bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterizing Surface Waters That May Not Require Filtration
Authors: Geldreich Edwin E. , Goodrich James A. , Clark Robert M.
Published: February 2018

Field data from various utilities were studied with the object of identifying a set of characteristics of a surface water that might allow it to be successfully treated by disinfection alone, thus avoiding the need to filter. It was found possible to define water quality standards for a surface water amenable to disinfection only: fecal coliforms—20/100 mL, turbidity—1 ntu, color—15 acu, and chlorine demand—2 mg/L. As well as meeting specifications for raw‐water quality and monitoring, a utility would also need to meet certain conditions for system operations.
Performance and Analysis of Tracer Tests to Determine Compliance of a Disinfection Scheme With the SWTR
Authors: Teefy Susan M. , Singer Philip C.
Published: February 2018

The Surface Water Treatment Rule (SWTR) contains tables of disinfectant CT(concentration × time) values that have been demonstrated to achieve the required degree of inactivation of viruses and Giardia cysts. If the CT product for a water treatment plant meets or exceeds those in the SWTR tables, it is assumed this inactivation has been achieved. The objective of the study was to compare two methods for calculating C and T. Tracer tests were conducted to characterize the behavior of flow through the process units of water treatment plants. Effective CT values, which were calculated based on the residence time distribution and the kinetics of chlorine decay, were compared with the most conservative CT values recommended in the US Environmental Protection Agency guidance manual.
Environmentalism in the Water Industry
Authors: Sedam Stephen , Burgins Scott , Moser Richard H. , Tenny Edward , DeBoer Jon , Reeves Merilyn B.
Published: February 2018

This discussion took place June 20, 1990, at the AWWA Annual Conference. Panel moderator was Jon G. DeBoer, director of AWWA's technical and professional department. Participants were: Scott Burgins, environmental reporter, Cincinnati Enquirer. 617 Vine St., Cincinnati. OH 45201; Richard H. Moser, vice‐president‐water quality. American Water Works Service Co. Inc., 1025 Laurel Oak Rd., Voorhees, NJ 08043: Merilyn B. Reeves, environmental activist. League of Women Voters, 22250 Boulder Crest Lane S.E., Amity. OR 97101; Stephen Sedam. executive director. Ohio Environmental Council, 22 E. Gay St., Columbus, OH 43215; and Edward Tenny, administrator. Portland Water Bureau. 1120 S. W. 5th Ave., Portland. OR 97204.
Expert Systems in Water Treatment Plant Operation
Authors: Nix Stephan J. , Collins Anthony G.
Published: February 2018

Expert systems are an emerging technology with potential benefit for the water industry. This article focuses on the types of applications possible in water treatment plants and some of the practical issues of design and implementation. Prototype expert systems for the operation of two upstate New York treatment plants are described. Based on experience gained in developing these prototypes, the potential value of expert system technology in water treatment is assessed.
LETTERS
Authors: Olson Betty H.
Published: February 2018

Olson responds to a letter by J.L. Cohoon, chief executive officer of Access Analytical Systems, the company that manufactures the Colilert MMO‐MUG test for coliform (“Olson's Allegations Refuted,” Journal AWWA, January 1991). Cohoon was responding to a report on Olson's research, which showed that two MMO‐MUG preparations performed poorly in detecting E. coli in treated waters (“Update–Researcher Challenges Efficacy of E. coli Analytical Technology,” Journal AWWA, September 1990). Olson addresses several criticisms in Cohoon's letter. Olson asserts that the only unusual aspect of her study is that it was the first to challenge the performance of the Colilert media–most likely because the study was designed to eliminate a bias in published reports that did not allow for assessment of the possible occurrence of false‐negative results. More studies are needed to evaluate the performance of Colilert and other products in detecting low concentrations of injured E. coli.
Trihalomethane Formation in Open Reservoirs
Authors: Karimi Ali A. , Singer Philip C.
Published: February 2018

Historical records were used to characterize the quality of water in an open distribution reservoir with respect to trihalomethanes (THMs) and total organic halides and to explore the effect of algae, chlorine use, and reservoir bypass operation on THM formation.
Measuring Low Radon Levels in Drinking Water Supplies
Authors: Lowry Jerry D.
Published: February 2018

