Search

A protocol for responding to Legionella pneumophila detections in distribution system samples is presented and justified. The protocol was developed using existing protocols for building water systems, vetted in workshops, and provided to utilities participating in a research project. The protocol provides action levels and actions that utilities can take when L. pneumophila is detected in distribution system samples. Action levels are based on the best available science and expert judgment and are similar to those in protocols for assessing building water system monitoring results. Action levels should be reassessed as additional data and knowledge on the occurrence and growth potential of L. pneumophila in distribution systems become available. All positive detections trigger assessments that focus first on conditions local to the sample location and then extend further into the distribution system. Higher concentration or more frequent detections initiate more assertive responses and communication than lower concentration and frequency detections. The protocol provides a starting point for the development of protocols for purposes such as L. pneumophila operational surveillance or within an outbreak investigation. [ABSTRACT FROM AUTHOR]

Tap water's availability, accessibility, and biological safety do not automatically translate into social acceptance. Most Americans no longer drink water directly from the tap but rely on either filters or bottled water. As demonstrated by fieldwork among New York City water‐filter users, filters have the power to restore tap water's acceptability, making this an interesting site to examine the imagined qualities of water and the technopolitics of filtration. Such an examination allows the ethnographic gaze to attend to both the monumental and mundane operations of infrastructures. Unlike other mediating technologies, water filters have a salient catch‐all quality, one that allows filters in the US to participate in a plurality of hydrosocial situations. They furthermore mediate multiple worries and projects around tap water, and they give a semblance of control to users equipped with diverse understandings of how filters function. [ABSTRACT FROM AUTHOR]

Successfully implementing water safety plans (WSPs) in small, municipal drinking water systems is understudied in affluent jurisdictions where WSPs are not required by regulations. We piloted a computer‐based risk assessment survey in eight municipal water systems in Nova Scotia, Canada to evaluate the benefits and challenges of implementing risk assessment strategies in non‐WSP jurisdictions. Semi‐structured interviews were conducted with water operators and managers to gather feedback on the risk assessment survey and process. Results indicated difficulties quantifying risk despite streamlining the risk identification process, resulting in key informants viewing the risk assessment as strictly diagnostic and unlikely to be integrated into operational practice if not required. We identified a need to shift water system culture from a regulatory‐based to a knowledge‐based mindset for successful risk assessment implementation. Clear lines of communication, increased understanding of risk, and commitment to improvement are critical to shifting water system culture toward a risk‐based water quality management approach. [ABSTRACT FROM AUTHOR]

A SURVEY OF US WATER UTILITIES INDICATES A NEED TO DEVELOP AND IMPROVE CROSS-CONNECTION CONTROL PROGRAMS TO HELP ENSURE PUBLIC HEALTH. [ABSTRACT FROM AUTHOR]

The article focuses on 2017 addendum to fourth edition of the 2011 Guidelines for Drinking-water Quality (GDWQ), issued by the World Health Organization (WHO). It mentions that the updated GDWQ includes new guidelines for perchlorate and barium and removes a 4-chloro-2-methylphenoxyacetic acid (MCPA) guideline for lack of significant risk from drinking water. It states that the 2017 addendum provides information on water safety plans, drinking water microbiology, and radionuclides.

The article discusses the publication of several issues of "Journal-American Water Works Association." Topics mention including the responsibilities of the water providers which include to provide a safe and adequate supply of water, public water works systems located in the U.S. and the introduction of the "Manual of American Water Works (1)" by E. M. Baker.

THE ISSUES IN FLINT WILL BE LONG‐LASTING LOCALLY, BUT THE SITUATION ALSO HAS FAR‐REACHING IMPLICATIONS FOR THE WATER UTILITY INDUSTRY AS A WHOLE. [ABSTRACT FROM AUTHOR]

Deltas like the Netherlands always face flooding risk. After the flood of 1953, flood risk management was geared towards achieving full safety, controlling the probability of flooding with high dikes and a shorter coastline. Yet, this approach became increasingly contested, as flood risk control was (re) linked to other values of water, like nature and landscape preservation and economic activities. This paper reconstructs how the process of policy making and implementation has sought to balance these multiple values over time. It shows that public values did not develop linearly into concrete standards and practices. Processes of re-articulation and political renegotiation of the meaning and importance of water safety took different paths with regard to both the river systems and the coastline. Curves in these paths can be seen as feedback mechanisms that verify the robustness of flood risk management measures and/or respond to changes in the character of the public values involved. [ABSTRACT FROM AUTHOR]

