bluuebunny/crossref_metadata_2025_split huggingface dataset:
Small system maintenance management using GIS
Authors: Kaufman Martin M. , Wurtz Matthew 
Published: February 2018

It took only three months and less than $3,000 to develop this comprehensive maintenance management system.A geographic information system (GIS) was developed for maintenance operations at a small (6,104 customers) utility district. Characteristics unique to GIS applications, such as the accurate modeling of physical and environmental processes, data modeling and preparation, and the spatial nature of the data, were incorporated into the steps used to develop the system. The steps were problem identification, process modeling, data modeling, developing a data plan, cartographic modeling, data entry, and testing. These steps achieved computability—the transition from a real‐world problem to a computer application. The results give an accurate depiction of the water supply processes, including the hydraulic characteristics of the infrastructure and the service requirements. This low‐cost application was implemented rapidly and has the flexibility to create additional applications.
Waterborne outbreaks of cryptosporidiosis
Authors: Craun Gunther F. , Hubbs Stephen A. , Frost Floyd , Calderon Rebecca L. , Via Steve H. 
Published: February 2018

A review of 35 outbreaks of cryptosporidiosis points to recommendations for prevention of waterborne outbreaks and uncovers a need for more adequate epidemiological data.Cryptosporidium parvum infection occurs worldwide in urban and rural populations, and waterborne outbreaks have been associated with consumption of contaminated drinking water and water during recreational activities. This article reviews the epidemiology and causes of waterborne outbreaks that have been reported in North America and the United Kingdom. Outbreaks were associated with filtered and unfiltered surface water sources, groundwater sources, and contamination of the distribution system. In most outbreaks, sources of contamination and deficiencies in treatment and operation were identified. Available epidemiological information is inadequate to estimate endemic waterborne risks, and analytical studies should be conducted to assess these risks. A major issue to consider in assessing waterborne cryptosporidiosis risks is the role of protective immunity, which may be acquired through low‐level sporadic exposures to C. parvum in drinking water.
Cost of advanced UV for inactivating crypto
Authors: Dyksen John E. , Marshall Marilyn M. , Gera Arun , Clancy Jennifer L. 
Published: February 2018

Cost comparisons indicate that advanced UV technology may be cost‐effective for drinking water treatment and competitive with other treatment alternatives.A collaborative project funded by the AWWA Research Foundation and the Electric Power Research Institute evaluated five electrotechnologies for their ability to inactivate viable Cryptosporidium oocysts. Advanced ultraviolet (UV) light technology was found to provide greater than 4‐log inactivation of Cryptosporidium. This UV technology was evaluated further from an engineering design and economic standpoint to determine the feasibility of implementing it at existing treatment facilities. This article describes the results of the engineering and economic analyses for advanced UV electrotechnology.
Controlling Legionella using copper‐silver ionization
Authors: States Stanley , Kuchta John , Young William , Conley Louis , Ge John , Costello Michael , Dowling John , Wadowsky Robert 
Published: February 2018

Nursing homes as well as hospitals are at risk for Legionella contamination.Hospital‐acquired Legionnaires' disease, associated with contaminated hot water plumbing systems, is a well‐documented problem in hospitals and may also be a problem in nursing homes. In this study, four nursing homes were surveyed to determine the extent to which potable hot water systems were colonized by Legionella pneumophila and to measure microbial and chemical factors related to legionellae contamination. The survey indicated that two of the homes were heavily contaminated with Legionella and suggested that contamination is associated with hot water temperatures, chlorine concentrations, the presence of free‐living amoebae, and possibly intermittent seeding of building plumbing systems with legionellae from the public water supply. The most heavily colonized nursing home plumbing system was then equipped with a copper‐silver ionization device, designed to control Legionella. A subsequent two‐year evaluation indicated that the device controlled Legionella but not amoebae or non‐Legionellaceae bacteria. Maintenance of the ionization system and monitoring of legionellae and metals concentrations in the water are important for effective use of the control device.
Sulfide‐oxidizing bacteria: their role during air‐stripping
Authors: Dell'Orco Michael J. , Chadik Paul A. , Bitton Gabriel , Neumann R.P. 
Published: February 2018