Because a relatively low maximum contaminant level (approximately 300 pCi/L) is expected to be set for radon in the near future, research was conducted with liquid scintillation counting to determine whether this method of analysis could be used for low levels of radon. Counting with an optimized window and an optimized water‐to‐fluor ratio resulted in achievement of a lowest quantifiable level of 150 pCi radon/L. Lower levels can be quantified using a longer counting period.
Applying Ozone for Organics Control and Disinfection: A Utility Perspective
Authors: Ferguson David W. , Gramith Jill T. , McGuire Michael J.
Published: February 2018

Ozone can be used for a variety of purposes in the treatment of drinking water. This article provides an overview of three interrelated ozone applications—disinfection by‐product control, organics removal, and disinfection—along with the key issues affecting each. In addition to summarizing the literature, the article describes the results of bench‐ and pilot‐scale studies performed by the Metropolitan Water District of Southern California. Research needs are identified.
Bromoform and Iodoform Formation Potential Tests as Surrogates for THM Formation Potential
Authors: Reckhow David A. , Edzwald James K.
Published: February 2018

Several bromoform and iodoform formation potential tests were evaluated for use as surrogates for trihalomethane formation potential (THMFP). Although these tests are generally faster and simpler than the THMFP test, some were very difficult to perform, and others gave inaccurate results. Based on analyses of raw and treated drinking waters, the 2‐h standard iodoform formation potential test appeared to be the most useful. This test proved to be a better surrogate for THMFP than dissolved organic carbon, and it was equally as accurate as UV absorbance.
Reselling and Vending Water
Authors: Katko Tapio S.
Published: February 2018

Until recently the reselling and vending of water in the developing world has largely been ignored by utilities, governments, and external support agencies. Owners of private connections resell water to customers who come and fetch it. Vendors transport water door‐to‐door or sell it wholesale. Reselling and vending indicate consumers' ability and willingness to pay for water service. Recent examples and two case studies suggest that these practices can be used as design criteria for utility services, especially for peri‐urban areas.
The New Lead and Copper Rule
Authors: Pontius Frederick W.
Published: February 2018

Articles in this section of the JOURNAL are dedicated to providing current information about legislative and regulatory developments relating to the water industry. They address needs and concerns of water utilities from a practical standpoint; they are not intended to reject official positions OY policies ofthe association. Frederick W. Pontius, AWWA associate director fir regulatory affairs, prepared this discussion regarding 2he newly promulgated Lead and Copper Rule and coordinates development offuture articles. Pontius monitors and evaluates legislation and regulations that affect the water industy, prepares oficial AWWA statements on drinking water issues, and represents the association at meetings, workshops, and study groups.
Reliability Analysis for Master Planning of a Water System
Authors: Harberg Robert J. , Macy Peter P.
Published: February 2018

The reliability of urban water systems is coming under greater scrutiny as increased public demand continues to stretch the systems' capabilities. In many cases the public has taken for granted the reliability of these systems. However, as more attention is turned to the cost and environmental consequences of developing new urban water supplies and facilities, the question of reliability must be more thoroughly addressed. This article presents an example of such a reliability analysis applied to a water delivery system and describes how the City of Boulder, Colo., used this analysis to determine the need for and priority of water system improvements.
Mechanical Dewatering of Alum Solids and Acidified Solids: An Evaluation
Authors: Bishop Mark M. , Cornwell David A. , Rolan A. T. , Bailey Thomas L.
Published: February 2018

The city of Durham, N.C., performed full‐scale testing of alum recovery from alum sludge generated in a 22‐mgd water treatment plant. Purposes of the tests were to determine the technical feasibility of mechanical dewatering of acidified alum solids and to develop design data. Three mechanical dewatering devices—a belt press, a centrifuge, and a diaphragm filter press—were screened in bench‐scale tests. The belt press did not warrant further testing. Manufacturers of the centrifuge and the filter press then conducted dewatering tests at the treatment plant. Tests showed that with proper chemical conditioning, both devices could be successfully used to dewater acidified solids to 30 percent or more. Recovered alum is proposed for two uses in Durham: as a coagulant in the water plant and as a phosphorus‐removal chemical in one of the city's wastewater treatment plants. Recovering and recycling alum can significantly lower final sludge disposal costs, which are increasing as more restrictive solid waste regulations take effect.
Laboratory Comparison of DAF With Conventional Treatment
Authors: Malley James P. , Edzwald James K.
Published: February 2018