Sachet water is growing in importance as a source of drinking water for many people in Nigeria. In recent years, doubts over the quality of sachet water have grown. Commentators often cite poor distribution and storage practice for contamination of sachets. However, the integrity of the production process has been shown to be a weakness but has not received attention from the regulator or producers because of a lack of proper regulation of the industry. This study implemented the hazards analysis and critical control points ( HACCP) framework in eight sachet water factories in Ibadan, Nigeria. The objective was to test HACCP's viability as a proactive management tool for improving sachet water quality. The findings show that HACCP can be adopted within the sachet water industry. However, the implementation of HACCP requires both technical and behavioural changes within the production process. [ABSTRACT FROM AUTHOR]

A paired catchment methodology was used with more than 3 years of data to test whether forests increase base flow in the dry season, despite reduced annual runoff caused by evapotranspiration (the 'sponge-effect hypothesis'), and whether forests reduce maximum runoff rates and totals during storms. The three study catchments were: a 142.3 ha old secondary forest, a 175.6 ha mosaic of mixed age forest, pasture, and subsistence agriculture, and a 35.9 ha actively grazed pasture subcatchment of the mosaic catchment. The two larger catchments are adjacent, with similar morphology, soils, underlying geology, and rainfall. Annual water balances, peak runoff rates, runoff efficiencies, and dry season recessions show significant differences. Dry season runoff from the forested catchment receded more slowly than from the mosaic and pasture catchments. The runoff rate from the forest catchment was 1-50% greater than that from the similarly sized mosaic catchment at the end of the dry season. This observation supports the sponge-effect hypothesis. The pasture and mosaic catchment median runoff efficiencies were 2.7 and 1.8 times that of the forest catchment, respectively, and increased with total storm rainfall. Peak runoff rates from the pasture and mosaic catchments were 1.7 and 1.4 times those of the forest catchment, respectively. The forest catchment produced 35% less total runoff and smaller peak runoff rates during the flood of record in the Panama Canal Watershed. Flood peak reduction and increased streamflows through dry periods are important benefits relevant to watershed management, payment for ecosystem services, water-quality management, reservoir sedimentation, and fresh water security in the Panama Canal watershed and similar tropical landscapes. [ABSTRACT FROM AUTHOR]

Nutrient enrichment of lakes and reservoirs used for a potable water supply can lead to a broad array of adverse effects ranging from operational problems to potential increases in certain human health- related risks. Human health risks that may be exacerbated by nutrient enrichment stem from increases in disinfection by-products, cyanotoxins, and arsenic. New York state is developing numeric nutrient criteria for the protection of water supply lakes and reservoirs by establishing relationships between nutrients, algal abundance, dissolved organic carbon, and trihalomethanes, and then targeting established regulatory endpoints to set appropriate numeric nutrient criteria thresholds. This approach represents a much-needed bridge between the Safe Drinking Water Act and the Clean Water Act by defining source water protection goals. Findings to date from the investigation of 21 systems indicate that a mean chlorophyll a threshold of 4-6 μg/L would likely be protective of potable water supply lakes and reservoirs. [ABSTRACT FROM AUTHOR]

In the evaluation of potential risk from ingestion of groundwater near an impacted site, numerical simulation of fate and transport processes of chemicals of concern is often required. If there is potential concern about multiple chemicals, numerical simulation of each chemical separately is often needed. In this paper, a semi-analytical solution is presented based on a numerical solution of the transport of a conservative and nonreactive tracer. When multiple chemicals undergoing sorption and first-order degradation need to be modeled, we can avoid performing individual numerical simulations for each chemical by applying the semi-analytical solution. Numerical test runs were conducted to verify the semi-analytical solution; simulation results reveal that the concentrations derived from the semi-analytical solution are identical to those derived from the individual numerical fate and transport model simulations. The semi-analytical solution requires steady-state flow conditions, no continuing contaminant source, and similar initial source concentration distributions. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the spatial and temporal factors related to bacterial pathogen contamination with the use of regression and classification tree analysis in the Oldman River, Alberta. The study shows that Escherichia (E.) coli, Campylobacter spp. and Salmonella spp. presence was related to total rainfall, animal manure units and season. Some of the environmental variables examined seem to influence pathogen prevalence and might be useful to portend water safety and quality to improve watershed management practices.

