribution of water which has met...

21 CFR 1250.82 - Potable water systems.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Potable water systems. 1250.82 Section 1250.82... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.82 Potable water systems. The following conditions must be met by vessel water systems used for the storage and distribution of water which has met...

21 CFR 1250.82 - Potable water systems.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Potable water systems. 1250.82 Section 1250.82... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.82 Potable water systems. The following conditions must be met by vessel water systems used for the storage and distribution of water which has met...

Monochloramine Cometabolism by Mixed-Culture Nitrifiers ...

EPA Pesticide Factsheets

The current research investigated monochloramine cometabolism by nitrifying mixed cultures grown under drinking water relevant conditions and harvested from sand-packed reactors before conducting suspended growth batch kinetic experiments. Three batch reactors were used in each experiment: (1) a positive control to estimate ammonia kinetic parameters, (2) a negative control to account for abiotic reactions, and (3) a cometabolism reactor to estimate cometabolism kinetic constants. Kinetic parameters were estimated in AQUASIM with a simultaneous fit to all experimental data. Cometabolism kinetics were best described by a first order model. Monochloramine cometabolism kinetics were similar to those of ammonia metabolism, and monochloramine cometabolism was a significant loss mechanism (30% of the observed monochloramine loss). These results demonstrated that monochloramine cometabolism occurred in mixed cultures similar to those found in drinking water distribution systems; thus, cometabolism may be a significant contribution to monochloramine loss during nitrification episodes in drinking water distribution systems. The results demonstrated that monochloramine cometabolism occurred in mixed cultures similar to those found in drinking water distribution systems; thus, cometabolism may be a significant contribution to monochloramine loss during nitrification episodes in drinking water distribution systems.

Prevalence of Legionella spp. in water systems of hospitals and hotels in South Western Greece.

PubMed

Fragou, K; Kokkinos, P; Gogos, C; Alamanos, Y; Vantarakis, A

2012-01-01

The aim of the present study was to determine the prevalence of Legionella spp. in water systems of hospitals and hotels located in South Western Greece, to study the molecular epidemiology of the isolated strains and their possible association with bacterial contamination (total count and Pseudomonas aeruginosa), the water pH, and temperature. A prevalence survey for Legionella spp. by culturing techniques in water distribution systems of eight hospitals and nine hotels occurred in South Western Greece. Water sampling and microbiological analysis were carried out following the ISO methods. Legionella pneumophila was detected in 33% and 36% of the distribution systems of hospitals and hotels, respectively. Our survey results suggest a frequent prevalence of elevated concentrations of Legionella spp. in water systems of hospitals and hotels. Our investigation has confirmed the need to regularly monitor the microbiological condition of water systems in hospitals and hotels.

Characterization of Sphingomonas isolates from Finnish and Swedish drinking water distribution systems.

PubMed

Koskinen, R; Ali-Vehmas, T; Kämpfer, P; Laurikkala, M; Tsitko, I; Kostyal, E; Atroshi, F; Salkinoja-Salonen, M

2000-10-01

Sphingomonas species were commonly isolated from biofilms in drinking water distribution systems in Finland (three water meters) and Sweden (five water taps in different buildings). The Sphingomonas isolates (n = 38) were characterized by chemotaxonomic, physiological and phylogenetic methods. Fifteen isolates were designated to species Sphingomonas aromaticivorans, seven isolates to S. subterranea, two isolates to S. xenophaga and one isolate to S. stygia. Thirteen isolates represented one or more new species of Sphingomonas. Thirty-three isolates out of 38 grew at 5 degrees C on trypticase soy broth agar (TSBA) and may therefore proliferate in the Nordic drinking water pipeline where the temperature typically ranges from 2 to 12 degrees C. Thirty-three isolates out of 38 grew at 37 degrees C on TSBA and 15 isolates also grew on blood agar at 37 degrees C. Considering the potentially pathogenic features of sphingomonas, their presence in drinking water distribution systems may not be desirable.

On-line detection of Escherichia coli intrusion in a pilot-scale drinking water distribution system.

PubMed

Ikonen, Jenni; Pitkänen, Tarja; Kosse, Pascal; Ciszek, Robert; Kolehmainen, Mikko; Miettinen, Ilkka T

2017-08-01

Improvements in microbial drinking water quality monitoring are needed for the better control of drinking water distribution systems and for public health protection. Conventional water quality monitoring programmes are not always able to detect a microbial contamination of drinking water. In the drinking water production chain, in addition to the vulnerability of source waters, the distribution networks are prone to contamination. In this study, a pilot-scale drinking-water distribution network with an on-line monitoring system was utilized for detecting bacterial intrusion. During the experimental Escherichia coli intrusions, the contaminant was measured by applying a set of on-line sensors for electric conductivity (EC), pH, temperature (T), turbidity, UV-absorbance at 254 nm (UVAS SC) and with a device for particle counting. Monitored parameters were compared with the measured E. coli counts using the integral calculations of the detected peaks. EC measurement gave the strongest signal compared with the measured baseline during the E. coli intrusion. Integral calculations showed that the peaks in the EC, pH, T, turbidity and UVAS SC data were detected corresponding to the time predicted. However, the pH and temperature peaks detected were barely above the measured baseline and could easily be mixed with the background noise. The results indicate that on-line monitoring can be utilized for the rapid detection of microbial contaminants in the drinking water distribution system although the peak interpretation has to be performed carefully to avoid being mixed up with normal variations in the measurement data. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hotspots for selected metal elements and microbes accumulation and the corresponding water quality deterioration potential in an unchlorinated drinking water distribution system.

PubMed

Liu, Gang; Tao, Yu; Zhang, Ya; Lut, Maarten; Knibbe, Willem-Jan; van der Wielen, Paul; Liu, Wentso; Medema, Gertjan; van der Meer, Walter

2017-11-01

Biofilm formation, loose deposit accumulation and water quality deterioration in drinking water distribution systems have been widely reported. However, the accumulation and distribution of harbored elements and microbes in the different niches (loose deposits, PVC-U biofilm, and HDPE biofilm) and their corresponding potential contribution to water quality deterioration remain unknown. This precludes an in-depth understanding of water quality deterioration and the development of proactive management strategies. The present study quantitatively evaluated the distribution of elements, ATP, Aeromonas spp., and bacterial communities in distribution pipes (PVC-U, D = 110 mm, loose deposit and biofilm niches) and household connection pipes (HDPE, D = 32 mm, HDPE biofilm niches) at ten locations in an unchlorinated distribution system. The results show that loose deposits in PVC-U pipes, acting as sinks, constitute a hotspot (highest total amount per meter pipe) for elements, ATP, and target bacteria groups (e.g., Aeromonas spp., Mycobacterium spp., and Legionella spp.). When drinking water distribution system niches with harbored elements and microbes become sources in the event of disturbances, the highest quality deterioration potential (QDP) is that of HDPE biofilm; this can be attributed to its high surface-to-volume ratio. 16s rRNA analysis demonstrates that, at the genus level, the bacterial communities in the water, loose deposits, PVC-U biofilm, and HDPE biofilm were dominated, respectively, by Polaromonas spp. (2-23%), Nitrosipra spp. (1-47%), Flavobacterium spp. (1-36%), and Flavobacterium spp. (5-67%). The combined results of elemental composition and bacterial community analyses indicate that different dominant bio-chemical processes might occur within the different niches-for example, iron-arsenic oxidizing in loose deposits, bio-calumniation in PVC-U biofilm, and methane oxidizing in HDPE biofilm. The release of 20% loose deposits, 20% PVC-U biofilm and 10% HDPE biofilm will cause significant changes of water bacterial community. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Estimating the spatial distribution of artificial groundwater recharge using multiple tracers.

PubMed

Moeck, Christian; Radny, Dirk; Auckenthaler, Adrian; Berg, Michael; Hollender, Juliane; Schirmer, Mario

2017-10-01

Stable isotopes of water, organic micropollutants and hydrochemistry data are powerful tools for identifying different water types in areas where knowledge of the spatial distribution of different groundwater is critical for water resource management. An important question is how the assessments change if only one or a subset of these tracers is used. In this study, we estimate spatial artificial infiltration along an infiltration system with stage-discharge relationships and classify different water types based on the mentioned hydrochemistry data for a drinking water production area in Switzerland. Managed aquifer recharge via surface water that feeds into the aquifer creates a hydraulic barrier between contaminated groundwater and drinking water wells. We systematically compare the information from the aforementioned tracers and illustrate differences in distribution and mixing ratios. Despite uncertainties in the mixing ratios, we found that the overall spatial distribution of artificial infiltration is very similar for all the tracers. The highest infiltration occurred in the eastern part of the infiltration system, whereas infiltration in the western part was the lowest. More balanced infiltration within the infiltration system could cause the elevated groundwater mound to be distributed more evenly, preventing the natural inflow of contaminated groundwater. Dedicated to Professor Peter Fritz on the occasion of his 80th birthday.

Modeling complexity in engineered infrastructure system: Water distribution network as an example

NASA Astrophysics Data System (ADS)

Zeng, Fang; Li, Xiang; Li, Ke

2017-02-01

The complex topology and adaptive behavior of infrastructure systems are driven by both self-organization of the demand and rigid engineering solutions. Therefore, engineering complex systems requires a method balancing holism and reductionism. To model the growth of water distribution networks, a complex network model was developed following the combination of local optimization rules and engineering considerations. The demand node generation is dynamic and follows the scaling law of urban growth. The proposed model can generate a water distribution network (WDN) similar to reported real-world WDNs on some structural properties. Comparison with different modeling approaches indicates that a realistic demand node distribution and co-evolvement of demand node and network are important for the simulation of real complex networks. The simulation results indicate that the efficiency of water distribution networks is exponentially affected by the urban growth pattern. On the contrary, the improvement of efficiency by engineering optimization is limited and relatively insignificant. The redundancy and robustness, on another aspect, can be significantly improved through engineering methods.

Decision Support for Renewal of Wastewater Collections and Water Distribution Systems

EPA Science Inventory

The decision of how to accomplish the renewal of existing wastewater collection and water distribution systems involves the evaluation of many criteria and parameters. These criteria must be evaluated thoroughly to determine the best way of rehabilitating or replacing these sys...

CHLORINE DECAY AND BIOFILM STUDIES IN A PILOT SCALE DRINKING WATER DISTRIBUTION DEAD END PIPE SYSTEM

EPA Science Inventory

Chlorine decay experiments using a pilot-scale water distribution dead end pipe system were conducted to define relationships between chlorine decay and environmental factors. These included flow rate, biomass concentration and biofilm density, and initial chlorine concentrations...

DECISION SUPPORT FOR RENEWAL OF WASTEWATER COLLECTIONS AND WATER DISTRIBUTION SYSTEMS

EPA Science Inventory

The decision of how to accomplish the renewal of existing wastewater collection and water distribution systems involves the evaluation of many criteria and parameters. These criteria must be evaluated thoroughly to determine the best way of rehabilitating or replacing these syste...

Monitoring Design for Source Identification in Water Distribution Systems

EPA Science Inventory

The design of sensor networks for the purpose of monitoring for contaminants in water distribution systems is currently an active area of research. Much of the effort has been directed at the contamination detection problem and the expression of public health protection objective...

Using System Dynamic Model and Neural Network Model to Analyse Water Scarcity in Sudan

NASA Astrophysics Data System (ADS)

Li, Y.; Tang, C.; Xu, L.; Ye, S.

2017-07-01

Many parts of the world are facing the problem of Water Scarcity. Analysing Water Scarcity quantitatively is an important step to solve the problem. Water scarcity in a region is gauged by WSI (water scarcity index), which incorporate water supply and water demand. To get the WSI, Neural Network Model and SDM (System Dynamic Model) that depict how environmental and social factors affect water supply and demand are developed to depict how environmental and social factors affect water supply and demand. The uneven distribution of water resource and water demand across a region leads to an uneven distribution of WSI within this region. To predict WSI for the future, logistic model, Grey Prediction, and statistics are applied in predicting variables. Sudan suffers from severe water scarcity problem with WSI of 1 in 2014, water resource unevenly distributed. According to the result of modified model, after the intervention, Sudan’s water situation will become better.

Bacterial communities associated with an occurrence of colored water in an urban drinking water distribution system.

PubMed

Wu, Hui Ting; Mi, Zi Long; Zhang, Jing Xu; Chen, Chao; Xie, Shu Guang

2014-08-01

This study aimed to investigate bacterial community in an urban drinking water distribution system (DWDS) during an occurrence of colored water. Variation in the bacterial community diversity and structure was observed among the different waters, with the predominance of Proteobacteria. While Verrucomicrobia was also a major phylum group in colored water. Limnobacter was the major genus group in colored water, but Undibacterium predominated in normal tap water. The coexistence of Limnobacter as well as Sediminibacterium and Aquabacterium might contribute to the formation of colored water. Copyright © 2014 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Bacterial communities in the collection and chlorinated distribution sections of a drinking water system in Budapest, Hungary.

PubMed

Homonnay, Zalán G; Török, György; Makk, Judit; Brumbauer, Anikó; Major, Eva; Márialigeti, Károly; Tóth, Erika

2014-07-01

Bacterial communities of a bank-filtered drinking water system were investigated by aerobic cultivation and clone library analysis. Moreover, bacterial communities were compared using sequence-aided terminal restriction fragment length polymorphism (T-RFLP) fingerprinting at ten characteristic points located at both the collecting and the distributing part of the water supply system. Chemical characteristics of the samples were similar, except for the presence of chlorine residuals in the distribution system and increased total iron concentration in two of the samples. Assimilable organic carbon (AOC) concentration increased within the collection system, it was reduced by chlorination and it increased again in the distribution system. Neither fecal indicators nor pathogens were detected by standard cultivation techniques. Chlorination reduced bacterial diversity and heterotrophic plate counts. Community structures were found to be significantly different before and after chlorination: the diverse communities in wells and the collection system were dominated by chemolithotrophic (e.g., Gallionella and Nitrospira) and oligocarbophilic-heterotrophic bacteria (e.g., Sphingomonas, Sphingopyxis, and Bradyrhizobium). After chlorination in the distribution system, the most characteristic bacterium was related to the facultative methylotrophic Methylocella spp. Communities changed within the distribution system too, Mycobacterium spp. or Sphingopyxis spp. became predominant in certain samples. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hypothetical Modeling of Redox Conditions Within a Complex Ground-Water Flow Field in a Glacial Setting

USGS Publications Warehouse

Feinstein, Daniel T.; Thomas, Mary Ann

2009-01-01

This report describes a modeling approach for studying how redox conditions evolve under the influence of a complex ground-water flow field. The distribution of redox conditions within a flow system is of interest because of the intrinsic susceptibility of an aquifer to redox-sensitive, naturally occurring contaminants - such as arsenic - as well as anthropogenic contaminants - such as chlorinated solvents. The MODFLOW-MT3D-RT3D suite of code was applied to a glacial valley-fill aquifer to demonstrate a method for testing the interaction of flow patterns, sources of reactive organic carbon, and availability of electron acceptors in controlling redox conditions. Modeling results show how three hypothetical distributions of organic carbon influence the development of redox conditions in a water-supply aquifer. The distribution of strongly reduced water depends on the balance between the rate of redox reactions and the capability of different parts of the flow system to transmit oxygenated water. The method can take account of changes in the flow system induced by pumping that result in a new distribution of reduced water.

Accelerating the Integration of Distributed Water Solutions: A Conceptual Financing Model from the Electricity Sector

NASA Astrophysics Data System (ADS)

Quesnel, Kimberly J.; Ajami, Newsha K.; Wyss, Noemi

2017-11-01

Modern challenges require new approaches to urban water management. One solution in the portfolio of potential strategies is the integration of distributed water infrastructure, practices, and technologies into existing systems. However, many practical barriers have prevented the widespread adoption of these systems in the US. The objective of this paper is to address these challenges by developing a conceptual model encompassing regulatory, financial, and governance components that can be used to incorporate new distributed water solutions into our current network. To construct the model, case studies of successfully implemented distributed electricity systems, specifically energy efficiency and renewable energy technologies, were examined to determine how these solutions have become prominent in recent years and what lessons can be applied to the water sector in a similar pursuit. The proposed model includes four action-oriented elements: catalyzing change, establishing funding sources, using resource pathways, and creating innovative governance structures. As illustrated in the model, the water sector should use suite of coordinated policies to promote change, engage end users through fiscal incentives, and encourage research, development and dissemination of new technologies over time.

Accelerating the Integration of Distributed Water Solutions: A Conceptual Financing Model from the Electricity Sector.

PubMed

Quesnel, Kimberly J; Ajami, Newsha K; Wyss, Noemi

2017-11-01

Modern challenges require new approaches to urban water management. One solution in the portfolio of potential strategies is the integration of distributed water infrastructure, practices, and technologies into existing systems. However, many practical barriers have prevented the widespread adoption of these systems in the US. The objective of this paper is to address these challenges by developing a conceptual model encompassing regulatory, financial, and governance components that can be used to incorporate new distributed water solutions into our current network. To construct the model, case studies of successfully implemented distributed electricity systems, specifically energy efficiency and renewable energy technologies, were examined to determine how these solutions have become prominent in recent years and what lessons can be applied to the water sector in a similar pursuit. The proposed model includes four action-oriented elements: catalyzing change, establishing funding sources, using resource pathways, and creating innovative governance structures. As illustrated in the model, the water sector should use suite of coordinated policies to promote change, engage end users through fiscal incentives, and encourage research, development and dissemination of new technologies over time.

24 CFR 3280.612 - Tests and inspection.

Code of Federal Regulations, 2010 CFR

2010-04-01

... leaks. Then the system shall be unplugged and emptied. The waste piping above the level of the water... water and checking for leaks and retarded flow while they are being emptied. (d) Shower compartments... and inspection. (a) Water system. All water piping in the water distribution system shall be subjected...

Water distribution system and diarrheal disease transmission: a case study in Uzbekistan.

PubMed

Semenza, J C; Roberts, L; Henderson, A; Bogan, J; Rubin, C H

1998-12-01

Deteriorating water treatment facilities and distribution systems pose a significant public health threat, particularly in republics of the former Soviet Union. Interventions to decrease the disease burden associated with these water systems range from upgrading distribution networks to installing reverse osmosis technology. To provide insight into this decision process, we conducted a randomized intervention study to provide epidemiologic data for water policy decisions in Nukus, Uzbekistan, where drinking water quality is suboptimal. We interviewed residents of 240 households, 120 with and 120 without access to municipal piped water. Residents of 62 households without piped water were trained to chlorinate their drinking water at home in a narrow-necked water container with a spout. All study subjects (1583 individuals) were monitored biweekly for self-reported diarrheal illness over a period of 9.5 weeks. The home chlorination intervention group had the lowest diarrheal rate (28.8/1,000 subjects/month) despite lack of access to piped water in their homes. Compared with the two groups that did not receive the intervention this rate was one-sixth that of the group with no piped water (179.2/1,000 subjects/month) and one-third that of the households with piped water (75.5/1,000 subjects/month). More than 30% of the households with piped water lacked detectable levels of chlorine residues in their drinking water, despite two-stage chlorination of the source water, and were at increased risk of diarrhea. Forty-two percent of these municipal users reported that water pressure had been intermittent within the previous two days. The dramatic reduction in diarrheal rates in the home-chlorination intervention group indicates that a large proportion of diarrheal diseases in Nukus are water-borne. The home-chlorination group had less diarrhea than the group with piped water, implicating the distribution system as a source of disease transmission. Taken together, these epidemiologic data would support the hypothesis that diarrhea in the piped water group could be attributed to cross-contamination between the municipal water supply and sewer, due to leaky pipes and lack of water pressure. Relatively inexpensive steps, including chlorination, maintaining water pressure, and properly maintaining the distribution system, rather than reverse osmosis technology, should reduce diarrheal rates.

WATER QUALITY EARLY WARNING SYSTEMS FOR SOURCE WATER AND DISTRIBUTION SYSTEM MONITORING

EPA Science Inventory

A variety of probes for use in continuous monitoring of water quality exist. They range from single parameter chemical/physical probes to comprehensive screening systems based on whole organism responses. Originally developed for monitoring specific characteristics of water qua...

Study of hydraulic power recovery from New Mexico water distribution systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schoenmackers, R.

1984-02-01

The results of a survey of New Mexico water distribution systems suitable for hydroelectric power development are reported. The objectives of the survey were to determine the potential for hydraulic power recovery from existing and planned water systems, to identify potential sites, and to study and recommend promising sites for further development. The survey found eleven sites in New Mexico water distribution systems with a total hydroelectric power potential of 736 kilowatts. Seven of these sites, or 439 kilowatts, could be developed immediately, having everything necessary in place but the turbine generator. These sites are located in the Bonito pipelinemore » near Carrizozo (2 sites), Raton, Ruidoso, Santa Fe, Sugarite, and Taos. If all seven sites were developed, the annual energy production could reach 3,800,000 kilowatt hours.« less

Flood impacts on a water distribution network

NASA Astrophysics Data System (ADS)

Arrighi, Chiara; Tarani, Fabio; Vicario, Enrico; Castelli, Fabio

2017-12-01

Floods cause damage to people, buildings and infrastructures. Water distribution systems are particularly exposed, since water treatment plants are often located next to the rivers. Failure of the system leads to both direct losses, for instance damage to equipment and pipework contamination, and indirect impact, since it may lead to service disruption and thus affect populations far from the event through the functional dependencies of the network. In this work, we present an analysis of direct and indirect damages on a drinking water supply system, considering the hazard of riverine flooding as well as the exposure and vulnerability of active system components. The method is based on interweaving, through a semi-automated GIS procedure, a flood model and an EPANET-based pipe network model with a pressure-driven demand approach, which is needed when modelling water distribution networks in highly off-design conditions. Impact measures are defined and estimated so as to quantify service outage and potential pipe contamination. The method is applied to the water supply system of the city of Florence, Italy, serving approximately 380 000 inhabitants. The evaluation of flood impact on the water distribution network is carried out for different events with assigned recurrence intervals. Vulnerable elements exposed to the flood are identified and analysed in order to estimate their residual functionality and to simulate failure scenarios. Results show that in the worst failure scenario (no residual functionality of the lifting station and a 500-year flood), 420 km of pipework would require disinfection with an estimated cost of EUR 21 million, which is about 0.5 % of the direct flood losses evaluated for buildings and contents. Moreover, if flood impacts on the water distribution network are considered, the population affected by the flood is up to 3 times the population directly flooded.

Modeling and Optimization for Management of Intermittent Water Supply

NASA Astrophysics Data System (ADS)

Lieb, A. M.; Wilkening, J.; Rycroft, C.

2014-12-01

In many urban areas, piped water is supplied only intermittently, as valves direct water to different parts of the water distribution system at different times. The flow is transient, and may transition between free-surface and pressurized, resulting in complex dynamical features with important consequences for water suppliers and users. These consequences include degradation of distribution system components, compromised water quality, and inequitable water availability. The goal of this work is to model the important dynamics and identify operating conditions that mitigate certain negative effects of intermittent water supply. Specifically, we will look at controlling valve parameters occurring as boundary conditions in a network model of transient, transition flow through closed pipes. Gradient-based optimization will be used to find boundary values to minimize pressure gradients and ensure equitable water availability at system endpoints.

Linking Health Concepts in the Assessment and Evaluation of Water Distribution Systems

ERIC Educational Resources Information Center

Karney, Bryan W.; Filion, Yves R.

2005-01-01

The concept of health is not only a specific criterion for evaluation of water quality delivered by a distribution system but also a suitable paradigm for overall functioning of the hydraulic and structural components of the system. This article views health, despite its complexities, as the only criterion with suitable depth and breadth to allow…

Seasonal and spatial variability of nitrosamines and their precursor sources at a large-scale urban drinking water system.

PubMed

Woods, Gwen C; Trenholm, Rebecca A; Hale, Bruce; Campbell, Zeke; Dickenson, Eric R V

2015-07-01

Nitrosamines are considered to pose greater health risks than currently regulated DBPs and are subsequently listed as a priority pollutant by the EPA, with potential for future regulation. Denver Water, as part of the EPA's Unregulated Contaminant Monitoring Rule 2 (UCMR2) monitoring campaign, found detectable levels of N-nitrosodimethylamine (NDMA) at all sites of maximum residency within the distribution system. To better understand the occurrence of nitrosamines and nitrosamine precursors, Denver Water undertook a comprehensive year-long monitoring campaign. Samples were taken every two weeks to monitor for NDMA in the distribution system, and quarterly sampling events further examined 9 nitrosamines and nitrosamine precursors throughout the treatment and distribution systems. NDMA levels within the distribution system were typically low (>1.3 to 7.2 ng/L) with a remote distribution site (frequently >200 h of residency) experiencing the highest concentrations found. Eight other nitrosamines (N-nitrosomethylethylamine, N-nitrosodiethylamine, N-nitroso-di-n-propylamine, N-nitroso-di-n-butylamine, N-nitroso-di-phenylamine, N-nitrosopyrrolidine, N-nitrosopiperidine, N-nitrosomorpholine) were also monitored but none of these 8, or precursors of these 8 [as estimated with formation potential (FP) tests], were detected anywhere in raw, partially-treated or distribution samples. Throughout the year, there was evidence that seasonality may impact NDMA formation, such that lower temperatures (~5-10°C) produced greater NDMA than during warmer months. The year of sampling further provided evidence that water quality and weather events may impact NDMA precursor loads. Precursor loading estimates demonstrated that NDMA precursors increased during treatment (potentially from cationic polymer coagulant aids). The precursor analysis also provided evidence that precursors may have increased further within the distribution system itself. This comprehensive study of a large-scale drinking water system provides insight into the variability of NDMA occurrence in a chloraminated system, which may be impacted by seasonality, water quality changes and/or the varied origins of NDMA precursors within a given system. Copyright © 2015 Elsevier B.V. All rights reserved.

Space Station environmental control and life support system distribution and loop closure studies

NASA Technical Reports Server (NTRS)

Humphries, William R.; Reuter, James L.; Schunk, Richard G.

1986-01-01

The NASA Space Station's environmental control and life support system (ECLSS) encompasses functional elements concerned with temperature and humidity control, atmosphere control and supply, atmosphere revitalization, fire detection and suppression, water recovery and management, waste management, and EVA support. Attention is presently given to functional and physical module distributions of the ECLSS among these elements, with a view to resource requirements and safety implications. A strategy of physical distribution coupled with functional centralization is for the air revitalization and water reclamation systems. Also discussed is the degree of loop closure desirable in the initial operational capability status Space Station's oxygen and water reclamation loops.

Real-time determination of the efficacy of residual disinfection to limit wastewater contamination in a water distribution system using filtration-based luminescence.

PubMed

Lee, Jiyoung; Deininger, Rolf A

2010-05-01

Water distribution systems can be vulnerable to microbial contamination through cross-connections, wastewater backflow, the intrusion of soiled water after a loss of pressure resulting from an electricity blackout, natural disaster, or intentional contamination of the system in a bioterrrorism event. The most urgent matter a water treatment utility would face in this situation is detecting the presence and extent of a contamination event in real-time, so that immediate action can be taken to mitigate the problem. The current approved microbiological detection methods are culture-based plate count methods, which require incubation time (1 to 7 days). This long period of time would not be useful for the protection of public health. This study was designed to simulate wastewater intrusion in a water distribution system. The objectives were 2-fold: (1) real-time detection of water contamination, and (2) investigation of the sustainability of drinking water systems to suppress the contamination with secondary disinfectant residuals (chlorine and chloramine). The events of drinking water contamination resulting from a wastewater addition were determined by filtration-based luminescence assay. The water contamination was detected by luminescence method within 5 minutes. The signal amplification attributed to wastewater contamination was clear-102-fold signal increase. After 1 hour, chlorinated water could inactivate 98.8% of the bacterial contaminant, while chloraminated water reduced 77.2%.

Vertical counterflow evaporative cooler

DOEpatents

Bourne, Richard C.; Lee, Brian Eric; Callaway, Duncan

2005-01-25

An evaporative heat exchanger having parallel plates that define alternating dry and wet passages. A water reservoir is located below the plates and is connected to a water distribution system. Water from the water distribution system flows through the wet passages and wets the surfaces of the plates that form the wet passages. Air flows through the dry passages, mixes with air below the plates, and flows into the wet passages before exiting through the top of the wet passages.

Molecular diversity of drinking water bacterial communities using 16S rRNA gene sequence analyses

EPA Science Inventory

Our understanding of the microbial community structure of drinking water distribution system has relied on culture-based methods. However, recent studies have suggested that the majority of bacteria inhabiting distribution systems are unable to grow on artificial media. The goal ...

WATER QUALITY MODELING AND SAMPLING STUDY IN A DISTRIBUTION SYSTEM

EPA Science Inventory

A variety of computer based models have been developed and used by the water industry to access the movement and fate of contaminants within the distribution system. uch models include: ynamic and steady state hydraulic models which simulate the flow quantity, flow direction, and...

Draft Genome Sequences of Six Mycobacterium immunogenum, Strains Obtained from a Chloraminated Drinking Water Distribution System Simulator

EPA Science Inventory

We report the draft genome sequences of six Mycobacterium immunogenum isolated from a chloraminated drinking water distribution system simulator subjected to changes in operational parameters. M. immunogenum, a rapidly growing mycobacteria previously reported as the cause of hyp...

Impact of particles on sediment accumulation in a drinking water distribution system.

PubMed

Vreeburg, J H G; Schippers, D; Verberk, J Q J C; van Dijk, J C

2008-10-01

Discolouration of drinking water is one of the main reasons customers complain to their water company. Though corrosion of cast iron is often seen as the main source for this problem, the particles originating from the treatment plant play an important and potentially dominant role in the generation of a discolouration risk in drinking water distribution systems. To investigate this thesis a study was performed in a drinking water distribution system. In two similar isolated network areas the effect of particles on discolouration risk was studied with particle counting, the Resuspension Potential Method (RPM) and assessment of the total accumulated sediment. In the 'Control Area', supplied with normal drinking water, the discolouration risk was regenerated within 1.5 year. In the 'Research Area', supplied with particle-free water, this will take 10-15 years. An obvious remedy for controlling the discolouration risk is to improve the treatment with respect to the short peaks that are caused by particle breakthrough.

Site 300 City Water Master Plan

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shaw, Jeff

Lawrence Livermore National Laboratory (LLNL), a scientific research facility, operates an experimental test site known as Site 300. The site is located in a remote area of southeastern Alameda County, California, and consists of about 100 facilities spread across 7,000-acres. The Site 300 water system includes groundwater wells and a system of storage tanks, booster pumps, and underground piping to distribute water to buildings and significant areas throughout the site. Site 300, which is classified as a non-transient non-community (NTNC) water system, serves approximately 110 employees through 109 service connections. The distribution system includes approximately 76,500-feet of water mains varyingmore » from 4- to 10-inches in diameter, mostly asbestos cement (AC) pipe, and eleven water storage tanks. The water system is divided into four pressure zones fed by three booster pump stations to tanks in each zone.« less

Plan for the design, development, and implementation, and operation of the National Water Information System

USGS Publications Warehouse

Edwards, M.D.

1987-01-01

The Water Resources Division of the U.S. Geological Survey is developing a National Water Information System (NWIS) that will integrate and replace its existing water data and information systems of the National Water Data Storage and Retrieval System, National Water Data Exchange, National Water-Use Information, and Water Resources Scientific Information Center programs. It will be a distributed data system operated as part of the Division 's Distributed Information System, which is a network of computers linked together through a national telecommunication network known as GEONET. The NWIS is being developed as a series of prototypes that will be integrated as they are completed to allow the development and implementation of the system in a phased manner. It also is being developed in a distributed manner using personnel who work under the coordination of a central NWIS Project Office. Work on the development of the NWIS began in 1983 and it is scheduled for completion in 1990. This document presents an overall plan for the design, development, implementation, and operation of the system. Detailed discussions are presented on each of these phases of the NWIS life cycle. The planning, quality assurance, and configuration management phases of the life cycle also are discussed. The plan is intended to be a working document for use by NWIS management and participants in its design and development and to assist offices of the Division in planning and preparing for installation and operation of the system. (Author 's abstract)

The First Association of a Primary Amebic Meningoencephalitis Death with Culturable Naegleria fowleri in Tap Water from a U.S. Treated Public Drinking Water System

PubMed Central

Cope, Jennifer R.; Ratard, Raoult C.; Hill, Vincent R.; Sokol, Theresa; Causey, Jonathan Jake; Yoder, Jonathan S.; Mirani, Gayatri; Mull, Bonnie; Mukerjee, Kimberly A.; Narayanan, Jothikumar; Doucet, Meggie; Qvarnstrom, Yvonne; Poole, Charla N.; Akingbola, Olugbenga A.; Ritter, Jana; Xiong, Zhenggang; da Silva, Alexandre; Roellig, Dawn; Van Dyke, Russell; Stern, Harlan; Xiao, Lihua; Beach, Michael J.

2015-01-01

Background Naegleria fowleri is a climate-sensitive, thermophilic ameba found in warm, freshwater lakes and rivers. Primary amebic meningoencephalitis (PAM), which is almost universally fatal, occurs when N. fowleri–containing water enters the nose, typically during swimming, and N. fowleri migrates to the brain via the olfactory nerve. In August 2013, a 4-year-old child died of meningoencephalitis of unknown etiology in a Louisiana hospital. Methods Clinical and environmental testing and a case investigation were initiated to determine the cause of death and to identify potential exposures. Results Based on testing of CSF and brain specimens, the child was diagnosed with PAM. His only reported water exposure was tap water; in particular, tap water that was used to supply water to a lawn water slide on which the child had played extensively prior to becoming ill. Water samples were collected from both the home and the water distribution system that supplied the home and tested; N. fowleri were identified in water samples from both the home and the water distribution system. Conclusions This case is the first reported PAM death associated with culturable N. fowleri in tap water from a U.S. treated drinking water system. This case occurred in the context of an expanding geographic range for PAM beyond southern tier states with recent case reports from Minnesota, Kansas, and Indiana. This case also highlights the role of adequate disinfection throughout drinking water distribution systems and the importance of maintaining vigilance when operating drinking water systems using source waters with elevated temperatures. PMID:25595746

The first association of a primary amebic meningoencephalitis death with culturable Naegleria fowleri in tap water from a US treated public drinking water system.