Dissolved‐air flotation (DAF) was compared with conventional gravity settling (CGS) in laboratory experiments using synthetic water and in field studies using alum and polyaluminum chloride. DAF produced significantly lower residual turbidities than did CGS, particularly at colder temperatures. The difference in performance between DAF and CGS is explained using the particle size, particle density, temperature, and settling‐rate relations described by Stokes' law. In addition, the large bubble volume concentrations released during DAF provided adequate opportunities for collisions between particles and bubbles, thus reducing the need for long flocculation periods. DAF achieved good performance with flocculation periods of 5 min, whereas CGS required at least 20 min of flocculation. In both processes, dissolved organic species and organic halide precursors were removed to the same degree, and similar levels of residual dissolved aluminum were found.
Conservation Legislation
Authors: Pontius Frederick W. , Warburton Albert E.
Published: February 2018

Articles in this section of the Journal are dedicated to providing current information about legislative and regulatory developments. They address needs and concerns of water utilities from a practical standpoint; they are not intended to reflect official positions or policies of AWWA. Frederick W. Pontius, AWWA associate director for regulatory affairs, and Albert E. Warburton, AWWA associate director for legislative affairs, prepared this discussion regarding conservation legislation.
Lessons Learned From the Loma Prieta Earthquake
Authors: Pickett Mark A. , Laverty Gordon L. , Abu‐Yasein Omar A. , Lay Chenwun
Published: February 2018

California's October 1989 earthquake and its effects have been thoroughly analyzed and reviewed by engineers and water utility specialists. Area utility managers interviewed by the authors believe their organizations did fairly well during and after the earthquake, but all suggested improvements that would lessen problems in a future earthquake. In this article the authors review those areas for improvement, including, among many others, internal organization, communication with other public utilities, access to supplies, emergency disinfection, construction methods, and location of distribution lines. The authors suggest that the development and regular testing of an official Emergency Response Plan is crucial if utilities are to perform effectively during the confusing and stressful circumstances of an earthquake or other disaster.
Prevention of Waterborne Cholera in the United States
Authors: Craun Gunther , Swerdlow David , Tauxe Robert , Clark Robert , Fox Kim , Geldreich Edwin , Reasoner Donald , Rice Eugene
Published: February 2018

Since the outbreak of cholera in Peru in January 1991, the disease has spread to other Latin‐American countries and on several occasions has been imported into the United States. In order to assess the risk of transmission of cholera by water in the United States, an ad hoc committee from the Centers for Disease Control (CDC) and the US Environmental Protection Agency (USEPA) prepared a report (on which this article is based) on the etiology of cholera, the history of outbreaks, symptoms and treatment, transmission and survival, analysis of clinical and water specimens, and prevention of epidemics through water treatment and monitoring. The report also describes the steps that have been taken by CDC and USEPA in South America and recommends future action.
Giardiasis Risk From an Unfiltered, Protected Surface Water Source
Authors: Glicker Joseph L. , Edwards Roger A.
Published: February 2018

This article describes the efforts of water utility personnel to determine whether the level of endemic giardiasis observed in their service area could be attributed to the surface water supply, which is chloraminated but not filtered. Comparison of epidemiological data for the county in which the utility is located with data from another county that used conventionally treated water showed similar incidence rates, partitioning into risk categories, and age distributions for giardiasis. There was no correlation between the location of a giardiasis case and disinfection contact time within the unfiltered water's distribution system.
Pilot Study on Treatment of Surface Water for Groundwater Injection
Authors: Nieminski Eva C. , Fenhaus Susan L.
Published: February 2018

A groundwater recharge demonstration project sponsored by the US Bureau of Reclamation is being conducted by the Salt Lake County Water Conservancy District in Utah. Treated surface water will be injected in winter into the aquifer through injection wells and recovered through separate wells during the peak summer months. The conveyance capacity of the project will be 1,000 gpm (5.5 mil L/d). The water will have to meet drinking water criteria before it is injected. To satisfy this requirement, a pilot study, described in this article, was performed from February to June 1990 to determine the best technology for treating the water before injection. Results of jar tests indicated that optimum treatment can be achieved using alum, polymer, and potassium permanganate and that a dual‐media filter outperformed a liquid filter bag. Disinfection with ultraviolet light was selected to be the last treatment prior to injection. On the basis of pilot‐scale testing, a demonstration treatment plant was designed and built. The actual recharge demonstration project will begin in the winter of 1991–92. At the end of this three‐year project, recommendations for a full‐scale project will be made.
Predicting and Verifying Organics Removal by PAC in an Ultrafiltration System
Authors: Adham Samer S. , Snoeyink Vernon L. , Clark Mark M. , Bersillon Jean‐Luc
Published: February 2018