More than 1 billion people, the vast majority of which live in the developing world, lack basic access to clean water for domestic use. For this reason, finding and promoting effective and sustainable solutions for the provision of reliable clean water in developing nations has become a focus of several public health and international development efforts. Even though several means of providing centrally located sources of clean water in developing communities exist, the severity and widespread nature of the water problem has led most development agencies and sanitation experts to strongly advocate the use of point-of-use treatment systems alongside whatever source of water people regularly use. In doing so, however, development practitioners have been careful to point out that any interventions or infrastructure regarding water safety and human health must also adhere to one of the central principles of international development: to facilitate more democratic and participatory models of decision making and governance. To this end, the research reported here focused on the development of a deliberative risk management framework for involving affected stakeholders in decisions about POU water treatment systems. This research, which was grounded in previous studies of structured decision making, took place in two rural villages in the East African nation of Tanzania. [ABSTRACT FROM AUTHOR]

Two studies of domestic water quality were undertaken in rural Cambodia. The first was a programme of quantitative groundwater quality testing and modelling. The second was a qualitative study of perceptions of groundwater quality. This research aimed to compare and contrast findings of these studies in two communes in rural Cambodia. The quantitative study found that in both communes, there is a high risk of encountering bore water with levels of chemical contamination that are detrimental to human health. The qualitative study found that messages from water users is mixed - 60% of bore water users thought their groundwater was of good quality, but 97% treated their water at the point of use before drinking. Results suggest that villages in rural Cambodia would benefit from a better community understanding of groundwater quality and safe water, and the development of more informed domestic water options. [ABSTRACT FROM AUTHOR]

Effective governance that contributes to the integration of water management and land use planning is essential for successful protection of drinking water sources and, ultimately, provision of safe drinking water. In many jurisdictions, land use planning and watershed management occur on separate tracks. This article examines the prospects for integration of these two critical processes. A multicase study approach is used, focusing on the specific objective of protection of drinking water sources. Experiences in three case study watershed regions in Ontario, Canada (Grand River, Upper Thames, and Lake Simcoe), were analyzed. The goal was to identify the extent to which source water protection components and indicators are expressed in land use and watershed-based planning documents. Similarities and differences among the watershed regions are distinguished through a cross-case analysis. The results suggest that a shifting governance regime for drinking water safety in Ontario is contributing to integration between land use and water management. However, proactive and ongoing efforts are required to ensure that integration occurs and that barriers to integration are addressed. Timely guidelines, incentive-based tools, up-to-date and accurate information, and adequate financial resources are essential. [ABSTRACT FROM AUTHOR]

During the drilling process and transport of crude oil, water mixes with the petroleum. At oil terminals, the water settles to the bottom of storage tanks. This drainage water is contaminated with emulsified oil and water-soluble hydrocarbons and must be treated before it can be released into the environment. In this study, we tested the efficiency of a continuous flow, two-stage bioreactor for treating drainage water from an Israeli oil terminal. The bioreactor removed all of the ammonia, 93% of the sulfide and converted 90% of the total organic carbon (TOC) into carbon dioxide. SYBR Gold staining indicated that reactor 1 contained 1.7 × 108 bacteria and 3.7 × 108 phages per millilitre, and reactor 2 contained 1.3 × 108 bacteria and 1.7 × 109 phages per millilitre. The unexpectedly high mineralization of TOC and high concentration of phage in reactor 2 support the concept of a phage-driven microbial loop in the bioremediation of the drainage water. In general, application of this concept in bioremediation of contaminated water has the potential to increase the efficiency of processes. [ABSTRACT FROM AUTHOR]

Although water resources managers speak of a water crisis in Africa, the management of ground water has to date not featured strongly in national and regional African water agendas. Examination of the physical environment of the continent and, in particular, the water resources in relation to the socioeconomic landscape and regional development challenges makes it clear that widely occurring, albeit largely low-yielding, ground water resources will be crucial in the achievement of water security and development. Ground water is important primarily in domestic water and sanitation services, but also for other local productive needs like community gardens, stock watering, and brick-making, all essential to secure a basic livelihood and thus to alleviate poverty. Despite the importance of small-scale farming in Africa, there is little information on the present and potential role of ground water in agriculture. In contrast to its socioeconomic and ecological importance, ground water has remained a poorly understood and managed resource. Widespread contamination of ground water resources is occurring, and the important environmental services of ground water are neglected. There appear to be critical shortcomings in the organizational framework and the building of institutional capacity for ground water. Addressing this challenge will require a much clearer understanding and articulation of ground water's role and contribution to national and regional development objectives and an integrated management framework, with top-down facilitation of local actions. [ABSTRACT FROM AUTHOR]