PubMed

Cope, Jennifer R; Ratard, Raoult C; Hill, Vincent R; Sokol, Theresa; Causey, Jonathan Jake; Yoder, Jonathan S; Mirani, Gayatri; Mull, Bonnie; Mukerjee, Kimberly A; Narayanan, Jothikumar; Doucet, Meggie; Qvarnstrom, Yvonne; Poole, Charla N; Akingbola, Olugbenga A; Ritter, Jana M; Xiong, Zhenggang; da Silva, Alexandre J; Roellig, Dawn; Van Dyke, Russell B; Stern, Harlan; Xiao, Lihua; Beach, Michael J

2015-04-15

Naegleria fowleri is a climate-sensitive, thermophilic ameba found in warm, freshwater lakes and rivers. Primary amebic meningoencephalitis (PAM), which is almost universally fatal, occurs when N. fowleri-containing water enters the nose, typically during swimming, and migrates to the brain via the olfactory nerve. In August 2013, a 4-year-old boy died of meningoencephalitis of unknown etiology in a Louisiana hospital. Clinical and environmental testing and a case investigation were initiated to determine the cause of death and to identify potential exposures. Based on testing of cerebrospinal fluid and brain specimens, the child was diagnosed with PAM. His only reported water exposure was tap water; in particular, tap water that was used to supply water to a lawn water slide on which the child had played extensively prior to becoming ill. Water samples were collected from both the home and the water distribution system that supplied the home and tested; N. fowleri was identified in water samples from both the home and the water distribution system. This case is the first reported PAM death associated with culturable N. fowleri in tap water from a US treated drinking water system. This case occurred in the context of an expanding geographic range for PAM beyond southern states, with recent case reports from Minnesota, Kansas, and Indiana. This case also highlights the role of adequate disinfection throughout drinking water distribution systems and the importance of maintaining vigilance when operating drinking water systems using source waters with elevated temperatures. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Open Data, Open Specifications and Free and Open Source Software: A powerful mix to create distributed Web-based water information systems

NASA Astrophysics Data System (ADS)

Arias, Carolina; Brovelli, Maria Antonia; Moreno, Rafael

2015-04-01

We are in an age when water resources are increasingly scarce and the impacts of human activities on them are ubiquitous. These problems don't respect administrative or political boundaries and they must be addressed integrating information from multiple sources at multiple spatial and temporal scales. Communication, coordination and data sharing are critical for addressing the water conservation and management issues of the 21st century. However, different countries, provinces, local authorities and agencies dealing with water resources have diverse organizational, socio-cultural, economic, environmental and information technology (IT) contexts that raise challenges to the creation of information systems capable of integrating and distributing information across their areas of responsibility in an efficient and timely manner. Tight and disparate financial resources, and dissimilar IT infrastructures (data, hardware, software and personnel expertise) further complicate the creation of these systems. There is a pressing need for distributed interoperable water information systems that are user friendly, easily accessible and capable of managing and sharing large volumes of spatial and non-spatial data. In a distributed system, data and processes are created and maintained in different locations each with competitive advantages to carry out specific activities. Open Data (data that can be freely distributed) is available in the water domain, and it should be further promoted across countries and organizations. Compliance with Open Specifications for data collection, storage and distribution is the first step toward the creation of systems that are capable of interacting and exchanging data in a seamlessly (interoperable) way. The features of Free and Open Source Software (FOSS) offer low access cost that facilitate scalability and long-term viability of information systems. The World Wide Web (the Web) will be the platform of choice to deploy and access these systems. Geospatial capabilities for mapping, visualization, and spatial analysis will be important components of these new generation of Web-based interoperable information systems in the water domain. The purpose of this presentation is to increase the awareness of scientists, IT personnel and agency managers about the advantages offered by the combined use of Open Data, Open Specifications for geospatial and water-related data collection, storage and sharing, as well as mature FOSS projects for the creation of interoperable Web-based information systems in the water domain. A case study is used to illustrate how these principles and technologies can be integrated to create a system with the previously mentioned characteristics for managing and responding to flood events.

Potential impacts of changing supply-water quality on drinking water distribution: A review.

PubMed

Liu, Gang; Zhang, Ya; Knibbe, Willem-Jan; Feng, Cuijie; Liu, Wentso; Medema, Gertjan; van der Meer, Walter

2017-06-01

Driven by the development of water purification technologies and water quality regulations, the use of better source water and/or upgraded water treatment processes to improve drinking water quality have become common practices worldwide. However, even though these elements lead to improved water quality, the water quality may be impacted during its distribution through piped networks due to the processes such as pipe material release, biofilm formation and detachment, accumulation and resuspension of loose deposits. Irregular changes in supply-water quality may cause physiochemical and microbiological de-stabilization of pipe material, biofilms and loose deposits in the distribution system that have been established over decades and may harbor components that cause health or esthetical issues (brown water). Even though it is clearly relevant to customers' health (e.g., recent Flint water crisis), until now, switching of supply-water quality is done without any systematic evaluation. This article reviews the contaminants that develop in the water distribution system and their characteristics, as well as the possible transition effects during the switching of treated water quality by destabilization and the release of pipe material and contaminants into the water and the subsequent risks. At the end of this article, a framework is proposed for the evaluation of potential transition effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Searching for storm water inflows in foul sewers using fibre-optic distributed temperature sensing.

PubMed

Schilperoort, Rémy; Hoppe, Holger; de Haan, Cornelis; Langeveld, Jeroen

2013-01-01

A major drawback of separate sewer systems is the occurrence of illicit connections: unintended sewer cross-connections that connect foul water outlets from residential or industrial premises to the storm water system and/or storm water outlets to the foul sewer system. The amount of unwanted storm water in foul sewer systems can be significant, resulting in a number of detrimental effects on the performance of the wastewater system. Efficient removal of storm water inflows into foul sewers requires knowledge of the exact locations of the inflows. This paper presents the use of distributed temperature sensing (DTS) monitoring data to localize illicit storm water inflows into foul sewer systems. Data results from two monitoring campaigns in foul sewer systems in the Netherlands and Germany are presented. For both areas a number of storm water inflow locations can be derived from the data. Storm water inflow can only be detected as long as the temperature of this inflow differs from the in-sewer temperatures prior to the event. Also, the in-sewer propagation of storm and wastewater can be monitored, enabling a detailed view on advection.

Modeling of subglacial hydrological development following rapid supraglacial lake drainage.

PubMed

Dow, C F; Kulessa, B; Rutt, I C; Tsai, V C; Pimentel, S; Doyle, S H; van As, D; Lindbäck, K; Pettersson, R; Jones, G A; Hubbard, A

2015-06-01

The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and examine whether substantial, efficient subglacial channels can form during or following lake drainage events and their effect on the water pressure in the surrounding distributed system. We force the model with field data from a lake drainage site, 70 km from the terminus of Russell Glacier in West Greenland. The model outputs suggest that efficient subglacial channels do not readily form in the vicinity of the lake during rapid drainage and instead water is evacuated primarily by a transient turbulent sheet and the distributed system. Following lake drainage, channels grow but are not large enough to reduce the water pressure in the surrounding distributed system, unless preexisting channels are present throughout the domain. Our results have implications for the analysis of subglacial hydrological systems in regions where rapid lake drainage provides the primary mechanism for surface-to-bed connections. Model for subglacial hydrological analysis of rapid lake drainage eventsLimited subglacial channel growth during and following rapid lake drainagePersistence of distributed drainage in inland areas where channel growth is limited.

Modeling of subglacial hydrological development following rapid supraglacial lake drainage

PubMed Central

Dow, C F; Kulessa, B; Rutt, I C; Tsai, V C; Pimentel, S; Doyle, S H; van As, D; Lindbäck, K; Pettersson, R; Jones, G A; Hubbard, A

2015-01-01

The rapid drainage of supraglacial lakes injects substantial volumes of water to the bed of the Greenland ice sheet over short timescales. The effect of these water pulses on the development of basal hydrological systems is largely unknown. To address this, we develop a lake drainage model incorporating both (1) a subglacial radial flux element driven by elastic hydraulic jacking and (2) downstream drainage through a linked channelized and distributed system. Here we present the model and examine whether substantial, efficient subglacial channels can form during or following lake drainage events and their effect on the water pressure in the surrounding distributed system. We force the model with field data from a lake drainage site, 70 km from the terminus of Russell Glacier in West Greenland. The model outputs suggest that efficient subglacial channels do not readily form in the vicinity of the lake during rapid drainage and instead water is evacuated primarily by a transient turbulent sheet and the distributed system. Following lake drainage, channels grow but are not large enough to reduce the water pressure in the surrounding distributed system, unless preexisting channels are present throughout the domain. Our results have implications for the analysis of subglacial hydrological systems in regions where rapid lake drainage provides the primary mechanism for surface-to-bed connections. Key Points Model for subglacial hydrological analysis of rapid lake drainage events Limited subglacial channel growth during and following rapid lake drainage Persistence of distributed drainage in inland areas where channel growth is limited PMID:26640746

Mixing at double-Tee junctions with unequal pipe sizes in water distribution systems

EPA Science Inventory

Pipe flow mixing with various solute concentrations and flow rates at pipe junctions is investigated. The degree of mixing affects the spread of contaminants in a water distribution system. Many studies have been conducted on the mixing at the cross junctions. Yet a few have focu...

PREDICTING LEAD DISSOLUTION IN DRINKING WATER DISTRIBUTION SYSTEMS: EFFECT OF FLUORIDE ADDITIVES ON LEAD SOLUBILITY AND CORROSION

EPA Science Inventory

Many water systems have encountered difficulties in meeting the action levels established by the Lead and Copper Rule. Several chemical parameters contribute to the corrosion of lead plumbing and may influence the nature of the passivating films formed on distribution materials....

Rehabilitation of Wastewater Collection and Water Distribution Systems -State of Technology Review Report

EPA Science Inventory

This White Paper is intended to provide an overview of the current state-of-the-practice and current state-of-the-art for rehabilitation of pipes and structures within the wastewater collection and water distribution systems. Rehabilitation is defined as repair, renewal, and rep...

Bacterial Composition of Biofilms Collected From Two Service Areas in a Metropolitan Drinking Water Distribution System

EPA Science Inventory

The development and succession of bacteria were examined by 16S rRNA gene clone libraries generated from various biofilms within a metropolitan water distribution system. Biofilms were obtained from off-line devices using polycarbonate coupons from annular reactors incubated for ...

A large waterborne outbreak of campylobacteriosis in Norway: the need to focus on distribution system safety.

PubMed

Jakopanec, Irena; Borgen, Katrine; Vold, Line; Lund, Helge; Forseth, Tore; Hannula, Raisa; Nygård, Karin

2008-09-24

On 7 May 2007 the medical officer in Røros (population 5600) reported 15 patients with gastroenteritis. Three days later he estimated hundreds being ill. Untreated tap water from a groundwater source was suspected as the vehicle and chlorination was started 11 May. Campylobacter was isolated from patients' stool samples. We conducted an investigation to identify the source and describe the extent of the outbreak. We undertook a retrospective cohort study among a random sample of customers of Røros and neighbouring Holtålen waterworks. Holtålen, which has a different water source, was used as a control city. We conducted telephone interviews to gather data on illness from all household members. One randomly selected household member was asked about detailed exposure history. The regional hospital laboratory tested patients' stools for enteropathogens. Campylobacter isolates were typed by AFLP for genetic similarity at the Norwegian Institute of Public Health. Local authorities conducted the environmental investigation. We identified 105 cases among 340 individuals from Røros and Holtålen (Attack Rate = 31%). Tap water consumption was the only exposure associated with illness. Among randomly selected household members from Røros, a dose-response relationship was observed in daily consumed glasses of tap water (chi2 for trend = 8.1, p = 0.004). Campylobacter with identical AFLP was isolated from 25 out of 26 submitted stool samples. No pathogens were detected in water samples. We identified several events that might have caused pressure fall and influx of contaminated water into the water distribution system. On two occasions, pressure fall was noticed and parts of the distribution system were outdated. The investigation confirmed a waterborne outbreak of campylobacteriosis in Røros. Although no single event was identified as the cause of contamination, this outbreak illustrates the vulnerability of water distribution systems. Good quality source water alone is not enough to ensure water safety. For a better risk management, more focus should be put on the distribution system security. Waterworks personnel should monitor the pressure regularly; reduce the leakage by upgrading the distribution network and use chlorination when conducting maintenance work.

A large waterborne outbreak of campylobacteriosis in Norway: The need to focus on distribution system safety

PubMed Central

Jakopanec, Irena; Borgen, Katrine; Vold, Line; Lund, Helge; Forseth, Tore; Hannula, Raisa; Nygård, Karin

2008-01-01

Background On 7 May 2007 the medical officer in Røros (population 5600) reported 15 patients with gastroenteritis. Three days later he estimated hundreds being ill. Untreated tap water from a groundwater source was suspected as the vehicle and chlorination was started 11 May. Campylobacter was isolated from patients' stool samples. We conducted an investigation to identify the source and describe the extent of the outbreak. Methods We undertook a retrospective cohort study among a random sample of customers of Røros and neighbouring Holtålen waterworks. Holtålen, which has a different water source, was used as a control city. We conducted telephone interviews to gather data on illness from all household members. One randomly selected household member was asked about detailed exposure history. The regional hospital laboratory tested patients' stools for enteropathogens. Campylobacter isolates were typed by AFLP for genetic similarity at the Norwegian Institute of Public Health. Local authorities conducted the environmental investigation. Results We identified 105 cases among 340 individuals from Røros and Holtålen (Attack Rate = 31%). Tap water consumption was the only exposure associated with illness. Among randomly selected household members from Røros, a dose-response relationship was observed in daily consumed glasses of tap water (χ2 for trend = 8.1, p = 0.004). Campylobacter with identical AFLP was isolated from 25 out of 26 submitted stool samples. No pathogens were detected in water samples. We identified several events that might have caused pressure fall and influx of contaminated water into the water distribution system. On two occasions, pressure fall was noticed and parts of the distribution system were outdated. Conclusion The investigation confirmed a waterborne outbreak of campylobacteriosis in Røros. Although no single event was identified as the cause of contamination, this outbreak illustrates the vulnerability of water distribution systems. Good quality source water alone is not enough to ensure water safety. For a better risk management, more focus should be put on the distribution system security. Waterworks personnel should monitor the pressure regularly; reduce the leakage by upgrading the distribution network and use chlorination when conducting maintenance work. PMID:18816387

Testing large volume water treatment and crude oil ...

EPA Pesticide Factsheets

Report EPA’s Homeland Security Research Program (HSRP) partnered with the Idaho National Laboratory (INL) to build the Water Security Test Bed (WSTB) at the INL test site outside of Idaho Falls, Idaho. The WSTB was built using an 8-inch (20 cm) diameter cement-mortar lined drinking water pipe that was previously taken out of service. The pipe was exhumed from the INL grounds and oriented in the shape of a small drinking water distribution system. Effluent from the pipe is captured in a lagoon. The WSTB can support drinking water distribution system research on a variety of drinking water treatment topics including biofilms, water quality, sensors, and homeland security related contaminants. Because the WSTB is constructed of real drinking water distribution system pipes, research can be conducted under conditions similar to those in a real drinking water system. In 2014, WSTB pipe was experimentally contaminated with Bacillus globigii spores, a non-pathogenic surrogate for the pathogenic B. anthracis, and then decontaminated using chlorine dioxide. In 2015, the WSTB was used to perform the following experiments: • Four mobile disinfection technologies were tested for their ability to disinfect large volumes of biologically contaminated “dirty” water from the WSTB. B. globigii spores acted as the biological contaminant. The four technologies evaluated included: (1) Hayward Saline C™ 6.0 Chlorination System, (2) Advanced Oxidation Process (A

Artificial sweetener sucralose in U.S. drinking water systems.

PubMed

Mawhinney, Douglas B; Young, Robert B; Vanderford, Brett J; Borch, Thomas; Snyder, Shane A

2011-10-15

The artificial sweetener sucralose has recently been shown to be a widespread of contaminant of wastewater, surface water, and groundwater. In order to understand its occurrence in drinking water systems, water samples from 19 United States (U.S.) drinking water treatment plants (DWTPs) serving more than 28 million people were analyzed for sucralose using liquid chromatography tandem mass spectrometry (LC-MS/MS). Sucralose was found to be present in source water of 15 out of 19 DWTPs (47-2900 ng/L), finished water of 13 out of 17 DWTPs (49-2400 ng/L) and distribution system water of 8 out of the 12 DWTPs (48-2400 ng/L) tested. Sucralose was only found to be present in source waters with known wastewater influence and/or recreational usage, and displayed low removal (12% average) in the DWTPs where finished water was sampled. Further, in the subset of DWTPs with distribution system water sampled, the compound was found to persist regardless of the presence of residual chlorine or chloramines. In order to understand intra-DWTP consistency, sucralose was monitored at one drinking water treatment plant over an 11 month period from March 2010 through January 2011, and averaged 440 ng/L in the source water and 350 ng/L in the finished water. The results of this study confirm that sucralose will function well as an indicator compound for anthropogenic influence on source, finished drinking and distribution system (i.e., tap) water, as well as an indicator compound for the presence of other recalcitrant compounds in finished drinking water in the U.S.

Radial transport processes as a precursor to particle deposition in drinking water distribution systems.

PubMed

van Thienen, P; Vreeburg, J H G; Blokker, E J M

2011-02-01

Various particle transport mechanisms play a role in the build-up of discoloration potential in drinking water distribution networks. In order to enhance our understanding of and ability to predict this build-up, it is essential to recognize and understand their role. Gravitational settling with drag has primarily been considered in this context. However, since flow in water distribution pipes is nearly always in the turbulent regime, turbulent processes should be considered also. In addition to these, single particle effects and forces may affect radial particle transport. In this work, we present an application of a previously published turbulent particle deposition theory to conditions relevant for drinking water distribution systems. We predict quantitatively under which conditions turbophoresis, including the virtual mass effect, the Saffman lift force, and the Magnus force may contribute significantly to sediment transport in radial direction and compare these results to experimental observations. The contribution of turbophoresis is mostly limited to large particles (>50 μm) in transport mains, and not expected to play a major role in distribution mains. The Saffman lift force may enhance this process to some degree. The Magnus force is not expected to play any significant role in drinking water distribution systems. © 2010 Elsevier Ltd. All rights reserved.

The Global Distribution of Precipitation and Clouds. Chapter 2.4

NASA Technical Reports Server (NTRS)

Shepherd, J. Marshall; Adler, Robert; Huffman, George; Rossow, William; Ritter, Michael; Curtis, Scott

2004-01-01

The water cycle is the key circuit moving water through the Earth's system. This large system, powered by energy from the sun, is a continuous exchange of moisture between the oceans, the atmosphere, and the land. Precipitation (including rain, snow, sleet, freezing rain, and hail), is the primary mechanism for transporting water from the atmosphere back to the Earth's surface and is the key physical process that links aspects of climate, weather, and the global water cycle. Global precipitation and associate cloud processes are critical for understanding the water cycle balance on a global scale and interactions with the Earth's climate system. However, unlike measurement of less dynamic and more homogenous meteorological fields such as pressure or even temperature, accurate assessment of global precipitation is particularly challenging due to its highly stochastic and rapidly changing nature. It is not uncommon to observe a broad spectrum of precipitation rates and distributions over very localized time scales. Furthermore, precipitating systems generally exhibit nonhomogeneous spatial distributions of rain rates over local to global domains.

On the way to identify microorganisms in drinking water distribution networks via DNA analysis of the gut content of freshwater isopods.

PubMed

Mayer, Michael; Keller, Adrian; Szewzyk, Ulrich; Warnecke, Hans-Joachim

2015-05-10

Pure drinking water is the basis for a healthy society. In Germany the drinking water regulations demand for analysis of water via detection of certain microbiological parameters by cultivation only. However, not all prokaryotes can be detected by these standard methods. How to gain more and better information about the bacteria present in drinking water and its distribution systems? The biofilms in drinking water distribution systems are built by bacteria and therefore represent a valuable source of information about the species present. Unfortunately, these biofilms are badly accessible. We thus exploited the circumstance that a lot of metazoans graze the biofilms, so that the content of their guts partly reflects the respective biofilm biocenosis. Therefore, we collected omnivorous isopods, prepared their guts and examined and characterized their contents based on 16S und 18S rDNA analysis. These molecularbiological investigations provide a profound basis for the characterization of the biocenosis and thereby biologically assess the drinking water ecosystems. Combined with a thorough identification of the species and the knowledge of their habitats, this approach can provide useful indications for the assessment of drinking-water quality and the early detection of problems in the distribution system. Copyright © 2015 Elsevier B.V. All rights reserved.

Condition Assessment Technologies for Water Transmission and Distribution Systems

EPA Science Inventory

As part of the U.S. Environmental Protection Agency’s (EPA’s) Aging Water Infrastructure Research Program, this research was conducted to identify and characterize the state of the technology for structural condition assessment of drinking water transmission and distribution syst...

A Geology-Based Estimate of Connate Water Salinity Distribution

DTIC Science & Technology

2014-09-01

poses serious environmental concerns if connate water is mobilized into shallow aquifers or surface water systems. Estimating the distribution of...groundwater flow and salinity transport near the Herbert Hoover Dike (HHD) surrounding Lake Okeechobee in Florida . The simulations were conducted using the...on the geologic configuration at equilibrium, and the horizontal salinity distribution is strongly linked to aquifer connectivity because

Getting the lead out: understanding risks in the distribution ...

EPA Pesticide Factsheets

This presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation measures such as filters); and holistic approaches and/or strategies that could be used to avoid unintended consequences of decisions from source to tap. Invited presentation on topics indicated as of interest. With exposure to lead as the context, this presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation measures such as filters); and holistic approaches and/or strategies that could be used to avoid unintended consequences of decisions from source to tap.

Impact of Nitrification on the Formation of N-Nitrosamines and Halogenated Disinfection Byproducts within Distribution System Storage Facilities.

PubMed

Zeng, Teng; Mitch, William A

2016-03-15

Distribution system storage facilities are a critical, yet often overlooked, component of the urban water infrastructure. This study showed elevated concentrations of N-nitrosodimethylamine (NDMA), total N-nitrosamines (TONO), regulated trihalomethanes (THMs) and haloacetic acids (HAAs), 1,1-dichloropropanone (1,1-DCP), trichloroacetaldehyde (TCAL), haloacetonitriles (HANs), and haloacetamides (HAMs) in waters with ongoing nitrification as compared to non-nitrifying waters in storage facilities within five different chloraminated drinking water distribution systems. The concentrations of NDMA, TONO, HANs, and HAMs in the nitrifying waters further increased upon application of simulated distribution system chloramination. The addition of a nitrifying biofilm sample collected from a nitrifying facility to its non-nitrifying influent water led to increases in N-nitrosamine and halogenated DBP formation, suggesting the release of precursors from nitrifying biofilms. Periodic treatment of two nitrifying facilities with breakpoint chlorination (BPC) temporarily suppressed nitrification and reduced precursor levels for N-nitrosamines, HANs, and HAMs, as reflected by lower concentrations of these DBPs measured after re-establishment of a chloramine residual within the facilities than prior to the BPC treatment. However, BPC promoted the formation of halogenated DBPs while a free chlorine residual was maintained. Strategies that minimize application of free chlorine while preventing nitrification are needed to control DBP precursor release in storage facilities.

Vulnerability of water distribution systems to pathogen intrusion: how effective is a disinfectant residual?

PubMed

Propato, Marco; Uber, James G

2004-07-01

Can the spread of infectious disease through water distribution systems be halted by a disinfectant residual? This question is overdue for an answer. Regulatory agencies and water utilities have long been concerned about accidental intrusions of pathogens into distribution system pipelines (i.e., cross-connections) and are increasingly concerned about deliberate pathogen contamination. Here, a simulation framework is developed and used to assess the vulnerability of a water system to microbiological contamination. The risk of delivering contaminated water to consumers is quantified by a network water quality model that includes disinfectant decay and disinfection kinetics. The framework is applied to two example networks under a worst-case deliberate intrusion scenario. Results show that the risk of consumer exposure is affected by the residual maintenance strategy employed. The common regulation that demands a "detectable" disinfectant residual may not provide effective consumer protection against microbial contamination. A chloramine residual, instead of free chlorine, may significantly weaken this final barrier against pathogen intrusions. Moreover, the addition of a booster station at storage tanks may improve consumer protection without requiring excessive disinfectant.

Coliform non-compliance nightmares in water-supply distribution systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geldreich, E.E.

1988-01-01

Coliform occurrences in distribution systems have created a great concern for both utilities and water authorities because of the implied public-health implications and failure to meet Federal regulations. Many of the known cases involve systems in the east and midwest. The common denominator being systems that have significant amounts of pipe networks over 75 years old and all are treating surface waters. Origins for these contamination events can be found in source-water fluctuations, failures in treatment-barrier protection, or loss of pipe-network integrity. Once passage into the distribution network has been achieved, some of the coliforms (Klebsiella, Enterobacter, Citrobacter) and othermore » heterotrophic bacteria adapt to the pipe environment, finding protection and nutrient support in pipe sediments. Under conditions of seasonal warm waters (10 degC) and availability of assimilable organics in the pipe sediments and tubercles, colonization grows into biofilms that may slough-off into the water supply, creating a coliform non-compliance problem. Significance of these occurrences and control measures are part of a realistic action plan presented for guidance.« less

PROPOSED WATER QUALITY SURVEILLANCE NETWORK USING PHYSICAL, CHEMICAL AND BIOLOGICAL EARLY WARNING SYSTEMS (CBEWS)

EPA Science Inventory

The Homeland Protection Act of 2002 specifically calls for the investigation and use of Early Warning Systems (EWS) for water security reasons. The EWS is a screening tool for detecting changes in source water and distribution system water quality. A suite of time-relevant biol...

PROPOSED WATER QUALITY SURVEILLANCE NETWORK USING PHYSICAL, CHEMICAL AND BIOLOGICAL EARLY WARNING SYSTEMS (BEWS)

EPA Science Inventory

The Homeland Protection Act of 2002 specifically calls for the investigation and use of Early Warning Systems (EWS) for water security reasons. The EWS is a screening tool for detecting changes in source water and distribution system water quality. A suite of time-relevant biol...

Corrosion and scaling potential in drinking water distribution system of tabriz, northwestern iran.

PubMed

Taghipour, Hassan; Shakerkhatibi, Mohammad; Pourakbar, Mojtaba; Belvasi, Mehdi

2012-01-01

This paper discusses the corrosion and scaling potential of Tabriz drinking water distribution system in Northwest of Iran. Internal corrosion of piping is a serious problem in drinking water industry. Corrosive water can cause intrusion of heavy metals especially lead in to water, therefore effecting public health. The aim of this study was to determine corrosion and scaling potential in potable water distribution system of Tabriz during the spring and summer in 2011. This study was carried out using Langlier Saturation Index, Ryznar Stability Index, Puckorius Scaling Index, and Aggressiveness indices. Eighty samples were taken from all over the city within two seasons, spring, and summer. Related parameters including temperature, pH, total dissolved solids, calcium hardness, and total alkalinity in all samples were measured in laboratory according to standard method manual. For the statistical analysis of the results, SPSS software (version 11.5) was used The mean and standard deviation values of Langlier, Ryznar, Puckorius and Aggressiveness Indices were equal to -0.68 (±0.43), 8.43 (±0.55), 7.86 (±0.36) and 11.23 (±0.43), respectively. By survey of corrosion indices, it was found that Tabriz drinking water is corrosive. In order to corrosion control, it is suggested that laboratorial study with regard to the distribution system condition be carried out to adjust effective parameters such as pH.

Review of cost versus scale: water and wastewater treatment and reuse processes.

PubMed

Guo, Tianjiao; Englehardt, James; Wu, Tingting

2014-01-01

The US National Research Council recently recommended direct potable water reuse (DPR), or potable water reuse without environmental buffer, for consideration to address US water demand. However, conveyance of wastewater and water to and from centralized treatment plants consumes on average four times the energy of treatment in the USA, and centralized DPR would further require upgradient distribution of treated water. Therefore, information on the cost of unit treatment processes potentially useful for DPR versus system capacity was reviewed, converted to constant 2012 US dollars, and synthesized in this work. A logarithmic variant of the Williams Law cost function was found applicable over orders of magnitude of system capacity, for the subject processes: activated sludge, membrane bioreactor, coagulation/flocculation, reverse osmosis, ultrafiltration, peroxone and granular activated carbon. Results are demonstrated versus 10 DPR case studies. Because economies of scale found for capital equipment are counterbalanced by distribution/collection network costs, further study of the optimal scale of distributed DPR systems is suggested.

Condition Assessment of Drinking Water Transmission and Distribution Systems

EPA Science Inventory

Condition assessment of water transmission and distribution mains is the collection of data and information through direct and/or indirect methods, followed by analysis of the data and information, to make a determination of the current and/or future structural, water quality, an...

Formation of biofilms in drinking water distribution networks, a case study in two cities in Finland and Latvia.

PubMed

Lehtola, Markku J; Juhna, Tālis; Miettinen, Ilkka T; Vartiainen, Terttu; Martikainen, Pertti J

2004-12-01

The formation of biofilms in drinking water distribution networks is a significant technical, aesthetic and hygienic problem. In this study, the effects of assimilable organic carbon, microbially available phosphorus (MAP), residual chlorine, temperature and corrosion products on the formation of biofilms were studied in two full-scale water supply systems in Finland and Latvia. Biofilm collectors consisting of polyvinyl chloride pipes were installed in several waterworks and distribution networks, which were supplied with chemically precipitated surface waters and groundwater from different sources. During a 1-year study, the biofilm density was measured by heterotrophic plate counts on R2A-agar, acridine orange direct counting and ATP-analyses. A moderate level of residual chlorine decreased biofilm density, whereas an increase of MAP in water and accumulated cast iron corrosion products significantly increased biofilm density. This work confirms, in a full-scale distribution system in Finland and Latvia, our earlier in vitro finding that biofilm formation is affected by the availability of phosphorus in drinking water.

Development, application, and sensitivity analysis of a water quality index for drinking water management in small systems.

PubMed

Scheili, A; Rodriguez, Manuel J; Sadiq, R

2015-11-01

The aim of this study was to produce a drinking water assessment tool for operators of small distribution systems. A drinking water quality index (DWQI) was developed and applied to small systems based on the water quality index of the Canadian Council of Ministers of Environment. The drinking water quality index was adapted to specific needs by creating four drinking water quality scenarios. First, the temporal and spatial dimensions of drinking water quality variability were taken into account. The DWQI was designed to express global drinking water quality according to different monitoring frequencies. Daily, monthly, and seasonal assessment was also considered. With the data made available, it was possible to use the index as a spatial monitoring tool and express water quality in different points in the distribution system. Moreover, adjustments were made to prioritize the type of contaminant to monitor. For instance, monitoring contaminants with acute health effects led to a scenario based on daily measures, including easily accessible and affordable water quality parameters. On the other hand, contaminants with chronic effects, especially disinfection by-products, were considered in a seasonal monitoring scenario where disinfection by-product reference values were redefined according to their seasonal variability. A sensitivity analysis was also carried out to validate the index. Globally, the DWQI developed is adapted to the needs of small systems. In fact, expressing drinking water quality using the DWQI contributes to the identification of problematic periods and segments in the distribution system. Further work may include this index in the development of a customized decision-making tool for small-system operators and managers.

Economic feasibility study of residential and commercial heating using existing water supply systems. Final report June 1, 1979 - August 15, 1979

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pitts, Donald R.; Looper, Marshall G.

1979-08-15

A study of the use of a low-to-moderate temperature hydrothermal resource for space heating a 140-home residential community has been undertake. The approach centers on use of the existing culinary/potable water supply system to supply heated water to the homes, the culinary water being heated at a single pumping station and then distributed throughout the community through uninsulated, buried water mains. The heated potable water is pumped through individual house water-to-air heat exchangers using sealed, magnetic-drive house pumps and returned to the street distribution lines. These house heat exchangers are either add-on, wall mounted, convective heating units or coils addedmore » to existing forced air heating systems.« less

Study of water supply & sanitation practices in India using geographic information systems: some design & other considerations in a village setting.

PubMed

Gopal, Srila; Sarkar, Rajiv; Banda, Kalyan; Govindarajan, Jeyanthi; Harijan, B B; Jeyakumar, M B; Mitta, Philip; Sadanala, M E; Selwyn, Tryphena; Suresh, C R; Thomas, V A; Devadason, Pethuru; Kumar, Ranjit; Selvapandian, David; Kang, Gagandeep; Balraj, Vinohar

2009-03-01

Availability of clean water and adequate sanitation facilities are of prime importance for limiting diarrhoeal diseases. We examined the water and sanitation facilities of a village in southern India using geographic information system (GIS) tools. Places of residence, water storage and distribution, sewage and places where people in the village defaecated were mapped and drinking water sources were tested for microbial contamination in Nelvoy village, Vellore district, Tamil Nadu. Water in the village was found to be microbiologically unfit for consumption. Analysis using direct observations supplemented by GIS maps revealed poor planning, poor engineering design and lack of policing of the water distribution system causing possible contamination of drinking water from sewage at multiple sites. Until appropriate engineering designs for water supply and sewage disposal to suit individual village needs are made available, point-of-use water disinfection methods could serve as an interim solution.

Where is the state? How is the state? Accessing water and the state in Mumbai and Johannesburg.

PubMed

Bawa, Zainab

2011-01-01

This article examines the water distribution systems in Johannesburg and Mumbai to argue that the political and institutional contexts of service delivery shape people’s access to the state and its resources, and also mediation between citizens and government institutions by councillors. Through ethnographies of water supply and distribution systems in Mumbai and Johannesburg, I explain how the organizational structure of the water utility, institutional arrangements of service delivery, regulatory systems, councillors’ proximity to decision makers and their relationship with municipal officials, civil servants and party members variously influence councillors’ mediation capacities and their ability to fulfil the claims of their constituencies for piped water supply and connections.

Comparison between Synthesized Lead Particles and Lead Solids Formed on Surfaces in Real Drinking Water Distribution Systems

EPA Science Inventory

The objective of this work is to compare the properties of lead solids formed during bench-scale precipitation experiments to solids found on lead pipe removed from real drinking water distribution systems and metal coupons used in pilot scale corrosion testing. Specifically, so...

THE MINERALOGY OF PB SCALES IN DRINKING WATER DISTRIBUTION SYSTEMS AS REVEALED BY COMBINED XRD AND MICRO-RAMAN SPECTROSCOPY

EPA Science Inventory

Dissolving Pb from lead service lines and Pb-containing brasses and solders has become a major health issue for many water distribution systems. Knowledge of the mineralogy of scales in these pipes is key to modeling this dissolution. The traditional method of determining their ...

PHYLOGENETIC AFFILIATION OF WATER DISTRIBUTION SYSTEM BACTERIAL ISOLATES USING 16S RDNA SEQUENCE ANALYSIS

EPA Science Inventory

In a previously described study, only 15% of the bacterial strains isolated from a water distribution system (WDS) grown on R2A agar were identifiable using fatty acid methyl esthers (FAME) profiling. The lack of success was attributed to the use of fatty acid databases of bacter...

[Development and application of a multi-species water quality model for water distribution systems with EPANET-MSX].

PubMed

Sun, Fu; Chen, Ji-ning; Zeng, Si-yu

2008-12-01

A conceptual multi-species water quality model for water distribution systems was developed on the basis of the toolkit of the EPANET-MSX software. The model divided the pipe segment into four compartments including pipe wall, biofilm, boundary layer and bulk liquid. The involved processes were substrate utilization and microbial growth, decay and inactivation of microorganisms, mass transfer of soluble components through the boundary layer, adsorption and desorption of particular components between bulk liquid and biofilm, oxidation and halogenation of organic matter by residual chlorine, and chlorine consumption by pipe wall. The fifteen simulated variables included the seven common variables both in the biofilm and in the bulk liquid, i.e. soluble organic matter, particular organic matter, ammonia nitrogen, residual chlorine, heterotrophic bacteria, autotrophic bacteria and inert solids, as well as biofilm thickness on the pipe wall. The model was validated against the data from a series of pilot experiments, and the simulation accuracy for residual chlorine and turbidity were 0.1 mg/L and 0.3 NTU respectively. A case study showed that the model could reasonably reflect the dynamic variation of residual chlorine and turbidity in the studied water distribution system, while Monte Carlo simulation, taking into account both the variability of finished water from the waterworks and the uncertainties of model parameters, could be performed to assess the violation risk of water quality in the water distribution system.

Estimates of water source contributions in a dynamic urban water supply system inferred via a Bayesian stable isotope mixing model

NASA Astrophysics Data System (ADS)

Jameel, M. Y.; Brewer, S.; Fiorella, R.; Tipple, B. J.; Bowen, G. J.; Terry, S.