The performance of powdered activated carbon (PAC) in a hollow‐fiber ultrafiltration (UF) system was successfully predicted and measured with respect to the removal of total organic carbon and a representative synthetic organic chemical, 2,4,6‐trichlorophenol, from natural water. Because the adsorption kinetics for smaller PAC particles are much faster than for larger particles, the use of smaller particle sizes allowed the use of shorter PAC contact times. Model predictions for the removal of organic compounds can be used in the design of PAC–UF systems.
Water Audit Encourages Residents to Reduce Consumption
Authors: Nelson John Olaf
Published: February 2018

The North Marin (Calif.) Water District (NMWD) conducted a free home water audit for randomly selected customers from single‐family detached homes. All were in the upper quartile of water use; i.e., residents used about 41 percent more water than was used in the average single‐family home in the service area. At the time of the study, because of publicity about drought in the region, most households had reduced water consumption. For this reason, NMWD used a control group so it could isolate water saved by the audit program. The audit included an interview about patterns of water use, leak identification and repair, installation of low‐flow shower heads and toilet tank displacement devices, evaluation of lawn irrigation practices and recommendation of an irrigation schedule, and distribution of free publications and promotional items. Average annual use declined significantly after the audit, about 16 percent for the sample group and 11 percent for the control group. The difference, or 4.6 percent (9,188 gal), could be attributed to the audit project. Of this amount, 7,270 gal were estimated as being saved inside the home. Only 1,918 gal (less than 21 percent) were calculated as being saved outside the home, far less than NMWD had expected.
How Strategic Is Your Planning?
Authors: Sisson James D.
Published: February 2018

What is the current state of strategic planning in the water utility industry? What types of organizations are most involved in the use of formal strategic planning systems? How is the planning process conducted? How have organizations used the planning process to improve operations? These were the central issues of a strategic planning survey recently conducted among the largest organizations in the water industry to determine how strategic planning has evolved to become an integral part of the management process. This evolution is measured by how long the organization has been planning, how many people are involved in the planning process, how well the strategic plan is communicated to the rest of the organization, and how well strategic planning is linked to other management systems such as budgeting and compensation.
Removing Chlorite by the Addition of Ferrous Iron
Authors: Iatrou Angela , Knocke William R.
Published: February 2018

The application of chlorine dioxide in water treatment has been limited because of concerns about the health effects of residual chlorite (ClO2−) and chlorate. This study investigated the feasibility of using ferrous iron (Fe[II]) to reduce chlorite concentrations. Laboratory tests indicated a required reaction stoichiometry of 3.0‐3.1 mg Fe(II)/mg ClO2−. The reaction rate was rapid for pH values of 5 and greater. Interference from dissolved oxygen was minimal. The ferric hydroxide solids produced as a by‐product of the Fe(II)‐ClO2− reaction had no adverse effect on alum coagulation for the removal of turbidity and dissolved organic carbon.
Developing a Computer Model to Simulate DBP Formation During Water Treatment
Authors: Harrington Gregory W. , Chowdhury Zaid K. , Owen Douglas M.
Published: February 2018

A computer program was developed to simulate disinfection by‐product formation, removal of natural organic matter, inorganic water quality changes, and disinfectant decay in water treatment processes. This article presents equations that simulate the formation of total trihalomethanes (TTHMs), removal of total organic carbon (TOC) and ultraviolet absorbance by alum coagulation, and changes in alkalinity and pH. These equations represent only a small fraction of the entire computer model. Model simulations are compared with limited sets of observed values. The central tendency of the model is to underpredict finished‐water pH by 4 percent, finished‐water TOC by 7 percent, and simulated distribution system TTHMs by 20–30 percent. A discussion of model limitations and research needs concludes the article.
Selecting Particle Counters for Process Monitoring
Authors: Lewis Carrie M. , Hargesheimer Erika E. , Yentsch Clarice M.
Published: February 2018