An indoor experiment was undertaken to investigate the response of phytochelatins and their relationship to cadmium toxicity in Pistia stratiotes L., a free-floating macrophyte, exposed to low concentrations of cadmium typically found in realistic environments. Cadmium concentrations of 0.01 to 0.08 sM had no toxic effects on the growth of this plant, as indicated by no significant changes in th& fresh weights of leaves and roots and the slight induction of phytochelatins in plant tissues, whereas cadmium concentrations of 0.16 to I jsM were toxic, and cadmium toxicity increased with the increase of cadmium concentrations in solutions, accompanied by the dramatic production of phytochelatins in plant tissues, especially in roots. There was a positive correction between root phytochelatin levels and cadmium toxicity, as measured by the growth inhibition rate of the root fresh weight. The results suggested that phytochelatins in aquatic macrophytes can serve as sensitive biomarkers for heavy metal toxicity in a moderately polluted water environment. [ABSTRACT FROM AUTHOR]

Recent years have seen the arrival of an array of early warning systems for the continuous on-line detection of anomalies relating to water security and quality. Numerous methodologies and criteria have been suggested to determine the efficacy of these methods in real-world scenarios. The authors contend that many of these evaluation techniques are deficient in evaluating all of the factors that would be essential in defining a system for deployment for the protection of key installations such as military bases. They suggest specific criteria as a means of comparing various technologies and propose a new method for determining receiver operating characteristic curves. Similar considerations should come into play in the evaluation of systems for civilian uses. [ABSTRACT FROM AUTHOR]

The fundamental problem for any scheme of water management that tries to maximise welfare across a river system is that of determining the optimal allocation at every point. The problem cannot, in general, be avoided by trading water rights because the price will not account for the effect of extraction at any one point on all other points. This article interprets the problem in terms of the indeterminacy that results from missing information on the value of water at internal junctions between rivers. It is then solved in an optimal control theory framework. [ABSTRACT FROM AUTHOR]

The article focuses on a study that examined the use of Soil and Water Assessment Tool (SWAT), with the Sequential Uncertainty Fitting program (SUFI-2), in testing and validating a hydrologic model of Iran based on various factors including river discharges, dam operations and irrigation practices. The study addressed the country's water balance including blue water flow, green water flow and the green water storage. The results depicted that irrigation practices have significantly affected the water balance of provinces whose people are engaging in irrigation farming. The implication of unstable water resource management on the country's food and water security is also explained.

The article focuses on the need for the water sector in the U.S. to invest in response, recovery, and resiliency in order to balance traditional security and preparedness. The water sector is moving towards the formulation of a secure and resilient infrastructure that provides clean and safe water an integral part of daily life. In fact, the water sector recognized a need to raise awareness and understanding of threats facing process control systems. Thus, the water sector should implement initiatives and integrate them into the operational culture of each utility.

Instream flows may be essential in protecting aquatic species that are threatened or endangered. An economic model of the optimal allocation of water under pure uncertainty is developed, with particular attention paid to the situation when a species characterized by critical depensation is affected by instream flows. We adopt the notion of pure uncertainty that Frank Knight and Daniel Ellsberg intended, which applies when decision makers cannot reduce their uncertainty to a unique probability distribution. Following recent work by Hansen, Sargent, and others, we employ robust control as a way to deal with this problem. [ABSTRACT FROM AUTHOR]

Background: Dental unit waterline contamination has become a concern to clinical dentistry. This concern arises from the fact that bacteria sloughed from established biofilms in dental unit waterlines increase heterotrophic bacteria counts in water exiting these units. Methods: Scanning microscopy and bacterial viability staining were used to examine the sessile and planktonic biofilm present in dental unit waterlines and water samples, respectively. In addition, the limulus amebocyte assay was used to measure the lipopolysaccharide (LPS) levels in water samples. Results: All dental unit waterlines were coated with a well-established biofilm made up of filamentous and bacillus-like microorganisms. Water samples collected from these dental units contained high numbers of individual bacteria and bacterial aggregates. A viability staining technique identified significantly more bacteria in water than could be cultured, and 64% of the total bacterial population stained as nonvital. Since the bacterial load (viable and nonviable) was high, we examined the LPS in dental unit water samples. The mean LPS levels in water collected from high-speed and air/water lines in use were 480 and 1,008 endotoxin units (EU)/ml. This was significantly higher than the mean level of 66 EU/ml found in water samples collected from adjacent clinic sinks. The LPS level at the start of the day (2,560 EU/ml) was reduced by 70% with 1 minute of flushing (800 EU/ml). Flushing times of 5 and 10 minutes were not able to reduce LPS levels to zero. Conclusion: The presence of high heterotrophic bacterial counts, sloughing biofilm, and high LPS levels are discussed in relation to patient risk and periodontal wound healing biology. [ABSTRACT FROM AUTHOR]

The authors address the issue of the U.S. water supply's vulnerability to industrial spills. They explain that the procedures to reduce this vulnerability have yet to be implemented due to the shift in national priorities after the September 11, 2001 terrorist attack and because of the belief that finished water is more vulnerable than raw water resources in the water distribution system. They also offer various steps for implementing a proactive program to protect drinking water supplies.