2017-12-01

Public water supply systems (PWSS) are complex distribution systems and critical infrastructure, making them vulnerable to physical disruption and contamination. Exploring the susceptibility of PWSS to such perturbations requires detailed knowledge of the supply system structure and operation. Although the physical structure of supply systems (i.e., pipeline connection) is usually well documented for developed cities, the actual flow patterns of water in these systems are typically unknown or estimated based on hydrodynamic models with limited observational validation. Here, we present a novel method for mapping the flow structure of water in a large, complex PWSS, building upon recent work highlighting the potential of stable isotopes of water (SIW) to document water management practices within complex PWSS. We sampled a major water distribution system of the Salt Lake Valley, Utah, measuring SIW of water sources, treatment facilities, and numerous sites within in the supply system. We then developed a hierarchical Bayesian (HB) isotope mixing model to quantify the proportion of water supplied by different sources at sites within the supply system. Known production volumes and spatial distance effects were used to define the prior probabilities for each source; however, we did not include other physical information about the supply system. Our results were in general agreement with those obtained by hydrodynamic models and provide quantitative estimates of contributions of different water sources to a given site along with robust estimates of uncertainty. Secondary properties of the supply system, such as regions of "static" and "dynamic" source (e.g., regions supplied dominantly by one source vs. those experiencing active mixing between multiple sources), can be inferred from the results. The isotope-based HB isotope mixing model offers a new investigative technique for analyzing PWSS and documenting aspects of supply system structure and operation that are otherwise challenging to observe. The method could allow water managers to document spatiotemporal variation in PWSS flow patterns, critical for interrogating the distribution system to inform operation decision making or disaster response, optimize water supply and, monitor and enforce water rights.

Distributed sensor for water and pH measurements using fiber optics and swellable polymeric systems

NASA Astrophysics Data System (ADS)

Michie, W. C.; Culshaw, B.; McKenzie, I.; Konstantakis, M.; Graham, N. B.; Moran, C.; Santos, F.; Bergqvist, E.; Carlstrom, B.

1995-01-01

We report on the design, construction and test of a generic form of sensor for making distributed measurements of a range of chemical parameters. The technique combines optical time-domain reflectometry with chemically sensitive water-swellable polymers (hydrogels). Initial experiments have concentrated on demonstrating a distributed water detector; however, gels have been developed that enable this sensor to be

Better Water Demand and Pipe Description Improve the Distribution Network Modeling Results

EPA Science Inventory

Distribution system modeling simplifies pipe network in skeletonization and simulates the flow and water quality by using generalized water demand patterns. While widely used, the approach has not been examined fully on how it impacts the modeling fidelity. This study intends to ...

Monitoring bacterial contamination of piped water supply in rural coastal Bangladesh.

PubMed

Ahsan, Md Sabbir; Akber, Md Ali; Islam, Md Atikul; Kabir, Md Pervez; Hoque, Md Ikramul

2017-10-31

Safe drinking water is scarce in southwest coastal Bangladesh because of unavailability of fresh water. Given the high salinity of both groundwater and surface water in this area, harvested rainwater and rain-fed pond water became the main sources of drinking water. Both the government and non-government organizations have recently introduced pipe water supply in the rural coastal areas to ensure safe drinking water. We assessed the bacteriological quality of water at different points along the piped water distribution system (i.e., the source, treatment plant, household taps, street hydrants, and household storage containers) of Mongla municipality under Mongla Upazila in Bagerhat district. Water samples were collected at 2-month interval from May 2014 to March 2015. Median E. coli and total coliform counts at source, treatment plant, household taps, street hydrants, and household storage containers were respectively 225, 4, 7, 7, and 15 cfu/100 ml and 42,000, 545, 5000, 6150, and 18,800 cfu/100 ml. Concentrations of both of the indicator bacteria reduced after treatment, although it did not satisfy the WHO drinking water standards. However, re-contamination in distribution systems and household storage containers indicate improper maintenance of distribution system and lack of personal hygiene.

Persistence of pharmaceuticals and other organic compounds in chlorinated drinking water as a function of time

USGS Publications Warehouse

Gibs, J.; Stackelberg, P.E.; Furlong, E.T.; Meyer, M.; Zaugg, S.D.; Lippincott, R.L.

2007-01-01

Ninety eight pharmaceuticals and other organic compounds (POOCs) that were amended to samples of chlorinated drinking-water were extracted and analyzed 1, 3, 6, 8, and 10 days after amendment to determine whether the total chlorine residual reacted with the amended POOCs in drinking water in a time frame similar to the residence time of drinking water in a water distribution system. Results indicated that if all 98 were present in the finished drinking water from a drinking-water treatment plant using free chlorine at 1.2??mg/L as the distribution system disinfectant residual, 52 POOCs would be present in the drinking water after 10??days at approximately the same concentration as in the newly finished drinking water. Concentrations of 16 POOCs would be reduced by 32% to 92%, and 22 POOCs would react completely with residual chlorine within 24??h. Thus, the presence of free chlorine residual is an effective means for transforming some POOCs during distribution. ?? 2006 Elsevier B.V. All rights reserved.

Persistence of pharmaceuticals and other organic compounds in chlorinated drinking water as a function of time.

PubMed

Gibs, Jacob; Stackelberg, Paul E; Furlong, Edward T; Meyer, Michael; Zaugg, Steven D; Lippincott, Robert Lee

2007-02-01

Ninety eight pharmaceuticals and other organic compounds (POOCs) that were amended to samples of chlorinated drinking-water were extracted and analyzed 1, 3, 6, 8, and 10 days after amendment to determine whether the total chlorine residual reacted with the amended POOCs in drinking water in a time frame similar to the residence time of drinking water in a water distribution system. Results indicated that if all 98 were present in the finished drinking water from a drinking-water treatment plant using free chlorine at 1.2 mg/L as the distribution system disinfectant residual, 52 POOCs would be present in the drinking water after 10 days at approximately the same concentration as in the newly finished drinking water. Concentrations of 16 POOCs would be reduced by 32% to 92%, and 22 POOCs would react completely with residual chlorine within 24 h. Thus, the presence of free chlorine residual is an effective means for transforming some POOCs during distribution.

SILICATES FOR CORROSION CONTROL IN BUILDING POTABLE WATER SYSTEMS

EPA Science Inventory

Silicates have been used to control the corrosion of drinking water distribution system materials. Previous work has shown that they are particularly useful in reducing the release of zinc from galvanized materials in hot water systems. Negatively charged silicate species were re...

Pyrosequence Analysis of the hsp65 Genes of Nontuberculous Mycobacterium Communities in Unchlorinated Drinking Water in the Netherlands

PubMed Central

Heijnen, Leo; van der Kooij, Dick

2013-01-01

Studies have shown that certain opportunistic pathogenic species of nontuberculous mycobacteria (NTM) can be present in distributed drinking water. However, detailed information about NTM population composition in drinking water is lacking. Therefore, NTM communities in unchlorinated drinking water from the distribution system of five treatment plants in the Netherlands were characterized using 454 pyrosequencing of the hsp65 gene. Results showed high diversities in unchlorinated drinking water, with up to 28 different NTM operational taxonomic units (OTUs) in a single sample. Each drinking water sample had a unique NTM community, and most (81.1%) OTUs were observed only once. One OTU was observed in 14 of 16 drinking water samples, indicating that this NTM species is well adapted to unchlorinated drinking water conditions. A clear influence of season, source type (groundwater, surface water), easily assimilable organic carbon (AOC) concentration, biofilm formation rate, and active biomass in treated water on the establishment of an NTM community in drinking water was not observed. Apparently, local conditions are more important for the development of a specific NTM community in the drinking water distribution system. A low (4.2%) number of hsp65 gene sequences showed more than 97% similarity to sequences of the opportunistic pathogens M. avium, M. genavense, and M. gordonae. However, most (95.8%) NTM hsp65 gene sequences were related to not-yet-described NTM species that have not been linked to disease, indicating that most NTM species in unchlorinated drinking water from distribution systems in the Netherlands have a low public health significance. PMID:23913420

Pyrosequence analysis of the hsp65 genes of nontuberculous mycobacterium communities in unchlorinated drinking water in the Netherlands.

PubMed

van der Wielen, Paul W J J; Heijnen, Leo; van der Kooij, Dick

2013-10-01

Studies have shown that certain opportunistic pathogenic species of nontuberculous mycobacteria (NTM) can be present in distributed drinking water. However, detailed information about NTM population composition in drinking water is lacking. Therefore, NTM communities in unchlorinated drinking water from the distribution system of five treatment plants in the Netherlands were characterized using 454 pyrosequencing of the hsp65 gene. Results showed high diversities in unchlorinated drinking water, with up to 28 different NTM operational taxonomic units (OTUs) in a single sample. Each drinking water sample had a unique NTM community, and most (81.1%) OTUs were observed only once. One OTU was observed in 14 of 16 drinking water samples, indicating that this NTM species is well adapted to unchlorinated drinking water conditions. A clear influence of season, source type (groundwater, surface water), easily assimilable organic carbon (AOC) concentration, biofilm formation rate, and active biomass in treated water on the establishment of an NTM community in drinking water was not observed. Apparently, local conditions are more important for the development of a specific NTM community in the drinking water distribution system. A low (4.2%) number of hsp65 gene sequences showed more than 97% similarity to sequences of the opportunistic pathogens M. avium, M. genavense, and M. gordonae. However, most (95.8%) NTM hsp65 gene sequences were related to not-yet-described NTM species that have not been linked to disease, indicating that most NTM species in unchlorinated drinking water from distribution systems in the Netherlands have a low public health significance.

Sensor-enabled chem/bio contamination detection system dedicated to situational awareness of water distribution security status

NASA Astrophysics Data System (ADS)

Ginsberg, Mark D.; Smith, Eddy D.; VanBlaricum, Vicki; Hock, Vincent F.; Kroll, Dan; Russell, Kevin J.

2010-04-01

Both real events and models have proven that drinking water systems are vulnerable to deliberate and/or accidental contamination. Additionally, homeland security initiatives and modeling efforts have determined that it is relatively easy to orchestrate the contamination of potable water supplies. Such contamination can be accomplished with classic and non-traditional chemical agents, toxic industrial chemicals (TICs), and/or toxic industrial materials (TIMs). Subsequent research and testing has developed a proven network for detection and response to these threats. The method uses offthe- shelf, broad-spectrum analytical instruments coupled with advanced interpretive algorithms. The system detects and characterizes any backflow events involving toxic contaminants by employing unique chemical signature (fingerprint) response data. This instrumentation has been certified by the Office of Homeland Security for detecting deliberate and/or accidental contamination of critical water infrastructure. The system involves integration of several mature technologies (sensors, SCADA, dynamic models, and the HACH HST Guardian Blue instrumentation) into a complete, real-time, management system that also can be used to address other water distribution concerns, such as corrosion. This paper summarizes the reasons and results for installing such a distribution-based detection and protection system.

Assessment of water pipes durability under pressure surge

NASA Astrophysics Data System (ADS)

Pham Ha, Hai; Minh, Lanh Pham Thi; Tang Van, Lam; Bulgakov, Boris; Bazhenova, Soafia

2017-10-01

Surge phenomenon occurs on the pipeline by the closing valve or pump suddenly lost power. Due to the complexity of the water hammer simulation, previous researches have only considered water hammer on the single pipe or calculation of some positions on water pipe network, it have not been analysis for all of pipe on the water distribution systems. Simulation of water hammer due to closing valve on water distribution system and the influence level of pressure surge is evaluated at the defects on pipe. Water hammer on water supply pipe network are simulated by Water HAMMER software academic version and the capacity of defects are calculated by SINTAP. SINTAP developed from Brite-Euram projects in Brussels-Belgium with the aim to develop a process for assessing the integrity of the structure for the European industry. Based on the principle of mechanical fault, indicating the size of defects in materials affect the load capacity of the product in the course of work, the process has proposed setting up the diagram to fatigue assessment defect (FAD). The methods are applied for water pipe networks of Lien Chieu district, Da Nang city, Viet Nam, the results show the affected area of wave pressure by closing the valve and thereby assess the greatest pressure surge effect to corroded pipe. The SINTAP standard and finite element mesh analysis at the defect during the occurrence of pressure surge which will accurately assess the bearing capacity of the old pipes. This is one of the bases to predict the leakage locations on the water distribution systems. Amount of water hammer when identified on the water supply networks are decreasing due to local losses at the nodes as well as the friction with pipe wall, so this paper adequately simulate water hammer phenomena applying for actual water distribution systems. The research verified that pipe wall with defect is damaged under the pressure surge value.

40 CFR 141.401 - Sanitary surveys for ground water systems.

Code of Federal Regulations, 2012 CFR

2012-07-01

...: (1) Source, (2) Treatment, (3) Distribution system, (4) Finished water storage, (5) Pumps, pump facilities, and controls, (6) Monitoring, reporting, and data verification, (7) System management and...

40 CFR 141.401 - Sanitary surveys for ground water systems.

Code of Federal Regulations, 2013 CFR

2013-07-01

...: (1) Source, (2) Treatment, (3) Distribution system, (4) Finished water storage, (5) Pumps, pump facilities, and controls, (6) Monitoring, reporting, and data verification, (7) System management and...

E.M.I Effects of Cathodic Protection on Electromagnetic Flowmeters

PubMed Central

Gundogdu, Serdar; Sahin, Ozge

2007-01-01

Electromagnetic flowmeters are used to measure the speed of water flow in water distribution systems. Corrosion problem in metal pipelines can be solved by cathodic protection methods. This paper presents a research on corruptive effects of the cathodic protection system on electromagnetic flowmeter depending on its measuring principle. Experimental measurements are realized on the water distribution pipelines of the Izmir Municipality, Department of Water and Drainage Administration (IZSU) in Turkey and measurement results are given. Experimental results proved that the values measured by the electromagnetic flowmeter (EMF) are affected by cathodic protection system current. Comments on the measurement results are made and precautions to be taken are proposed.

Preliminary classification of water areas within the Atchafalaya Basin Floodway System by using landsat imagery

USGS Publications Warehouse

Allen, Yvonne C.; Constant, Glenn C.; Couvillion, Brady R.

2008-01-01

The southern portion of the Atchafalaya Basin Floodway System (ABFS) is a large area (2,571 km2) in south central Louisiana bounded on the east and west sides by a levee system. The ABFS is a sparsely populated area that includes some of the Nation's most significant extents of bottomland hardwoods, swamps, bayous, and backwater lakes, holding a rich abundance and diversity of terrestrial and aquatic species. The seasonal flow of water through the ABFS is critical to maintaining its ecological integrity. Because of strong interdependencies among species, habitat quality, and water flow in the ABFS, there is a need to better define the paths by which water moves at various stages of the hydrocycle. Although river level gages have collected a long historical record of water level variation, very little synoptic information has been available regarding the distribution and character of water at more remote locations in the basin. Most water management plans for the ABFS strive to improve water quality by increasing water flow and circulation from the main stem of the Atchafalaya River into isolated areas. To describe the distribution of land and water on a basin-wide scale, we chose to use Landsat 5 and Landsat 7 imagery to determine the extent of water distribution from 1985 to 2006 and at a variety of river stages. Because the visual signature of river water is high turbidity, we also used Landsat imagery to describe the distribution of turbid water in the ABFS. The ability to track water flow patterns by tracking turbid waters will enhance the characterization of water movement and aid in planning.

Intermittent Water Supply: Prevalence, Practice, and Microbial Water Quality.

PubMed

Kumpel, Emily; Nelson, Kara L

2016-01-19

Intermittent water supplies (IWS), in which water is provided through pipes for only limited durations, serve at least 300 million people around the world. However, providing water intermittently can compromise water quality in the distribution system. In IWS systems, the pipes do not supply water for periods of time, supply periods are shortened, and pipes experience regular flow restarting and draining. These unique behaviors affect distribution system water quality in ways that are different than during normal operations in continuous water supplies (CWS). A better understanding of the influence of IWS on mechanisms causing contamination can help lead to incremental steps that protect water quality and minimize health risks. This review examines the status and nature of IWS practices throughout the world, the evidence of the effect of IWS on water quality, and how the typical contexts in which IWS systems often exist-low-income countries with under-resourced utilities and inadequate sanitation infrastructure-can exacerbate mechanisms causing contamination. We then highlight knowledge gaps for further research to improve our understanding of water quality in IWS.

Advanced Decentralized Water/Energy Network Design for Sustainable Infrastructure

EPA Science Inventory

In order to provide a water infrastructure that is more sustainable into and beyond the 21st century, drinking water distribution systems and wastewater collection systems must account for our diminishing water supply, increasing demands, climate change, energy cost and availabil...

INVESTIGATION OF SEQUENTIAL AND ENZYMATIC EXTRACTION OF ARSENIC FROM DRINKING WATER DISTRIBUTION SOLIDS WITH ICP-MS

EPA Science Inventory

A sequential extraction approach was utilized to estimate the distribution of arsenite [As(III)] and arsenate [As(V)] on iron oxide/hydroxide solids obtained from drinking water distribution systems. The arsenic (As) associated with these solids can be segregated into three oper...

An experimental study on the influence of water stagnation and temperature change on water quality in a full-scale domestic drinking water system.

PubMed

Zlatanović, Lj; van der Hoek, J P; Vreeburg, J H G

2017-10-15

The drinking water quality changes during the transport through distribution systems. Domestic drinking water systems (DDWSs), which include the plumbing between the water meter and consumer's taps, are the most critical points in which water quality may be affected. In distribution networks, the drinking water temperature and water residence time are regarded as indicators of the drinking water quality. This paper describes an experimental research on the influence of stagnation time and temperature change on drinking water quality in a full-scale DDWS. Two sets of stagnation experiments, during winter and summer months, with various stagnation intervals (up to 168 h of stagnation) were carried out. Water and biofilms were sampled at two different taps, a kitchen and a shower tap. Results from this study indicate that temperature and water stagnation affect both chemical and microbial quality in DDWSs, whereas microbial parameters in stagnant water appear to be driven by the temperature of fresh water. Biofilm formed in the shower pipe contained more total and intact cells than the kitchen pipe biofilm. Alphaproteobacteria were found to dominate in the shower biofilm (78% of all Proteobacteria), while in the kitchen tap biofilm Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria were evenly distributed. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Design Considerations for a Water Treatment System Utilizing Ultra-Violet Light Emitting Diodes

DTIC Science & Technology

2014-03-27

DESIGN CONSIDERATIONS FOR A WATER TREATMENT SYSTEM UTILIZING ULTRA-VIOLET LIGHT EMITTING DIODES...the United States. ii AFIT-ENV-14-M-58 DESIGN CONSIDERATIONS FOR A WATER TREATMENT SYSTEM UTILIZING ULTRA-VIOLET LIGHT EMITTING DIODES...DISTRIBUTION UNLIMITED. iii AFIT-ENV-14-M-58 DESIGN CONSIDERATIONS FOR A WATER TREATMENT SYSTEM UTILIZING ULTRA-VIOLET LIGHT EMITTING

Ammonia- and nitrite-oxidizing bacterial communities in a pilot-scale chloraminated drinking water distribution system.

PubMed

Regan, John M; Harrington, Gregory W; Noguera, Daniel R

2002-01-01

Nitrification in drinking water distribution systems is a common operational problem for many utilities that use chloramines for secondary disinfection. The diversity of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) in the distribution systems of a pilot-scale chloraminated drinking water treatment system was characterized using terminal restriction fragment length polymorphism (T-RFLP) analysis and 16S rRNA gene (ribosomal DNA [rDNA]) cloning and sequencing. For ammonia oxidizers, 16S rDNA-targeted T-RFLP indicated the presence of Nitrosomonas in each of the distribution systems, with a considerably smaller peak attributable to Nitrosospira-like AOB. Sequences of AOB amplification products aligned within the Nitrosomonas oligotropha cluster and were closely related to N. oligotropha and Nitrosomonas ureae. The nitrite-oxidizing communities were comprised primarily of Nitrospira, although Nitrobacter was detected in some samples. These results suggest a possible selection of AOB related to N. oligotropha and N. ureae in chloraminated systems and demonstrate the presence of NOB, indicating a biological mechanism for nitrite loss that contributes to a reduction in nitrite-associated chloramine decay.

Ammonia- and Nitrite-Oxidizing Bacterial Communities in a Pilot-Scale Chloraminated Drinking Water Distribution System

PubMed Central

Regan, John M.; Harrington, Gregory W.; Noguera, Daniel R.

2002-01-01

Nitrification in drinking water distribution systems is a common operational problem for many utilities that use chloramines for secondary disinfection. The diversity of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) in the distribution systems of a pilot-scale chloraminated drinking water treatment system was characterized using terminal restriction fragment length polymorphism (T-RFLP) analysis and 16S rRNA gene (ribosomal DNA [rDNA]) cloning and sequencing. For ammonia oxidizers, 16S rDNA-targeted T-RFLP indicated the presence of Nitrosomonas in each of the distribution systems, with a considerably smaller peak attributable to Nitrosospira-like AOB. Sequences of AOB amplification products aligned within the Nitrosomonas oligotropha cluster and were closely related to N. oligotropha and Nitrosomonas ureae. The nitrite-oxidizing communities were comprised primarily of Nitrospira, although Nitrobacter was detected in some samples. These results suggest a possible selection of AOB related to N. oligotropha and N. ureae in chloraminated systems and demonstrate the presence of NOB, indicating a biological mechanism for nitrite loss that contributes to a reduction in nitrite-associated chloramine decay. PMID:11772611

Mineralogical and Molecular Microbial Characterization of a Lead Pipe Removed from a Drinking Water Distribution System

EPA Science Inventory

The U.S. Environmental Protection Agency's (US EPA) Lead and Copper Rule established an action level for lead of 0.0 15 mg/L in a 1 liter first draw sample at the consumer's tap. Lead corrosion and solubility in drinking water distribution systems are largely controlled by the fo...

A component-based, integrated spatially distributed hydrologic/water quality model: AgroEcoSystem-Watershed (AgES-W) overview and application

USDA-ARS?s Scientific Manuscript database

AgroEcoSystem-Watershed (AgES-W) is a modular, Java-based spatially distributed model which implements hydrologic/water quality simulation components. The AgES-W model was previously evaluated for streamflow and recently has been enhanced with the addition of nitrogen (N) and sediment modeling compo...

The Spatially-Distributed Agroecosystem-Watershed (Ages-W) Hydrologic/Water Quality (H/WQ) model for assessment of conservation effects

USDA-ARS?s Scientific Manuscript database

AgroEcoSystem-Watershed (AgES-W) is a modular, Java-based spatially distributed model which implements hydrologic/water quality (H/WQ) simulation components under the Object Modeling System (OMS3) environmental modeling framework. AgES-W has recently been enhanced with the addition of nitrogen (N) a...

THE RELATIONSHIP BETWEEN THE CORROSION OF DISTRIBUTION SYSTEM MATERIALS, AND OXIDANT AND REDOX POTENTIAL

EPA Science Inventory

Scale build-up, corrosion rate, and metal release associated with drinking water distribution system pipes have been suggested to relate to the oxidant type and concentration. Conversely, different distribution system metals may exert different oxidant demands. The impact of ox...

Modeling integrated water user decisions in intermittent supply systems

NASA Astrophysics Data System (ADS)

Rosenberg, David E.; Tarawneh, Tarek; Abdel-Khaleq, Rania; Lund, Jay R.

2007-07-01

We apply systems analysis to estimate household water use in an intermittent supply system considering numerous interdependent water user behaviors. Some 39 household actions include conservation; improving local storage or water quality; and accessing sources having variable costs, availabilities, reliabilities, and qualities. A stochastic optimization program with recourse decisions identifies the infrastructure investments and short-term coping actions a customer can adopt to cost-effectively respond to a probability distribution of piped water availability. Monte Carlo simulations show effects for a population of customers. Model calibration reproduces the distribution of billed residential water use in Amman, Jordan. Parametric analyses suggest economic and demand responses to increased availability and alternative pricing. It also suggests potential market penetration for conservation actions, associated water savings, and subsidies to entice further adoption. We discuss new insights to size, target, and finance conservation.

Distribution of pesticides in n-hexane/water and n-hexane/acetonitrile systems and estimation of possibilities of their extraction isolation and preconcentration from various matrices.

PubMed

Zayats, M F; Leschev, S M; Petrashkevich, N V; Zayats, M A; Kadenczki, L; Szitás, R; Szemán Dobrik, H; Keresztény, N

2013-04-24

Distribution of 150 most widely used pesticides of different chemical classes (amides, anilinopirimidines, aromatics, benzenesulfonates, carbamates, dicarboximides, organophosphorus compounds, phenyl esters, phenylureas, pyrazoles, pyrethroids, pyrimidines, strobilurins, sulfamides, triazines, triazoles, etc.) in n-hexane/water and n-hexane/acetonitrile systems was investigated at 25°C. Distribution constants of pesticides (P) have been calculated as ratio of pesticide concentration in n-hexane to its concentration in water or acetonitrile phase. HPLC and GC methods were used for pesticides determination in phases. It was found that the overwhelming majority of pesticides are hydrophobic, i.e. in n-hexane/water system LgP≫0, and the difference in LgP values can reach 9.1 units. Replacement of water for acetonitrile leads to dramatic fall of LgP values reaching 9.5 units. The majority of LgP values in this case are negative and their differences is strongly leveled in comparison with a hexane/water system. Thus, maximal difference in pesticides LgP values for n-hexane/acetonitrile system is 3.2 units. It is shown that n-hexane can be used for selective and efficient extraction and preconcentration of pesticides from water matrices. On the other hand, acetonitrile is effective for the isolation and preconcentration of pesticides from hydrocarbon and vegetable oil matrices. The distribution constants described in the paper may be effectively used for the estimation of possibilities of extraction isolation, preconcentration and separation of pesticides. Copyright © 2013 Elsevier B.V. All rights reserved.

Methodology and application of combined watershed and ground-water models in Kansas

USGS Publications Warehouse

Sophocleous, M.; Perkins, S.P.

2000-01-01

Increased irrigation in Kansas and other regions during the last several decades has caused serious water depletion, making the development of comprehensive strategies and tools to resolve such problems increasingly important. This paper makes the case for an intermediate complexity, quasi-distributed, comprehensive, large-watershed model, which falls between the fully distributed, physically based hydrological modeling system of the type of the SHE model and the lumped, conceptual rainfall-runoff modeling system of the type of the Stanford watershed model. This is achieved by integrating the quasi-distributed watershed model SWAT with the fully-distributed ground-water model MODFLOW. The advantage of this approach is the appreciably smaller input data requirements and the use of readily available data (compared to the fully distributed, physically based models), the statistical handling of watershed heterogeneities by employing the hydrologic-response-unit concept, and the significantly increased flexibility in handling stream-aquifer interactions, distributed well withdrawals, and multiple land uses. The mechanics of integrating the component watershed and ground-water models are outlined, and three real-world management applications of the integrated model from Kansas are briefly presented. Three different aspects of the integrated model are emphasized: (1) management applications of a Decision Support System for the integrated model (Rattlesnake Creek subbasin); (2) alternative conceptual models of spatial heterogeneity related to the presence or absence of an underlying aquifer with shallow or deep water table (Lower Republican River basin); and (3) the general nature of the integrated model linkage by employing a watershed simulator other than SWAT (Wet Walnut Creek basin). These applications demonstrate the practicality and versatility of this relatively simple and conceptually clear approach, making public acceptance of the integrated watershed modeling system much easier. This approach also enhances model calibration and thus the reliability of model results. (C) 2000 Elsevier Science B.V.Increased irrigation in Kansas and other regions during the last several decades has caused serious water depletion, making the development of comprehensive strategies and tools to resolve such problems increasingly important. This paper makes the case for an intermediate complexity, quasi-distributed, comprehensive, large-watershed model, which falls between the fully distributed, physically based hydrological modeling system of the type of the SHE model and the lumped, conceptual rainfall-runoff modeling system of the type of the Stanford watershed model. This is achieved by integrating the quasi-distributed watershed model SWAT with the fully-distributed ground-water model MODFLOW. The advantage of this approach is the appreciably smaller input data requirements and the use of readily available data (compared to the fully distributed, physically based models), the statistical handling of watershed heterogeneities by employing the hydrologic-response-unit concept, and the significantly increased flexibility in handling stream-aquifer interactions, distributed well withdrawals, and multiple land uses. The mechanics of integrating the component watershed and ground-water models are outlined, and three real-world management applications of the integrated model from Kansas are briefly presented. Three different aspects of the integrated model are emphasized: (1) management applications of a Decision Support System for the integrated model (Rattlesnake Creek subbasin); (2) alternative conceptual models of spatial heterogeneity related to the presence or absence of an underlying aquifer with shallow or deep water table (Lower Republican River basin); and (3) the general nature of the integrated model linkage by employing a watershed simulator other than SWAT (Wet Walnut Creek basin). These applications demonstrate the practicality and ve

Water insecurity and emotional distress: coping with supply, access, and seasonal variability of water in a Bolivian squatter settlement.

PubMed

Wutich, Amber; Ragsdale, Kathleen

2008-12-01

Recent research suggests that insecure access to key resources is associated with negative mental health outcomes. Many of these studies focus on drought and famine in agricultural, pastoral, and foraging communities, and indicate that food insecurity mediates the link between water insecurity and emotional distress. The present study is the first to systematically examine intra-community patterns of water insecurity in an urban setting. In 2004-2005, we collected interview data from a random sample of 72 household heads in Villa Israel, a squatter settlement of Cochabamba, Bolivia. We examined the extent to which water-related emotional distress is linked with three dimensions of water insecurity: inadequate water supply; insufficient access to water distribution systems; and dependence on seasonal water sources, and with gender. We found that access to water distribution systems and female gender were significantly associated with emotional distress, while water supply and dependence on seasonal water sources were not. Economic assets, social assets, entitlements to water markets, and entitlements to reciprocal exchanges of water were significantly associated with emotional distress, while entitlements to a common-pool water resource institution were not. These results suggest that water-related emotional distress develops as a byproduct of the social and economic negotiations people employ to gain access to water distribution systems in the absence of clear procedures or established water rights rather than as a result of water scarcity per se.

Life cycle analysis of distributed concentrating solar combined heat and power: economics, global warming potential and water

NASA Astrophysics Data System (ADS)

Norwood, Zack; Kammen, Daniel

2012-12-01

We report on life cycle assessment (LCA) of the economics, global warming potential and water (both for desalination and water use in operation) for a distributed concentrating solar combined heat and power (DCS-CHP) system. Detailed simulation of system performance across 1020 sites in the US combined with a sensible cost allocation scheme informs this LCA. We forecast a levelized cost of 0.25 kWh-1 electricity and 0.03 kWh-1 thermal, for a system with a life cycle global warming potential of ˜80 gCO2eq kWh-1 of electricity and ˜10 gCO2eq kWh-1 thermal, sited in Oakland, California. On the basis of the economics shown for air cooling, and the fact that any combined heat and power system reduces the need for cooling while at the same time boosting the overall solar efficiency of the system, DCS-CHP compares favorably to other electric power generation systems in terms of minimization of water use in the maintenance and operation of the plant. The outlook for water desalination coupled with distributed concentrating solar combined heat and power is less favorable. At a projected cost of 1.40 m-3, water desalination with DCS-CHP would be economical and practical only in areas where water is very scarce or moderately expensive, primarily available through the informal sector, and where contaminated or salt water is easily available as feed-water. It is also interesting to note that 0.40-1.90 m-3 is the range of water prices in the developed world, so DCS-CHP desalination systems could also be an economical solution there under some conditions.

Influence of Household Water Filters on Bacteria Growth and Trace Metals in Tap Water of Doha, Qatar.

PubMed

Nriagu, Jerome; Xi, Chuanwu; Siddique, Azhar; Vincent, Annette; Shomar, Basem

2018-05-29

Deteriorating water quality from aging infrastructure, growing threat of pollution from industrialization and urbanization, and increasing awareness about waterborne diseases are among the factors driving the surge in worldwide use of point-of-entry (POE) and point-of-use (POU) filters. Any adverse influence of such consumer point-of-use systems on quality of water at the tap remains poorly understood, however. We determined the chemical and microbiological changes in municipal water from the point of entry into the household plumbing system until it leaves from the tap in houses equipped with filters. We show that POE/POU devices can induce significant deterioration of the quality of tap water by functioning as traps and reservoirs for sludge, scale, rust, algae or slime deposits which promote microbial growth and biofilm formation in the household water distribution system. With changes in water pressure and physical or chemical disturbance of the plumbing system, the microorganisms and contaminants may be flushed into the tap water. Such changes in quality of household water carry a potential health risk which calls for some introspection in widespread deployment of POE/POU filters in water distribution systems.

Site-specific variable rate irrigation a means to enhance water use efficiency

USDA-ARS?s Scientific Manuscript database

The majority of irrigated cropland in the US is watered with sprinkler irrigation systems. These systems are inherently more efficient in distributing water than furrow or flood irrigation. Appropriate system design of sprinkler irrigation equipment, application methods, and farming practices (e.g. ...

Site-specific variable rate irrigation as a means to enhance water use efficiency

USDA-ARS?s Scientific Manuscript database

The majority of irrigated cropland in the US is watered with sprinkler irrigation systems. These systems are inherently more efficient in distributing water than furrow or flood irrigation. Appropriate system design of sprinkler irrigation equipment, application methods, and farming practices (e.g. ...

CREATION OF A MULTIDISCIPLINARY PROJECT PLATFORM FOR WATER SYSTEMS IN DEVELOPING COUNTRIES

EPA Science Inventory

The Lehigh University chapter of Engineers Without Borders-USA will design and construct a sustainable, multi-phase system for the treatment and distribution of drinking water in Pueblo Nuevo, Honduras. The new system will include a slow sand filter, hypochlorinator, water sto...

Dynamics of bacterial communities before and after distribution in a full-scale drinking water network.

PubMed

El-Chakhtoura, Joline; Prest, Emmanuelle; Saikaly, Pascal; van Loosdrecht, Mark; Hammes, Frederik; Vrouwenvelder, Hans

2015-05-01

Understanding the biological stability of drinking water distribution systems is imperative in the framework of process control and risk management. The objective of this research was to examine the dynamics of the bacterial community during drinking water distribution at high temporal resolution. Water samples (156 in total) were collected over short time-scales (minutes/hours/days) from the outlet of a treatment plant and a location in its corresponding distribution network. The drinking water is treated by biofiltration and disinfectant residuals are absent during distribution. The community was analyzed by 16S rRNA gene pyrosequencing and flow cytometry as well as conventional, culture-based methods. Despite a random dramatic event (detected with pyrosequencing and flow cytometry but not with plate counts), the bacterial community profile at the two locations did not vary significantly over time. A diverse core microbiome was shared between the two locations (58-65% of the taxa and 86-91% of the sequences) and found to be dependent on the treatment strategy. The bacterial community structure changed during distribution, with greater richness detected in the network and phyla such as Acidobacteria and Gemmatimonadetes becoming abundant. The rare taxa displayed the highest dynamicity, causing the major change during water distribution. This change did not have hygienic implications and is contingent on the sensitivity of the applied methods. The concept of biological stability therefore needs to be revised. Biostability is generally desired in drinking water guidelines but may be difficult to achieve in large-scale complex distribution systems that are inherently dynamic. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ground-water movement and nitrate in ground water, East Erda area, Tooele County, Utah, 1997-2000

USGS Publications Warehouse

Susong, D.D.

2005-01-01

Nitrate was discovered in ground water in the east Erda area of Tooele County, Utah, in 1994. The U.S. Geological Survey, in cooperation with Tooele County, investigated the ground-water flow system and water quality in the eastern part of Tooele Valley to determine (1) the vertical and horizontal distribution of nitrate, (2) the direction of movement of the nitrate contamination, and (3) the source of the nitrate. The potentiometric surface of the upper part of the basin-fill aquifer indicates that the general direction of ground-water flow is to the northwest, the flow system is complex, and there is a ground-water mound probably associated with springs. The spatial distribution of nitrate reflects the flow system with the nitrate contamination split into a north and south part by the ground-water mound. The distribution of dissolved solids and sulfate in ground water varies spatially. Vertical profiles of nitrate in water from selected wells indicate that nitrate contamination generally is in the upper part of the saturated zone and in some wells has moved downward. Septic systems, mining and smelting, agriculture, and natural sources were considered to be possible sources of nitrate contamination in the east Erda area. Septic systems are not the source of nitrate because water from wells drilled upgradient of all septic systems in the area had elevated nitrate concentrations. Mining and smelting activity are a possible source of nitrate contamination but few data are available to link nitrate contamination with mining sites. Natural and agricultural sources of nitrate are present east of the Erda area but few data are available about these sources. The source(s) of nitrate in the east Erda area could not be clearly delineated in spite of considerable effort and expenditure of resources.