Instruments that simultaneously count and size individual particles can be used for analyzing raw‐water particulates, optimizing chemical dosages, measuring particulates in filter effluent, determining filter efficiency in terms of percent removal of particles, and many other applications. A single particle counter will not, however, be universally applicable to all of these circumstances. The type of particle counter required will be determined by the types of water samples to be analyzed and the ultimate use of the data. Commercially available particle counters differ in terms of operational principles as well as complexity, particle size range capabilities, concentration limits, resolution, data‐processing power, and physical installation requirements. Basic features of particle counters and a step‐by‐step approach for evaluating particle counter capabilities are discussed, along with installation considerations for water quality monitoring in discrete and on‐line sampling configurations.
Examining Relationships Between Particle Counts and Giardia, Cryptosporidium, and Turbidity
Authors: LeChevallier Mark W. , Norton William D.
Published: February 2018

This study examines concentrations ofGiardiaandCryptosporidium, turbidity, and particles in raw and filtered waters as indicators of treatment plant efficiency. Results indicate that the probability of detecting cysts and oocysts in finished water supplies depends on the number of organisms in the raw water. Particle counts are useful indicators of plant performance and can indicate when filters are not functioning properly.
How Preoxidation Affects Particle Removal During Clarification and Filtration
Authors: Wilczak Andrzej , Howe Elaine W. , Aieta E. Marco , Lee Ramon G.
Published: February 2018

Surface‐water treatment plants are required by the Surface Water Treatment Rule to remove viruses and Giardia lamblia cysts or to inactivate them to specific levels. Particle removal data can be used to demonstrate the level of Giardia removal provided by the treatment system. This article presents the results of particle removal by two clarification‐filtration treatment trains and investigates the effect of preoxidation on process performance. The enhanced removal of particles during filtration, when ozone was used as the preoxidant, was a significant advantage of ozone over chlorine, chlorine dioxide, and potassium permanganate.
Making Automated Systems Successful: How to Win the Hearts of Organizational Skeptics
Authors: Bennett Mary Winter , Myers W. Joseph
Published: February 2018

Too often, organizations implement automated computerized systems from the top down and concentrate on technical issues to the exclusion of human factors. Frequently such systems fail because the people most directly involved with them during the workday find them impractical or resent not having been involved in planning. To prevent this from happening, the authors propose that organizations select from within their ranks a “system champion” who is familiar with the process being automated and who can serve as a focal point for preliminary organization wide communication and for project planning. This article describes the characteristics of such a system champion and the support he or she needs from the organization. It suggests that organizational issues must be addressed as an integral part of systems projects.
Expert Systems Show Promise for Customer Inquiries
Authors: Males Richard M. , Coyle Judith A. , Botchers Harry J. , Hertz Beth G. , Grayman Walter M. , Clark Robert M.
Published: February 2018

This article describes results of an agreement between the North Penn Water Authority in Lansdale, Pa., and the US Environmental Protection Agency, Drinking Water Research Division, Cincinnati, Ohio, to study use of expert systems technology in a water utility. The three‐year study has resulted in the development of computerized expert systems whose basic principles should be broadly applicable to other water utilities. The system described in this article, called a customer query expert system, is designed to assist administrative personnel in handling customers' inquiries and complaints about water quality. The system has been developed as a prototype and will be placed in field operation for further testing and refinement in the near future. Significant effort, however, is expected to be necessary to move from prototype “proof‐of‐concept” demonstrations to fully featured systems that are of practical use in the field.
Voice Mail for the '90s: A Case Study
Authors: Bales Todd Scott
Published: February 2018

The Monterey Division of the California—American Water Company, after assessing the capabilities of its phone system, decided it needed a better way to provide telephone‐related services to its customers. A number of options were examined, and the company chose to lease a voice‐mail system that allows automated notification of on‐call personnel, call routing, and transmittal of messages to a large number of people. Depending on a purveyor's particular needs, voice‐mail systems may allow more control of customer service and emergency response processes at a lower cost than conventional procedures.
Evaluating GAC Adsorbers for the Removal of PCBs and Toxaphene
Authors: Pirbazari Massoud , Badriyha Badri N. , Kim Sung‐Hyun , Miltner Richard J.
Published: February 2018