The article focuses on the strategies in minimizing the risk of exposure from mycobacterium avium complex (MAC) and nontuberculous mycobacteria (NTM) in the water supply. The diseases caused by NTM and MAC are highlighted which include cervical lymphadenitis, blood infections and pulmonary diseases. The different types of disinfectants are emphasized which include chlorine, chloramine and chlorine dioxide.

The article discusses the expansion of the multifaceted approach by water suppliers to promote public health protection in the Indianapolis, Indiana. It highlights the importance of capital planning which enables to provide treatment tools necessary to address health concerns. It highlights the high concentrations of Cryptosporidium in the surface water of the city which have been investigated by the U.S. Environmental Protection Agency (EPA).

The article focuses on a study on the U.S. municipal water systems (MWSs) determining the agents of chemical, biological, and radiological (CBR) attacks in water systems, potential effects and detection and decontamination demands. It mentions radionuclides as dangerous threats to MWSs. It cites the estimated impact at 100 billion dollars for water supplies serving 100,000 people. It notes that the remediation of the facilities would be less than 10% of the estimated cost.

The article offers insights on the effort made by the local authorities in Wichita, Kansas to resolve water contamination. It mentions that the municipality has provided various approaches in solving such contamination which enumerates the grab sample analysis and the on-line chemical monitor. Furthermore, Wichita's local authorities have installed a water monitoring system called the BioSentry which have been effective and eliminated shortcomings and greater level of water security and also mention that the system has played a concrete role in efforts to maximize the quality and security of public waters.

The article reports on U.S. President Donald Trump. It highlights his engagement and integrity of science-based policy from climate science to clean water regulations in the U.S. and worldwide. Also emphasized is the increasing awareness for urgent need of policymaking and communication at disciplinary and social regions.

The article presents the author views over adoption of different executive orders by the U.S. president Donald Trump related to environmental protection. Topics discussed include introduction of the Waters of the United States (WOTUS) rule for navigable water by Trump; illustration of water bodies under protection through the Clean Water Act; and analysis of Trump's approaches in water safety along with the U.S. Environmental Protection Agency (EVA) sustenance.

This section offers news briefs concerning the National Ground Water Association (NGWA) as of May 2017. Topics discussed include the NGWA Groundwater Modeling Advisory Panel (GMAP) issuing practical guidance on groundwater modeling, the NGWA Press publishing the book "Operational Stage of the Well" and the association releasing the information brief "Groundwater and Drinking Water," which aims to educate the public about regulations for water systems and water supply safety.

The cover page of the June 2014 issue of the "Clean: Soil, Air, Water" is presented.

The article offers tips on dealing with chemical spills in drinking water supplies as provided by the American Water Works Association (AWWA). Topics discussed include AWWA's suggestion to establish a set of requirements for chemical tanks that may pose risks to public water supplies (PWS), regulations that should be implemented concerning covered chemical tanks according to AWWA and responsibilities of the U.S. Environmental Protection Agency (USEPA) in protecting water supplies from spills.

The article reports on the Whitewater Security's completion of the first phase of a comprehensive three-phase program to safeguard the drinking water of Tel Aviv, Israel. Whitewater Security is a subsidiary of the Whitewater Technology Group. The article describes the company's groundbreaking approach to water security which combines an individually tailored security plan with cutting-edge tools and expert training that enables water authorities to take immediate full control, online in real time, of every aspect of their water supply systems including the pinpoint monitoring of specific locations within cities.

The article focuses on the concerns over the security of water utilities in the U.S. The water community is forced to deal with the water security challenges given incidents that pose security threats. In this connection, the American Water Works Association (AWWA) has addressed the safety and security of the water supply and public health. In fact, the association has partnered with the U.S. Environmental Protection Agency, the Water Environment Federation, and the American Society of Civil Engineers in developing the Water Infrastructure Security enhancement program (WISE).

The article presents the author's views on the topics related to source of water discussed within the issue. The author relates the significance of prevention to overall health and the topics which the publication covers. Topics include the integration of triple-bottom-line philosophy and sustainability, the prevention of cyanotoxins through technology and the implementation of sustainable water management schemes.