Transformation rules and degradation of CAHs by Fentonlike oxidation in growth ring of water distribution network-A review

NASA Astrophysics Data System (ADS)

Zhong, D.; Ma, W. C.; Jiang, X. Q.; Yuan, Y. X.; Yuan, Y.; Wang, Z. Q.; Fang, T. T.; Huang, W. Y.

2017-08-01

Chlorinated hydrocarbons are widely used as organic solvent and chemical raw materials. After treatment, water polluted with trichloroethylene (TCE)/tetrachloroethylene (PCE) can reach the water quality requirements, while water with trace amounts of TCE/PCE is still harmful to humans, which will cause cancers. Water distribution network is an extremely complicated system, in which adsorption, desorption, flocculation, movement, transformation and reduction will occur, leading to changes of TCE/PCE concentrations and products. Therefore, it is important to investigate the transformation rules of TCE/PCE in water distribution network. What’s more, growth-ring, including drinking water pipes deposits, can act as catalysts in Fenton-like reagent (H2O2). This review summarizes the status of transformation rules of CAHs in water distribution network. It also evaluates the effectiveness and fruit of CAHs degradation by Fenton-like reagent based on growth-ring. This review is important in solving the potential safety problems caused by TCE/PCE in water distribution network.

USING CONTINUOUS MONITORS FOR CONDUCTING TRACER STUDIES IN WATER DISTRIBUTION SYSTEMS

EPA Science Inventory

The use of online monitors for conducting a distribution system tracer study is proving to be an essential tool to accurately understand the flow dynamics in a distribution system. In a series of field testing sponsored by U. S. Environmental Protection Agency (EPA) and Greater ...

Effect of temperature and pH on dehalogenation of total organic chlorine, bromine and iodine in drinking water.

PubMed

Abusallout, Ibrahim; Rahman, Shamimur; Hua, Guanghui

2017-11-01

Disinfection byproduct (DBP) concentrations in drinking water distribution systems and indoor water uses depend on competitive formation and degradation reactions. This study investigated the dehalogenation kinetics of total organic chlorine (TOCl), bromine (TOBr) and iodine (TOI) produced by fulvic acid under different pH and temperature conditions, and total organic halogen (TOX) variations in a treated drinking water under simulated distribution system and heating scenarios. TOX dehalogenation rates were generally in the order of TOI ≅ TOCl(NH 2 Cl) > TOBr > TOCl(Cl 2 ). The half-lives of different groups of TOX compounds formed by fulvic acid varied between 27 and 139 days during incubation at 20 °C and 0.98-2.17 days during heating at 55 °C. Base-catalyzed reactions played a major role in TOX degradation as evidenced by enhanced dehalogenation under high pH conditions. The results of heating of a treated water in the presence of residuals showed that TOX concentrations of chlorinated samples increased rapidly when chlorine residuals were present and then gradually decreased after chlorine residuals were exhausted. The final TOX concentrations of chlorinated samples after heating showed moderate decreases with increasing ambient water ages. Chloraminated samples with different ambient water ages exhibited similar final TOX concentrations during simulated distribution system and heating experiments. This study reinforces the importance of understanding DBP variations in indoor water uses as wells as in distribution systems to provide more accurate DBP information for exposure assessment and regulatory determination. Published by Elsevier Ltd.

Lead in ancient Rome's city waters.

PubMed

Delile, Hugo; Blichert-Toft, Janne; Goiran, Jean-Philippe; Keay, Simon; Albarède, Francis

2014-05-06

It is now universally accepted that utilization of lead for domestic purposes and water distribution presents a major health hazard. The ancient Roman world was unaware of these risks. How far the gigantic network of lead pipes used in ancient Rome compromised public health in the city is unknown. Lead isotopes in sediments from the harbor of Imperial Rome register the presence of a strong anthropogenic component during the beginning of the Common Era and the Early Middle Ages. They demonstrate that the lead pipes of the water distribution system increased Pb contents in drinking water of the capital city by up to two orders of magnitude over the natural background. The Pb isotope record shows that the discontinuities in the pollution of the Tiber by lead are intimately entwined with the major issues affecting Late Antique Rome and its water distribution system.

Long-Term Bacterial Dynamics in a Full-Scale Drinking Water Distribution System

PubMed Central

Prest, E. I.; Weissbrodt, D. G.; Hammes, F.; van Loosdrecht, M. C. M.; Vrouwenvelder, J. S.

2016-01-01

Large seasonal variations in microbial drinking water quality can occur in distribution networks, but are often not taken into account when evaluating results from short-term water sampling campaigns. Temporal dynamics in bacterial community characteristics were investigated during a two-year drinking water monitoring campaign in a full-scale distribution system operating without detectable disinfectant residual. A total of 368 water samples were collected on a biweekly basis at the water treatment plant (WTP) effluent and at one fixed location in the drinking water distribution network (NET). The samples were analysed for heterotrophic plate counts (HPC), Aeromonas plate counts, adenosine-tri-phosphate (ATP) concentrations, and flow cytometric (FCM) total and intact cell counts (TCC, ICC), water temperature, pH, conductivity, total organic carbon (TOC) and assimilable organic carbon (AOC). Multivariate analysis of the large dataset was performed to explore correlative trends between microbial and environmental parameters. The WTP effluent displayed considerable seasonal variations in TCC (from 90 × 103 cells mL-1 in winter time up to 455 × 103 cells mL-1 in summer time) and in bacterial ATP concentrations (<1–3.6 ng L-1), which were congruent with water temperature variations. These fluctuations were not detected with HPC and Aeromonas counts. The water in the network was predominantly influenced by the characteristics of the WTP effluent. The increase in ICC between the WTP effluent and the network sampling location was small (34 × 103 cells mL-1 on average) compared to seasonal fluctuations in ICC in the WTP effluent. Interestingly, the extent of bacterial growth in the NET was inversely correlated to AOC concentrations in the WTP effluent (Pearson’s correlation factor r = -0.35), and positively correlated with water temperature (r = 0.49). Collecting a large dataset at high frequency over a two year period enabled the characterization of previously undocumented seasonal dynamics in the distribution network. Moreover, high-resolution FCM data enabled prediction of bacterial cell concentrations at specific water temperatures and time of year. The study highlights the need to systematically assess temporal fluctuations in parallel to spatial dynamics for individual drinking water distribution systems. PMID:27792739

Long-Term Bacterial Dynamics in a Full-Scale Drinking Water Distribution System.

PubMed

Prest, E I; Weissbrodt, D G; Hammes, F; van Loosdrecht, M C M; Vrouwenvelder, J S

2016-01-01

Large seasonal variations in microbial drinking water quality can occur in distribution networks, but are often not taken into account when evaluating results from short-term water sampling campaigns. Temporal dynamics in bacterial community characteristics were investigated during a two-year drinking water monitoring campaign in a full-scale distribution system operating without detectable disinfectant residual. A total of 368 water samples were collected on a biweekly basis at the water treatment plant (WTP) effluent and at one fixed location in the drinking water distribution network (NET). The samples were analysed for heterotrophic plate counts (HPC), Aeromonas plate counts, adenosine-tri-phosphate (ATP) concentrations, and flow cytometric (FCM) total and intact cell counts (TCC, ICC), water temperature, pH, conductivity, total organic carbon (TOC) and assimilable organic carbon (AOC). Multivariate analysis of the large dataset was performed to explore correlative trends between microbial and environmental parameters. The WTP effluent displayed considerable seasonal variations in TCC (from 90 × 103 cells mL-1 in winter time up to 455 × 103 cells mL-1 in summer time) and in bacterial ATP concentrations (<1-3.6 ng L-1), which were congruent with water temperature variations. These fluctuations were not detected with HPC and Aeromonas counts. The water in the network was predominantly influenced by the characteristics of the WTP effluent. The increase in ICC between the WTP effluent and the network sampling location was small (34 × 103 cells mL-1 on average) compared to seasonal fluctuations in ICC in the WTP effluent. Interestingly, the extent of bacterial growth in the NET was inversely correlated to AOC concentrations in the WTP effluent (Pearson's correlation factor r = -0.35), and positively correlated with water temperature (r = 0.49). Collecting a large dataset at high frequency over a two year period enabled the characterization of previously undocumented seasonal dynamics in the distribution network. Moreover, high-resolution FCM data enabled prediction of bacterial cell concentrations at specific water temperatures and time of year. The study highlights the need to systematically assess temporal fluctuations in parallel to spatial dynamics for individual drinking water distribution systems.

MICROBIAL CHARACTERIZATION OF DRINKING WATER SYSTEMS RECEIVING GROUNDWATER AND SURFACE WATER AS THE PRIMARY SOURCES OF WATER

EPA Science Inventory

Earlier descriptions of water distribution systems (WDS) microbial communities have relied on culturing techniques. These techniques are known to be highly selective in nature, but more importantly, they tend to grossly underestimate the microbial diversity of most environments. ...

Optimal Dynamics of Intermittent Water Supply

NASA Astrophysics Data System (ADS)

Lieb, Anna; Wilkening, Jon; Rycroft, Chris

2014-11-01

In many urban areas of the developing world, piped water is supplied only intermittently, as valves direct water to different parts of the water distribution system at different times. The flow is transient, and may transition between free-surface and pressurized, resulting in complex dynamical features with important consequences for water suppliers and users. These consequences include degradation of distribution system components, compromised water quality, and inequitable water availability. The goal of this work is to model the important dynamics and identify operating conditions that mitigate certain negative effects of intermittent water supply. Specifically, we will look at valve parameters occurring as boundary conditions in a network model of transient, transition flow through closed pipes. Optimization will be used to find boundary values to minimize pressure gradients and ensure equitable water availability.

Principles for scaling of distributed direct potable water reuse systems: a modeling study.

PubMed

Guo, Tianjiao; Englehardt, James D

2015-05-15

Scaling of direct potable water reuse (DPR) systems involves tradeoffs of treatment facility economy-of-scale, versus cost and energy of conveyance including energy for upgradient distribution of treated water, and retention of wastewater thermal energy. In this study, a generalized model of the cost of DPR as a function of treatment plant scale, assuming futuristic, optimized conveyance networks, was constructed for purposes of developing design principles. Fractal landscapes representing flat, hilly, and mountainous topographies were simulated, with urban, suburban, and rural housing distributions placed by modified preferential growth algorithm. Treatment plants were allocated by agglomerative hierarchical clustering, networked to buildings by minimum spanning tree. Simulations assume advanced oxidation-based DPR system design, with 20-year design life and capability to mineralize chemical oxygen demand below normal detection limits, allowing implementation in regions where disposal of concentrate containing hormones and antiscalants is not practical. Results indicate that total DPR capital and O&M costs in rural areas, where systems that return nutrients to the land may be more appropriate, are high. However, costs in urban/suburban areas are competitive with current water/wastewater service costs at scales of ca. one plant per 10,000 residences. This size is relatively small, and costs do not increase significantly until plant service areas fall below 100 to 1000 homes. Based on these results, distributed DPR systems are recommended for consideration for urban/suburban water and wastewater system capacity expansion projects. Copyright © 2015 Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Costa, Mafalda T., E-mail: mafaldatcosta@gmail.com; Carolino, Elisabete, E-mail: lizcarolino@gmail.com; Oliveira, Teresa A., E-mail: teresa.oliveira@uab.pt

In water supply systems with distribution networkthe most critical aspects of control and Monitoring of water quality, which generates crises system, are the effects of cross-contamination originated by the network typology. The classics of control of quality systems through the application of Shewhart charts are generally difficult to manage in real time due to the high number of charts that must be completed and evaluated. As an alternative to the traditional control systems with Shewhart charts, this study aimed to apply a simplified methodology of a monitoring plan quality parameters in a drinking water distribution, by applying Hotelling’s T{sup 2}more » charts and supplemented with Shewhart charts with Bonferroni limits system, whenever instabilities with processes were detected.« less

Effect of sulfate on the transformation of corrosion scale composition and bacterial community in cast iron water distribution pipes

EPA Science Inventory

The stability of iron corrosion products and the bacterial composition of biofilm in drinking water distribution systems (DWDS) could have great impact on the water safety at the consumer ends. In this work, pipe loops were setup to investigate the transformation characteristics ...

Release of accumulated arsenic from distribution pipes into tap water after arsenic treatment of source water- presentation

EPA Science Inventory

Toxic arsenic (As) is known to incorporate from source well water onto the scales of distribution system pipes such as iron, copper, galvanized steel and even plastic containing internal buildup of iron coatings (Lytle et al., 2010, 2004; Schock, 2015; Reiber and Dostal, 2000). W...

Detection of contamination of municipal water distribution systems

DOEpatents

Cooper, John F [Oakland, CA

2012-01-17

A system for the detection of contaminates of a fluid in a conduit. The conduit is part of a fluid distribution system. A chemical or biological sensor array is connected to the conduit. The sensor array produces an acoustic signal burst in the fluid upon detection of contaminates in the fluid. A supervisory control system connected to the fluid and operatively connected to the fluid distribution system signals the fluid distribution system upon detection of contaminates in the fluid.

Monitoring copper release in drinking water distribution systems.

PubMed

d'Antonio, L; Fabbricino, M; Panico, A

2008-01-01

A new procedure, recently proposed for on-line monitoring of copper released from metal pipes in household plumbing system for drinking water distribution during the development of corrosion processes, is tested experimentally. Experiments were carried out in laboratory controlled conditions, using synthetic water and varying the water alkalinity. The possibility of using the corrosion potential as a surrogate measure of copper concentration in stagnating water is shown, verifying, in the meantime, the effect of alkalinity on the development of passivation phenomena, which tend to protect the pipe from corrosion processes. Experimental data are discussed, highlighting the potentiality of the procedure, and recognizing its limitations. Copyright IWA Publishing 2008.

Household Water Systems: Tailoring Treatment Alternatives to Contaminants in Groundwater and Distribution Systems

EPA Science Inventory

This SSWR Webinar will provide an overview of ORD point-of-use/point-of entry research studies. The presentation will document the applicability of POU/POE devices and the regulatory requirements for household water systems under the Safe Drinking Water Act. The presentation wi...

RISK ASSESSMENT AND MANAGEMENT OF WATER SUPPLY SYSTEM - INFRASTRUCTURE INITIATIVE FOR THE 21ST CENTURY

EPA Science Inventory

The current problem in the United States is that the water infrastructure is aging and spending has not been adequate to repair, replace, or rehabilitate drinking water distribution systems and wastewater collection systems. The American Society of Civil Engineers Report Card in...

Advanced Hydraulics for Operators. Training Module 1.331.3.77.

ERIC Educational Resources Information Center

Bengston, Harlan H.

This document is an instructional module package prepared in objective form for use by an instructor familiar with the application of hydraulic principles to water supply and water pollution control systems including water distribution systems and sewer systems. Included are objectives, instructor guides, student handouts and transparency masters.…

Partition of nonionic organic compounds in aquatic systems

USGS Publications Warehouse

Smith, James A.; Witkowski, Patrick J.; Chiou, Cary T.

1988-01-01

In aqueous systems, the distribution of many nonionic organic solutes in soil-sediment, aquatic organisms, and dissolved organic matter can be explained in terms of a partition model. The nonionic organic solute is distributed between water and different organic phases that behave as bulk solvents. Factors such as polarity, composition, and molecular size of the solute and organic phase determine the relative importance of partition to the environmental distribution of the solute. This chapter reviews these factors in the context of a partition model and also examines several environmental applications of the partition model for surface- and ground-water systems.

Environmental Control and Life Support System

NASA Technical Reports Server (NTRS)

Ray, Charles; Adams, Alan

1990-01-01

Viewgraphs on the Environmental Control and Life Support System (ECLSS) for the space station are presented. The ECLSS is divided into six subsystems: temperature and humidity control (THC), atmosphere control and supply (ACS), atmosphere revitalization (AR), fire detection and suppression (FDS), water recovery management (WRM), and waste management (WM). Topics covered include: ECLSS subsystem functions; ECLSS distributed system; ECLSS functional distribution; CO2 removal; CO2 reduction; oxygen generation; urine processor; and potable water recovery.

Channel-Island Connectivity Affects Water Exposure Time Distributions in a Coastal River Delta

NASA Astrophysics Data System (ADS)

Hiatt, Matthew; Castañeda-Moya, Edward; Twilley, Robert; Hodges, Ben R.; Passalacqua, Paola

2018-03-01

The exposure time is a water transport time scale defined as the cumulative amount of time a water parcel spends in the domain of interest regardless of the number of excursions from the domain. Transport time scales are often used to characterize the nutrient removal potential of aquatic systems, but exposure time distribution estimates are scarce for deltaic systems. Here we analyze the controls on exposure time distributions using a hydrodynamic model in two domains: the Wax Lake delta in Louisiana, USA, and an idealized channel-island complex. In particular, we study the effects of river discharge, vegetation, network geometry, and tides and use a simple model for the fractional removal of nitrate. In both domains, we find that channel-island hydrological connectivity significantly affects exposure time distributions and nitrate removal. The relative contributions of the island and channel portions of the delta to the overall exposure time distribution are controlled by island vegetation roughness and network geometry. Tides have a limited effect on the system's exposure time distribution but can introduce significant spatial variability in local exposure times. The median exposure time for the WLD model is 10 h under the conditions tested and water transport within the islands contributes to 37-50% of the network-scale exposure time distribution and 52-73% of the modeled nitrate removal, indicating that islands may account for the majority of nitrate removal in river deltas.

Catalytic Enzyme-Based Methods for Water Treatment and Water Distribution System Decontamination. 1. Literature Survey

DTIC Science & Technology

2006-06-01

TREATMENT AND WATER DISTRIBUTION SYSTEM DECONTAMINATION 1 . LITERATURE SURVEY Joseph J. DeFrank RESEARCH AND TECHNOLOGY DIRECTORATE June 2006 Approved for...No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing...YOUR FORM TO THE ABOVE ADDRESS. 1 . REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE 3. DATES COVERED (From - To) XX-06-2006 Literature Survey May 2004 - Aug 2004

CHARACTERIZATION OF SUB-MICRON AQUEOUS IRON(III) COLLOIDS FORMED IN THE PRESENCE OF PHOSPHATE BY SEDIMENTATION FIELD FLOW FRACTIONATION WITH MULTI-ANGLE LASER LIGHT SCATTERING DETECTION

EPA Science Inventory

Iron colloids play a major role in the water chemistry of natural watersheds and of engineered drinking water distribution systems. Phosphate is frequently added to distribution systems to control corrosion problems, so iron-phosphate colloids may form through reaction of iron in...

Review on water leakage control in distribution networks and the associated environmental benefits.

PubMed

Xu, Qiang; Liu, Ruiping; Chen, Qiuwen; Li, Ruonan

2014-05-01

Water supply is the primary element of an urban system. Due to rapid urbanization and water scarcity, maintaining a stable and safe water supply has become a challenge to many cities, whereas a large amount of water is lost from the pipes of distribution systems. Water leakage is not only a waste of water resources, but also incurs great socio-economic costs. This article presents a comprehensive review on the potential water leakage control approaches and specifically discusses the benefits of each to environmental conservation. It is concluded that water leakage could be further reduced by improving leakage detection capability through a combination of predictive modeling and monitoring instruments, optimizing pipe maintenance strategy, and developing an instant pressure regulation system. The environment could benefit from these actions because of water savings and the reduction of energy consumption as well as greenhouse gas emissions. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Effect of PVC and iron materials on Mn(II) deposition in drinking water distribution systems.

PubMed

Cerrato, José M; Reyes, Lourdes P; Alvarado, Carmen N; Dietrich, Andrea M

2006-08-01

Polyvinyl chloride (PVC) and iron pipe materials differentially impacted manganese deposition within a drinking water distribution system that experiences black water problems because it receives soluble manganese from a surface water reservoir that undergoes biogeochemical cycling of manganese. The water quality study was conducted in a section of the distribution system of Tegucigalpa, Honduras and evaluated the influence of iron and PVC pipe materials on the concentrations of soluble and particulate iron and manganese, and determined the composition of scales formed on PVC and iron pipes. As expected, total Fe concentrations were highest in water from iron pipes. Water samples obtained from PVC pipes showed higher total Mn concentrations and more black color than that obtained from iron pipes. Scanning electron microscopy demonstrated that manganese was incorporated into the iron tubercles and thus not readily dislodged from the pipes by water flow. The PVC pipes contained a thin surface scale consisting of white and brown layers of different chemical composition; the brown layer was in contact with the water and contained 6% manganese by weight. Mn composed a greater percentage by weight of the PVC scale than the iron pipe scale; the PVC scale was easily dislodged by flowing water. This research demonstrates that interactions between water and the infrastructure used for its supply affect the quality of the final drinking water.

Defense Management: Further Analysis Needed to Identify Guam’s Public Infrastructure Requirements and Costs for DOD’s Realignment Plan

DTIC Science & Technology

2013-12-01

Safe Drinking Water Act28 and the Clean Water Act.29 • Potable water : According to Waterworks officials, Guam’s potable water system currently is in...noncompliance with the Safe Drinking Water Act. The unreliable drinking water distribution system has historically resulted in bacterial...Protection Consolidated Grants program, provided Guam with almost $6.8 million in fiscal year 2012 to fund drinking water and wastewater system

Chilled water study EEAP program for Walter Reed Army Medical Center: Book 2. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-02-01

The Energy Engineering Analysis Program (EEAP) Study for Walter Reed Army Medical Center (WRAMC) was to provide a thorough examination of the central chilled water plants on site. WRAMC is comprised of seventy-one (71) buildings located on a 113-acre site in Washington, D.C. There are two (2) central chilled water plants (Buildings 48 and 49) each with a primary chilled water distribution system. In addition to the two (2) central plants, three (3) buildings utilize their own independent chillers. Two (2) of the independent chillers (Buildings 7 and T-2), one of which is inoperative (T-2), are smaller air-cooled units, whilemore » the third (Building 54) has a 1,900-ton chilled water plant comprised of three (3) centrifugal chillers. Of the two (2) central chilled water plants, Building 48 houses six (6) chillers totalling 7,080 tons of cooling and Building 49 houses one (1) chiller with 660 tons of cooling. The total chiller cooling capacity available on site is 9,840 tons. The chilled water systems were reviewed for alternative ways of conserving energy on site and reducing the peak-cooling load. Distribution systems were reviewed to determine which buildings were served by each of the chilled water plants and to determine chilled water usage on site. Evaluations were made of building exterior and interior composition in order to estimate cooling loads. Interviews with site personnel helped Entech better understand the chilled water plants, the distribution systems, and how each system was utilized.« less

ADAPTIVE MONITORING TO ENHANCE WATER SENSOR CAPABILITIES FOR CHEMICAL AND BIOLOGICAL CONTAMINANT DETECTION IN DRINKING WATER SYSTEMS

EPA Science Inventory

Optoelectronic and other conventional water quality sensors offer a potential for real-time online detection of chemical and biological contaminants in a drinking water supply and distribution system. The nature of the application requires sensors of detection capabilities at lo...

Development of a system dynamics model for financially sustainable management of municipal watermain networks.

PubMed

Rehan, R; Knight, M A; Unger, A J A; Haas, C T

2013-12-15

This paper develops causal loop diagrams and a system dynamics model for financially sustainable management of urban water distribution networks. The developed causal loop diagrams are a novel contribution in that it illustrates the unique characteristics and feedback loops for financially self-sustaining water distribution networks. The system dynamics model is a mathematical realization of the developed interactions among system variables over time and is comprised of three sectors namely watermains network, consumer, and finance. This is the first known development of a water distribution network system dynamics model. The watermains network sector accounts for the unique characteristics of watermain pipes such as service life, deterioration progression, pipe breaks, and water leakage. The finance sector allows for cash reserving by the utility in addition to the pay-as-you-go and borrowing strategies. The consumer sector includes controls to model water fee growth as a function of service performance and a household's financial burden due to water fees. A series of policy levers are provided that allow the impact of various financing strategies to be evaluated in terms of financial sustainability and household affordability. The model also allows for examination of the impact of different management strategies on the water fee in terms of consistency and stability over time. The paper concludes with a discussion on how the developed system dynamics water model can be used by water utilities to achieve a variety of utility short and long-term objectives and to establish realistic and defensible water utility policies. It also discusses how the model can be used by regulatory bodies, government agencies, the financial industry, and researchers. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Risk of waterborne illness via drinking water in the United States.

PubMed

Reynolds, Kelly A; Mena, Kristina D; Gerba, Charles P

2008-01-01

Outbreaks of disease attributable to drinking water are not common in the U.S., but they do still occur and can lead to serious acute, chronic, or sometimes fatal health consequences, particularly in sensitive and immunocompromised populations. From 1971 to 2002, there were 764 documented waterborne outbreaks associated with drinking water, resulting in 575,457 cases of illness and 79 deaths (Blackburn et al. 2004; Calderon 2004); however, the true impact of disease is estimated to be much higher. If properly applied, current protocols in municipal water treatment are effective at eliminating pathogens from water. However, inadequate, interrupted, or intermittent treatment has repeatedly been associated with waterborne disease outbreaks. Contamination is not evenly distributed but rather affected by the number of pathogens in the source water, the age of the distribution system, the quality of the delivered water, and climatic events that can tax treatment plant operations. Private water supplies are not regulated by the USEPA and are generally not treated or monitored, although very few of the municipal systems involved in documented outbreaks exceeded the USEPA's total coliform standard in the preceding 12 mon (Craun et al. 2002). We provide here estimates of waterborne infection and illness risks in the U.S. based on the total number of water systems, source water type, and total populations exposed. Furthermore, we evaluated all possible illnesses associated with the microbial infection and not just gastroenteritis. Our results indicate that 10.7 M infections/yr and 5.4 M illnesses/yr occur in populations served by community groundwater systems; 2.2 M infections/yr and 1.1 M illnesses/yr occur in noncommunity groundwater systems; and 26.0 M infections/yr and 13.0 M illnesses/yr occur in municipal surface water systems. The total estimated number of waterborne illnesses/yr in the U.S. is therefore estimated to be 19.5 M/yr. Others have recently estimated waterborne illness rates of 12M cases/yr (Colford et al. 2006) and 16 M cases/yr (Messner et al. 2006), yet our estimate considers all health outcomes associated with exposure to pathogens in drinking water rather than only gastrointestinal illness. Drinking water outbreaks exemplify known breaches in municipal water treatment and distribution processes and the failure of regulatory requirements to ensure water that is free of human pathogens. Water purification technologies applied at the point-of-use (POU) can be effective for limiting the effects of source water contamination, treatment plant inadequacies, minor intrusions in the distribution system, or deliberate posttreatment acts (i.e., bioterrorism). Epidemiological studies are conflicting on the benefits of POU water treatment. One prospective intervention study found that consumers of reverse-osmosis (POU) filtered water had 20%-35% less gastrointestinal illnesses than those consuming regular tap water, with an excess of 14% of illness due to contaminants introduced in the distribution system (Payment 1991, 1997). Two other studies using randomized, blinded, controlled trials determined that the risks were equal among groups supplied with POU-treated water compared to untreated tap water (Hellard et al. 2001; Colford et al. 2003). For immunocompromised populations, POU water treatment devices are recommended by the CDC and USEPA as one treatment option for reducing risks of Cryptosporidium and other types of infectious agents transmitted by drinking water. Other populations, including those experiencing "normal" life stages such as pregnancy, or those very young or very old, might also benefit from the utilization of additional water treatment options beyond the current multibarrier approach of municipal water treatment.

Network Capacity Assessment of CHP-based Distributed Generation on Urban Energy Distribution Networks

NASA Astrophysics Data System (ADS)

Zhang, Xianjun

The combined heat and power (CHP)-based distributed generation (DG) or dis-tributed energy resources (DERs) are mature options available in the present energy market, considered to be an effective solution to promote energy efficiency. In the urban environment, the electricity, water and natural gas distribution networks are becoming increasingly interconnected with the growing penetration of the CHP-based DG. Subsequently, this emerging interdependence leads to new topics meriting serious consideration: how much of the CHP-based DG can be accommodated and where to locate these DERs, and given preexisting constraints, how to quantify the mutual impacts on operation performances between these urban energy distribution networks and the CHP-based DG. The early research work was conducted to investigate the feasibility and design methods for one residential microgrid system based on existing electricity, water and gas infrastructures of a residential community, mainly focusing on the economic planning. However, this proposed design method cannot determine the optimal DG sizing and siting for a larger test bed with the given information of energy infrastructures. In this context, a more systematic as well as generalized approach should be developed to solve these problems. In the later study, the model architecture that integrates urban electricity, water and gas distribution networks, and the CHP-based DG system was developed. The proposed approach addressed the challenge of identifying the optimal sizing and siting of the CHP-based DG on these urban energy networks and the mutual impacts on operation performances were also quantified. For this study, the overall objective is to maximize the electrical output and recovered thermal output of the CHP-based DG units. The electricity, gas, and water system models were developed individually and coupled by the developed CHP-based DG system model. The resultant integrated system model is used to constrain the DG's electrical output and recovered thermal output, which are affected by multiple factors and thus analyzed in different case studies. The results indicate that the designed typical gas system is capable of supplying sufficient natural gas for the DG normal operation, while the present water system cannot support the complete recovery of the exhaust heat from the DG units.

Disaggregating Hot Water Use and Predicting Hot Water Waste in Five Test Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henderson, H.; Wade, J.

2014-04-01

While it is important to make the equipment (or 'plant') in a residential hot water system more efficient, the hot water distribution system also affects overall system performance and energy use. Energy wasted in heating water that is not used is estimated to be on the order of 10 to 30 percent of total domestic hot water (DHW) energy use. This field monitoring project installed temperature sensors on the distribution piping (on trunks and near fixtures) and programmed a data logger to collect data at 5 second intervals whenever there was a hot water draw. This data was used tomore » assign hot water draws to specific end uses in the home as well as to determine the portion of each hot water that was deemed useful (i.e., above a temperature threshold at the fixture). Five houses near Syracuse NY were monitored. Overall, the procedures to assign water draws to each end use were able to successfully assign about 50% of the water draws, but these assigned draws accounted for about 95% of the total hot water use in each home. The amount of hot water deemed as useful ranged from low of 75% at one house to a high of 91% in another. At three of the houses, new water heaters and distribution improvements were implemented during the monitoring period and the impact of these improvements on hot water use and delivery efficiency were evaluated.« less

Disaggregating Hot Water Use and Predicting Hot Water Waste in Five Test Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henderson, Hugh; Wade, Jeremy

2014-04-01

While it is important to make the equipment (or "plant") in a residential hot water system more efficient, the hot water distribution system also affects overall system performance and energy use. Energy wasted in heating water that is not used is estimated to be on the order of 10%-30% of total domestic hot water (DHW) energy use. This field monitoring project installed temperature sensors on the distribution piping (on trunks and near fixtures) in five houses near Syracuse, NY, and programmed a data logger to collect data at 5 second intervals whenever there was a hot water draw. This datamore » was used to assign hot water draws to specific end uses in the home as well as to determine the portion of each hot water that was deemed useful (i.e., above a temperature threshold at the fixture). Overall, the procedures to assign water draws to each end use were able to successfully assign about 50% of the water draws, but these assigned draws accounted for about 95% of the total hot water use in each home. The amount of hot water deemed as useful ranged from low of 75% at one house to a high of 91% in another. At three of the houses, new water heaters and distribution improvements were implemented during the monitoring period and the impact of these improvements on hot water use and delivery efficiency were evaluated.« less

OVERVIEW OF USEPA'S WATER SUPPLY & WATER RESOURCES DIVISION PROGRAM

EPA Science Inventory

The United States Environmental Protection Agency's (USEPA) Water Supply and Water Resources Division (WSWRD) conducts a wide range of research on regulated and unregulated contaminants in drinking water, water distribution systems, homeland security, source water protection, and...

Reduction of water losses by rehabilitation of water distribution network.

PubMed

Güngör, Mahmud; Yarar, Ufuk; Firat, Mahmut

2017-09-11

Physical or real losses may be indicated as the most important component of the water losses occurring in a water distribution network (WDN). The objective of this study is to examine the effects of piping material management and network rehabilitation on the physical water losses and water losses management in a WDN. For this aim, the Denizli WDN consisting of very old pipes that have exhausted their economic life is selected as the study area. The fact that the current network is old results in the decrease of pressure strength, increase of failure intensity, and inefficient use of water resources thus leading to the application of the rehabilitation program. In Denizli, network renewal works have been carried out since the year 2009 under the rehabilitation program. It was determined that the failure rate at regions where network renewal constructions have been completed decreased down to zero level. Renewal of piping material enables the minimization of leakage losses as well as the failure rate. On the other hand, the system rehabilitation has the potential to amortize itself in a very short amount of time if the initial investment cost of network renewal is considered along with the operating costs of the old and new systems, as well as water loss costs. As a result, it can be stated that renewal of piping material in water distribution systems, enhancement of the physical properties of the system, provide significant contributions such as increase of water and energy efficiency and more effective use of resources.

Water in embedded low-mass protostars: cold envelopes and warm outflows

NASA Astrophysics Data System (ADS)

Kristensen, Lars E.; van Dishoeck, Ewine; Mottram, Joseph; Schmalzl, Markus; Visser, Ruud

2015-08-01

As stars form, gas from the parental cloud is transported through the molecular envelope to the protostellar disk from which planets eventually form. Water plays a crucial role in such systems: it forms the backbone of the oxygen chemistry, it is a unique probe of warm and hot gas, and it provides a unique link between the grain surface and gas-phase chemistries. The distribution of water, both as ice and gas, is a fundamental question to our understanding of how planetary systems, such as the Solar System, form.The Herschel Space Observatory observed many tens of embedded low-mass protostars in a suite of gas-phase water transitions in several programs (e.g. Water in Star-forming regions with Herschel, WISH, and the William Herschel Line Legacy Survey, WILL), and related species (e.g. CO in Protostars with HIFI, COPS-HIFI). I will summarize what Herschel has revealed about the water distribution in the cold outer molecular envelope of low-mass protostars, and the warm gas in outflows, the two components predominantly traced by Herschel observations. I will present our current understanding of where the water vapor is in protostellar systems and the underlying physical and chemical processes leading to this distribution. Through these dedicated observational surveys and complementary modeling efforts, we are now at a stage where we can quantify where the water is during the early stages of star formation.

Safe drinking water and waterborne outbreaks.

PubMed

Moreira, N A; Bondelind, M

2017-02-01

The present work compiles a review on drinking waterborne outbreaks, with the perspective of production and distribution of microbiologically safe water, during 2000-2014. The outbreaks are categorised in raw water contamination, treatment deficiencies and distribution network failure. The main causes for contamination were: for groundwater, intrusion of animal faeces or wastewater due to heavy rain; in surface water, discharge of wastewater into the water source and increased turbidity and colour; at treatment plants, malfunctioning of the disinfection equipment; and for distribution systems, cross-connections, pipe breaks and wastewater intrusion into the network. Pathogens causing the largest number of affected consumers were Cryptosporidium, norovirus, Giardia, Campylobacter, and rotavirus. The largest number of different pathogens was found for the treatment works and the distribution network. The largest number of affected consumers with gastrointestinal illness was for contamination events from a surface water source, while the largest number of individual events occurred for the distribution network.