The research described here investigated the effectiveness of activated carbon adsorption for the removal of polychlorinated biphenyls (PCBs) and toxaphene from organic‐free water (OFW) and humic acid background solution, using bench‐scale equilibrium and rate tests. In addition, complexation experiments were conducted to assess the extent of association between the target pollutants and humic acid (HA). The dispersed‐flow homogeneous surface diffusion model was satisfactory for predicting the performance of fixed‐bed adsorbers for removing PCBs from OFW. When HA was present, carbon capacity was greatly reduced because of complexation and competitive adsorption effects, and the adsorber dynamics were complicated by the presence of various species such as unassociated HA and pollutant–HA complexes.
How Federal Drinking Water Regulations Are Developed
Authors: Pontius Frederick W.
Published: February 2018

Articles in this section of the Journal are dedicated to providing current information about legislative and regulatory developments. They address needs and concerns of water utilities from a practical standpoint; they are not intended to reflect official positions or policies of AWWA. Frederick W. Pontius, AWWA associate director for regulatory affairs, prepared this overview of the regulatory process and coordinates development of future articles.
Presence—Absence Coliform Monitoring Has Statistical Limitations
Authors: Borup M. Brett
Published: February 2018

The new coliform rule promulgated by the US Environmental Protection Agency in 1989 presents a basic and fundamental change in monitoring strategy. The information obtained from this new type of sampling must be handled differently than the density data obtained under the old rule. A statistical analysis of the rule indicates that water of acceptable quality may be found to be in violation of the standard a significant portion of the time and that water of unacceptable quality may be found to meet standards, particularly when small numbers of samples are taken. Monitoring results can be used to estimate the fraction of coliform‐contaminated water and the confidence intervals related to these estimates. Water system conditions that may significantly affect public health violate the assumptions used to develop the standard.
Carbon Regeneration: Dependence on Time and Temperature
Authors: Waer Mark A. , Snoeyink Vernon L. , Mallon Kathryn L.
Published: February 2018

The time and temperature of regeneration were examined in a bench‐scale study using granular activated carbon (GAC) that had been loaded in a treatment plant and a laboratory. Tire rate of regeneration was constant at a given temperature for time periods up to 30 min and increased exponentially with increasing temperature. The reactivity of the base carbon was important in determining the proper time and temperature for regeneration. For coalbased GAC loaded with naturally occurring organic material and methylene blue, GAC capacity was returned to that of virgin carbon at a temperature of 850°C in 15 min. Shorter times and lower temperatures resulted in a loss of adsorption capacity. Longer times resulted in increased capacity for large molecules but the same or reduced capacity for small adsorhates.
Variances and Exemptions for Small Systems
Authors: Pontius Frederick W.
Published: February 2018

The increasing number of drinking water regulations being set by the USEPA and limited financial resources are creating a dilemma for many small water systems. Achieving compliance with the regulations within the time frames specified by the USEPA may not be possible, particularly for small systems. Under certain circumstances, the Safe Drinking Water Act (SDWA) allows water utilities to seek additional time to comply with new regulations by obtaining a variance or an exemption. Variance and exemption criteria are given.
Safe Drinking Water From Small Systems: Treatment Options
Authors: Goodrich James A. , Adams Jeffrey Q. , Lykins Benjamin W. , Clark Robert M.
Published: February 2018

Bringing small water systems into compliance with the ever‐increasing number of regulations will require flexibility in terms of technology application and institutional procedures. This article looks at the means by which small systems can provide safe drinking water, focusing on the advantages, disadvantages, and costs of several treatment options—full‐scale conventional treatment, centrally located package plants, and point‐of‐use or point‐of‐entry devices—for various scenarios.
Evaluating a Commercially Available Defined‐Substrate Test for Recovery of E. coli
Authors: McCarty Shawn C. , Standridge Jon H. , Stasiak Marlyn C.
Published: February 2018

The efficacy of a commercially available defined‐substrate technology (Colilert) was compared with that of a method approved by the US Environmental Protection Agency for enumerating chlorine‐treated Escherichia coli from raw sewage samples. A total of 19 samples was analyzed using a protocol provided by AWWA's Filtration and Microbial Technical Advisory Workgroup. For 18 of the 19 samples analyzed, a greater number of positive tubes was found using the commercially available test. Statistical analysis of the data indicate that this test yielded a significantly higher number of positive tubes for chlorine‐treated coliform bacteria and E. coli when the disinfectant was chloramine. When free chlorine was available during the chlorine treatment, the recovery of E. coli was equal for the two methods.
Creativity, Flexibility Required in Response to Changes in the Workforce
Authors: Elwell Frederick H.
Published: February 2018

