bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using flow cytometry to detect protozoa
Authors: Hoffman Rebecca M. , Standridge Jon H. , Prieve Audrey F. , Cucunato Joseph C. , Bernhardt Mat 
Published: February 2018

For routine detection of Cryptosporidium and Giardia, flow cytometry with cell sorting bests IFA in terms of relative sensitivity as well as average cost, assay volume, assay time, and turnaround time.Flow cytometric cell sorting (FCCS), followed by microscopic verification, was evaluated as an alternative to immunofluorescence assay (IFA). Two hundred and sixty‐two water samples were stained with either indirectly conjugated or directly conjugated anti‐Cryptosporidium and anti‐Giardia antibodies and were examined by IFA and FCCS, respectively. Relative sensitivities of each assay were calculated by dividing the number of positive samples detected by one assay by the number of positive samples detected by either assay. When samples analyzed within five months of the initial IFA analysis were compared, the relative sensitivities of FCCS for detection of Cryptosporidium and Giardia were 94.1 and 78.6 percent, respectively, whereas the relative sensitivities using the IFA were 35.3 and 61.4 percent. Identification of Cryptosporidium and Giardia in water samples using FCCS takes less time, costs less, and analyzes a greater sample volume than the IFA. Given the nearly threefold increase in relative sensitivity for Cryptosporidium detection and the equal relative sensitivities for Giardia detection, the authors support the use of FCCS for routine detection of Cryptosporidium and Giardia in environmental samples.
Comparative performance of Colisure
Authors: McFeters Gordon A. , Broadaway Susan C. , Pyle Barry H. , Pickett Molly , Egozy Yair 
Published: February 2018

Colisure, an enzyme detection–based medium, outperformed established reference methods in detecting chlorine‐stressed total coliform bacteria and E. coli.Colisure presence–absence medium was compared with standard reference methods for detecting low numbers of total coliform bacteria and E. coli in drinking water when the bacteria were subjected to chlorine stress. When Colisure was compared with established reference methods to detect total coliforms in dilute, disinfected samples, Colisure yielded more positive results after 24, 28, and 48 h than lauryl tryptose broth (LTB) confirmed in bile green lactose broth after 48 h. Colisure also detected higher levels of chlorine‐injured E. coli than LTB confirmed in EC medium with 4‐methylumbelliferyl B‐D‐glucuronide (EC/MUG). The sensitivity and specificity of Colisure were also evaluated and were determined to be between 96 and 100 percent on nonchlorinated samples when positive and negative tests were verified.
Effect of iron and sulfur on thermal regeneration of GAC
Authors: Cannon Fred S. , Snoeyink Vernon L. , Lee Ramon G. , Dagois Gerard 
Published: February 2018

Iron accumulations on coal‐based GAC or wood‐based GAC had little or no catalytic influence on regeneration behavior during the first regeneration cycle.Regeneration of spent granular activated carbon (GAC) can be affected by inorganics that have accumulated by ion exchange on specific GAC sites, precipitation, or adsorption of metal‐organic complexes. The authors found iron (Fe) in several spent GAC samples. Sulfur (S) always appeared in these GAC samples as well. Although Fe catalyzes the gasification of GAC to oxides of carbon, Fe catalysis of GAC gasification experienced dramatic inhibition by S at concentrations as low as 100–300 mg S/kg GAC (0.01–0.03 percent). When S was reduced to 20 mg S/kg GAC, the Fe at 1 percent loading became a strong catalyst. Because S is usually present in spent GACs at concentrations that inhibit catalysis, thermal regenerations behaved essentially the same whether Fe was present or absent.
USEPA's infrastructure needs survey
Authors: Davies Clive , Fraser Dan L. , Hertzler Patricia Carroll , Jones Ralph T. 
Published: February 2018

USEPA estimates that water systems need $138 billion to install, upgrade, or replace infrastructure. Only $12.1 billion of that total is attributable to requirements of the SDWA.The nation's 55,000 community water systems must make significant investments to install, upgrade, or replace infrastructure to ensure the provision of safe drinking water to their 243 million customers. The US Environmental Protection Agency's first‐ever national drinking water infrastructure needs survey, conducted in 1995, estimates that these systems must invest a minimum of $138.4 billion in the next 20 years. Of this total, $76.8 billion is for infrastructure improvements needed now to protect public health. A portion of the total, $12.1 billion, is for infrastructure improvements related to standards established under the Safe Drinking Water Act.
Assessing the value of youth education
Authors: Mirvis Kenneth W. , Clark Neil 
Published: February 2018