Development of a consortium for water security and safety: Planning for an early warning system

USGS Publications Warehouse

Clark, R.M.; Adam, N.R.; Atluri, V.; Halem, M.; Vowinkel, E.F.; ,

2004-01-01

The events of September 11, 2001 have raised concerns over the safety and security of the Nation's critical infrastructure including water and waste water systems. In June 2002, the U.S. EPA's Region II Office (New York City), in response to concerns over water security, in collaboration with Rutgers University agreed to establish a Regional Drinking Water Security and Safety Consortium (RDWSSC). Members of the consortium include: Rutgers University's Center for Information Management, Integration and Connectivity (CIMIC), American Water (AW), the Passaic Valley Water Commission (PVWC), the North Jersey District Water Supply Commission (NJDWSC), the N.J. Department of Environmental Protection, the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agencies, Region II Office. In December of 2002 the consortium members signed a memorandum of understanding (MOU) to pursue activities to enhance regional water security. Development of an early warning system for source and distributed water was identified as being of primary importance by the consortium. In this context, an early warning system (EWS) is an integrated system of monitoring stations located at strategic points in a water utilities source waters or in its distribution system, designed to warn against contaminants that might threaten the health and welfare of drinking water consumers. This paper will discuss the consortium's progress in achieving these important objectives.

Biostability analysis for drinking water distribution systems.

PubMed

Srinivasan, Soumya; Harrington, Gregory W

2007-05-01

The ability to limit regrowth in drinking water is referred to as biological stability and depends on the concentration of disinfectant residual and on the concentration of substrate required for the growth of microorganisms. The biostability curve, based on this fundamental concept of biological stability, is a graphical approach to study the two competing effects that determine bacterial regrowth in a distribution system: inactivation due to the presence of a disinfectant, and growth due to the presence of a substrate. Biostability curves are a practical, system specific approach for addressing the problem of bacterial regrowth in distribution systems. This paper presents a standardized algorithm for generating biostability curves and this will enable water utilities to incorporate this approach for their site-specific needs. Using data from pilot scale studies, it was found that this algorithm was applicable to control regrowth of HPC in chlorinated systems where AOC is the growth limiting substrate, and growth of AOB in chloraminated systems, where ammonia is the growth limiting substrate.

Variability of invertebrate abundance in drinking water distribution systems in the Netherlands in relation to biostability and sediment volumes.

PubMed

van Lieverloo, J Hein M; Hoogenboezem, Wim; Veenendaal, Gerrit; van der Kooij, Dick

2012-10-15

A survey of invertebrates in drinking water from treatment works, internal taps and hydrants on mains was carried out by almost all water companies in the Netherlands from September 1993 to August 1995. Aquatic sow bugs (Asellidae, 1-12 mm) and oligochaeta worms (Oligochaeta, 1-100 mm), both known to have caused rare though embarrassing consumer complaints, were found to form 98% of the mean biomass in water flushed from mains. Their numbers in the mains water ranged up to 1500 (mean 37) Asellidae m(-3) and up to 9900 (mean 135) Oligochaeta m(-3). Smaller crustaceans (0.5-2 mm) dominated the numbers in water from mains. e.g. water fleas (Cladocera and Copepoda up to 14,000 m(-3)). Common invertebrates in treated water and in tap water were Rotifera (<1 mm) and nematode worms (Nematoda, <2 mm). No Asellidae, large Oligochaeta (>5 mm) or other large invertebrates were found in 1560 samples of 200 l treated water or tap water. Large variations in invertebrate abundance were found within and between distribution systems. Of the variability of mean biomass in mains per system, 55%, 60% and 63% could statistically be explained by differences in the Biofilm Formation Rate, non-particulate organic matter and the permanganate index of the treated water of the treatment works respectively. A similar correlation was found between mean invertebrate biomass and mean sediment volumes in the distribution systems (R(2) = 52%). Copyright © 2012 Elsevier Ltd. All rights reserved.

Progress on water data integration and distribution: a summary of select U.S. Geological Survey data systems

USGS Publications Warehouse

Blodgett, David L.; Lucido, Jessica M.; Kreft, James M.

2016-01-01

Critical water-resources issues ranging from flood response to water scarcity make access to integrated water information, services, tools, and models essential. Since 1995 when the first water data web pages went online, the U.S. Geological Survey has been at the forefront of water data distribution and integration. Today, real-time and historical streamflow observations are available via web pages and a variety of web service interfaces. The Survey has built partnerships with Federal and State agencies to integrate hydrologic data providing continuous observations of surface and groundwater, temporally discrete water quality data, groundwater well logs, aquatic biology data, water availability and use information, and tools to help characterize the landscape for modeling. In this paper, we summarize the status and design patterns implemented for selected data systems. We describe how these systems contribute to a U.S. Federal Open Water Data Initiative and present some gaps and lessons learned that apply to global hydroinformatics data infrastructure.

[Socio-economic aspects of epidemiology of helicobateriosis].

PubMed

Fedichkina, T P; Solenova, L G; Zykova, I E; German, S V; Modestova, A V; Kislitsyn, V A; Rakhmanin, Yu A; Bobrovnitsky, I P

There are considered special social and economic aspects of the epidemiology of Helicobacter pylori. These aspects acquired the particular importance for the last time due to the fact that the provision of the people with pure water has been becoming the focus of the attention of geopolitical and socio-economic interests in a number of countries. The availability ofpure drinking water serves a marker of the socio-economic state of the territory and the population living there. In Russia where different climatic conditions are deposited by considerable regional differences in the conditions of communal services caused both by various level of the socio-economic development of the territory, the supplementation with pure drinking water serves as the social determinant of the ecological conditions of the population’s life. This particularly has impact on the unfeasible technical state of the water distribution systems, microorganism ecology of which can substantially affect public health. The performed by authors a specialized screening ofpresented at the official web site of the joint-stock company «Mosvodokanal» current data concerning the quality of drinking water consumed by 2500 Moscovites, tested for the Helicobacter pylori infection revealed no deviations from the sanitary standards in the water received by the consumers. Along with that, the comparison of the map documents of the distribution of the Helicobacter pylori infection in Moscow with the distribution of citizens’ complaints of the decline of the quality of tap water has revealed a territorial fastening of the high values of the population infection rate of n^ylori and the urban sites with the greatest number of complaints. In the microbial ecology of water-distribution systems there are tightly aligned problems of their epidemiological safety, technical state and economic damage caused by corrosion as a result of microbiotic activity. In contrast to acute bacterial and viral infections which are deemed of the greatest importance when assessing the sanitary condition of water sources and water-distribution systems, the consequences of infection with H. pylori may not be manifestedfor a long time but some years later they may be manifested as serious chronic diseases (from gastritis to adenocarcinoma of the stomach and a wide range of extraintestinal pathologies), which causes great social and economic losses. Thus, the socio-economic aspect of the epidemiology of helicobacteriosis includes at least two components: the technic - the maintenance of the feasible technic and sanitary state of the water distribution systems and the medico-social - expenditures for screening and treatment of infected patients. In total they are an inseparable part of the prevention of socially-important diseases in the public health system.

Series of Case Patients with Nontuberculous Mycobacteria Isolation, Central North Carolina, 2006-2010

EPA Science Inventory

Nontuberculous mycobacteria (NTM) infection/colonization, associated with human morbidity/mortality, is linked to drinking water and drinking water distribution systems. To characterize rates and distribution of NTM isolation among residents living in three North Carolina countie...

Lead in ancient Rome’s city waters

PubMed Central

Delile, Hugo; Blichert-Toft, Janne; Goiran, Jean-Philippe; Keay, Simon; Albarède, Francis

2014-01-01

It is now universally accepted that utilization of lead for domestic purposes and water distribution presents a major health hazard. The ancient Roman world was unaware of these risks. How far the gigantic network of lead pipes used in ancient Rome compromised public health in the city is unknown. Lead isotopes in sediments from the harbor of Imperial Rome register the presence of a strong anthropogenic component during the beginning of the Common Era and the Early Middle Ages. They demonstrate that the lead pipes of the water distribution system increased Pb contents in drinking water of the capital city by up to two orders of magnitude over the natural background. The Pb isotope record shows that the discontinuities in the pollution of the Tiber by lead are intimately entwined with the major issues affecting Late Antique Rome and its water distribution system. PMID:24753588

Detection of Legionella, L. pneumophila and Mycobacterium Avium Complex (MAC) along Potable Water Distribution Pipelines

PubMed Central

Whiley, Harriet; Keegan, Alexandra; Fallowfield, Howard; Bentham, Richard

2014-01-01

Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the other chloramine disinfection. Samples were collected four times over the year to provide seasonal variation and the chlorine or chloramine residual was measured during collection. Legionella spp., L. pneumophila and MAC were detected in both distribution systems throughout the year and were all detected at a maximum concentration of 103 copies/mL in the chlorine disinfected system and 106, 103 and 104 copies/mL respectively in the chloramine disinfected system. The concentrations of these opportunistic pathogens were primarily controlled throughout the distribution network through the maintenance of disinfection residuals. At a dead-end and when the disinfection residual was not maintained significant (p < 0.05) increases in concentration were observed when compared to the concentration measured closest to the processing plant in the same pipeline and sampling period. Total coliforms were not present in any water sample collected. This study demonstrates the ability of Legionella spp., L. pneumophila and MAC to survive the potable water disinfection process and highlights the need for greater measures to control these organisms along the distribution pipeline and at point of use. PMID:25046636

Detection of Legionella, L. pneumophila and Mycobacterium avium complex (MAC) along potable water distribution pipelines.

PubMed

Whiley, Harriet; Keegan, Alexandra; Fallowfield, Howard; Bentham, Richard

2014-07-18

Inhalation of potable water presents a potential route of exposure to opportunistic pathogens and hence warrants significant public health concern. This study used qPCR to detect opportunistic pathogens Legionella spp., L. pneumophila and MAC at multiple points along two potable water distribution pipelines. One used chlorine disinfection and the other chloramine disinfection. Samples were collected four times over the year to provide seasonal variation and the chlorine or chloramine residual was measured during collection. Legionella spp., L. pneumophila and MAC were detected in both distribution systems throughout the year and were all detected at a maximum concentration of 103 copies/mL in the chlorine disinfected system and 106, 103 and 104 copies/mL respectively in the chloramine disinfected system. The concentrations of these opportunistic pathogens were primarily controlled throughout the distribution network through the maintenance of disinfection residuals. At a dead-end and when the disinfection residual was not maintained significant (p < 0.05) increases in concentration were observed when compared to the concentration measured closest to the processing plant in the same pipeline and sampling period. Total coliforms were not present in any water sample collected. This study demonstrates the ability of Legionella spp., L. pneumophila and MAC to survive the potable water disinfection process and highlights the need for greater measures to control these organisms along the distribution pipeline and at point of use.

Plant Minders

NASA Technical Reports Server (NTRS)

1988-01-01

Indoor plants are automatically watered by the Aqua Trends watering system. System draws water from building outlets or from pump/reservoir module and distributes it to the plants via a network of tubes and adjustable nozzles. Key element of system is electronic controller programmed to dispense water according to the needs of various plants in an installation. Adjustable nozzle meters out exactly right amount of water at proper time to the plant it's serving. More than 100 Aqua/Trends systems are in service in the USA, from a simple residential system to a large Mirage III system integrated to water all greenery in a large office or apartment building.

Development of Extended Period Pressure-Dependent Demand Water Distribution Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Judi, David R.; Mcpherson, Timothy N.

2015-03-20

Los Alamos National Laboratory (LANL) has used modeling and simulation of water distribution systems for N-1 contingency analyses to assess criticality of water system assets. Critical components considered in these analyses include pumps, tanks, and supply sources, in addition to critical pipes or aqueducts. A contingency represents the complete removal of the asset from system operation. For each contingency, an extended period simulation (EPS) is run using EPANET. An EPS simulates water system behavior over a time period, typically at least 24 hours. It assesses the ability of a system to respond and recover from asset disruption through distributed storagemore » in tanks throughout the system. Contingencies of concern are identified as those in which some portion of the water system has unmet delivery requirements. A delivery requirement is defined as an aggregation of water demands within a service area, similar to an electric power demand. The metric used to identify areas of unmet delivery requirement in these studies is a pressure threshold of 15 pounds per square inch (psi). This pressure threshold is used because it is below the required pressure for fire protection. Any location in the model with pressure that drops below this threshold at any time during an EPS is considered to have unmet service requirements and is used to determine cascading consequences. The outage area for a contingency is the aggregation of all service areas with a pressure below the threshold at any time during the EPS.« less

DISTRIBUTION SYSTEMS AS RESERVOIRS AND REACTORS FOR INORGANIC CONTAMINANTS

EPA Science Inventory

This paper provides a review of numerous drinking water and geochemical investigations and recent studies of pipe deposits and water treatment materials. This analysis shows that there is growing evidence from analogous natural water systems and some analytical studies that many ...

Interpretation of environmental tracers in groundwater systems with stagnant water zones.

PubMed

Maloszewski, Piotr; Stichler, Willibald; Zuber, Andrzej

2004-03-01

Lumped-parameter models are commonly applied for determining the age of water from time records of transient environmental tracers. The simplest models (e.g. piston flow or exponential) are also applicable for dating based on the decay or accumulation of tracers in groundwater systems. The models are based on the assumption that the transit time distribution function (exit age distribution function) of the tracer particles in the investigated system adequately represents the distribution of flow lines and is described by a simple function. A chosen or fitted function (called the response function) describes the transit time distribution of a tracer which would be observed at the output (discharge area, spring, stream, or pumping wells) in the case of an instantaneous injection at the entrance (recharge area). Due to large space and time scales, response functions are not measurable in groundwater systems, therefore, functions known from other fields of science, mainly from chemical engineering, are usually used. The type of response function and the values of its parameters define the lumped-parameter model of a system. The main parameter is the mean transit time of tracer through the system, which under favourable conditions may represent the mean age of mobile water. The parameters of the model are found by fitting calculated concentrations to the experimental records of concentrations measured at the outlet. The mean transit time of tracer (often called the tracer age), whether equal to the mean age of water or not, serves in adequate combinations with other data for determining other useful parameters, e.g. the recharge rate or the content of water in the system. The transit time distribution and its mean value serve for confirmation or determination of the conceptual model of the system and/or estimation of its potential vulnerability to anthropogenic pollution. In the interpretation of environmental tracer data with the aid of the lumped-parameter models, the influence of diffusion exchange between mobile water and stagnant or quasi-stagnant water is seldom considered, though it leads to large differences between tracer and water ages. Therefore, the article is focused on the transit time distribution functions of the most common lumped-parameter models, particularly those applicable for the interpretation of environmental tracer data in double-porosity aquifers, or aquifers in which aquitard diffusion may play an important role. A case study is recalled for a confined aquifer in which the diffusion exchange with aquitard most probably strongly influenced the transport of environmental tracers. Another case study presented is related to the interpretation of environmental tracer data obtained from lysimeters installed in the unsaturated zone with a fraction of stagnant water.

Comparison of Particle-Associated Bacteria from a Drinking Water Treatment Plant and Distribution Reservoirs with Different Water Sources.

PubMed

Liu, G; Ling, F Q; van der Mark, E J; Zhang, X D; Knezev, A; Verberk, J Q J C; van der Meer, W G J; Medema, G J; Liu, W T; van Dijk, J C

2016-02-02

This study assessed the characteristics of and changes in the suspended particles and the associated bacteria in an unchlorinated drinking water distribution system and its reservoirs with different water sources. The results show that particle-associated bacteria (PAB) were present at a level of 0.8-4.5 × 10(3) cells ml(-1) with a biological activity of 0.01-0.04 ng l(-1) ATP. Different PAB communities in the waters produced from different sources were revealed by a 16S rRNA-based pyrosequencing analysis. The quantified biomass underestimation due to the multiple cells attached per particle was ≥ 85%. The distribution of the biologically stable water increased the number of cells per particle (from 48 to 90) but had minor effects on the PAB community. Significant changes were observed at the mixing reservoir. Our results show the characteristics of and changes in suspended PAB during distribution, and highlight the significance of suspended PAB in the distribution system, because suspended PAB can lead to a considerable underestimation of biomass, and because they exist as biofilm, which has a greater mobility than pipe-wall biofilm and therefore presents a greater risk, given the higher probability that it will reach the customers' taps and be ingested.

Risk Assessment in Relation to the Effect of Climate Change on Water Shortage in the Taichung Area

NASA Astrophysics Data System (ADS)

Hsiao, J.; Chang, L.; Ho, C.; Niu, M.

2010-12-01

Rapid economic development has stimulated a worldwide greenhouse effect and induced global climate change. Global climate change has increased the range of variation in the quantity of regional river flows between wet and dry seasons, which effects the management of regional water resources. Consequently, the influence of climate change has become an important issue in the management of regional water resources. In this study, the Monte Carlo simulation method was applied to risk analysis of shortage of water supply in the Taichung area. This study proposed a simulation model that integrated three models: weather generator model, surface runoff model, and water distribution model. The proposed model was used to evaluate the efficiency of the current water supply system and the potential effectiveness of two additional plans for water supply: the “artificial lakes” plan and the “cross-basin water transport” plan. A first-order Markov Chain method and two probability distribution models, exponential distribution and normal distribution, were used in the weather generator model. In the surface runoff model, researchers selected the Generalized Watershed Loading Function model (GWLF) to simulate the relationship between quantity of rainfall and basin outflow. A system dynamics model (SD) was applied to the water distribution model. Results of the simulation indicated that climate change could increase the annual quantity of river flow in the Dachia River and Daan River basins. However, climate change could also increase the difference in the quantity of river flow between wet and dry seasons. Simulation results showed that in current system case or in the additional plan cases, shortage status of water for both public and agricultural uses with conditions of climate change will be mostly worse than that without conditions of climate change except for the shortage status for the public use in the current system case. With or without considering the effect of climate change, the additional plans, especially the “cross-basin water transport” plan, for water supply could significantly increase the supply of water for public use. The proposed simulation model and results of analysis in this study could provide valuable reference for decision-makers in regards to risk analysis of regional water supply.

Slowly biodegradable organic compounds impact the biostability of non-chlorinated drinking water produced from surface water.

PubMed

Hijnen, W A M; Schurer, R; Bahlman, J A; Ketelaars, H A M; Italiaander, R; van der Wal, A; van der Wielen, P W J J

2018-02-01

It is possible to distribute drinking water without a disinfectant residual when the treated water is biologically stable. The objective of this study was to determine the impact of easily and slowly biodegradable compounds on the biostability of the drinking water at three full-scale production plants which use the same surface water, and on the regrowth conditions in the related distribution systems. Easily biodegradable compounds in the drinking water were determined with AOC-P17/Nox during 2012-2015. Slowly biodegradable organic compounds measured as particulate and/or high-molecular organic carbon (PHMOC), were monitored at the inlet and after the different treatment stages of the three treatments during the same period. The results show that PHMOC (300-470 μg C L -1 ) was approximately 10% of the TOC in the surface water and was removed to 50-100 μg C L -1 . The PHMOC in the water consisted of 40-60% of carbohydrates and 10% of proteins. A significant and strong positive correlation was observed for PHMOC concentrations and two recently introduced bioassay methods for slowly biodegradable compounds (AOC-A3 and biomass production potential, BPC 14 ). Moreover, these three parameters in the biological active carbon effluent (BACF) of the three plants showed a positive correlation with regrowth in the drinking water distribution system, which was assessed with Aeromonas, heterotrophic plate counts, coliforms and large invertebrates. In contrast, the AOC-P17/Nox concentrations did not correlate with these regrowth parameters. We therefore conclude that slowly biodegradable compounds in the treated water from these treatment plants seem to have a greater impact on regrowth in the distribution system than easily biodegradable compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Anomalous behavior of poly(ethylene glycol) p-tert-octylphenyl ether (Triton X-100) in the water-cyclohexane system

NASA Astrophysics Data System (ADS)

Chernysheva, M. G.; Tyasto, Z. A.; Badun, G. A.

2009-02-01

The distribution of Triton X-100 nonionic surfactant in the water-cyclohexane system was investigated by the scintillating phase method. It was shown that an increase in the distribution coefficient as the volume ratio between the aqueous and organic phases grew was explained by the presence in Triton X-100 of homologues with different numbers of ethoxyethyl groups and with the distribution coefficients between the phases different by many times. For the real composition of Triton X-100, distribution coefficients of components of the surfactant were estimated, and the behavior of the surfactant in the system under consideration was simulated; the results were in close agreement with the experimental data.

Nitrate, Nitrite, and Ammonium Variability in Drinking Water Distribution Systems.

PubMed

Schullehner, Jörg; Stayner, Leslie; Hansen, Birgitte

2017-03-09

Accurate assessments of exposure to nitrate in drinking water is a crucial part of epidemiological studies investigating long-term adverse human health effects. However, since drinking water nitrate measurements are usually collected for regulatory purposes, assumptions on (1) the intra-distribution system variability and (2) short-term (seasonal) concentration variability have to be made. We assess concentration variability in the distribution system of nitrate, nitrite, and ammonium, and seasonal variability in all Danish public waterworks from 2007 to 2016. Nitrate concentrations at the exit of the waterworks are highly correlated with nitrate concentrations within the distribution net or at the consumers' taps, while nitrite and ammonium concentrations are generally lower within the net compared with the exit of the waterworks due to nitrification. However, nitrification of nitrite and ammonium in the distribution systems only results in a relatively small increase in nitrate concentrations. No seasonal variation for nitrate, nitrite, or ammonium was observed. We conclude that nitrate measurements taken at the exit of the waterworks are suitable to calculate exposures for all consumers connected to that waterworks and that sampling frequencies in the national monitoring programme are sufficient to describe temporal variations in longitudinal studies.

Nitrate, Nitrite, and Ammonium Variability in Drinking Water Distribution Systems

PubMed Central

Schullehner, Jörg; Stayner, Leslie; Hansen, Birgitte

2017-01-01

Accurate assessments of exposure to nitrate in drinking water is a crucial part of epidemiological studies investigating long-term adverse human health effects. However, since drinking water nitrate measurements are usually collected for regulatory purposes, assumptions on (1) the intra-distribution system variability and (2) short-term (seasonal) concentration variability have to be made. We assess concentration variability in the distribution system of nitrate, nitrite, and ammonium, and seasonal variability in all Danish public waterworks from 2007 to 2016. Nitrate concentrations at the exit of the waterworks are highly correlated with nitrate concentrations within the distribution net or at the consumers’ taps, while nitrite and ammonium concentrations are generally lower within the net compared with the exit of the waterworks due to nitrification. However, nitrification of nitrite and ammonium in the distribution systems only results in a relatively small increase in nitrate concentrations. No seasonal variation for nitrate, nitrite, or ammonium was observed. We conclude that nitrate measurements taken at the exit of the waterworks are suitable to calculate exposures for all consumers connected to that waterworks and that sampling frequencies in the national monitoring programme are sufficient to describe temporal variations in longitudinal studies. PMID:28282914

Temporal changes in the vertical distribution of flow and chloride in deep wells.

PubMed

Izbicki, John A; Christensen, Allen H; Newhouse, Mark W; Smith, Gregory A; Hanson, Randall T

2005-01-01

The combination of flowmeter and depth-dependent water-quality data was used to evaluate the quantity and source of high-chloride water yielded from different depths to eight production wells in the Pleasant Valley area of southern California. The wells were screened from 117 to 437 m below land surface, and in most cases, flow from the aquifer into the wells was not uniformly distributed throughout the well screen. Wells having as little as 6 m of screen in the overlying upper aquifer system yielded as much as 50% of their water from the upper system during drought periods, while the deeper parts of the well screens yielded 15% or less of the total yield of the wells. Mixing of water within wells during pumping degraded higher-quality water with poorer-quality water from deeper depths, and in some cases with poorer-quality water from the overlying upper aquifer system. Changes in the mixture of water within a well, resulting from changes in the distribution of flow into the well, changed the quality of water from the surface discharge of wells over time. The combination of flowmeter and depth-dependent water quality data yielded information about sources of high-chloride water to wells that was not available on the basis of samples collected from nearby observation wells. Changing well design to eliminate small quantities of poor-quality water from deeper parts of the well may improve the quality of water from some wells without greatly reducing well yield.

An ignored and potential source of taste and odor (T&O) issues-biofilms in drinking water distribution system (DWDS).

PubMed

Zhou, Xinyan; Zhang, Kejia; Zhang, Tuqiao; Li, Cong; Mao, Xinwei

2017-05-01

It is important for water utilities to provide esthetically acceptable drinking water to the public, because our consumers always initially judge the quality of the tap water by its color, taste, and odor (T&O). Microorganisms in drinking water contribute largely to T&O production and drinking water distribution systems (DWDS) are known to harbor biofilms and microorganisms in bulk water, even in the presence of a disinfectant. These microbes include T&O-causing bacteria, fungi, and algae, which may lead to unwanted effects on the organoleptic quality of distributed water. Importantly, the understanding of types of these microbes and their T&O compound-producing mechanisms is needed to prevent T&O formation during drinking water distribution. Additionally, new disinfection strategies and operation methods of DWDS are also needed for better control of T&O problems in drinking water. This review covers: (1) the microbial species which can produce T&O compounds in DWDS; (2) typical T&O compounds in DWDS and their formation mechanisms by microorganisms; (3) several common factors in DWDS which can influence the growth and T&O generation of microbes; and (4) several strategies to control biofilm and T&O compound formation in DWDS. At the end of this review, recommendations were given based on the conclusion of this review.

Asellus aquaticus as a Potential Carrier of Escherichia coli and Other Coliform Bacteria into Drinking Water Distribution Systems

PubMed Central

Christensen, Sarah C. B.; Arvin, Erik; Nissen, Erling; Albrechtsen, Hans-Jørgen

2013-01-01

Individuals of the water louse, Asellus aquaticus, enter drinking water distribution systems in temperate parts of the world, where they establish breeding populations. We analysed populations of surface water A. aquaticus from two ponds for associated faecal indicator bacteria and assessed the risk of A. aquaticus transporting bacteria into distribution systems. Concentrations of up to two E. coli and five total coliforms·mL−1 were measured in the water and 200 E. coli and >240 total coliforms·mL−1 in the sediments of the investigated ponds. Concentrations of A. aquaticus associated bacteria never exceeded three E. coli and six total coliforms·A. aquaticus−1. During exposure to high concentrations of coliforms, concentrations reached 350 coliforms·A. aquaticus−1. A. aquaticus associated E. coli were only detected as long as E. coli were present in the water and sediment. The calculated probability of exceeding drinking water guideline values in non-disinfected systems by intrusion of A. aquaticus was low. Only in scenarios with narrow pipes and low flows, did total coliforms exceed guideline values, implying that the probability of detection by routine monitoring is also low. The study expands the knowledge base for evaluating incidents with presence of coliform indicators in drinking water by showing that intruding A. aquaticus were not important carriers of E. coli or other coliform bacteria even when emerging from faecally contaminated waters. PMID:23455399

Asellus aquaticus as a potential carrier of Escherichia coli and other coliform bacteria into drinking water distribution systems.

PubMed

Christensen, Sarah C B; Arvin, Erik; Nissen, Erling; Albrechtsen, Hans-Jørgen

2013-03-01

Individuals of the water louse, Asellus aquaticus, enter drinking water distribution systems in temperate parts of the world, where they establish breeding populations. We analysed populations of surface water A. aquaticus from two ponds for associated faecal indicator bacteria and assessed the risk of A. aquaticus transporting bacteria into distribution systems. Concentrations of up to two E. coli and five total coliforms·mL-1 were measured in the water and 200 E. coli and >240 total coliforms·mL-1 in the sediments of the investigated ponds. Concentrations of A. aquaticus associated bacteria never exceeded three E. coli and six total coliforms·A. aquaticus-1. During exposure to high concentrations of coliforms, concentrations reached 350 coliforms·A. aquaticus-1. A. aquaticus associated E. coli were only detected as long as E. coli were present in the water and sediment. The calculated probability of exceeding drinking water guideline values in non-disinfected systems by intrusion of A. aquaticus was low. Only in scenarios with narrow pipes and low flows, did total coliforms exceed guideline values, implying that the probability of detection by routine monitoring is also low. The study expands the knowledge base for evaluating incidents with presence of coliform indicators in drinking water by showing that intruding A. aquaticus were not important carriers of E. coli or other coliform bacteria even when emerging from faecally contaminated waters.

Bacterial community of iron tubercles from a drinking water distribution system and its occurrence in stagnant tap water.

PubMed

Chen, Lu; Jia, Rui-Bao; Li, Li

2013-07-01

Bacteria in drinking water distribution systems can cause deterioration of the water quality, and the microbial quality of tap water is closely related to consumer health. In the present study, the potential effects of bacteria attached to cast iron pipes on tap water in a distribution system were investigated. Comparison of the bacterial community composition of pipe tubercles with that of stagnant tap water samples based on a denaturing gradient gel electrophoresis analysis of the 16S rRNA gene revealed that the communities were related. Specifically, the main bacterial members were identical to each other. The bacterial community was found to be dominated by Firmicutes, Actinobacteria, and Proteobacteria, which included Rhizobium, Pseudomonas, Lactococcus, Brevundimonas, Rheinheimera, Arthrobacter, Bacillus, and Herbaspirillum. Heterotrophic bacteria proliferation was observed during the period of stagnation, followed by a decrease of assimilable organic carbon and a slight increase of microbially available phosphorus. These findings indicated that the regrowth of bacteria might be boosted by the release of nutrients such as phosphorus from the pipe walls, as well as the decline of residual chlorine during stagnation. Inorganic contaminants at low levels, including Al, Mn, Zn, Pb, Cr, Cu, and Ni, were detected in tubercles and were concentrated in particulates from tap water following the release of iron during stagnation.

An integrated logit model for contamination event detection in water distribution systems.

PubMed

Housh, Mashor; Ostfeld, Avi

2015-05-15

The problem of contamination event detection in water distribution systems has become one of the most challenging research topics in water distribution systems analysis. Current attempts for event detection utilize a variety of approaches including statistical, heuristics, machine learning, and optimization methods. Several existing event detection systems share a common feature in which alarms are obtained separately for each of the water quality indicators. Unifying those single alarms from different indicators is usually performed by means of simple heuristics. A salient feature of the current developed approach is using a statistically oriented model for discrete choice prediction which is estimated using the maximum likelihood method for integrating the single alarms. The discrete choice model is jointly calibrated with other components of the event detection system framework in a training data set using genetic algorithms. The fusing process of each indicator probabilities, which is left out of focus in many existing event detection system models, is confirmed to be a crucial part of the system which could be modelled by exploiting a discrete choice model for improving its performance. The developed methodology is tested on real water quality data, showing improved performances in decreasing the number of false positive alarms and in its ability to detect events with higher probabilities, compared to previous studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nuclear decontamination technology evaluation to address contamination of a municipal water system

DOE Office of Scientific and Technical Information (OSTI.GOV)

McFee, J.; Langsted, J.; Young, M.

The US Environmental Protection Agency (EPA) and US Department of Homeland Security (DHS) are considering the impact and recovery from contamination of municipal water systems, including intentional contamination of those systems. Industrial chemicals, biological agents, drugs, pesticides, chemical warfare agents, and radionuclides all could be introduced into a municipal water system to create detrimental health effects and disrupt a community. Although unintentional, the 1993 cryptosporidium contamination of the Milwaukee WS water system resulted in 100 fatalities and disrupted the city for weeks. Shaw Environmental and Infrastructure Inc, (Shaw), as a subcontractor on a DHS contract with Michael Baker Jr., Inc.,more » was responsible for evaluation of the impact and recovery from radionuclide contamination in a municipal water system distribution system. Shaw was tasked to develop a matrix of nuclear industry decontamination technologies and evaluate applicability to municipal water systems. Shaw expanded the evaluation to include decontamination methods commonly used in the drinking water supply. The matrix compared all technologies for implementability, effectiveness, and cost. To address the very broad range of contaminants and contamination scenarios, Shaw bounded the problem by identification of specific contaminant release scenario(s) for specific water system architecture(s). A decontamination technology matrix was developed containing fifty-nine decontamination technologies potentially applicable to the water distribution system piping, pumps, tanks, associated equipment, and/or contaminated water. Qualitatively, the majority of the nuclear industry decontamination technologies were eliminated from consideration due to implementability concerns. However, inclusion of the municipal water system technologies supported recommendations that combined the most effective approaches in both industries. (authors)« less

COMPARISON OF MYCOBACTERIUM AVIUM ISOLATES FROM A DRINKING WATER DISTRIBUTION SYSTEM AND FROM THE POPULATION SERVED BY THE SYSTEM

EPA Science Inventory

Background: Current evidence suggests that drinking water, soil, and produce are potential sources of Mycobacterium avium infections, a pathogen not known to be transmitted person-to-person.

Methods: We sampled water during 2000-2002 from a large municipal drinking water ...

GEOPHYSICAL CHARACTERIZATION, REDOX ZONATION, AND CONTAMINANT DISTRIBUTION AT A GROUNDWATER/SURFACE WATER INTERFACE

EPA Science Inventory

Three transects along a groundwater/surface water interface were characterized for spatial distributions of chlorinated aliphatic hydrocarbons and geochemical conditions to evaluate the natural bioremediation potential of this environmental system. Partly on the basis of ground p...

THE EPANET PROGRAMMER'S TOOLKIT FOR ANALYSIS OF WATER DISTRIBUTION SYSTEMS

EPA Science Inventory

The EPANET Programmer's Toolkit is a collection of functions that helps simplify computer programming of water distribution network analyses. the functions can be used to read in a pipe network description file, modify selected component properties, run multiple hydraulic and wa...

Threshold groundwater ages and young water fractions estimated from 3H, 3He, and 14C

NASA Astrophysics Data System (ADS)

Kirchner, James; Jasechko, Scott

2016-04-01

It is widely recognized that a water sample taken from a running stream is not described by a single age, but rather by a distribution of ages. It is less widely recognized that the same principle holds true for groundwaters, as indicated by the commonly observed discordances between model ages obtained from different tracers (e.g., 3H vs 14C) in the same sample. Water age distributions are often characterized by their mean residence times (MRT's). However, MRT estimates are highly uncertain because they depend on the shape of the assumed residence time distribution (in particular on the thickness of the long-time tail), which is difficult or impossible to constrain with data. Furthermore, because MRT's are typically nonlinear functions of age tracer concentrations, they are subject to aggregation bias. That is, MRT estimates derived from a mixture of waters with different ages (and thus different tracer concentrations) will systematically underestimate the mixture's true mean age. Here, building on recent work with stable isotope tracers in surface waters [1-3], we present a new framework for using 3H, 3He and 14C to characterize groundwater age distributions. Rather than describing groundwater age distributions by their MRT, we characterize them by the fraction of the distribution that is younger or older than a threshold age. The threshold age that separates "young" from "old" water depends on the characteristics of the specific tracer, including its history of atmospheric inputs. Our approach depends only on whether a given slice of the age distribution is younger or older than the threshold age, but not on how much younger or older it is. Thus our approach is insensitive to the tails of the age distribution, and is therefore relatively unaffected by uncertainty in the distribution's shape. Here we show that concentrations of 3H, 3He, and 14C are almost linearly related to the fractions of water that are younger or older than specified threshold ages. These "young" and "old" water fractions are therefore immune to the aggregation bias that afflicts MRT estimates. They are also relatively insensitive to the shape of the assumed residence time distribution. We apply this approach to 3H and 14C measurements from ˜5000 wells in ˜200 aquifers around the world. Our results show that even very old groundwaters, with 14C ages of thousands of years, often contain significant amounts of much younger water, with a substantial fraction of their age distributions younger than ˜100 years old. Thus despite being very old on average, these groundwaters may also be vulnerable to relatively recent contamination. [1] Kirchner J.W., Aggregation in environmental systems: Catchment mean transit times and young water fractions under hydrologic nonstationarity, Hydrology and Earth System Sciences, in press. [2] Kirchner J.W., Aggregation in environmental systems: Seasonal tracer cycles quantify young water fractions, but not mean transit times, in spatially heterogeneous catchments, Hydrology and Earth System Sciences, in press. [3] Jasechko S., Kirchner J.W., Welker J.M., and McDonnell J.J., Substantial young streamflow in global rivers, Nature Geoscience, in press.