Biological oxidation of sulfide enhances the removal of sulfide from groundwater by diffused aeration.Air‐stripping, used to remove hydrogen sulfide naturally present in many groundwater supplies, commonly causes sulfideoxidizing bacteria to proliferate. The role of sulfide‐oxidizing bacteria during air‐stripping was investigated in a diffused‐air pilot reactor modeled after an existing treatment facility. Visible bacterial filaments and biofilm developed within a few days and increased both the sulfide removed from and turbidity in the effluent. Total sulfide, dissolved oxygen, pH, and electrode potential were monitored at eight locations in the reactor to characterize the process.
Tokyo's modern water system celebrates its centennial
Authors: Kawakita Kazunori 
Published: February 2018

The city's Bureau of Waterworks has made strides in purifying and conserving water, meeting demand, upgrading pipelines, and preparing for earthquakes.In 1898, Tokyo, Japan, modernized its then 300‐year‐old water supply system by building a slow sand filtration plant. The modernized system has come a long way and is celebrating its one hundredth anniversary in 1998. This article highlights the triumphs and tribulations Tokyo has faced over the years in delivering drinking water to its citizens. It covers the development of the dams, reservoirs, and rivers used to secure water; Tokyo's Bureau of Waterworks; efforts to conserve water; upgrades to the distribution system; and emergency preparations for responding to earthquakes.
Using PAC–UF to treat a low‐quality surface water
Authors: Jack Anne M. , Clark Mark M. 
Published: February 2018

In a pilot study, a PAC‐UF process shows promise in treating a low‐quality source water without sacrificing either cost or operating efficiency.A water supply from a Midwestern agricultural watershed was treated using a hybrid powdered activated carbon‐ultrafiltration (PAC‐UF) pilot system. The pilot was operated remotely over a four‐month period using five combinations of target flux and backwashing frequency. Simple statistical techniques were used to analyze energy and cost efficiency for each combination. Energy use was minimized when target flux and the period between backwashes were minimized. Total cost was minimized when the target flux and period between backwashes were maximized. A degradation in water quality at the end of the pilot‐testing period presented a significant operational challenge that was overcome through the direct addition of 14 mg/L ferric chloride to the UF recirculation loop. The sudden degradation in water quality is testimony to the need for pilot tests designed to evaluate the effects of seasonal water quality variations.
Tracking filter performance with particle counting
Authors: Hargesheimer Erika E. , McTigue Nancy E. , Mielke J. Laurie , Yee Phillip , Elford Tom 
Published: February 2018

Particle counting can be a sensitive tool for monitoring filter performance and improving the quality of finished water.Minor changes (1–2 mg/L) in the primary coagulant dosage can significantly affect particle counts in filtered water. Jar tests were inconclusive in selecting a coagulant dosage for source water of low turbidity (<5 ntu). Measurements of turbidity in filtered water were also not definitively altered by small changes in coagulant dosage. On‐line particle counting was successfully used in a 0.5 × 106–m3/d (135‐mgd) conventional water treatment plant to distinguish the effects on water quality of small changes in coagulant dosage and filter flow. Measurable changes in particle counts in filtered water were detected when the aluminum sulfate dosage ranged from 5 to 10 mg/L at filter loading rates of 4–9.5 m/h (1.7–4.0 gpm/sq ft). Particle count percentile plots and statistics (10th, 50th, 90th, 95th, and 98th percentiles) were valuable indicators of the performance of both individual filters and the overall plant.
European regulations on residual disinfection
Authors: Hydes Owen 
Published: February 2018