An informal survey of 10 water organizations yields some compelling reasons for funding youth education programs.The authors conducted informal research—questionnaires and interviews—with nine water agencies and one water education organization to ascertain the value, variety, and goals of school education programs. They found a broad range of programs covering every grade level and many messages. These agencies used a range of measures to assess the value of their programs, including quantifying the number of students reached and attempting to measure changes in student behaviors. The costs of these programs were surprisingly low, ranging from 5ȼ to 57ȼ per household per year, with an average of only 24ȼ per household per year. Despite little agreement about what school programs should be, the organizations agreed on the programs' long‐term value to the agency and the community and concurred that youth education programs provide an excellent opportunity for outreach.
Automatic meter‐reading is not always economical
Authors: Bienlien Kent D. , Burns Larry D. 
Published: February 2018

Automatic meter reading has benefited some utilities economically, but a cost–benefit review of such systems should be performed.Automatic meter reading (AMR) is promoted as a way to use electronic technology to reduce the cost of customer service and meter‐reading. Manufacturers provide a wealth of technical data about hardware and software for AMR, but objective reviews of the current systems' economic feasibility are also needed. A nine‐month trial of three manufacturers' AMR systems was conducted in Lexington, Ky., to determine the cost‐effectiveness of radio‐frequency hand‐held meter‐reading equipment. All three systems accurately read meters in pits at distances up to 500 ft (150 m). Economic justification inherently varies significantly from site to site. For the site described in this article, economic analysis indicated that installation of the most economical system would increase the cost of each meter read by $0.22.
Water affordability and the DWSRF
Authors: Beecher Janice A. , Shanaghan Peter E. 
Published: February 2018

The DWSRF provides a potentially important means of mitigating the affordability problem.The Drinking Water State Revolving Fund (DWSRF) was established under the 1996 Safe Drinking Water Act (SDWA) to provide financial assistance to water systems that cannot afford to make improvements that would allow them to comply with regulatory standards. Disadvantaged communities are also targeted for aid under the DWSRF. But to implement the provisions of the SDWA, states must adopt affordability criteria for use in their DWSRF programs. “Affordability” is the term used to describe the ability of a water system and its customers to support the cost of compliance. Although a considerable amount of research has been conducted on affordability, no simple solution has emerged. This article describes a framework for understanding the multidimensional issue of affordability.
Metric benchmarking
Authors: Blankenship Linda , Olstein Myron , Liner Barry 
Published: February 2018

Benchmarking is becoming a popular tool for utilities to systematically assess how their performance compares with that of other utilities, so that trouble spots can be targeted.In recent years, benchmarking has gone from a buzzword in the water industry to a useful tool to assess performance. The AWWA Research Foundation has funded two studies of benchmarking, is sponsoring expansion of WaterStats into a database that can support benchmarking efforts, and has defined two forms of benchmarking—metric benchmarking and process benchmarking. Metric benchmarking, more commonly used by water suppliers, involves tracking operations over time and comparing the performance against that of similar companies within one industry. Process benchmarking breaks system processes into individual steps and then compares these process elements with those of the best practice providers from any field. For water utilities, benchmarking is particularly useful in five distinct applications: management review, strategic planning, outsourcing of services, reports to management, and system acquisition.
Activity‐based costing
Authors: Eggers John L. , Bangert Charles E. 
Published: February 2018

Activity‐based accounting provides a true measure of services and goods and helps target business processes that need improvement.The water supply industry must respond to the competitive challenges of the current business climate by promoting efficiency and lowering costs. Many techniques are available to help managers decrease costs and increase productivity and customer service. None of these methods will work, however, unless an organization can identify and measure the cost and performance of the activities that constitute its core business processes. Activity‐based costing (ABC) is proposed as a methodology for measuring and managing gains in process efficiency. A proven operational technique, ABC measures the cost of activities, provides true costs of goods and services produced, and tells a manager where to look to improve business processes and employee performance, reduce costs, and enhance the quality of products produced and services performed.
Spreadsheet water conditioning
Authors: Trussell R. Rhodes 
Published: February 2018

Spreadsheets are a powerful tool for solving water chemistry problems.Procedures for solving problems of equilibrium chemistry are demonstrated through the use of spreadsheet calculations. For most simple problems, these calculations are less costly and more reliable than bench‐scale testing. Once such a spreadsheet has been constructed, it can be reused without duplicating the original effort. Spreadsheet technology makes calculations of this sort accessible to more users than the traditional methods.
Managing water supply infrastructure
Authors: Burlingame Gary A. , Rahman Jameel , Navera Edgar , Durrant John E. 
Published: February 2018

Materials engineering offers water suppliers services beyond routine testing and failure investigation.As it relates to the treatment and supply of drinking water, materials engineering is not limited to the investigation of failures and routine testing of samples for compliance with purchase specifications. Materials engineering can be used to rewrite material specifications, coordinate vendor surveillance, provide predictive testing to prevent failures, and consult on new designs. If water suppliers are to continue to provide high‐quality water with greater reliability in the quantity desired at an affordable cost, the US drinking water industry must make greater use of materials engineering and become more involved in materials engineering discussions and research. By sharing the experiences of the Philadelphia (Pa.) Water Department, the authors hope to encourage technology transfer in materials science and technology among water suppliers.
Agricultural chemicals: effects on wells during floods
Authors: Ray Chittaranjan , Soong T.W. David , Roadcap George S. , Borah Deva K. 
Published: February 2018