Ancestral irrigation method by kanis in Bolivia

NASA Astrophysics Data System (ADS)

Roldán-Cañas, José; Chipana, René; Fátima Moreno-Pérez, María

2015-04-01

Irrigation in the Andean region is an ancient practice. For centuries, farmers were able to use the waters of rivers, lakes and springs to complement or supplement the scarce rainfall regime. The inter-Andean valleys of the Department of La Paz are the best areas for the study of traditional irrigation systems. This work has been carried out in the community of Jatichulaya located in te town of Charazani, 300 km from the city of La Paz, which lies 3250 meters above sea level. The annual rainfall ranges around 450 mm distributed mainly between the months of December to March. Therefore, water is needed to achieve adequate crop yields. The traditional irrigation system is done by the method of Kanis, consisting of a surface irrigation already developed by traditional Andean cultures of the country, in harmony with the ecological and productive characteristics of the area. Water enters the irrigation plot through a main channel (mama kani) from which the secondary channels (juchuy kanis) are derived. The fundamental characteristic of this irrigation is that these channels are open at the same time the water enters into the plot. The system works properly, adapting to the topography of the area. The irrigation method practiced in this community does not cause water erosion of soils because water management within the plot is based on the ancient knowledge of farmers following the contour lines. This practice allows good irrigation development and soil protection without causing any problems. However, it was evident a high use of labor in irrigation practice. Irrigation scheduling is done according to requests made by the irrigators in a given period. Delivering of water to the farmers is made by the so-called Water Agent (Agente de Aguas) or person in charge of the distribution of water. The Water Agent is elected annually and its functions include the maintenance and care of all system waterworks. The period between August and January is the highest water demand and, therefore, the water is distributed by turns among irrigators. Turns usually depend on water availability. Water Agent distributes water equitably without giving preference to anyone.

THE ACCUMULATION AND RELEASE OF CONTAMINANTS FROM DISTRIBUTION SYSTEM SOLIDS

EPA Science Inventory

The recently promulgated Arsenic Rule will require that many new drinking water systems treat their water to remove arsenic. Iron based treatment technologies including iron removal and iron coagulation are effective at reducing arsenic in water because iron surfaces have a stron...

DECISION-SUPPORT TOOLS FOR PREDICTING THE PERFORMANCE OF WATER DISTRIBUTION AND WASTEWATER COLLECTION SYSTEMS

EPA Science Inventory

Water and wastewater infrastructure systems represent a major capital investment; utilities must ensure they are getting the highest yield possible on their investment, both in terms of dollars and water quality. Accurate information related to equipment, pipe characteristics, l...

DECISION-SUPPORT TOOLS FOR PREDICTING THE PERFORMANCE OF WATER DISTRIBUTION AND WASTEWATER COLLECTION SYSTEMS

EPA Science Inventory

Water and wastewater infrastructure systems represent a major capital investment; utilities must ensure they are getting the highest yield possible on their investment, both in terms of dollars and water quality. Accurate information related to equipment, pipe characteristics, lo...

Residence time distributions of artificially infiltrated groundwater used for drinking water production

NASA Astrophysics Data System (ADS)

Popp, A. L.; Marçais, J.; Moeck, C.; Brennwald, M. S.; Kipfer, R.

2017-12-01

Public drinking water supply in urban areas is often challenging due to exposure to potential contamination and high water demands. At our study site, a drinking water supply field in Switzerland, managed aquifer recharge (MAR) was implemented to overcome an increasing water demand and decreasing water quality. Water from the river Rhine is put on a system of channels and ponds to artificially infiltrate and hence, increase the natural groundwater availability. The groundwater system consists of two overlying aquifers, with hydraulic connections related to fractures and faults. The deeper aquifer contains contaminants, which possibly originate from nearby landfills and industrial areas. The operating water works aims to pump recently infiltrated water only. However, we suspect that the pumped water contains a fraction of old water due to the fractured zones which serve as hydraulic connection between the two aquifers. With this study, we aim to better understand the mixing patterns between recently infiltrated water and old groundwater to evaluate the risk for contamination of the system. To reach our objective, we used a set of gas tracers (222Rn, 3H/3He, 4He) from fifteen wells distributed throughout the area to estimate the residence time distribution (RTD) of each well. We calibrated the RTD with a Binary Mixing Model, where the fraction of young groundwater is assumed to follow a Piston Flow Model. The older groundwater fraction is calibrated with a Dispersion Model. Our results reflect the heterogeneity of the system with some abstraction wells containing young water only and others showing an admixture of old water which can only be explained by a connection to the deeper aquifer. We also show that our results on calibrated RTDs are in accordance with other geochemical data such as electrical conductivity, major ions and pH. Our results will contribute to a sound conceptual flow and transport understanding and will help to optimize the water supply system.

JPL Physical Oceanography Distributed Active Archive Center (PO.DAAC) data availability, version 1-94

NASA Technical Reports Server (NTRS)

1994-01-01

The Physical Oceanography Distributed Active Archive Center (PO.DAAC) archive at the Jet Propulsion Laboratory (JPL) includes satellite data sets for the ocean sciences and global-change research to facilitate multidisciplinary use of satellite ocean data. Parameters include sea-surface height, surface-wind vector, sea-surface temperature, atmospheric liquid water, and integrated water vapor. The JPL PO.DAAC is an element of the Earth Observing System Data and Information System (EOSDIS) and is the United States distribution site for Ocean Topography Experiment (TOPEX)/POSEIDON data and metadata.

Fungi from a Groundwater-Fed Drinking Water Supply System in Brazil

PubMed Central

Oliveira, Helena M.B.; Santos, Cledir; Paterson, R. Russell M.; Gusmão, Norma B.; Lima, Nelson

2016-01-01

Filamentous fungi in drinking water distribution systems are known to (a) block water pipes; (b) cause organoleptic biodeterioration; (c) act as pathogens or allergens and (d) cause mycotoxin contamination. Yeasts might also cause problems. This study describes the occurrence of several fungal species in a water distribution system supplied by groundwater in Recife—Pernambuco, Brazil. Water samples were collected from four sampling sites from which fungi were recovered by membrane filtration. The numbers in all sampling sites ranged from 5 to 207 colony forming units (CFU)/100 mL with a mean value of 53 CFU/100 mL. In total, 859 isolates were identified morphologically, with Aspergillus and Penicillium the most representative genera (37% and 25% respectively), followed by Trichoderma and Fusarium (9% each), Curvularia (5%) and finally the species Pestalotiopsis karstenii (2%). Ramichloridium and Leptodontium were isolated and are black yeasts, a group that include emergent pathogens. The drinking water system in Recife may play a role in fungal dissemination, including opportunistic pathogens. PMID:27005653

Fungi from a Groundwater-Fed Drinking Water Supply System in Brazil.

PubMed

Oliveira, Helena M B; Santos, Cledir; Paterson, R Russell M; Gusmão, Norma B; Lima, Nelson

2016-03-09

Filamentous fungi in drinking water distribution systems are known to (a) block water pipes; (b) cause organoleptic biodeterioration; (c) act as pathogens or allergens and (d) cause mycotoxin contamination. Yeasts might also cause problems. This study describes the occurrence of several fungal species in a water distribution system supplied by groundwater in Recife-Pernambuco, Brazil. Water samples were collected from four sampling sites from which fungi were recovered by membrane filtration. The numbers in all sampling sites ranged from 5 to 207 colony forming units (CFU)/100 mL with a mean value of 53 CFU/100 mL. In total, 859 isolates were identified morphologically, with Aspergillus and Penicillium the most representative genera (37% and 25% respectively), followed by Trichoderma and Fusarium (9% each), Curvularia (5%) and finally the species Pestalotiopsis karstenii (2%). Ramichloridium and Leptodontium were isolated and are black yeasts, a group that include emergent pathogens. The drinking water system in Recife may play a role in fungal dissemination, including opportunistic pathogens.

Harvested rainwater quality before and after treatment in six ...

EPA Pesticide Factsheets

Rainwater harvesting (RWH) is an alternative method of providing water for indoor domestic use, but the water quality after treatment and distribution at individual residences is not well documented. In this study, water quality parameters were measured at the cistern and indoor cold-water taps of six residential RWH systems that use various treatment processes. Potential human pathogens (Mycobacterium avium, Mycobacterium intracellulare, Aspergillus flavus, Aspergillus fumigatus, and Aspergillus niger) were found frequently in cisterns and in treated rainwater delivered at the tap; Legionella pneumophila was not detected as frequently, but it persisted in a system after its first detection. The observed decreases in bacterial concentrations from the cistern to the tap after filtration/ ultraviolet (UV) treatment and distribution were less than expected; this suggests deficiencies in the effectiveness of the filtration/UV processes employed and/or degradation in water quality in the distribution system due to the absence of a disinfectant residual. Determination of the disinfection efficiency occuring in home treatment processes. Molecular analysis of rainwater before and after treatment. First study to include the monitoring of opportunistic fungal pathogens.

Assessment of drinking water quality at the tap using fluorescence spectroscopy.

PubMed

Heibati, Masoumeh; Stedmon, Colin A; Stenroth, Karolina; Rauch, Sebastien; Toljander, Jonas; Säve-Söderbergh, Melle; Murphy, Kathleen R

2017-11-15

Treated drinking water may become contaminated while travelling in the distribution system on the way to consumers. Elevated dissolved organic matter (DOM) at the tap relative to the water leaving the treatment plant is a potential indicator of contamination, and can be measured sensitively, inexpensively and potentially on-line via fluorescence and absorbance spectroscopy. Detecting elevated DOM requires potential contamination events to be distinguished from natural fluctuations in the system, but how much natural variation to expect in a stable distribution system is unknown. In this study, relationships between DOM optical properties, microbial indicator organisms and trace elements were investigated for households connected to a biologically-stable drinking water distribution system. Across the network, humic-like fluorescence intensities showed limited variation (RSD = 3.5-4.4%), with half of measured variation explained by interactions with copper. After accounting for quenching by copper, fluorescence provided a very stable background signal (RSD < 2.2%) against which a ∼2% infiltration of soil water would be detectable. Smaller infiltrations would be detectable in the case of contamination by sewage with a strong tryptophan-like fluorescence signal. These findings indicate that DOM fluorescence is a sensitive indicator of water quality changes in drinking water networks, as long as potential interferents are taken into account. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Microbial distribution in the Environmental Control and Life Support System water recovery test conducted at NASA, MSFC

NASA Technical Reports Server (NTRS)

Gauthier, J. J.; Roman, M. C.; Kilgore, B. A.; Huff, T. L.; Obenhuber, D. C.; Terrell, D. W.; Wilson, M. E.; Jackson, N. E.

1991-01-01

NASA/MSFC is developing a physical/chemical treatment system to reclaim wastewater for reuse on Space Station Freedom (SSF). Integrated testing of hygiene and potable water subsystems assessed the capability to reclaim water to SSF specifications. The test was conducted from May through July 1990 with a total of 47 days of system test operation. Water samples were analyzed using standard cultural methods employing membrane filtration and spread plate techniques and epifluorescence microscopy. Fatty acid methyl ester and biochemical profiles were used for microbial identification. Analysis of waste and product water produced by the subsystems demonstrated the effective reduction of viable microbial populations greater than 8.0E + 06 colony forming units (CFU) per 100 mL to an average of 5 CFU/100 mL prior to distribution into storage tanks.

Retrofitting a water-pumping station with adjustable speed drives: Feasibility analysis: Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1988-08-01

The objective of this report is to develop a generalized methodology for examining water distribution systems for adjustable speed drive (ASD) applications and to provide an example (the City of Chicago 68th Street Water Pumping Station) using the methodology. The City of Chicago water system was chosen as the candidate for analysis because it has a large service area distribution network with no storage provisions after the distribution pumps. Many industrial motors operate at only one speed or a few speeds. By speeding up or slowing down, ASDs achieve gentle startups and gradual shutdowns thereby providing plant equipment a longermore » life with fewer breakdowns while minimizing the energy requirements. The test program substantiated that ASDs enhance product quality and increase productivity in many industrial operations, including extended equipment life. 35 figs.« less

Asset deterioration and discolouration in water distribution systems.

PubMed

Husband, P S; Boxall, J B

2011-01-01

Water Distribution Systems function to supply treated water safe for human consumption and complying with increasingly stringent quality regulations. Considered primarily an aesthetic issue, discolouration is the largest cause of customer dissatisfaction associated with distribution system water quality. Pro-active measures to prevent discolouration are sought yet network processes remain insufficiently understood to fully justify and optimise capital or operational strategies to manage discolouration risk. Results are presented from a comprehensive fieldwork programme in UK water distribution networks that have determined asset deterioration with respect to discolouration. This is achieved by quantification of material accumulating as cohesive layers on pipe surfaces that when mobilised are acknowledged as the primary cause of discolouration. It is shown that these material layers develop ubiquitously with defined layer strength characteristics and at a consistent and repeatable rate dependant on water quality. For UK networks iron concentration in the bulk water is shown as a potential indicator of deterioration rate. With material layer development rates determined, management decisions that balance discolouration risk and expenditure to maintain water quality integrity can be justified. In particular the balance between capital investment such as improving water treatment output or pipe renewal and operational expenditure such as the frequency of network maintenance through flushing may be judged. While the rate of development is shown to be a function of water quality, the magnitude (peak or average turbidity) of discolouration incidents is shown to be dominated by hydraulic conditions. From this it can be proposed that network hydraulic management, such as regular periodic 'stressing', is a potential strategy in reducing discolouration risk. The ultimate application of this is the hydraulic design of self-cleaning networks to maintain discolouration risk below acceptable levels. Copyright © 2010 Elsevier Ltd. All rights reserved.

Distribution of Quercus agrifolia mycorrhizae deep within weathered bedrock: a potential mechanism for transport of stored water

Treesearch

M. Bornyasz; R. Graham; M. Allen

2002-01-01

In southwestern California, Quercus agrifolia distribution closely matches regions of granitic regolith. High annual evapotranspiration demand and inherent shallow soil conditions lead to a dependence on a deep rooting system and an ability to access water from deep within the regolith. Most of the plant available water in weathered granitic rock is...

Intelligent infrastructure for sustainable potable water: a roundtable for emerging transnational research and technology development needs.

PubMed

Adriaens, Peter; Goovaerts, Pierre; Skerlos, Steven; Edwards, Elizabeth; Egli, Thomas

2003-12-01

Recent commercial and residential development have substantially impacted the fluxes and quality of water that recharge the aquifers and discharges to streams, lakes and wetlands and, ultimately, is recycled for potable use. Whereas the contaminant sources may be varied in scope and composition, these issues of urban water sustainability are of public health concern at all levels of economic development worldwide, and require cheap and innovative environmental sensing capabilities and interactive monitoring networks, as well as tailored distributed water treatment technologies. To address this need, a roundtable was organized to explore the potential role of advances in biotechnology and bioengineering to aid in developing causative relationships between spatial and temporal changes in urbanization patterns and groundwater and surface water quality parameters, and to address aspects of socioeconomic constraints in implementing sustainable exploitation of water resources. An interactive framework for quantitative analysis of the coupling between human and natural systems requires integrating information derived from online and offline point measurements with Geographic Information Systems (GIS)-based remote sensing imagery analysis, groundwater-surface water hydrologic fluxes and water quality data to assess the vulnerability of potable water supplies. Spatially referenced data to inform uncertainty-based dynamic models can be used to rank watershed-specific stressors and receptors to guide researchers and policymakers in the development of targeted sensing and monitoring technologies, as well as tailored control measures for risk mitigation of potable water from microbial and chemical environmental contamination. The enabling technologies encompass: (i) distributed sensing approaches for microbial and chemical contamination (e.g. pathogens, endocrine disruptors); (ii) distributed application-specific, and infrastructure-adaptive water treatment systems; (iii) geostatistical integration of monitoring data and GIS layers; and (iv) systems analysis of microbial and chemical proliferation in distribution systems. This operational framework is aimed at technology implementation while maximizing economic and public health benefits. The outcomes of the roundtable will further research agendas in information technology-based monitoring infrastructure development, integration of processes and spatial analysis, as well as in new educational and training platforms for students, practitioners and regulators. The potential for technology diffusion to emerging economies with limited financial resources is substantial.

On the probabilistic structure of water age: Probabilistic Water Age

DOE Office of Scientific and Technical Information (OSTI.GOV)

Porporato, Amilcare; Calabrese, Salvatore

We report the age distribution of water in hydrologic systems has received renewed interest recently, especially in relation to watershed response to rainfall inputs. The purpose of this contribution is first to draw attention to existing theories of age distributions in population dynamics, fluid mechanics and stochastic groundwater, and in particular to the McKendrick-von Foerster equation and its generalizations and solutions. A second and more important goal is to clarify that, when hydrologic fluxes are modeled by means of time-varying stochastic processes, the age distributions must themselves be treated as random functions. Once their probabilistic structure is obtained, it canmore » be used to characterize the variability of age distributions in real systems and thus help quantify the inherent uncertainty in the field determination of water age. Finally, we illustrate these concepts with reference to a stochastic storage model, which has been used as a minimalist model of soil moisture and streamflow dynamics.« less

On the probabilistic structure of water age: Probabilistic Water Age

DOE PAGES

Porporato, Amilcare; Calabrese, Salvatore

2015-04-23

We report the age distribution of water in hydrologic systems has received renewed interest recently, especially in relation to watershed response to rainfall inputs. The purpose of this contribution is first to draw attention to existing theories of age distributions in population dynamics, fluid mechanics and stochastic groundwater, and in particular to the McKendrick-von Foerster equation and its generalizations and solutions. A second and more important goal is to clarify that, when hydrologic fluxes are modeled by means of time-varying stochastic processes, the age distributions must themselves be treated as random functions. Once their probabilistic structure is obtained, it canmore » be used to characterize the variability of age distributions in real systems and thus help quantify the inherent uncertainty in the field determination of water age. Finally, we illustrate these concepts with reference to a stochastic storage model, which has been used as a minimalist model of soil moisture and streamflow dynamics.« less

Molecular survey of the occurrence of Legionella spp., Mycobacterium spp., Pseudomonas aeruginosa, and amoeba hosts in two chloraminated drinking water distribution systems.

PubMed

Wang, Hong; Edwards, Marc; Falkinham, Joseph O; Pruden, Amy

2012-09-01

The spread of opportunistic pathogens via public water systems is of growing concern. The purpose of this study was to identify patterns of occurrence among three opportunistic pathogens (Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa) relative to biotic and abiotic factors in two representative chloraminated drinking water distribution systems using culture-independent methods. Generally, a high occurrence of Legionella (≥69.0%) and mycobacteria (100%), lower occurrence of L. pneumophila (≤20%) and M. avium (≤33.3%), and rare detection of Pseudomonas aeruginosa (≤13.3%) were observed in both systems according to quantitative PCR. Also, Hartmanella vermiformis was more prevalent than Acanthamoeba, both of which are known hosts for opportunistic pathogen amplification, the latter itself containing pathogenic members. Three-minute flushing served to distinguish distribution system water from plumbing in buildings (i.e., premise plumbing water) and resulted in reduced numbers of copies of Legionella, mycobacteria, H. vermiformis, and 16S rRNA genes (P < 0.05) while yielding distinct terminal restriction fragment polymorphism (T-RFLP) profiles of 16S rRNA genes. Within certain subgroups of samples, some positive correlations, including correlations of numbers of mycobacteria and total bacteria (16S rRNA genes), H. vermiformis and total bacteria, mycobacteria and H. vermiformis, and Legionella and H. vermiformis, were noted, emphasizing potential microbial ecological relationships. Overall, the results provide insight into factors that may aid in controlling opportunistic pathogen proliferation in real-world water systems.

Molecular Survey of the Occurrence of Legionella spp., Mycobacterium spp., Pseudomonas aeruginosa, and Amoeba Hosts in Two Chloraminated Drinking Water Distribution Systems

PubMed Central

Wang, Hong; Edwards, Marc; Falkinham, Joseph O.

2012-01-01

The spread of opportunistic pathogens via public water systems is of growing concern. The purpose of this study was to identify patterns of occurrence among three opportunistic pathogens (Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa) relative to biotic and abiotic factors in two representative chloraminated drinking water distribution systems using culture-independent methods. Generally, a high occurrence of Legionella (≥69.0%) and mycobacteria (100%), lower occurrence of L. pneumophila (≤20%) and M. avium (≤33.3%), and rare detection of Pseudomonas aeruginosa (≤13.3%) were observed in both systems according to quantitative PCR. Also, Hartmanella vermiformis was more prevalent than Acanthamoeba, both of which are known hosts for opportunistic pathogen amplification, the latter itself containing pathogenic members. Three-minute flushing served to distinguish distribution system water from plumbing in buildings (i.e., premise plumbing water) and resulted in reduced numbers of copies of Legionella, mycobacteria, H. vermiformis, and 16S rRNA genes (P < 0.05) while yielding distinct terminal restriction fragment polymorphism (T-RFLP) profiles of 16S rRNA genes. Within certain subgroups of samples, some positive correlations, including correlations of numbers of mycobacteria and total bacteria (16S rRNA genes), H. vermiformis and total bacteria, mycobacteria and H. vermiformis, and Legionella and H. vermiformis, were noted, emphasizing potential microbial ecological relationships. Overall, the results provide insight into factors that may aid in controlling opportunistic pathogen proliferation in real-world water systems. PMID:22752174

Consequences and Reduction of Elevated Ammonia in Illinois Groundwaters: U.S. EPA Research Efforts

EPA Science Inventory

Nitrification in drinking water distribution systems is a concern of many drinking water systems. Although chloramination as a source of nitrification has drawn the most attention, many source waters contain significant levels of ammonia, particularly in Midwestern States such a...

3D Chlorine and Monochloramine Penetration and Nitrifying Biofilm Activity and Viability: Periodic Chlorine Switch Implications

EPA Science Inventory

Biofilm formation in drinking water distribution systems has been associated with water quality degradation and may result in non-compliance with existing regulations. United States water utilities report biofilm survival and regrowth despite disinfectant presence, and systems t...

High-throughput profiling of antibiotic resistance genes in drinking water treatment plants and distribution systems.

PubMed

Xu, Like; Ouyang, Weiying; Qian, Yanyun; Su, Chao; Su, Jianqiang; Chen, Hong

2016-06-01

Antibiotic resistance genes (ARGs) are present in surface water and often cannot be completely eliminated by drinking water treatment plants (DWTPs). Improper elimination of the ARG-harboring microorganisms contaminates the water supply and would lead to animal and human disease. Therefore, it is of utmost importance to determine the most effective ways by which DWTPs can eliminate ARGs. Here, we tested water samples from two DWTPs and distribution systems and detected the presence of 285 ARGs, 8 transposases, and intI-1 by utilizing high-throughput qPCR. The prevalence of ARGs differed in the two DWTPs, one of which employed conventional water treatments while the other had advanced treatment processes. The relative abundance of ARGs increased significantly after the treatment with biological activated carbon (BAC), raising the number of detected ARGs from 76 to 150. Furthermore, the final chlorination step enhanced the relative abundance of ARGs in the finished water generated from both DWTPs. The total enrichment of ARGs varied from 6.4-to 109.2-fold in tap water compared to finished water, among which beta-lactam resistance genes displayed the highest enrichment. Six transposase genes were detected in tap water samples, with the transposase gene TnpA-04 showing the greatest enrichment (up to 124.9-fold). We observed significant positive correlations between ARGs and mobile genetic elements (MGEs) during the distribution systems, indicating that transposases and intI-1 may contribute to antibiotic resistance in drinking water. To our knowledge, this is the first study to investigate the diversity and abundance of ARGs in drinking water treatment systems utilizing high-throughput qPCR techniques in China. Copyright © 2016 Elsevier Ltd. All rights reserved.

Regression modeling of particle size distributions in urban storm water: advancements through improved sample collection methods

USGS Publications Warehouse

Fienen, Michael N.; Selbig, William R.

2012-01-01

A new sample collection system was developed to improve the representation of sediment entrained in urban storm water by integrating water quality samples from the entire water column. The depth-integrated sampler arm (DISA) was able to mitigate sediment stratification bias in storm water, thereby improving the characterization of suspended-sediment concentration and particle size distribution at three independent study locations. Use of the DISA decreased variability, which improved statistical regression to predict particle size distribution using surrogate environmental parameters, such as precipitation depth and intensity. The performance of this statistical modeling technique was compared to results using traditional fixed-point sampling methods and was found to perform better. When environmental parameters can be used to predict particle size distributions, environmental managers have more options when characterizing concentrations, loads, and particle size distributions in urban runoff.

Legionella - (re-)awakening to the Amoeba-based Pathogens of Distribution System Biofilm

EPA Science Inventory

Fecal pathogens have long been the focus of concern in the distribution of drinking waters. Yet today, with distribution system ‘failures’ accounting for the majority of waterborne outbreaks in the USA, there is growing realization that pathogens endemic to aquatic biofilms may a...

A comprehensive guide for designing more efficient irrigation systems with respect to application control

NASA Astrophysics Data System (ADS)

Khaddam, Issam; Schuetze, Niels

2017-04-01

The worldwide water scarcity problems are expected to aggravate due to the increasing population and the need to produce more food. Irrigated agriculture is considered the highest consumer of fresh water resources with a rate exceeds 70% of global consumption. Consequently, an improvement in the efficiency of all irrigation methods, such as furrow or drip irrigation, becomes more necessary and urgent. Therefore, a more precise knowledge about soil water distribution in the root zone and the water balance components is required. For this purpose and as a part of the SAPHIR project (Saxonian Platform for high Performance Irrigation), a 2D simulation- based study was performed with virtual field conditions. The study investigates the most important design parameters of many irrigation systems, such as irrigation intensity and duration, and shows there influence on the water distribution efficiency. Furthermore, three main soil textures are used to test the impact of the soil hydraulic properties on irrigation effectiveness. A numerous number of irrigation scenarios of each irrigation system was simulated using HYDRUS 2D. Thereafter, the results were digitally calculated, compiled and made available online in the so called "Irrigation Atlases". The irrigation atlases provide graphical results of the soil moisture and pressure head distributions in the root zone. Moreover, they contain detailed information of the water balance for all simulated scenarios. The most studies evaluate the irrigation water demands on local, regional or global scales and for that an efficient water distribution is required. In this context, the irrigation atlases can serve as a valuable tool for the implementation of planned irrigation measures.

Temporal changes in the vertical distribution of flow and chloride in deep wells

USGS Publications Warehouse

Izbicki, John A.; Christensen, Allen H.; Newhouse, Mark W.; Smith, Gregory A.; Hanson, Randall T.

2005-01-01

The combination of flowmeter and depth-dependent water-quality data was used to evaluate the quantity and source of high-chloride water yielded from different depths to eight production wells in the Pleasant Valley area of southern California. The wells were screened from 117 to 437 m below land surface, and in most cases, flow from the aquifer into the wells was not uniformly distributed throughout the well screen. Wells having as little as 6 m of screen in the overlying upper aquifer system yielded as much as 50% of their water from the upper system during drought periods, while the deeper parts of the well screens yielded 15% or less of the total yield of the wells. Mixing of water within wells during pumping degraded higher-quality water with poorer-quality water from deeper depths, and in some cases with poorer-quality water from the overlying upper aquifer system. Changes in the mixture of water within a well, resulting from changes in the distribution of flow into the well, changed the quality of water from the surface discharge of wells over time. The combination of flowmeter and depth-dependent water quality data yielded information about sources of high-chloride water to wells that was not available on the basis of samples collected from nearby observation wells. Changing well design to eliminate small quantities of poor-quality water from deeper parts of the well may improve the quality of water from some wells without greatly reducing well yield. Copyright ?? 2005 National Ground Water Association.

Measuring household consumption and waste in unmetered, intermittent piped water systems

NASA Astrophysics Data System (ADS)

Kumpel, Emily; Woelfle-Erskine, Cleo; Ray, Isha; Nelson, Kara L.

2017-01-01

Measurements of household water consumption are extremely difficult in intermittent water supply (IWS) regimes in low- and middle-income countries, where water is delivered for short durations, taps are shared, metering is limited, and household storage infrastructure varies widely. Nonetheless, consumption estimates are necessary for utilities to improve water delivery. We estimated household water use in Hubli-Dharwad, India, with a mixed-methods approach combining (limited) metered data, storage container inventories, and structured observations. We developed a typology of household water access according to infrastructure conditions based on the presence of an overhead storage tank and a shared tap. For households with overhead tanks, container measurements and metered data produced statistically similar consumption volumes; for households without overhead tanks, stored volumes underestimated consumption because of significant water use directly from the tap during delivery periods. Households that shared taps consumed much less water than those that did not. We used our water use calculations to estimate waste at the household level and in the distribution system. Very few households used 135 L/person/d, the Government of India design standard for urban systems. Most wasted little water even when unmetered, however, unaccounted-for water in the neighborhood distribution systems was around 50%. Thus, conservation efforts should target loss reduction in the network rather than at households.

Simulated effects of ground-water withdrawals and artificial recharge on discharge to streams, springs, and riparian vegetation in the Sierra Vista Subwatershed of the Upper San Pedro Basin, southeastern Arizona

USGS Publications Warehouse

Leake, Stanley A.; Pool, Donald R.; Leenhouts, James M.

2008-01-01

In the context of ground-water resources, “capture” or “streamflow depletion” refers to withdrawal-induced changes in inflow to or outflow from an aquifer. These concepts are helpful in understanding the effects of long-term development of ground-water resources. For the Upper San Pedro Basin in Arizona, USA and Sonora, Mexico, a recently developed ground-water flow model is available to help quantify capture of water from the river and riparian system. A common method of analysis is to compute curves of capture and aquifer-storage change for a range of time at select points of interest. This study, however, presents results of a method to show spatial distributions of total change in inflow and outflow from withdrawal or injection for select times of interest. The mapped areal distributions show the effect of a single well in terms of the ratio of the change in boundary flow rate to rate of withdrawal or injection by the well. To the extent that the system responds linearly to ground-water withdrawal or injection, fractional responses in the mapped distributions can be used to quantify response for any withdrawal or injection rate. Capture distributions calculated using the Upper San Pedro model include response to (1) withdrawal in the lower basin-fill aquifer for times of 10 and 50 years following the initiation of pumping from predevelopment conditions and (2) artificial recharge to the water table in the area underlain by the lower basin-fill aquifer after 10 and 50 years. The mapped distributions show that response to withdrawals and injections is greatest near the river/riparian system. Presence of clay layers in the vertical interval between withdrawal locations and the river/riparian system, however, can delay the response.

Ecology of Legionella pneumophila within water distribution systems.

PubMed Central

Stout, J E; Yu, V L; Best, M G

1985-01-01

The reservoir for hospital-acquired Legionnaires disease has been shown to be the potable water distribution system. We investigated the influence of the natural microbial population and sediment (scale and organic particulates) found in water systems as growth-promoting factors for Legionella pneumophila. Our in vitro experiments showed that: (i) water from hot-water storage tank readily supported the survival of L. pneumophila, (ii) the concentration of sediment was directly related to the survival of L. pneumophila, (iii) the presence of environmental bacteria improved the survival of L. pneumophila via nutritional symbiosis, (iv) the combination of sediment and environmental bacteria acted synergistically to improve the survival of L. pneumophila, and (v) the role of sediment in this synergistic effect was determined to be nutritional. Sediment was found to stimulate the growth of environmental microflora, which in turn stimulated the growth of L. pneumophila. These findings confirm the empiric observations of the predilection of L. pneumophila for growth in hot-water tanks and its localization to sediment. L. pneumophila occupies an ecological niche within the potable water system, with interrelationships between microflora, sediment, and temperature. Images PMID:3977311

The effects of acid precipitation runoff episodes on reservoir and tapwater quality in an Appalachian Mountain water supply.

PubMed Central

Sharpe, W E; DeWalle, D R

1990-01-01

The aluminum concentration and Ryznar Index increased and the pH decreased in a small Appalachian water supply reservoir following acid precipitation runoff episodes. Concomitant increases in tapwater aluminum and decreases in tapwater pH were also observed at two homes in the water distribution system. Lead concentrations in the tapwater of one home frequently exceeded recommended levels, although spatial and temporal variation in tapwater copper and lead concentrations was considerable. Since source water and reservoir water copper and lead concentrations were much lower, the increased copper and lead concentrations in tapwater were attributed to corrosion of household plumbing. Tapwater copper concentration correlated well with tapwater pH and tapwater temperature. Asbestos fibers were not detected in tapwater. The asbestos-cement pipe in the water distribution system was protected by a spontaneous metallic coating that inhibited fiber release from the pipe. Several simultaneous reactions were hypothesized to be taking place in the distribution system that involved corrosion of metallic components and coating of asbestos-cement pipe components in part with corrosion products and in part by cations of watershed origin. Greater water quality changes might be expected in areas of higher atmospheric deposition. Images FIGURE 5. FIGURE 6. PMID:2088742

Drinking Water Microbiome as a Screening Tool for ...

EPA Pesticide Factsheets

Many water utilities in the US using chloramine as disinfectant treatment in their distribution systems have experienced nitrification episodes, which detrimentally impact the water quality. Here, we used 16S rRNA sequencing data to generate high-resolution taxonomic profiles of the bulk water (BW) microbiome from a chloraminated drinking water distribution system (DWDS) simulator. The DWDS was operated through four successive operational schemes, including two stable events (SS) and an episode of nitrification (SF), followed by a ‘chlorine burn’ (SR) by switching disinfectant from chloramine to free chlorine. Specifically, this study focuses on biomarker discovery and their potential use to classify SF episodes. Principal coordinate analysis identified two major clusters (SS and SF; PERMANOVA, p 0.976, p < 0.01). Furthermore, models were able to correctly predict 95% (AUC = 0.983, n = 104) and 96% (AUC = 0.973, n = 72) of samples of the DWDS (community structure of two published studies) and water quality datasets, respectively. The results from this study demonstrate the feasibility of selected BW microbiome signatures as predictive biomarkers of nitrification in DWDS. This new information can be used to optimize current nitrification monitoring plans. The purpose of this research is to add to our knowledge of chloramine and chlorine disinfectants, with regards to effects on the microbial communities in drinking water distribution systems. We used a

REHABILITATION OF AGING WATER INFRASTRUCTURE SYSTEMS: KEY CHALLENGES AND ISSUES

EPA Science Inventory

Presented in this paper are the results of a state-of-the-practice survey on the rehabilitation of water distribution and wastewater collection systems. The survey identified several needs, including the need for rational and common design approaches for rehabilitation systems, ...

Mycobacteria in Water and Loose Deposits of Drinking Water Distribution Systems in Finland

PubMed Central

Torvinen, Eila; Suomalainen, Sini; Lehtola, Markku J.; Miettinen, Ilkka T.; Zacheus, Outi; Paulin, Lars; Katila, Marja-Leena; Martikainen, Pertti J.

2004-01-01

Drinking water distribution systems were analyzed for viable counts of mycobacteria by sampling water from waterworks and in different parts of the systems. In addition, loose deposits collected during mechanical cleaning of the main pipelines were similarly analyzed. The study covered 16 systems at eight localities in Finland. In an experimental study, mycobacterial colonization of biofilms on polyvinyl chloride tubes in a system was studied. The isolation frequency of mycobacteria increased from 35% at the waterworks to 80% in the system, and the number of mycobacteria in the positive samples increased from 15 to 140 CFU/liter, respectively. Mycobacteria were isolated from all 11 deposits with an accumulation time of tens of years and from all 4 deposits which had accumulated during a 1-year follow-up time. The numbers of mycobacteria were high in both old and young deposits (medians, 1.8 × 105 and 3.9 × 105 CFU/g [dry weight], respectively). Both water and deposit samples yielded the highest numbers of mycobacteria in the systems using surface water and applying ozonation as an intermediate treatment or posttreatment. The number and growth of mycobacteria in system waters correlated strongly with the concentration of assimilable organic carbon in the water leaving the waterworks. The densities of mycobacteria in the developing biofilms were highest at the distal sites of the systems. Over 90% of the mycobacteria isolated from water and deposits belonged to Mycobacterium lentiflavum, M. tusciae, M. gordonae, and a previously unclassified group of mycobacteria. Our results indicate that drinking water systems may be a source for recently discovered new mycobacterial species. PMID:15066787

[Effect on iron release in drinking water distribution systems].