Even though European countries vary in their disinfection practices, they must hit the same microbiological targets set by a formal drinking water directive.This article describes the relevant requirements of the European Community Drinking Water Directive and outlines how the European Union's 15 member states and Switzerland have implemented them. European countries vary considerably in their national requirements or guidance on disinfection and the use of disinfectant residuals within the distribution system. Although a few European countries require all water supplies to be disinfected and a disinfectant residual to be maintained, some countries do not require disinfection or the use of a disinfectant residual. Some countries adopt intermediate positions, and many countries have exceeded the directive's requirements. A number of factors influence countries' practices, including the nature and quality of their water sources, meteorological conditions, the degree of treatment provided to remove impurities, concern about disinfection by‐products, and the operation and condition of the distribution system. A recently agreed on new Drinking Water Directive is also described.
Surfing the Web for water quality data
Authors: DeNileon Gay Porter 
Published: February 2018

Water quality information on the Internet is increasing every day, but questions persist about the data's reliability, accessibility, and timeliness.The Internet offers water professionals widespread opportunities to disseminate and obtain water quality data. As part of a US Environmental Protection Agency pilot project, the Des Moines (Iowa) Water Works is posting its finished water quality data in real time on the World Wide Web. Some utilities have also instituted Web sites; others are still in the process of determining the type and extent of information to post on the Internet. This article cautions water professionals about the pitfalls associated with cyberspace data—notably inaccuracy and inaccessibility— and briefly describes the major sites providing water quality information.
Ferric chloride plus GAC for removing TOC
Authors: Nowack Kirk O. , Cannon Fred S. , Arora Harish 
Published: February 2018

Ferric chloride extends GAC bed life and prevents calcium buildup.Granular activated carbon (GAC) treatment is one method that water utilities can use to increase removal of natural organic matter and comply with the recently promulgated Disinfectants/ Disinfection By‐products Rule. The cost of GAC depends on its useful service life and its capacity for reuse. The research reported here used minicolumns to investigate how ferric chloride coagulation influenced the total organic carbon (TOC) subsequently removed by GAC. Ferric chloride pretreatment lengthened GAC bed life by lowering influent TOC and by rendering the TOC that remained more adsorbable. Jar tests showed that at pH < 6.0, ferric chloride was superior to aluminum salts, on an equimolar basis, for removing TOC.
Arsenic treatment considerations
Authors: Chen Hsiao‐wen , Frey Michelle M. , Clifford Dennis , McNeill Laurie S. , Edwards Marc 
Published: February 2018

The least‐cost method of removing arsenic may not be the best method all around.The best arsenic treatment technique for a given utility will depend on arsenic concentration and species in source water, other constituents in the water, existing treatment processes, treatment costs, and handling of residuals. To evaluate these issues, a national survey investigated arsenic occurrence and speciation in US drinking water sources. In general, total arsenic concentration was higher in groundwater than in surface water supplies. Particulate arsenic was more abundant than previously suspected, and more arsenate than arsenite was present. The cost of arsenic treatment increased in the following order: modified conventional treatment << activated alumina or anion exchange < reverse osmosis. Nevertheless, the most cost‐effective treatment still might not be best, because secondary treatment benefits and residuals handling should also be taken into account.
Benefits and costs of the IESWTR
Authors: Regli Stig , Odom Rosemarie , Cromwell John , Lustic Mike , Blank Valerie 
Published: February 2018

This new rule's costs are likely to be outweighed by its benefits, including reduced endemic risk from exposure to Cryptosporidium and improved public health.Like the Stage 1 Disinfectants/Disinfection By‐products Rule, the Interim Enhanced Surface Water Treatment Rule (IESWTR) grew out of the negotiated rulemaking the US Environmental Protection Agency convened in 1992–93 under the Federal Advisory Committee Act (FACA). The rulemaking sought to develop a consensus approach to simultaneously addressing potential health risks posed by disinfection by‐products (DBPs) and waterborne pathogens. Even though the process was complicated by (1) the possibility of making inadvertent risk–risk tradeoffs between protection from DBPs and protection from pathogens and (2) uncertainties affecting the assessment of both risks, the regulatory‐negotiations committee was able to devise a well‐balanced, staged approach to regulation. A second FACA committee finalized the approach in 1996–97. This article summarizes the microbial side of the benefit–cost analysis and the explicit uncertainty analysis that was used to inform the stakeholders and the negotiators.
Helping operators improve plant performance
Authors: Booth Susan K. , Hagar C.B. , Goss Randy J. , Lippe J. Chris , Schulze Jean A. 
Published: February 2018