Frederick H. Elwell is a vice‐president of Camp Dresser& McKee Inc. and immediate past‐president of AWWA. He became a member of the association in 1969 and has served as chairman and director of the New England Section, chairman of the Water Utility Council, and a trustee of the AWWA Research Foundation. Elwell is a recipient of the George Warren Fuller Award and the 1984 Distinguished Service Award. Earlier this year Elwell was appointed to serve as interim treasurerafter the death of Archie E. Becher Jr.
Water Utilities Prepare for Workforce 2000
Authors: Arthur Sheila Y. , Morgan Voviette D. , Chavez Martín D. , Zeisl Walter S.
Published: February 2018

If they are not already doing so, water utilities need to begin dealing with the cultural diversity that increasingly characterizes the workplace as the twenty‐first century approaches. Ninety utilities, according to a Youth Education Survey released by AWWA in 1990, are already participating in such efforts and have so far reached more than 1.3 million students in grades 1–12. In this article, the authors review programs a few of those utilities have undertaken. Among the options utilities are offering are career education, mentoring, and job shadowing programs, as well as field trips, scholarships, and recruitment. The utilities hope to cultivate a pool of students who will later qualify for permanent employment in the water supply industry.
Proper Meter Sizing for Increased Accountability and Revenue
Authors: Sullivan John P. , Speranza Elisa M.
Published: February 2018

In 1988, the Boston (Mass.) Water and Sewer Commission began investigating the possibility of downsizing meters as a way of reducing unaccounted‐for water. The authors of this article demonstrate that downsizing was successful for a variety of the commission's accounts. As of May 17, 1991, the commission had recovered more than 429,905 gpd of water by downsizing more than 400 meters of size 1.5 in. and larger. In addition to reducing unaccounted‐for water, the downsizing effort could generate more than $2 million annually.
Effects of Background Dissolved Organic Matter on TCE Adsorption by GAC
Authors: Carter Margaret C. , Weber Walter J. , Olmstead Kevin P.
Published: February 2018

The effects of dissolved organic matter, reactor configuration, and granular activated carbon (GAC) particle size on equilibrium adsorption of trichloroethylene (TCE) were examined under simultaneous loading and early preloading conditions. Differences in isotherm capacities obtained using batch‐reactor and column‐reactor estimation methods were observed when natural background organic matter and TCE were adsorbed simultaneously onto nonpreloaded GAC. Differences in isotherms derived from the two methods were diminished, however, when the carbon was first preloaded with the background organic matter in a river water in the absence of TCE. Significant increases in isotherm slope were observed with increasing preloading time for GAC of two different particle sizes. Isotherms determined using powdered activated carbon sieved from crushed preloaded GAC had essentially parallel slopes, however, with capacities greater than the parent preloaded GAC over the concentration range of interest. The observed effects were analyzed in the context of a proposed dualistic model for interpretation of interactions among background organic matter, target solutes, and microporous adsorbents.
Effect of Molecular Oxygen on the Scaleup of GAC Adsorbers
Authors: Vidic Radisav D. , Sorial George A. , Papadimas Spyridon P. , Suidan Makram T. , Speth Thomas F.
Published: February 2018

A rapid small‐scale column test (RSSCT), designed according to the assumption of no dependency of the intraparticle surface diffusion coefficient on the activated carbon particle size, was able to accurately predict breakthrough of three volatile organic chemicals as well as background organic matter under both oxic and anoxic conditions. A second RSSCT, however—designed assuming a linear dependency of the intraparticle surface diffusion coefficient on the activated carbon particle size—significantly overestimated the adsorptive capacity attainable from the large‐column tests. The presence of molecular oxygen in the test environment increased the adsorptive capacity of activated carbon for background organic matter, yielding a delay in its breakthrough from an adsorber. Because of the increased capacity for background organic matter, the resultant capacity for volatile organic chemicals decreased because of competitive effects.
Influencing Regulations Through Litigation
Authors: Rubin Kenneth A. , Pontius Frederick W.
Published: February 2018