PubMed

Niu, Zhang-bin; Wang, Yang; Zhang, Xiao-jian; Chen, Chao; Wang, Sheng-hui

2007-10-01

Batch-scale experiments were done to quantitatively study the effect of inorganic chemical parameters on iron release in drinking water distribution systems. The parameters include acid-base condition, oxidation-reduction condition, and neutral ion condition. It was found that the iron release rate decreased with pH, alkalinity, the concentration of dissolved oxygen increasing, and the iron release rate increased with the concentration of chloride increasing. The theoretical critical formula of iron release rate was elucidated. According to the formula, the necessary condition for controlling iron release is that pH is above 7.6, the concentration of alkalinity and dissolved oxygen is more than 150 mg/L and 2 mg/L, and the concentration of chloride is less than 150 mg/L of distributed water.

Effects of contrasting rooting distribution patterns on plant transpiration along a precipitation gradient

USDA-ARS?s Scientific Manuscript database

Understanding and predicting ecosystem functioning in water limited ecosystems requires a thorough assessment of the role plant root systems. Widespread ecological phenomena such as shrub encroachment may drastically change root distribution in the soil profile affecting the uptake of water and nutr...

[Microorganisms surviving in drinking water systems and related problems].

PubMed

Aulicino, F A; Pastoni, F

2004-01-01

Drinking water in distribution systems may show abnormal values of some parameters, such as turbidity, and may support particular phenomena, such as bacterial regrowth or presence of Viable Not Culturable (VNC) bacteria. Turbidity can provide shelter for opportunistic microorganisms and pathogens. The Milwaukee outbreak (400,000 people) is one example of waterborne disease caused by the presence of pathogens (Cryptosporidium) in drinking water characterized by high and intermittent levels of turbidity. Bacterial regrowth in drinking water distribution systems may cause high increments of microorganisms such as heterotrophic bacteria, coliforms and pathogens. Microorganisms isolated from biofilm including Pseudomonas, Aeromonas, Legionella may have a significant health hazard especially in hospital areas. The presence of VNC bacteria in drinking water may represent a problem for their discussed role in infectious diseases, but also for the possibility of a considerable underestimation of true microbial concentrations in drinking waters. To study this kind of problems is necessary to apply suitable methods for drinking water analyses.

Water Supply Systems For Aircraft Fire And Rescue Protection

DOT National Transportation Integrated Search

1995-01-01

This Advisory Circular (AC) provides guidance for the selection : of a water source and standards for the design of a distribution system to : support aircraft rescue and fire fighting (ARFF) service operations on : airports.

Improved simulation of river water and groundwater exchange in an alluvial plain using the SWAT model

USDA-ARS?s Scientific Manuscript database

Hydrological interaction between surface and subsurface water systems has a significant impact on water quality, ecosystems and biogeochemistry cycling of both systems. Distributed models have been developed to simulate this function, but they require detailed spatial inputs and extensive computati...

EVALUATION OF WATER MONITORING INSTRUMENTATION AT EPA'S WATER AWARENESS TECHNOLOGY EVALUATION RESEARCH SECURITY CENTER

EPA Science Inventory

The safety and security of distribution systems has come under reassessment in the past year. Several chemical and biological agents have been identified that might constitute a credible threat against water supply systems. There have also been a few reported threats against wate...

Dual Water Systems: Characterization and Performance for Distribution of Reclaimed Water (WaterRF Report 4333)

EPA Science Inventory

The research tasks included: an inventory of cases where dual systems have been implemented; formulation of a protocol to identify claimed benefits, costs, and risks; collection of data (quantitative and anecdotal) to assess performance; display of data in the form of performance...

WATER QUALITY IN SOURCE WATER, TREATMENT, AND DISTRIBUTION SYSTEMS

EPA Science Inventory

Most drinking water utilities practice the multiple-barrier concept as the guiding principle for providing safe water. This chapter discusses multiple barriers as they relate to the basic criteria for selecting and protecting source waters, including known and potential sources ...

Benefits of Genomic Insights and CRISPR-Cas Signatures to Monitor Potential Pathogens across Drinking Water Production and Distribution Systems

PubMed Central

Zhang, Ya; Kitajima, Masaaki; Whittle, Andrew J.; Liu, Wen-Tso

2017-01-01

The occurrence of pathogenic bacteria in drinking water distribution systems (DWDSs) is a major health concern, and our current understanding is mostly related to pathogenic species such as Legionella pneumophila and Mycobacterium avium but not to bacterial species closely related to them. In this study, genomic-based approaches were used to characterize pathogen-related species in relation to their abundance, diversity, potential pathogenicity, genetic exchange, and distribution across an urban drinking water system. Nine draft genomes recovered from 10 metagenomes were identified as Legionella (4 draft genomes), Mycobacterium (3 draft genomes), Parachlamydia (1 draft genome), and Leptospira (1 draft genome). The pathogenicity potential of these genomes was examined by the presence/absence of virulence machinery, including genes belonging to Type III, IV, and VII secretion systems and their effectors. Several virulence factors known to pathogenic species were detected with these retrieved draft genomes except the Leptospira-related genome. Identical clustered regularly interspaced short palindromic repeats-CRISPR-associated proteins (CRISPR-Cas) genetic signatures were observed in two draft genomes recovered at different stages of the studied system, suggesting that the spacers in CRISPR-Cas could potentially be used as a biomarker in the monitoring of Legionella related strains at an evolutionary scale of several years across different drinking water production and distribution systems. Overall, metagenomics approach was an effective and complementary tool of culturing techniques to gain insights into the pathogenic characteristics and the CRISPR-Cas signatures of pathogen-related species in DWDSs. PMID:29097994

Hydraulics for Operators. Training Module 1.330.2.77.

ERIC Educational Resources Information Center

Bengston, Harlan H.

This document is an instructional module package prepared in objective form for use by an instructor familiar with the application of hydraulic principles for operation and maintenance of water supply systems, water distribution systems, wastewater treatment systems and wastewater collection systems. Included are objectives, instructor guides,…

Performance test for a solar water heater

NASA Technical Reports Server (NTRS)

1979-01-01

Two reports describe procedures and results of performance tests on domestic solar powered hot water system. Performance tests determine amount of energy collected by system, amount of energy delivered to solar source, power required to operate system and maintain proper tank temperature, overall system efficiency, and temperature distribution in tank.

Inactivation of bacterial biothreat agents in water, a review.

PubMed

Rose, L J; Rice, E W

2014-12-01

Water supplies and water distribution systems have been identified as potential targets for contamination by bacterial biothreat agents. Since the 2001 Bacillus anthracis bioterrorist attacks, additional efforts have been aimed at research to characterize biothreat organisms in regards to their susceptibility to disinfectants and technologies currently in use for potable water. Here, we present a review of research relevant to disinfection of bacteria with the potential to pose a severe threat to public health and safety, and their potential surrogates. The efficacy of chlorine, monochloramine, chlorine dioxide, and ultraviolet light to inactivate each organism in suspension is described. The complexities of disinfection under varying water conditions and when the organisms are associated with biofilms in distribution systems are discussed.

Evaluating the risk of water distribution system failure: A shared frailty model

NASA Astrophysics Data System (ADS)

Clark, Robert M.; Thurnau, Robert C.

2011-12-01

Condition assessment (CA) Modeling is drawing increasing interest as a technique that can assist in managing drinking water infrastructure. This paper develops a model based on the application of a Cox proportional hazard (PH)/shared frailty model and applies it to evaluating the risk of failure in drinking water networks using data from the Laramie Water Utility (located in Laramie, Wyoming, USA). Using the risk model a cost/ benefit analysis incorporating the inspection value method (IVM), is used to assist in making improved repair, replacement and rehabilitation decisions for selected drinking water distribution system pipes. A separate model is developed to predict failures in prestressed concrete cylinder pipe (PCCP). Various currently available inspection technologies are presented and discussed.

Inactivation of bacterial biothreat agents in water, a review

PubMed Central

Rice, E. W.

2016-01-01

Water supplies and water distribution systems have been identified as potential targets for contamination by bacterial biothreat agents. Since the 2001 Bacillus anthracis bioterrorist attacks, additional efforts have been aimed at research to characterize biothreat organisms in regards to their susceptibility to disinfectants and technologies currently in use for potable water. Here, we present a review of research relevant to disinfection of bacteria with the potential to pose a severe threat to public health and safety, and their potential surrogates. The efficacy of chlorine, monochloramine, chlorine dioxide, and ultraviolet light to inactivate each organism in suspension is described. The complexities of disinfection under varying water conditions and when the organisms are associated with biofilms in distribution systems are discussed. PMID:25473971

Redox gradients in distribution systems influence water quality, corrosion, and microbial ecology.

PubMed

Masters, Sheldon; Wang, Hong; Pruden, Amy; Edwards, Marc A

2015-01-01

Simulated distribution systems (SDSs) defined the interplay between disinfectant type (free chlorine and chloramines), water age (1-10.2 days), and pipe material (PVC, iron and cement surfaces) on water chemistry, redox zones and infrastructure degradation. Redox gradients developed as a function of water age and pipe material affected the quality of water consumers would receive. Free chlorine was most stable in the presence of PVC while chloramine was most stable in the presence of cement. At a 3.6 day water age the residual in the chlorinated PVC SDS was more than 3.5 times higher than in the chlorinated iron or cement systems. In contrast, the residual in the chloraminated cement SDS was more than 10 times greater than in the chloraminated iron or PVC systems. Near the point of entry to the SDSs where disinfectant residuals were present, free chlorine tended to cause as much as 4 times more iron corrosion when compared to chloramines. Facultative denitrifying bacteria were ubiquitous, and caused complete loss of nitrogen at distal points in systems with iron, and these bacteria co-occurred with very severe pitting attack (1.6-1.9 mm/year) at high water age.

Optimization of pressure gauge locations for water distribution systems using entropy theory.

PubMed

Yoo, Do Guen; Chang, Dong Eil; Jun, Hwandon; Kim, Joong Hoon

2012-12-01

It is essential to select the optimal pressure gauge location for effective management and maintenance of water distribution systems. This study proposes an objective and quantified standard for selecting the optimal pressure gauge location by defining the pressure change at other nodes as a result of demand change at a specific node using entropy theory. Two cases are considered in terms of demand change: that in which demand at all nodes shows peak load by using a peak factor and that comprising the demand change of the normal distribution whose average is the base demand. The actual pressure change pattern is determined by using the emitter function of EPANET to reflect the pressure that changes practically at each node. The optimal pressure gauge location is determined by prioritizing the node that processes the largest amount of information it gives to (giving entropy) and receives from (receiving entropy) the whole system according to the entropy standard. The suggested model is applied to one virtual and one real pipe network, and the optimal pressure gauge location combination is calculated by implementing the sensitivity analysis based on the study results. These analysis results support the following two conclusions. Firstly, the installation priority of the pressure gauge in water distribution networks can be determined with a more objective standard through the entropy theory. Secondly, the model can be used as an efficient decision-making guide for gauge installation in water distribution systems.

ANALYTICAL EQUATIONS OF STORAGE RESERVOIR WATER QUALITY

EPA Science Inventory

Distribution system water quality protection is an integral aspect of public water supply management. Effective regulatory compliance requires a thorough understanding of the transport and mixing processes in storage reservoirs and their impacts on effluent water quality. This ...

Molecular dynamics approach to water structure of HII mesophase of monoolein

NASA Astrophysics Data System (ADS)

Kolev, Vesselin; Ivanova, Anela; Madjarova, Galia; Aserin, Abraham; Garti, Nissim

2012-02-01

The goal of the present work is to study theoretically the structure of water inside the water cylinder of the inverse hexagonal mesophase (HII) of glyceryl monooleate (monoolein, GMO), using the method of molecular dynamics. To simplify the computational model, a fixed structure of the GMO tube is maintained. The non-standard cylindrical geometry of the system required the development and application of a novel method for obtaining the starting distribution of water molecules. A predictor-corrector schema is employed for generation of the initial density of water. Molecular dynamics calculations are performed at constant volume and temperature (NVT ensemble) with 1D periodic boundary conditions applied. During the simulations the lipid structure is kept fixed, while the dynamics of water is unrestrained. Distribution of hydrogen bonds and density as well as radial distribution of water molecules across the water cylinder show the presence of water structure deep in the cylinder (about 6 Å below the GMO heads). The obtained results may help understanding the role of water structure in the processes of insertion of external molecules inside the GMO/water system. The present work has a semi-quantitative character and it should be considered as the initial stage of more comprehensive future theoretical studies.

Comparison of Particle-Associated Bacteria from a Drinking Water Treatment Plant and Distribution Reservoirs with Different Water Sources

PubMed Central

Liu, G.; Ling, F. Q.; van der Mark, E. J.; Zhang, X. D.; Knezev, A.; Verberk, J. Q. J. C.; van der Meer, W. G. J.; Medema, G. J.; Liu, W. T.; van Dijk, J. C.

2016-01-01

This study assessed the characteristics of and changes in the suspended particles and the associated bacteria in an unchlorinated drinking water distribution system and its reservoirs with different water sources. The results show that particle-associated bacteria (PAB) were present at a level of 0.8–4.5 × 103 cells ml−1 with a biological activity of 0.01–0.04 ng l−1 ATP. Different PAB communities in the waters produced from different sources were revealed by a 16S rRNA-based pyrosequencing analysis. The quantified biomass underestimation due to the multiple cells attached per particle was ≥ 85%. The distribution of the biologically stable water increased the number of cells per particle (from 48 to 90) but had minor effects on the PAB community. Significant changes were observed at the mixing reservoir. Our results show the characteristics of and changes in suspended PAB during distribution, and highlight the significance of suspended PAB in the distribution system, because suspended PAB can lead to a considerable underestimation of biomass, and because they exist as biofilm, which has a greater mobility than pipe-wall biofilm and therefore presents a greater risk, given the higher probability that it will reach the customers’ taps and be ingested. PMID:26832989

[Effects of submarine topography and water depth on distribution of pelagic fish community in minnan-taiwan bank fishing ground].

PubMed

Fang, Shuimei; Yang, Shengyun; Zhang, Chengmao; Zhu, Jinfu

2002-11-01

According to the fishing record of the light-seine information vessel in Minnan-Taiwan bank ground during 1989 to 1999, the effects of submarine topography and water depth on distribution of pelagic fish community in Minnan-Taiwan bank fishing ground was studied. The results showed that the pelagic fish distributed concentratively, while the submarine topography and water depth varied widely, but in different fishing regions, the distribution of pelagic fishes was uneven. The distribution of fishing yield increased from north to south, and closed up from sides of the bank to south or north in the regions. Pelagic fish distributed mainly in mixed water in the southern Taiwan Strait, and in warm water in the Taiwan Strait. The central fishing grounds were at high salt regions. Close gathering regions of pelagic fish or central fishing ground would be varied with the seasonal variation of mixed water in the southern Taiwan Strait and warm water in the Taiwan Strait. Central fishing ground was not only related to submarine topography and water depth, but also related to wind direction, wind-power and various water systems. In the fishing ground, the gathering depth of pelagic fish was 30-60 m in spring and summer, and 40-80 m in autumn and winter.

Improved mine blast algorithm for optimal cost design of water distribution systems

NASA Astrophysics Data System (ADS)

Sadollah, Ali; Guen Yoo, Do; Kim, Joong Hoon

2015-12-01

The design of water distribution systems is a large class of combinatorial, nonlinear optimization problems with complex constraints such as conservation of mass and energy equations. Since feasible solutions are often extremely complex, traditional optimization techniques are insufficient. Recently, metaheuristic algorithms have been applied to this class of problems because they are highly efficient. In this article, a recently developed optimizer called the mine blast algorithm (MBA) is considered. The MBA is improved and coupled with the hydraulic simulator EPANET to find the optimal cost design for water distribution systems. The performance of the improved mine blast algorithm (IMBA) is demonstrated using the well-known Hanoi, New York tunnels and Balerma benchmark networks. Optimization results obtained using IMBA are compared to those using MBA and other optimizers in terms of their minimum construction costs and convergence rates. For the complex Balerma network, IMBA offers the cheapest network design compared to other optimization algorithms.

Simulations and field observations of root water uptake in plots with different soil water availability.

NASA Astrophysics Data System (ADS)

Cai, Gaochao; Vanderborght, Jan; Couvreur, Valentin; Javaux, Mathieu; Vereecken, Harry

2015-04-01

Root water uptake is a main process in the hydrological cycle and vital for water management in agronomy. In most models of root water uptake, the spatial and temporal soil water status and plant root distributions are required for water flow simulations. However, dynamic root growth and root distributions are not easy and time consuming to measure by normal approaches. Furthermore, root water uptake cannot be measured directly in the field. Therefore, it is necessary to incorporate monitoring data of soil water content and potential and root distributions within a modeling framework to explore the interaction between soil water availability and root water uptake. But, most models are lacking a physically based concept to describe water uptake from soil profiles with vertical variations in soil water availability. In this contribution, we present an experimental setup in which root development, soil water content and soil water potential are monitored non-invasively in two field plots with different soil texture and for three treatments with different soil water availability: natural rain, sheltered and irrigated treatment. Root development is monitored using 7-m long horizontally installed minirhizotubes at six depths with three replicates per treatment. The monitoring data are interpreted using a model that is a one-dimensional upscaled version of root water uptake model that describes flow in the coupled soil-root architecture considering water potential gradients in the system and hydraulic conductances of the soil and root system (Couvreur et al., 2012). This model approach links the total root water uptake to an effective soil water potential in the root zone. The local root water uptake is a function of the difference between the local soil water potential and effective root zone water potential so that compensatory uptake in heterogeneous soil water potential profiles is simulated. The root system conductance is derived from inverse modelling using measurements of soil water potentials, water contents, and root distributions. The results showed that this modelling approach reproduced soil water dynamics well in the different plots and treatments. Root water uptake reduced when the effective soil water potential decreased to around -70 to -100 kPa in the root zone. Couvreur, V., Vanderborght, J., and Javaux, M.: A simple three dimensional macroscopic root water uptake model based on the hydraulic architecture approach, Hydrol. Earth Syst. Sci., 16, 2957-2971, doi:10.5194/hess-16-2957-2012, 2012.

Distribution of trace metals in the vicinity of a wastewater treatment plant on the Potomac River, Washington, DC, USA

NASA Astrophysics Data System (ADS)

Smith, J. P.; Muller, A. C.

2013-05-01

Predicting the fate and distribution of anthropogenic-sourced trace metals in riverine and estuarine systems is challenging due to multiple and varying source functions and dynamic physiochemical conditions. Between July 2011 and November 2012, sediment and water column samples were collected from over 20 sites in the tidal-fresh Potomac River estuary, Washington, DC near the outfall of the Blue Plains Advanced Wastewater Treatment Plant (BPWTP) for measurement of select trace metals. Field observations of water column parameters (conductivity, temperature, pH, turbidity) were also made at each sampling site. Trace metal concentrations were normalized to the "background" composition of the river determined from control sites in order to investigate the distribution BPWTP-sourced in local Potomac River receiving waters. Temporal differences in the observed distribution of trace metals were attributed to changes in the relative contribution of metals from different sources (wastewater, riverine, other) coupled with differences in the physiochemical conditions of the water column. Results show that normalizing near-source concentrations to the background composition of the water body and also to key environmental parameters can aid in predicting the fate and distribution of anthropogenic-sourced trace metals in dynamic riverine and estuarine systems like the tidal-fresh Potomac River.

Rehabilitation of Wastewater Collection and Water Distribution Systems

EPA Science Inventory

The nation’s 54,000 drinking water systems and 16,000 wastewater systems are nearing the end of their useful life and need to be replaced/repaired to comply with federal regulations. Rehabilitation includes a broad spectrum of approaches, from repair to replacement that attempt ...

On the probabilistic structure of water age

NASA Astrophysics Data System (ADS)

Porporato, Amilcare; Calabrese, Salvatore

2015-05-01

The age distribution of water in hydrologic systems has received renewed interest recently, especially in relation to watershed response to rainfall inputs. The purpose of this contribution is first to draw attention to existing theories of age distributions in population dynamics, fluid mechanics and stochastic groundwater, and in particular to the McKendrick-von Foerster equation and its generalizations and solutions. A second and more important goal is to clarify that, when hydrologic fluxes are modeled by means of time-varying stochastic processes, the age distributions must themselves be treated as random functions. Once their probabilistic structure is obtained, it can be used to characterize the variability of age distributions in real systems and thus help quantify the inherent uncertainty in the field determination of water age. We illustrate these concepts with reference to a stochastic storage model, which has been used as a minimalist model of soil moisture and streamflow dynamics.

MODELING CHLORINE RESIDUALS IN DRINKING-WATER DISTRIBUTION SYSTEMS

EPA Science Inventory

A mass-transfer-based model is developed for predicting chlorine decay in drinking-water distribution networks. The model considers first-order reactions of chlorine to occur both in the bulk flow and at the pipe wall. The overall rate of the wall reaction is a function of the ...

MODELING CHLORINE RESIDUALS IN DRINKING-WATER DISTRIBUTION SYSTEMS

EPA Science Inventory

A mass transfer-based model is developed for predicting chlorine decay in drinking water distribution networks. he model considers first order reactions of chlorine to occur both in the bulk flow and at the pipe wall. he overall rate of the wall reaction is a function of the rate...

Characterization and release profile of (Mn, Al)-bearing deposits in drinking water distribution systems.

PubMed

Li, Guiwei; Ding, Yuanxun; Xu, Hongfu; Jin, Junwei; Shi, Baoyou

2018-04-01

Inorganic contaminants accumulation in drinking water distribution systems (DWDS) is a great threat to water quality and safety. This work assessed the main risk factors for different water pipes and discovered the release profile of accumulated materials in a full scale distribution system frequently suffered from water discoloration problem. Physicochemical characterization of pipe deposits were performed using X-ray fluorescence, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The metal release profile was obtained through continuous monitoring of a full-scale DWDS area. The results showed that aluminum and manganese were the main metals of deposits in nonmetallic pipes, while iron was dominant in iron-based pipe corrosion scales. Manganese primarily existed as MnO 2 without well crystalline form. The relative abundance of Mn and Fe in deposits changed with their distance from the water treatment plant. Compared with iron in corrosion scales, Mn and Al were more labile to be released back into bulk water during unidirectional flushing process. A main finding of this work is the co-release behavior of Mn and Al in particulate form and significant correlation exists between these two metals. Dual control of manganese and aluminum in treated water is proposed to be essential to cope with discoloration and trace metal contamination in DWDS. Copyright © 2018 Elsevier Ltd. All rights reserved.

Core-satellite populations and seasonality of water meter biofilms in a metropolitan drinking water distribution system

PubMed Central

Ling, Fangqiong; Hwang, Chiachi; LeChevallier, Mark W; Andersen, Gary L; Liu, Wen-Tso

2016-01-01

Drinking water distribution systems (DWDSs) harbor the microorganisms in biofilms and suspended communities, yet the diversity and spatiotemporal distribution have been studied mainly in the suspended communities. This study examined the diversity of biofilms in an urban DWDS, its relationship with suspended communities and its dynamics. The studied DWDS in Urbana, Illinois received conventionally treated and disinfected water sourced from the groundwater. Over a 2-year span, biomass were sampled from household water meters (n=213) and tap water (n=20) to represent biofilm and suspended communities, respectively. A positive correlation between operational taxonomic unit (OTU) abundance and occupancy was observed. Examined under a ‘core-satellite' model, the biofilm community comprised 31 core populations that encompassed 76.7% of total 16 S rRNA gene pyrosequences. The biofilm communities shared with the suspended community highly abundant and prevalent OTUs, which related to methano-/methylotrophs (i.e., Methylophilaceae and Methylococcaceae) and aerobic heterotrophs (Sphingomonadaceae and Comamonadaceae), yet differed by specific core populations and lower diversity and evenness. Multivariate tests indicated seasonality as the main contributor to community structure variation. This pattern was resilient to annual change and correlated to the cyclic fluctuations of core populations. The findings of a distinctive biofilm community assemblage and methano-/methyltrophic primary production provide critical insights for developing more targeted water quality monitoring programs and treatment strategies for groundwater-sourced drinking water systems. PMID:26251872

Core-satellite populations and seasonality of water meter biofilms in a metropolitan drinking water distribution system.

PubMed

Ling, Fangqiong; Hwang, Chiachi; LeChevallier, Mark W; Andersen, Gary L; Liu, Wen-Tso

2016-03-01

Drinking water distribution systems (DWDSs) harbor the microorganisms in biofilms and suspended communities, yet the diversity and spatiotemporal distribution have been studied mainly in the suspended communities. This study examined the diversity of biofilms in an urban DWDS, its relationship with suspended communities and its dynamics. The studied DWDS in Urbana, Illinois received conventionally treated and disinfected water sourced from the groundwater. Over a 2-year span, biomass were sampled from household water meters (n=213) and tap water (n=20) to represent biofilm and suspended communities, respectively. A positive correlation between operational taxonomic unit (OTU) abundance and occupancy was observed. Examined under a 'core-satellite' model, the biofilm community comprised 31 core populations that encompassed 76.7% of total 16 S rRNA gene pyrosequences. The biofilm communities shared with the suspended community highly abundant and prevalent OTUs, which related to methano-/methylotrophs (i.e., Methylophilaceae and Methylococcaceae) and aerobic heterotrophs (Sphingomonadaceae and Comamonadaceae), yet differed by specific core populations and lower diversity and evenness. Multivariate tests indicated seasonality as the main contributor to community structure variation. This pattern was resilient to annual change and correlated to the cyclic fluctuations of core populations. The findings of a distinctive biofilm community assemblage and methano-/methyltrophic primary production provide critical insights for developing more targeted water quality monitoring programs and treatment strategies for groundwater-sourced drinking water systems.

Understanding Microplastic Distribution: A Global Citizen Monitoring Effort

NASA Astrophysics Data System (ADS)

Barrows, A.

2016-02-01

Understanding distribution and abundance of microplastics in the world's oceans will continue to help inform global law-making. Through recruiting and training over 500 volunteers our study has collected over 1000 samples from remote and populated areas world-wide. Samples include water collected at the sea surface and throughout the water column. Surface to depth sampling has provided insight into vertical plastic distribution. The development of unique field and laboratory methodology has enabled plastics to be quantified down to 50 µm. In 2015, the study expanded to include global freshwater systems. By understanding plastic patterns, distribution and concentration in large and small watersheds we will better understand how freshwater systems are contributing to marine microplastic pollution.

Using a GIS to link digital spatial data and the precipitation-runoff modeling system, Gunnison River Basin, Colorado

USGS Publications Warehouse

Battaglin, William A.; Kuhn, Gerhard; Parker, Randolph S.

1993-01-01

The U.S. Geological Survey Precipitation-Runoff Modeling System, a modular, distributed-parameter, watershed-modeling system, is being applied to 20 smaller watersheds within the Gunnison River basin. The model is used to derive a daily water balance for subareas in a watershed, ultimately producing simulated streamflows that can be input into routing and accounting models used to assess downstream water availability under current conditions, and to assess the sensitivity of water resources in the basin to alterations in climate. A geographic information system (GIS) is used to automate a method for extracting physically based hydrologic response unit (HRU) distributed parameter values from digital data sources, and for the placement of those estimates into GIS spatial datalayers. The HRU parameters extracted are: area, mean elevation, average land-surface slope, predominant aspect, predominant land-cover type, predominant soil type, average total soil water-holding capacity, and average water-holding capacity of the root zone.

Establishment of HPC(R2A) for regrowth control in non-chlorinated distribution systems.

PubMed

Uhl, Wolfgang; Schaule, Gabriela

2004-05-01

Drinking water distributed without disinfection and without regrowth problems for many years may show bacterial regrowth when the residence time and/or temperature in the distribution system increases or when substrate and/or bacterial concentration in the treated water increases. An example of a regrowth event in a major German city is discussed. Regrowth of HPC bacteria occurred unexpectedly at the end of a very hot summer. No pathogenic or potentially pathogenic bacteria were identified. Increased residence times in the distribution system and temperatures up to 25 degrees C were identified as most probable causes and the regrowth event was successfully overcome by changing flow regimes and decreasing residence times. Standard plate counts of HPC bacteria using the spread plate technique on nutrient rich agar according to German Drinking Water Regulations (GDWR) had proven to be a very good indicator of hygienically safe drinking water and to demonstrate the effectiveness of water treatment. However, the method proved insensitive for early regrowth detection. Regrowth experiments in the lab and sampling of the distribution system during two summers showed that spread plate counts on nutrient-poor R2A agar after 7-day incubation yielded 100 to 200 times higher counts. Counts on R2A after 3-day incubation were three times less than after 7 days. As the precision of plate count methods is very poor for counts less than 10 cfu/plate, a method yielding higher counts is better suited to detect upcoming regrowth than a method yielding low counts. It is shown that for the identification of regrowth events HPC(R2A) gives a further margin of about 2 weeks for reaction before HPC(GDWR). Copyright 2003 Elsevier B.V.

In-pipe water quality monitoring in water supply systems under steady and unsteady state flow conditions: a quantitative assessment.

PubMed

Aisopou, Angeliki; Stoianov, Ivan; Graham, Nigel J D

2012-01-01

Monitoring the quality of drinking water from the treatment plant to the consumers tap is critical to ensure compliance with national standards and/or WHO guideline levels. There are a number of processes and factors affecting the water quality during transmission and distribution which are little understood. A significant obstacle for gaining a detailed knowledge of various physical and chemical processes and the effect of the hydraulic conditions on the water quality deterioration within water supply systems is the lack of reliable and low-cost (both capital and O & M) water quality sensors for continuous monitoring. This paper has two objectives. The first one is to present a detailed evaluation of the performance of a novel in-pipe multi-parameter sensor probe for reagent- and membrane-free continuous water quality monitoring in water supply systems. The second objective is to describe the results from experimental research which was conducted to acquire continuous water quality and high-frequency hydraulic data for the quantitative assessment of the water quality changes occurring under steady and unsteady-state flow conditions. The laboratory and field evaluation of the multi-parameter sensor probe showed that the sensors have a rapid dynamic response, average repeatability and unreliable accuracy. The uncertainties in the sensor data present significant challenges for the analysis and interpretation of the acquired data and their use for water quality modelling, decision support and control in operational systems. Notwithstanding these uncertainties, the unique data sets acquired from transmission and distribution systems demonstrated the deleterious effect of unsteady state flow conditions on various water quality parameters. These studies demonstrate: (i) the significant impact of the unsteady-state hydraulic conditions on the disinfectant residual, turbidity and colour caused by the re-suspension of sediments, scouring of biofilms and tubercles from the pipe and increased mixing, and the need for further experimental research to investigate these interactions; (ii) important advances in sensor technologies which provide unique opportunities to study both the dynamic hydraulic conditions and water quality changes in operational systems. The research in these two areas is critical to better understand and manage the water quality deterioration in ageing water transmission and distribution systems. Copyright © 2011 Elsevier Ltd. All rights reserved.

Flow Cytometry Total Cell Counts: A Field Study Assessing Microbiological Water Quality and Growth in Unchlorinated Drinking Water Distribution Systems

PubMed Central

Liu, G.; Van der Mark, E. J.; Verberk, J. Q. J. C.; Van Dijk, J. C.

2013-01-01

The objective of this study was to evaluate the application of flow cytometry total cell counts (TCCs) as a parameter to assess microbial growth in drinking water distribution systems and to determine the relationships between different parameters describing the biostability of treated water. A one-year sampling program was carried out in two distribution systems in The Netherlands. Results demonstrated that, in both systems, the biomass differences measured by ATP were not significant. TCC differences were also not significant in treatment plant 1, but decreased slightly in treatment plant 2. TCC values were found to be higher at temperatures above 15°C than at temperatures below 15°C. The correlation study of parameters describing biostability found no relationship among TCC, heterotrophic plate counts, and Aeromonas. Also no relationship was found between TCC and ATP. Some correlation was found between the subgroup of high nucleic acid content bacteria and ATP (R 2 = 0.63). Overall, the results demonstrated that TCC is a valuable parameter to assess the drinking water biological quality and regrowth; it can directly and sensitively quantify biomass, detect small changes, and can be used to determine the subgroup of active HNA bacteria that are related to ATP. PMID:23819117

Diverse manganese(II)-oxidizing bacteria are prevalent in drinking water systems.

PubMed

Marcus, Daniel N; Pinto, Ameet; Anantharaman, Karthik; Ruberg, Steven A; Kramer, Eva L; Raskin, Lutgarde; Dick, Gregory J

2017-04-01

Manganese (Mn) oxides are highly reactive minerals that influence the speciation, mobility, bioavailability and toxicity of a wide variety of organic and inorganic compounds. Although Mn(II)-oxidizing bacteria are known to catalyze the formation of Mn oxides, little is known about the organisms responsible for Mn oxidation in situ, especially in engineered environments. Mn(II)-oxidizing bacteria are important in drinking water systems, including in biofiltration and water distribution systems. Here, we used cultivation dependent and independent approaches to investigate Mn(II)-oxidizing bacteria in drinking water sources, a treatment plant and associated distribution system. We isolated 29 strains of Mn(II)-oxidizing bacteria and found that highly similar 16S rRNA gene sequences were present in all culture-independent datasets and dominant in the studied drinking water treatment plant. These results highlight a potentially important role for Mn(II)-oxidizing bacteria in drinking water systems, where biogenic Mn oxides may affect water quality in terms of aesthetic appearance, speciation of metals and oxidation of organic and inorganic compounds. Deciphering the ecology of these organisms and the factors that regulate their Mn(II)-oxidizing activity could yield important insights into how microbial communities influence the quality of drinking water. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

Modelling transient temperature distribution for injecting hot water through a well to an aquifer thermal energy storage system

NASA Astrophysics Data System (ADS)

Yang, Shaw-Yang; Yeh, Hund-Der; Li, Kuang-Yi

2010-10-01

Heat storage systems are usually used to store waste heat and solar energy. In this study, a mathematical model is developed to predict both the steady-state and transient temperature distributions of an aquifer thermal energy storage (ATES) system after hot water is injected through a well into a confined aquifer. The ATES has a confined aquifer bounded by aquicludes with different thermomechanical properties and geothermal gradients along the depth. Consider that the heat is transferred by conduction and forced convection within the aquifer and by conduction within the aquicludes. The dimensionless semi-analytical solutions of temperature distributions of the ATES system are developed using Laplace and Fourier transforms and their corresponding time-domain results are evaluated numerically by the modified Crump method. The steady-state solution is obtained from the transient solution through the final-value theorem. The effect of the heat transfer coefficient on aquiclude temperature distribution is appreciable only near the outer boundaries of the aquicludes. The present solutions are useful for estimating the temperature distribution of heat injection and the aquifer thermal capacity of ATES systems.