A radial‐arm collector well was at more risk than vertical wells, but MCLs were not exceeded in any well.A 175‐mi (282‐km) stretch of the Illinois River was studied to assess the potential effects of flooding on the quality of pumped groundwater. Water pumped from four municipal water supply wells (pumping rates, 140‐500 gpm [0.009‐0.03 m3/s]) was analyzed. Three of these wells were vertical wells located 175‐220 ft (53‐67 m) from the river's edge at normal pool stages. The fourth well was a radial‐arm collector well with laterals extending beneath the river bed. Although concentrations of atrazine in the Illinois River during peak flows of 1995 and 1996 were as high as 6 and 12 μg/L, respectively, the concentration of atrazine in groundwater pumped at the three vertical‐well sites remained below the 0.1‐μg/L detection limit. In 1996 a small breakthrough of atrazine was observed in the collector well water. The high concentration of nitrate in river water appeared to have slightly increased the nitrate in pumped groundwater at two locations. Dilution and other factors may have affected the transport of river water contaminants in the alluvial aquifer between the river and the pumping wells.
Blending supplies for plant optimization
Authors: Booth Susan K. , Hagar C.B. , Garaña Eduardo , Hall Herbert R. 
Published: February 2018

When water supplies are combined, a blend based on a target source water parameter rather than quantity alone can help optimize plant performance.The Corpus Christi, Texas, water treatment plant treats water from the Nueces River watershed. In the fall of 1998, the plant will begin receiving water from Lake Texana, a source with very different water quality. A comprehensive treatability study was conducted to prepare the plant for the new water. In evaluating the desirability of treating a given blend and selecting an optimum blend to target for treatment, the authors considered several factors, e.g., amount of chemicals required, range in chemical dosages required, settled and filtered water quality, and compliance with the proposed enhanced coagulation regulations. The authors proposed that the optimal blend for Corpus Christi be identified by alkalinity and achieved by targeting a range of alkalinity in the raw water. In general, selection of a blend based on a target source water parameter may result in creation of a more consistent source water than is achievable by blending based on quantity alone, thereby increasing the potential for optimizing plant performance.
Implementing a large‐meter replacement program
Authors: van der Linden Matthew J. 
Published: February 2018

A comprehensive large‐meter replacement program can help utilities avoid revenue losses caused by malfunctioning meters and increase reliability of service to customers.Each year, thousands of dollars in revenue are lost because of malfunctioning large water meters. Implementing a large‐meter replacement program is critical to the financial health of any water utility. A large‐meter replacement program provides procedures to systematically and continuously replace or repair aging and malfunctioning large meters. The benefits of such a program include accurate accounting of water consumption to maximize revenues and reliable service to customers.
Practical applications of turbidity monitoring
Authors: Burlingame Gary A. , Pickel Michael J. , Roman Joseph T. 
Published: February 2018

To take the use of turbidity measurements to a level at which accuracy is critical without the support of quality assurance‐quality control would be inappropriate.The Philadelphia Water Department (PWD) has expended considerable effort to achieve a voluntary 0.1‐ntu turbidity goal. This was motivated in large part by heightened concern about Cryptosporidium, by the expectation of changes in regulatory requirements under the Safe Drinking Water Act, and by voluntary participation in the Partnership for Safe Water. This article summarizes PWD's understanding of, concerns about, and perspectives on the practical applications of turbidity monitoring.
Using need‐to‐know criteria to design training
Authors: Delvecchio Fred 
Published: February 2018

Need‐to‐know criteria and instructional systems design methods can help prepare operators to protect public health.The Safe Drinking Water Act Amendments of 1996 recognize that training and certification contribute to achieving public health and water quality goals. Water facility managers and operators, regulatory personnel, training program managers, and instructors have a stake in the success of training and certification. Certification and training share purposes and methods. Instructional systems design methods and principles can be used to develop effective training and certification examinations. Need‐to‐know (NTK) criteria developed by the Association of Boards of Certification to design certification examinations can serve as a beneficial starting point to identify training needs. NTK criteria are derived from job tasks and the apabilities necessary to accomplish those tasks. Thus, certification that is based on NTK criteria should effectively measure a person's abilities and training. The end result should be competent operators who are able to perform essential job skills.
Cross‐training benefits Oregon plant
Authors: Wise Doug 
Published: February 2018