A process assistance system empowers operators to make decisions and take ownership of the plant during their shifts.The City of Austin (Texas) Water and Wastewater Utility consistently produces drinking water of the highest standards. But with the development of more and tougher regulations, water treatment has become more complex for operators. Utility managers recognized that although it is necessary to provide advanced computer systems, instrumentation, and traditional operations training, these elements alone are not sufficient to meet the utility's stringent internal optimization goals. Operators also need to be able to recognize and respond promptly to developing process problems. Utility managers realized that operators would benefit from readily available plant‐specific process guidance and envisioned a process assistance system (PAS). Written in Web‐page format, the PAS is designed to help operators interpret data and improve their decision‐making skills. It was developed through in‐depth investigations of operators' actions and treatment decisions during routine and nonroutine operations. The PAS will also be used as a tool for training, performance assessment, and operator accountability.
Influence of NF on distribution system biostability
Authors: Escobar Isabel C. , Randall Andrew A. 
Published: February 2018

In a 12‐month study, nanofiltration achieved high percentages of BDOC removal but was less effective in reducing AOC concentrations.When biodegradable organic matter is not removed during water treatment, bacteria may proliferate in the distribution system. This bacterial growth can deteriorate water quality, accelerate pipe corrosion, and potentially increase the incidence of bacteriological diseases. This project's main objective was to collect and analyze full‐scale system data on long‐term results of nanofiltration (NF) with respect to its effect on bacterial regrowth potential as quantified by assimilable organic carbon (AOC) and biodegradable dissolved organic carbon (BDOC). One of the major observations over the sampling period was that NF had a strong effect on the BDOC concentration of the treated water. In contrast, NF did not reject the major fraction of AOC, which leaves NF's effect on biostability open to question.
Reusing rinse wastewater at a semiconductor plant
Authors: Shah Ajay R. , Ploeser Jane Heller 
Published: February 2018

Two pilot projects for recycling and reusing rinse wastewater pay off by substantially reducing water consumption and costs.Two pilot rinse wastewater reuse projects were developed as part of a long‐term water conservation program for a Motorola semiconductor manufacturing site in Phoenix, Ariz. The conceptual designs for the projects grew out of a detailed wastewater reuse study that characterized wastewater streams at their generation points. Both treatment techniques were specifically researched, bench‐tested, and adapted to further water conservation efforts while ensuring 100 percent compliance with appropriate effluent regulations and industrial discharge permit conditions. Together, the pilot projects save the city of Phoenix approximately 45 mil gal (17 × 104 m3) of water annually.
Using conservation rate structures
Authors: Jordan Jeffrey L. , Albani Rick 
Published: February 2018

A survey of water suppliers using conservation rate structures offers insight into the efficacy of pricing as a conservation incentive.The authors developed a survey to learn about water providers' experiences using conservation rate structures. The survey included questions about service characteristics, demand levels before and after implementation of conservation rates, rate structures and price levels, billing and revenue, other conservation measures, and the objectives and effectiveness of rates and conservation efforts. Drawing on a number of respondent pools, the authors distributed the survey to 567 utilities and received 89 responses. This article represents a first step in evaluating the effect of conservation rate structures and gives water professionals a closeup look at the use of pricing in utility conservation efforts.
Fluoride concentrations in drinking water
Authors: Lalumandier James A. , Jones Jackie L. 
Published: February 2018