GIS model-based real-time hydrological forecasting and operation management system for the Lake Balaton and its watershed

NASA Astrophysics Data System (ADS)

Adolf Szabó, János; Zoltán Réti, Gábor; Tóth, Tünde

2017-04-01

Today, the most significant mission of the decision makers on integrated water management issues is to carry out sustainable management for sharing the resources between a variety of users and the environment under conditions of considerable uncertainty (such as climate/land-use/population/etc. change) conditions. In light of this increasing water management complexity, we consider that the most pressing needs is to develop and implement up-to-date GIS model-based real-time hydrological forecasting and operation management systems for aiding decision-making processes to improve water management. After years of researches and developments the HYDROInform Ltd. has developed an integrated, on-line IT system (DIWA-HFMS: DIstributed WAtershed - Hydrologyc Forecasting & Modelling System) which is able to support a wide-ranging of the operational tasks in water resources management such as: forecasting, operation of lakes and reservoirs, water-control and management, etc. Following a test period, the DIWA-HFMS has been implemented for the Lake Balaton and its watershed (in 500 m resolution) at Central-Transdanubian Water Directorate (KDTVIZIG). The significant pillars of the system are: - The DIWA (DIstributed WAtershed) hydrologic model, which is a 3D dynamic water-balance model that distributed both in space and its parameters, and which was developed along combined principles but its mostly based on physical foundations. The DIWA integrates 3D soil-, 2D surface-, and 1D channel-hydraulic components as well. - Lakes and reservoir-operating component; - Radar-data integration module; - fully online data collection tools; - scenario manager tool to create alternative scenarios, - interactive, intuitive, highly graphical user interface. In Vienna, the main functions, operations and results-management of the system will be presented.

Multiobjective optimization of cluster-scale urban water systems investigating alternative water sources and level of decentralization

NASA Astrophysics Data System (ADS)

Newman, J. P.; Dandy, G. C.; Maier, H. R.

2014-10-01

In many regions, conventional water supplies are unable to meet projected consumer demand. Consequently, interest has arisen in integrated urban water systems, which involve the reclamation or harvesting of alternative, localized water sources. However, this makes the planning and design of water infrastructure more difficult, as multiple objectives need to be considered, water sources need to be selected from a number of alternatives, and end uses of these sources need to be specified. In addition, the scale at which each treatment, collection, and distribution network should operate needs to be investigated. In order to deal with this complexity, a framework for planning and designing water infrastructure taking into account integrated urban water management principles is presented in this paper and applied to a rural greenfield development. Various options for water supply, and the scale at which they operate were investigated in order to determine the life-cycle trade-offs between water savings, cost, and GHG emissions as calculated from models calibrated using Australian data. The decision space includes the choice of water sources, storage tanks, treatment facilities, and pipes for water conveyance. For each water system analyzed, infrastructure components were sized using multiobjective genetic algorithms. The results indicate that local water sources are competitive in terms of cost and GHG emissions, and can reduce demand on the potable system by as much as 54%. Economies of scale in treatment dominated the diseconomies of scale in collection and distribution of water. Therefore, water systems that connect large clusters of households tend to be more cost efficient and have lower GHG emissions. In addition, water systems that recycle wastewater tended to perform better than systems that captured roof-runoff. Through these results, the framework was shown to be effective at identifying near optimal trade-offs between competing objectives, thereby enabling informed decisions to be made when planning water systems for greenfield developments.

40 CFR 141.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... system of a public water system and is intended for distribution and consumption without further... characteristics such as turbidity, temperature, conductivity, or pH which closely correlate to climatological or... containing a disinfectant residual after 7 days at a temperature of 25 °C or above. Medium-size water system...

40 CFR 141.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... system of a public water system and is intended for distribution and consumption without further... characteristics such as turbidity, temperature, conductivity, or pH which closely correlate to climatological or... containing a disinfectant residual after 7 days at a temperature of 25 °C or above. Medium-size water system...

40 CFR 141.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... system of a public water system and is intended for distribution and consumption without further... characteristics such as turbidity, temperature, conductivity, or pH which closely correlate to climatological or... containing a disinfectant residual after 7 days at a temperature of 25 °C or above. Medium-size water system...

Solar-Heated and Cooled Office Building--Columbus, Ohio

NASA Technical Reports Server (NTRS)

1982-01-01

Final report documents solar-energy system installed in office building to provide space heating, space cooling and domestic hot water. Collectors mounted on roof track Sun and concentrate rays on fluid-circulating tubes. Collected energy is distributed to hot-water-fired absorption chiller and space-heating and domestic-hot-water preheating systems.

The use of Jatropha curcas to achieve a self sufficient water distribution system: A case study in rural Senegal

NASA Astrophysics Data System (ADS)

Archer, Alexandra

The use of Jatropha curcas as a source of oil for fueling water pumps holds promise for rural communities struggling to achieve water security in arid climates. The potential for use in developing communities as an affordable, sustainable fuel source has been highly recommended for many reasons: it is easily propagated, drought resistant, grows rapidly, and has high-oil-content seeds, as well as medicinal and economic potential. This study uses a rural community in Senegal, West Africa, and calculates at what level of Jatropha curcas production the village is able to be self-sufficient in fueling their water system to meet drinking, sanitation and irrigation requirements. The current water distribution system was modelled to represent irrigation requirements for nine different Jatropha curcas cultivation and processing schemes. It was found that a combination of using recycled greywater for irrigation and a mechanical press to maximize oil recovered from the seeds of mature Jatropha curcas trees, would be able to operate the water system with no diesel required.

Diagnosing Trouble Spots Caused by an Irrigation System

Treesearch

John R. Scholtes

2002-01-01

I discuss a testing procedure to determine the water distribution pattern of a sprinkler irrigation system and steps that may be taken to improve uniformity of application. All irrigation systems require testing and maintenance to assure that water application is as uniform as possible. Even new systems installed to a manufacturer's specifications should be "...

Evaluation of a spatially-distributed Thornthwaite water-balance model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lough, J.A.

1993-03-01

A small watershed of low relief in coastal New Hampshire was divided into hydrologic sub-areas in a geographic information system on the basis of soils, sub-basins and remotely-sensed landcover. Three variables were spatially modeled for input to 49 individual water-balances: available water content of the root zone, water input and potential evapotranspiration (PET). The individual balances were weight-summed to generate the aggregate watershed-balance, which saw 9% (48--50 mm) less annual actual-evapotranspiration (AET) compared to a lumped approach. Analysis of streamflow coefficients suggests that the spatially-distributed approach is more representative of the basin dynamics. Variation of PET by landcover accounted formore » the majority of the 9% AET reduction. Variation of soils played a near-negligible role. As a consequence of the above points, estimates of landcover proportions and annual PET by landcover are sufficient to correct a lumped water-balance in the Northeast. If remote sensing is used to estimate the landcover area, a sensor with a high spatial resolution is required. Finally, while the lower Thornthwaite model has conceptual limitations for distributed application, the upper Thornthwaite model is highly adaptable to distributed problems and may prove useful in many earth-system models.« less

Perceptional and socio-demographic factors associated with household drinking water management strategies in rural Puerto Rico.

PubMed

Jain, Meha; Lim, Yili; Arce-Nazario, Javier A; Uriarte, María

2014-01-01

Identifying which factors influence household water management can help policy makers target interventions to improve drinking water quality for communities that may not receive adequate water quality at the tap. We assessed which perceptional and socio-demographic factors are associated with household drinking water management strategies in rural Puerto Rico. Specifically, we examined which factors were associated with household decisions to boil or filter tap water before drinking, or to obtain drinking water from multiple sources. We find that households differ in their management strategies depending on the institution that distributes water (i.e. government PRASA vs community-managed non-PRASA), perceptions of institutional efficacy, and perceptions of water quality. Specifically, households in PRASA communities are more likely to boil and filter their tap water due to perceptions of low water quality. Households in non-PRASA communities are more likely to procure water from multiple sources due to perceptions of institutional inefficacy. Based on informal discussions with community members, we suggest that water quality may be improved if PRASA systems improve the taste and odor of tap water, possibly by allowing for dechlorination prior to distribution, and if non-PRASA systems reduce the turbidity of water at the tap, possibly by increasing the degree of chlorination and filtering prior to distribution. Future studies should examine objective water quality standards to identify whether current management strategies are effective at improving water quality prior to consumption.

Perceptional and Socio-Demographic Factors Associated with Household Drinking Water Management Strategies in Rural Puerto Rico

PubMed Central

Jain, Meha; Lim, Yili; Arce-Nazario, Javier A.; Uriarte, María

2014-01-01

Identifying which factors influence household water management can help policy makers target interventions to improve drinking water quality for communities that may not receive adequate water quality at the tap. We assessed which perceptional and socio-demographic factors are associated with household drinking water management strategies in rural Puerto Rico. Specifically, we examined which factors were associated with household decisions to boil or filter tap water before drinking, or to obtain drinking water from multiple sources. We find that households differ in their management strategies depending on the institution that distributes water (i.e. government PRASA vs community-managed non-PRASA), perceptions of institutional efficacy, and perceptions of water quality. Specifically, households in PRASA communities are more likely to boil and filter their tap water due to perceptions of low water quality. Households in non-PRASA communities are more likely to procure water from multiple sources due to perceptions of institutional inefficacy. Based on informal discussions with community members, we suggest that water quality may be improved if PRASA systems improve the taste and odor of tap water, possibly by allowing for dechlorination prior to distribution, and if non-PRASA systems reduce the turbidity of water at the tap, possibly by increasing the degree of chlorination and filtering prior to distribution. Future studies should examine objective water quality standards to identify whether current management strategies are effective at improving water quality prior to consumption. PMID:24586302

EFFECT OF BACTERIAL SULFATE REDUCTION ON IRON-CORROSION SCALES

EPA Science Inventory

Iron-sulfur geochemistry is important in many natural and engineered environments including drinking water systems. In the anaerobic environment beneath scales of corroding iron drinking water distribution system pipes, sulfate reducing bacteria (SRB) produce sulfide from natura...

Optimal Water-Power Flow Problem: Formulation and Distributed Optimal Solution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dall-Anese, Emiliano; Zhao, Changhong; Zamzam, Admed S.

This paper formalizes an optimal water-power flow (OWPF) problem to optimize the use of controllable assets across power and water systems while accounting for the couplings between the two infrastructures. Tanks and pumps are optimally managed to satisfy water demand while improving power grid operations; {for the power network, an AC optimal power flow formulation is augmented to accommodate the controllability of water pumps.} Unfortunately, the physics governing the operation of the two infrastructures and coupling constraints lead to a nonconvex (and, in fact, NP-hard) problem; however, after reformulating OWPF as a nonconvex, quadratically-constrained quadratic problem, a feasible point pursuit-successivemore » convex approximation approach is used to identify feasible and optimal solutions. In addition, a distributed solver based on the alternating direction method of multipliers enables water and power operators to pursue individual objectives while respecting the couplings between the two networks. The merits of the proposed approach are demonstrated for the case of a distribution feeder coupled with a municipal water distribution network.« less

Microbial Community Profile of a Lead Service Line Removed from a Drinking Water Distribution System▿

PubMed Central

White, Colin; Tancos, Matthew; Lytle, Darren A.

2011-01-01

A corroded lead service line was removed from a drinking water distribution system, and the microbial community was profiled using 16S rRNA gene techniques. This is the first report of the characterization of a biofilm on the surface of a corroded lead drinking water service line. The majority of phylotypes have been linked to heavy-metal-contaminated environments. PMID:21652741

Radionuclide transport in the "sediments - water - plants" system of the water bodies at the Semipalatinsk test site.

PubMed

Aidarkhanova, A K; Lukashenko, S N; Larionova, N V; Polevik, V V

2018-04-01

This paper provides research data on levels and character of radionuclide contamination distribution in the «sediments- water - plants » system of objects of the Semipalatinsk test site (STS). As the research objects there were chosen water bodies of man-made origin which located at the territory of "Experimental Field", "Balapan", "Telkem" and "Sary-Uzen" testing sites. For research the sampling of bottom sediments, water, lakeside and water plants was taken. Collected samples were used to determine concentration of anthropogenic radionuclides 90 Sr, 239+240 Pu, 241 Am, 137 Cs. The distribution coefficient (K d ) was calculated as the ratio of the content of radionuclides in the sediments to the content in water, and the concentration ratio (F V ) was calculated as the ratio of radionuclide content in plants to the content in sediments or soil. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characterization of biofilm and corrosion of cast iron pipes in drinking water distribution system with UV/Cl2 disinfection.

PubMed

Zhu, Ying; Wang, Haibo; Li, Xiaoxiao; Hu, Chun; Yang, Min; Qu, Jiuhui

2014-09-01

The effect of UV/Cl2 disinfection on the biofilm and corrosion of cast iron pipes in drinking water distribution system were studied using annular reactors (ARs). Passivation occurred more rapidly in the AR with UV/Cl2 than in the one with Cl2 alone, decreasing iron release for higher corrosivity of water. Based on functional gene, pyrosequencing assays and principal component analysis, UV disinfection not only reduced the required initial chlorine dose, but also enhanced denitrifying functional bacteria advantage in the biofilm of corrosion scales. The nitrate-reducing bacteria (NRB) Dechloromonas exhibited the greatest corrosion inhibition by inducing the redox cycling of iron to enhance the precipitation of iron oxides and formation of Fe3O4 in the AR with UV/Cl2, while the rhizobia Bradyrhizobium and Rhizobium, and the NRB Sphingomonas, Brucella producing siderophores had weaker corrosion-inhibition effect by capturing iron in the AR with Cl2. These results indicated that the microbial redox cycling of iron was possibly responsible for higher corrosion inhibition and lower effect of water Larson-Skold Index (LI) changes on corrosion. This finding could be applied toward the control of water quality in drinking water distribution systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Waterborne outbreaks in Norway 2003-2012].

PubMed

Guzman-Herrador, Bernardo; de Blasio, Birgitte Freiesleben; Lund, Vidar; MacDonald, Emily; Vold, Line; Wahl, Erik; Nygård, Karin

2016-04-19

We describe the status of waterborne outbreaks notified in Norway and discuss this in the context of outbreaks recorded in previous years, to gain a better understanding of their development in Norway in recent years. We have collected information on all outbreaks notified to the Norwegian Institute of Public Health via the surveillance system for communicable diseases in the ten-year period from 2003-2012 for which drinking water was given as the suspected cause. Altogether 28 waterborne outbreaks with a total of 8,060 persons reported as ill were notified in the period. The majority of outbreaks resulted in fewer than 100 cases of illness. There were two outbreaks with more than 1,000 cases of illness: an oubreak of campylobacteriosis in Røros and an oubreak of giardiasis in Bergen. In more than half of the outbreaks, water was supplied from public water distribution systems (16/28 outbreaks, 57%). In addition, a large proportion was linked to individual households with their own water supply (12/28 outbreaks, 43%). Most of the outbreaks in the ten-year period were linked to public water distribution systems, while almost half were linked to non-disinfected water supplies to individual households. Although most of the outbreaks were small, two extensive outbreaks were also registered in the period, resulting in more than one thousand cases of illness. This underscores the need for good contingency planning and surveillance, so that suspicion of waterborne outbreaks is rapidly notified to the responsible authorities, and the importance of good protection of water sources, as well as proper maintenance of water treatment plants and distribution systems.

The Challenge of Providing Safe Water with an Intermittently Supplied Piped Water Distribution System

NASA Astrophysics Data System (ADS)

Kumpel, E.; Nelson, K. L.

2012-12-01

An increasing number of urban residents in low- and middle-income countries have access to piped water; however, this water is often not available continuously. 84% of reporting utilities in low-income countries provide piped water for fewer than 24 hours per day (van den Berg and Danilenko, 2010), while no major city in India has continuous piped water supply. Intermittent water supply leaves pipes vulnerable to contamination and forces households to store water or rely on alternative unsafe sources, posing a health threat to consumers. In these systems, pipes are empty for long periods of time and experience low or negative pressure even when water is being supplied, leaving them susceptible to intrusion from sewage, soil, or groundwater. Households with a non-continuous supply must collect and store water, presenting more opportunities for recontamination. Upgrading to a continuous water supply, while an obvious solution to these challenges, is currently out of reach for many resource-constrained utilities. Despite its widespread prevalence, there are few data on the mechanisms causing contamination in an intermittent supply and the frequency with which it occurs. Understanding the impact of intermittent operation on water quality can lead to strategies to improve access to safe piped water for the millions of people currently served by these systems. We collected over 100 hours of continuous measurements of pressure and physico-chemical water quality indicators and tested over 1,000 grab samples for indicator bacteria over 14 months throughout the distribution system in Hubli-Dharwad, India. This data set is used to explore and explain the mechanisms influencing water quality when piped water is provided for a few hours every 3-5 days. These data indicate that contamination occurs along the distribution system as water travels from the treatment plant to reservoirs and through intermittently supplied pipes to household storage containers, while real-time measurements document variability in water quality throughout the 2-8 hour supply period. Our results show that piped water is not always safe water, but that safe water can be achieved in an intermittent supply under certain physical and operational conditions. Intermittent piped water supply is an important constraint on access to safe water in towns and cities in low-income countries, and strategies that improve these existing systems can help urban residents gain access to safe water. References van den Berg, C., and Danilenko, A. (2010). "The IBNET Water Supply and Sanitation Performance Blue Book: The International Benchmarking Network for Water and Sanitation Utilities Databook." World Bank Washington, DC.

Low Concentration of Salmonella enterica and Generic Escherichia coli in Farm Ponds and Irrigation Distribution Systems Used for Mixed Produce Production in Southern Georgia.

PubMed

Antaki, Elizabeth M; Vellidis, George; Harris, Casey; Aminabadi, Peiman; Levy, Karen; Jay-Russell, Michele T

2016-10-01

Studies have shown that irrigation water can be a vector for pathogenic bacteria. Due to this, the Food Safety Modernization Act's (FSMA) produce safety rule requires that agricultural water directly applied to produce be safe and of adequate sanitary quality for use, which may pose a challenge for some farmers. The purpose of this research was to assess the presence and concentration of Salmonella and generic Escherichia coli in irrigation water from distribution systems in a mixed produce production region of southern Georgia. Water samples were collected during three growing seasons at three farms irrigating crops with surface water (Pond 1, Pond 2) or groundwater (Well) during 2012-2013. Salmonella and generic E. coli populations were monitored by culture and Most Probable Number (MPN). Confirmed isolates were characterized by pulsed-field gel electrophoresis and serotyping. In Pond 1, Salmonella was detected in 2/21 surface, 5/26 subsurface, 10/50 center pivot, and 0/16 solid set sprinkler head water samples. In Pond 2, Salmonella was detected in 2/18 surface, 1/18 subsurface, 6/36 drip line start, and 8/36 drip line end water samples. Twenty-six well pumps and 64 associated drip line water samples were negative. The overall mean Salmonella concentration for positive water samples was 0.03 MPN/100 mL (range <0.0011-1.8 MPN/100 mL). Nine Salmonella serovars comprising 22 pulsotypes were identified. Identical serovars and subtypes were found three times on the same day and location: Pond 1-Pivot-Cantaloupe (serovar Rubislaw), Pond 1-Pivot-Peanut (serovar Saintpaul), and Pond 2-Drip Line Start-Drip Line End-Yellow Squash (serovar III_16z10:e,n,x,z15). Generic E. coli was detected in water from both farm ponds and irrigation distribution systems, but the concentrations met FSMA microbial water quality criteria. The results from this study will allow producers in southern Georgia to better understand how potential pathogens move through irrigation distribution systems.

Epidemiology of urban water distribution systems

NASA Astrophysics Data System (ADS)

Bardet, Jean-Pierre; Little, Richard

2014-08-01

Urban water distribution systems worldwide contain numerous old and fragile pipes that inevitably break, flood streets and damage property, and disrupt economic and social activities. Such breaks often present dramatically in temporal clusters as occurred in Los Angeles during 2009. These clustered pipe breaks share many characteristics with human mortality observed during extreme climatological events such as heat waves or air pollution. Drawing from research and empirical studies in human epidemiology, a framework is introduced to analyze the time variations of disruptive pipe breaks that can help water agencies better understand clustered pipe failures and institute measures to minimize the disruptions caused by them. It is posited that at any time, a cohort of the pipes comprising the water distribution system will be in a weakened state due to fatigue and corrosion. This frail cohort becomes vulnerable during normal operations and ultimately breaks due to rapid increase in crack lengths induced by abnormal stressors. The epidemiological harvesting model developed in this paper simulates an observed time series of monthly pipe breaks and has both explanatory and predictive power. It also demonstrates that models from nonengineering disciplines such as medicine can provide improved insights into the performance of infrastructure systems.

Surveillance for waterborne disease and outbreaks associated with drinking water and water not intended for drinking--United States, 2003-2004.

PubMed

Liang, Jennifer L; Dziuban, Eric J; Craun, Gunther F; Hill, Vincent; Moore, Matthew R; Gelting, Richard J; Calderon, Rebecca L; Beach, Michael J; Roy, Sharon L

2006-12-22

Since 1971, CDC, the U.S. Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists have maintained a collaborative Waterborne Disease and Outbreaks Surveillance System for collecting and reporting data related to occurrences and causes of waterborne disease and outbreaks (WBDOs). This surveillance system is the primary source of data concerning the scope and effects of WBDOs in the United States. Data presented summarize 36 WBDOs that occurred during January 2003-December 2004 and nine previously unreported WBDOs that occurred during 1982-2002. The surveillance system includes data on WBDOs associated with drinking water, water not intended for drinking (excluding recreational water), and water of unknown intent. Public health departments in the states, territories, localities, and Freely Associated States (i.e., the Republic of the Marshall Islands, the Federated States of Micronesia, and the Republic of Palau, formerly parts of the U.S.-administered Trust Territory of the Pacific Islands) are primarily responsible for detecting and investigating WBDOs and voluntarily reporting them to CDC by using a standard form. During 2003-2004, a total of 36 WBDOs were reported by 19 states; 30 were associated with drinking water, three were associated with water not intended for drinking, and three were associated with water of unknown intent. The 30 drinking water-associated WBDOs caused illness among an estimated 2,760 persons and were linked to four deaths. Etiologic agents were identified in 25 (83.3%) of these WBDOs: 17 (68.0%) involved pathogens (i.e., 13 bacterial, one parasitic, one viral, one mixed bacterial/parasitic, and one mixed bacterial/parasitic/viral), and eight (32.0%) involved chemical/toxin poisonings. Gastroenteritis represented 67.7% of the illness related to drinking water-associated WBDOs; acute respiratory illness represented 25.8%, and dermatitis represented 6.5%. The classification of deficiencies contributing to WBDOs has been revised to reflect the categories of concerns associated with contamination at or in the source water, treatment facility, or distribution system (SWTD) that are under the jurisdiction of water utilities, versus those at points not under the jurisdiction of a water utility or at the point of water use (NWU/POU), which includes commercially bottled water. A total of 33 deficiencies were cited in the 30 WBDOs associated with drinking water: 17 (51.5%) NWU/POU, 14 (42.4%) SWTD, and two (6.1%) unknown. The most frequently cited NWU/POU deficiencies involved Legionella spp. in the drinking water system (n = eight [47.1%]). The most frequently cited SWTD deficiencies were associated with distribution system contamination (n = six [42.9%]). Contaminated ground water was a contributing factor in seven times as many WBDOs (n = seven) as contaminated surface water (n = one). Approximately half (51.5%) of the drinking water deficiencies occurred outside the jurisdiction of a water utility in situations not currently regulated by EPA. The majority of the WBDOs in which deficiencies were not regulated by EPA were associated with Legionella spp. or chemicals/toxins. Problems in the distribution system were the most commonly identified deficiencies under the jurisdiction of a water utility, underscoring the importance of preventing contamination after water treatment. The substantial proportion of WBDOs involving contaminated ground water provides support for the Ground Water Rule (finalized in October 2006), which specifies when corrective action is required for public ground water systems. CDC and EPA use surveillance data to identify the types of water systems, deficiencies, and etiologic agents associated with WBDOs and to evaluate the adequacy of current technologies and practices for providing safe drinking water. Surveillance data also are used to establish research priorities, which can lead to improved water-quality regulation development. The growing proportion of drinking water deficiencies that are not addressed by current EPA rules emphasizes the need to address risk factors for water contamination in the distribution system and at points not under the jurisdiction of water utilities.

Improved biostability assessment of drinking water with a suite of test methods at a water supply treating eutrophic lake water.

PubMed

van der Kooij, Dick; Martijn, Bram; Schaap, Peter G; Hoogenboezem, Wim; Veenendaal, Harm R; van der Wielen, Paul W J J

2015-12-15

Assessment of drinking-water biostability is generally based on measuring bacterial growth in short-term batch tests. However, microbial growth in the distribution system is affected by multiple interactions between water, biofilms and sediments. Therefore a diversity of test methods was applied to characterize the biostability of drinking water distributed without disinfectant residual at a surface-water supply. This drinking water complied with the standards for the heterotrophic plate count and coliforms, but aeromonads periodically exceeded the regulatory limit (1000 CFU 100 mL(-1)). Compounds promoting growth of the biopolymer-utilizing Flavobacterium johnsoniae strain A3 accounted for c. 21% of the easily assimilable organic carbon (AOC) concentration (17 ± 2 μg C L(-1)) determined by growth of pure cultures in the water after granular activated-carbon filtration (GACF). Growth of the indigenous bacteria measured as adenosine tri-phosphate in water samples incubated at 25 °C confirmed the low AOC in the GACF but revealed the presence of compounds promoting growth after more than one week of incubation. Furthermore, the concentration of particulate organic carbon in the GACF (83 ± 42 μg C L(-1), including 65% carbohydrates) exceeded the AOC concentration. The increased biomass accumulation rate in the continuous biofouling monitor (CBM) at the distribution system reservoir demonstrated the presence of easily biodegradable by-products related to ClO2 dosage to the GACF and in the CBM at 42 km from the treatment plant an iron-associated biomass accumulation was observed. The various methods applied thus distinguished between easily assimilable compounds, biopolymers, slowly biodegradable compounds and biomass-accumulation potential, providing an improved assessment of the biostability of the water. Regrowth of aeromonads may be related to biomass-turnover processes in the distribution system, but establishment of quantitative relationships is needed for confirmation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Water and Carbon Footprints for Sustainability Analysis of Urban Infrastructure

EPA Science Inventory

Water and transportation infrastructures define spatial distribution of urban population and economic activities. In this context, energy and water consumed per capita are tangible measures of how efficient water and transportation systems are constructed and operated. At a hig...

Nitrification in Water and Wastewater Treatment

EPA Science Inventory

This chapter discusses available information on the occurrence of nitrification in water treatment plants and its potential impact on distribution system water quality. Nitrification as part of the water treatment process can occur whenever ammonia is present in or added to the s...

EPANET USERS MANUAL

EPA Science Inventory

EPANET is a computer program that performs extended period simulation of hydraulic and water quality behavior within drinking water distribution systems. It tracks the flow of water in each pipe, the pressure at each pipe junction, the height of water in each storage tank, and th...

Surveillance for waterborne disease outbreaks associated with drinking water---United States, 2007--2008.

PubMed

Brunkard, Joan M; Ailes, Elizabeth; Roberts, Virginia A; Hill, Vincent; Hilborn, Elizabeth D; Craun, Gunther F; Rajasingham, Anu; Kahler, Amy; Garrison, Laurel; Hicks, Lauri; Carpenter, Joe; Wade, Timothy J; Beach, Michael J; Yoder Msw, Jonathan S

2011-09-23

Since 1971, CDC, the Environmental Protection Agency (EPA), and the Council of State and Territorial Epidemiologists have collaborated on the Waterborne Disease and Outbreak Surveillance System (WBDOSS) for collecting and reporting data related to occurrences and causes of waterborne disease outbreaks associated with drinking water. This surveillance system is the primary source of data concerning the scope and health effects of waterborne disease outbreaks in the United States. Data presented summarize 48 outbreaks that occurred during January 2007--December 2008 and 70 previously unreported outbreaks. WBDOSS includes data on outbreaks associated with drinking water, recreational water, water not intended for drinking (WNID) (excluding recreational water), and water use of unknown intent (WUI). Public health agencies in the states, U.S. territories, localities, and Freely Associated States are primarily responsible for detecting and investigating outbreaks and reporting them voluntarily to CDC by a standard form. Only data on outbreaks associated with drinking water, WNID (excluding recreational water), and WUI are summarized in this report. Outbreaks associated with recreational water are reported separately. A total of 24 states and Puerto Rico reported 48 outbreaks that occurred during 2007--2008. Of these 48 outbreaks, 36 were associated with drinking water, eight with WNID, and four with WUI. The 36 drinking water--associated outbreaks caused illness among at least 4,128 persons and were linked to three deaths. Etiologic agents were identified in 32 (88.9%) of the 36 drinking water--associated outbreaks; 21 (58.3%) outbreaks were associated with bacteria, five (13.9%) with viruses, three (8.3%) with parasites, one (2.8%) with a chemical, one (2.8%) with both bacteria and viruses, and one (2.8%) with both bacteria and parasites. Four outbreaks (11.1%) had unidentified etiologies. Of the 36 drinking water--associated outbreaks, 22 (61.1%) were outbreaks of acute gastrointestinal illness (AGI), 12 (33.3%) were outbreaks of acute respiratory illness (ARI), one (2.8%) was an outbreak associated with skin irritation, and one (2.8%) was an outbreak of hepatitis. All outbreaks of ARI were caused by Legionella spp. A total of 37 deficiencies were identified in the 36 outbreaks associated with drinking water. Of the 37 deficiencies, 22 (59.5%) involved contamination at or in the source water, treatment facility, or distribution system; 13 (35.1%) occurred at points not under the jurisdiction of a water utility; and two (5.4%) had unknown/insufficient deficiency information. Among the 21 outbreaks associated with source water, treatment, or distribution system deficiencies, 13 (61.9%) were associated with untreated ground water, six (28.6%) with treatment deficiencies, one (4.8%) with a distribution system deficiency, and one (4.8%) with both a treatment and a distribution system deficiency. No outbreaks were associated with untreated surface water. Of the 21 outbreaks, 16 (76.2%) occurred in public water systems (drinking water systems under the jurisdiction of EPA regulations and water utility management), and five (23.8%) outbreaks occurred in individual systems (all of which were associated with untreated ground water). Among the 13 outbreaks with deficiencies not under the jurisdiction of a water system, 12 (92.3%) were associated with the growth of Legionella spp. in the drinking water system, and one (7.7%) was associated with a plumbing deficiency. In the two outbreaks with unknown deficiencies, one was associated with a public water supply, and the other was associated with commercially bottled water. The 70 previously unreported outbreaks included 69 Legionella outbreaks during 1973--2000 that were not reportable previously to WBDOSS and one previously unreported outbreak from 2002. More than half of the drinking water--associated outbreaks reported during the 2007--2008 surveillance period were associated with untreated or inadequately treated ground water, indicating that contamination of ground water remains a public health problem. The majority of these outbreaks occurred in public water systems that are subject to EPA's new Ground Water Rule (GWR), which requires the majority of community water systems to complete initial sanitary surveys by 2012. The GWR focuses on identification of deficiencies, protection of wells and springs from contamination, and providing disinfection when necessary to protect against bacterial and viral agents. In addition, several drinking water--associated outbreaks that were related to contaminated ground water appeared to occur in systems that were potentially under the influence of surface water. Future efforts to collect data systematically on contributing factors associated with drinking water outbreaks and deficiencies, including identification of ground water under the direct influence of surface water and the criteria used for their classification, would be useful to better assess risks associated with ground water. During 2007--2008, Legionella was the most frequently reported etiology among drinking water--associated outbreaks, following the pattern observed since it was first included in WBDOSS in 2001. However, six (50%) of the 12 drinking water--associated Legionella outbreaks were reported from one state, highlighting the substantial variance in outbreak detection and reporting across states and territories. The addition of published and CDC-investigated legionellosis outbreaks to the WBDOSS database clarifies that Legionella is not a new public health issue. During 2009, Legionella was added to EPA's Contaminant Candidate List for the first time. CDC and EPA use WBDOSS surveillance data to identify the types of etiologic agents, deficiencies, water systems, and sources associated with waterborne disease outbreaks and to evaluate the adequacy of current technologies and practices for providing safe drinking water. Surveillance data also are used to establish research priorities, which can lead to improved water quality regulation development. Approximately two thirds of the outbreaks associated with untreated ground water reported during the 2007--2008 surveillance period occurred in public water systems. When fully implemented, the GWR that was promulgated in 2006 is expected to result in decreases in ground water outbreaks, similar to the decreases observed in surface water outbreaks after enactment of the Surface Water Treatment Rule in 1974 and its subsequent amendments. One third of drinking water--associated outbreaks occurred in building premise plumbing systems outside the jurisdiction of water utility management and EPA regulations; Legionella spp. accounted for >90% of these outbreaks, indicating that greater attention is needed to reduce the risk for legionellosis in building plumbing systems. Finally, a large communitywide drinking water outbreak occurred in 2008 in a public water system associated with a distribution system deficiency, underscoring the importance of maintaining and upgrading drinking water distribution system infrastructure to provide safe water and protect public health.

Plutonium partitioning in water-granite and water-α-FeOOH systems: from a viewpoint of a three-phase system.

PubMed

Lin, Jianfeng; Dang, Haijun; Xie, Jinchuan; Zhou, Guoqing; Li, Mei; Zhang, Jihong

2015-09-01

Traditional sorption experiments commonly treat the colloidal species of low-solubility contaminants as immobile species when separated by centrifugation or ultrafiltration. This study shows that, from a viewpoint of a three-phase system, the mobile Pu species, especially the colloidal species, play an important role in Pu partitioning in water-granite and water-α-FeOOH systems. A new distribution coefficient term Ks/(d+c) was defined to take the mobile colloidal species into consideration, and it differs to the traditional distribution coefficient Ks/d by orders of magnitude in the water-granite and water-α-FeOOH systems. This term, Ks/(d+c), can quantitatively describe Pu partitioning in the suspension, in particular the fraction of mobile species that dominate Pu migration in the environment. The effects of ionic strength (I) and pH on the Pu partitioning in water-granite and water-α-FeOOH systems are well interpreted with respect to the zeta potential change of granite grains, α-FeOOH colloid particles and polymeric Pu. It is concluded that the presence of the α-FeOOH colloid with a low concentration (<10 mg L(-1)) is favorable for the stability of colloidal Pu and leads to large proportion of mobile Pu, especially colloid-associated Pu, which will migrate much faster than dissolved Pu in groundwater.

Reactive solute transport in an asymmetrical fracture-rock matrix system

NASA Astrophysics Data System (ADS)

Zhou, Renjie; Zhan, Hongbin

2018-02-01

The understanding of reactive solute transport in a single fracture-rock matrix system is the foundation of studying transport behavior in the complex fractured porous media. When transport properties are asymmetrically distributed in the adjacent rock matrixes, reactive solute transport has to be considered as a coupled three-domain problem, which is more complex than the symmetric case with identical transport properties in the adjacent rock matrixes. This study deals with the transport problem in a single fracture-rock matrix system with asymmetrical distribution of transport properties in the rock matrixes. Mathematical models are developed for such a problem under the first-type and the third-type boundary conditions to analyze the spatio-temporal concentration and mass distribution in the fracture and rock matrix with the help of Laplace transform technique and de Hoog numerical inverse Laplace algorithm. The newly acquired solutions are then tested extensively against previous analytical and numerical solutions and are proven to be robust and accurate. Furthermore, a water flushing phase is imposed on the left boundary of system after a certain time. The diffusive mass exchange along the fracture/rock matrixes interfaces and the relative masses stored in each of three domains (fracture, upper rock matrix, and lower rock matrix) after the water flushing provide great insights of transport with asymmetric distribution of transport properties. This study has the following findings: 1) Asymmetric distribution of transport properties imposes greater controls on solute transport in the rock matrixes. However, transport in the fracture is mildly influenced. 2) The mass stored in the fracture responses quickly to water flushing, while the mass stored in the rock matrix is much less sensitive to the water flushing. 3) The diffusive mass exchange during the water flushing phase has similar patterns under symmetric and asymmetric cases. 4) The characteristic distance which refers to the zero diffusion between the fracture and the rock matrix during the water flushing phase is closely associated with dispersive process in the fracture.