Even in an emergency, this strategy empowers fewer operators to handle more responsibilities effectively and efficiently.Labor is often the single most expensive component of water treatment operations and water quality monitoring. By fully cross‐training operators in plant operations, maintenance of structures and equipment, and certified laboratory sampling and analyses, any utility can ensure that its employees have the technical capability to complete water production and water quality monitoring tasks cost‐effectively. A fully integrated program that requires operators to complete advanced training, maintain the highest possible certification, and manage diverse responsibilities usually reduces the number of staff positions required at a plant site. Job interest is increased by providing regular shift rotation and varied tasks. Cross‐training typically promotes long tenure because of the resulting job satisfaction. This combination of skill, experience, and responsibility works well during normal operations but proves to be vital during abnormal operations or emergencies, such as the record flooding in Oregon in February 1996.
Operator training: a step‐by‐step approach
Authors: Kerri Kenneth D. 
Published: February 2018

Effective training matches learning needs and objectives with the right mix of instruction methods and technologies.This article describes how to identify operator training needs, define training program objectives, evaluate training methods, and select appropriate methods and technologies. Program planning considerations include operators' availability for and attitudes toward training programs, instruction methods and technologies, time constraints for completing training, and costs. The basic modes of instruction are classroom lectures and home‐study or self‐study programs. Work‐related training programs include apprenticeships, internships, on‐the‐job training, and technical assistance. Instruction can be enhanced by the use of written training materials, videos, compact disks with read‐only memory, interactive computers, and computer simulation games. Operator trainers and utility agencies need to evaluate each training program after it is completed; they should also develop a long‐term strategy to evaluate the effectiveness of the overall training effort and to improve future training programs.
BOM removal during biofiltration
Authors: Carlson Kenneth H. , Amy Gary L. 
Published: February 2018

Although the biofiltration process may not control the design of a filter bed, results described here can help the engineer better understand the tradeoffs.Pilot‐scale biofiltration experiments were conducted to determine how empty bed contact time (EBCT) and hydraulic loading rate (HLR) affected the removal of biodegradable organic matter (BOM). The removal of BOM formed during ozonation was measured as the reduction (resulting from biodegradation) of dissolved organic carbon in the filter; it was referred to as biodegradable dissolved organic carbon–filter (BDOCfilter). Ten ozone by‐products were measured to understand the composition of BDOCfilter and to assess whether these by‐products might be used as a surrogate for BOM; none sufficed. BOM formed during ozonation limited the removal of BDOC during biofiltration with two exceptions: nonsteady‐state BOM loading conditions and inadequate EBCT. Both of these conditions were limited by biomass formation. HLR had no effect on BDOCfilter even though markedly different biomass profiles were observed.
Preparing utility computer systems for the year 2000
Authors: Ladner Robert L. , Leake Gary A. 
Published: February 2018

Making the transition to the new millennium represents a real threat to water utility operations until a compliance program is completed.On Jan. 1, 2000, some 80 million computers around the world will attempt to process a 00 year. Without year 2000 (Y2K) compliance assured, some computers will crash, some programs will halt, and others will create countless errors. Worse yet, some programs will produce slightly errant or corrupt data that will be assumed valid because the errors will not be readily detected. Utilities can take strategic steps to ensure that their computer systems are immune from Y2K‐related problems. This article discusses the Y2K problem and presents a methodology utilities can follow to take corrective action.
Converting utility data for a GIS
Authors: Cannistra James R. 
Published: February 2018

To be effective, a geographic information system must be created with its intended use, available source materials, and budget considerations in mind.Most utilities throughout the United States and abroad are planning or implementing an automated mapping–facilities management–geographic information system. The database acquisition and conversion process is typically the most expensive and time‐consuming part of implementing such a system. Many agencies convert water or sewer facility data immediately after a land and parcel database is developed. This article highlights the key technical issues associated with creating a geographic information system database to support water utility operations and applications. It describes database concepts and provides an overview of the data conversion process. Alternative approaches for developing a base map and converting water facility data are described, and technical issues relating to accuracy, symbology, feature content, conversion methodologies, and quality control are discussed.
Committee Report: Design and installation of PE pipe
Authors:   AWWA Polyolefin Pressure Pipe Fittings Committee
Published: February 2018

PE piping made in accordance with AWWA C906‐90 is a sturdy, tough, and durable material ideal for direct burial, no‐dig, and marine installations.The AWWA Polyolefin Pressure Pipe and Fittings Committee is developing a manual that will focus solely on the design and installation of polyethylene piping made in accordance with AWWA C906‐90. Because development will take at least another year, the committee has produced this report to provide guidance on properly designing and installing PE materials in the meantime. This report discusses the composition and properties of PE piping, including its density, toughness, and ductility; outlines major applications for the material; presents essential design criteria; and offers guidelines on joining, installing, and pressure‐testing PE pipe. A section on marine installations covers selecting an appropriate site and assembling, launching, and submerging pipe.