A study was undertaken to determine how closely optimal fluoride concentrations reported by states matched US Public Health Service recommendations.The US Public Health Service sets optimal fluoride concentrations for community water supplies. The agency's recommendations were used to create a fluoridation map of the United States depicting optimal concentrations. This study determined how closely reported state optimal fluoride concentrations followed those on the map. The most recent fluoridation census statistics were used to determine the reported state optimal fluoride concentration, which represents the level at which community water supplies should be fluoridated according to state policy. In only five states did the reported state optimal fluoride concentrations exactly match those on the fluoridation map. Eleven states reported lower state optimal fluoride concentrations on average; 32 reported higher amounts. As research and debate continue regarding optimal fluoride concentrations in drinking water, it is important that water plant operators stay current on fluoridation issues.
Multiple benefits of reengineering
Authors: Gritzuk Michael , Janis Wayne S. , Blundon Edward G. , Myers Joe 
Published: February 2018

At a major Arizona utility, employee teams tackle an ambitious reengineering process, reaping significant savings and other benefits.In 1995, the Phoenix, Ariz., Water Services Department embarked on a reengineering process to change its organizational structure, improve work practices, and enhance its technology. The utility transformed the way it runs its business by instituting a changed culture of empowered and responsible employees, self‐directed work teams, employee‐developed work practices, enhanced technology, and a new model for cooperation among employees, union, and management. As a result of the reengineering process, the utility was able to reduce staff without any layoffs (and despite continued growth) and achieve first‐year savings of $3 million.
Bioavailability of Al in alum‐treated drinking water
Authors: Stauber Jennifer L. , Florence T. Mark , Davies Cheryl M. , Adams Merrin S. , Buchanan S. John 
Published: February 2018

In healthy people, Al uptake from alum‐treated water is low.Several epidemiological studies have associated aluminum (Al) in drinking water with the incidence of Alzheimer's disease, despite the fact that water provides a relatively minor proportion of intake compared with other dietary sources. For Al from alum‐treated drinking water to contribute markedly to blood Al, it would have to be much more bioavailable, i.e., more readily taken up from the gut into the bloodstream, than Al from food. The relative bioavailabilities of Al naturally present in food and in alum‐treated drinking water (ATW) were determined using 29 healthy volunteers who drank, during two‐day periods, ATW or pure water, with and without citrate, while on a controlled diet. Only 1–2 percent of the daily intake of Al came from ATW and only 0.3–0.4 percent of the Al in ATW was absorbed by the body—the same percentage as that absorbed from food. It was estimated that drinking 1.6 L/d of ATW containing 140 μg/L Al would contribute only 0.4–1.1 percent of the lifetime body burden of Al.
Estimating the porosity of a full‐scale anthracite filter bed
Authors: Trussell R. Rhodes , Chang Melissa M. , Lang John S. , Hodges Willie E. 
Published: February 2018

Typical pilot studies may slightly underestimate clean‐bed head loss in full‐scale filter beds.The weight of media per unit of filter area cannot be directly measured in a full‐scale filter bed as it can be in a pilot‐scale filter column. Thus the porosity of a full‐scale bed of filter media cannot be readily calculated, and determinations of the porosity in full‐scale filters are rarely reported. In this study the porosity of one full‐scale monomedia filter bed was estimated by comparing the head loss in a full‐scale filter with the head loss in a pilot‐scale filter, when both used the same anthracite media. The full‐scale filter contained uniform anthracite media with an effective size of 1.5 mm loaded to a depth of 6 ft (1.8 m). The gradual termination of the backwash flow produced more consistent porosities in pilot‐scale filter beds. The porosity of the full‐scale filter bed was about 48 percent, somewhat lower than that expected in pilot‐scale columns. Thus, full‐scale designs based on pilot data may underestimate clean‐bed head loss.
Forces transforming the water business
Authors: Shorney Frank L. 
Published: February 2018

The global economy, burgeoning populations, and rapidly evolving information technologies are changing the way the water industry does business.To stay competitive in today's business environment, the water profession must adapt to dynamic forces that are transforming societies worldwide. In the area of commerce, local and national borders are vanishing, replaced by a global economy. Populations are booming in undeveloped countries and shrinking elsewhere. The Internet provides instant information to a worldwide audience, all potential consumers of the new e‐commerce. The challenge to the water industry is to adjust to meet these developments by incorporating appropriate technology as it develops, forging better employee–management relationships, and improving customer service and communication.