Like most federal environmental laws, the Safe Drinking Water Act (SDWA), includes a specific provision that authorizes certain federal courts, at the request of anyone affected by a U.S. Environmental Protection Agency (USEPA) action, to review the validity of such an action. Legal challenges to drinking water regulations assist in achievement of scientifically sound, economically practicable standards. Legal challenges also help prevent implementation of technically unachievable standards. This article explains the judicial review process, describes how organizations like AWWA (as well as individual members) can become involved in this process, and examines the influence of the courts on drinking water regulations.
Seasonal Variations of THMs in Saudi Arabian Drinking Water
Authors: Fayad Nabil M.
Published: February 2018

Samples collected from the distribution systems of eight major cities in Saudi Arabia showed that trihalomethanes (THMs) occurred in all the water supplies. Concentrations ranged between 0.03 and 41.7 μg/L, much lower than the 25O‐μg/L limit set by the Saudi Arabian Standards Organization. Median total THM concentrations in the cities of Riyadh, Jeddah, Madinah, Makkah, and Abha were higher during the summer than in the winter. In addition, THM concentrations were low in cities that did not mix groundwater and desalinated water. Brominated THMs dominated (with bromoform the most abundant) and existed at the highest concentration levels, whereas chloroform was the least prevalent compound. This is the opposite of the occurrence pattern found in almost all water distribution systems worldwide.
Effect of Bromide Ion on Formation of HAAs During Chlorination
Authors: Pourmoghaddas Hossein , Stevens Alan A. , Kinman Riley N. , Dressman Ronald C. , Moore Leown A. , Ireland John C.
Published: February 2018

A two‐block full‐factorial matrix was designed to statistically evaluate the influenee of bromide ion on the formation and speciation of haloacetic acids (HAAs) during chlorination and the effects of independent variables, including pH, reaction time, and chlorine dosage. Almost all of the independent variables were positively correlated with the formation of HAAs. Bromide ion was shown to shift the distribution of HAAs (as well as trihalomethanes) to more brominated species. Not only were purely brominated acetic acids formed, but also mixed bromine and chlorine species—which were measured for the first time.
Monitoring and Control Experience Under the Lead and Copper Rule
Authors: Ramaley Brian L.
Published: February 2018

Monitoring requirements under the Lead and Copper Rule took effect in 1992 for large and medium‐size public water suppliers and will take effect in 1993 for small systems. Starting in the mid‐1980s, the Newport News Waterworks began planning for compliance with lower tap water limits for lead and copper. A lead service line replacement program has been completed, corrosion inhibition treatment through the use of zinc orthophosphate has been optimized to limit lead, and at‐the‐tap monitoring has been in place since 1988. Results obtained from Lead and Copper Rule compliance monitoring indicate these efforts have contributed to compliance with the action levels for lead and copper under the rule and have reduced lead levels at customers' taps.
D–DBP Regulation: Issues and Ramifications
Authors: III Edward G. Means , Krasner Stuart W.
Published: February 2018

This article gives an overview of the process and events that have shaped the current debate over the regulation of disinfectants and disinfection by‐products (D‐DBPs) in the United States. Particular emphasis is placed on the technical uncertainties that complicate the establishment of health‐protective maximum contaminant levels for several disinfectants and their by‐products. In addition to a discussion of recent developments in the DBP arena, a retrospective of D‐DBP rule‐making history is provided.
Optimizing Chloramine Disinfection for the Control of Nitrification
Authors: Lieu Nancy I. , Wolfe Roy L. , III Edward G. Means
Published: February 2018

Previous studies have shown that nitrification of chloraminated drinking water can have deleterious effects on water quality. These studies also showed that the cause of nitrification is the oxidation of ammonia (used to form chloramines) to nitrite by autochthonous nitrifying bacteria. In this study, bench‐scale experiments were conducted with fully treated drinking water to determine the optimum chloramine application conditions necessary to prevent nitrification in the distribution system. These experiments examined the survival and regrowth of nitrifying bacteria after exposure to three chloramine dosages, three weight ratios of chlorine to ammonia‐nitrogen, three temperatures, and two contact times. The results indicate that the control of ammonia‐oxidizing bacteria is highly dependent on temperature.
Discussion: Pilot Testing a Limestone Contactor in British Columbia
Authors: Letterman Raymond D.
Published: February 2018

The May 1992 issue of the Journal contained an interesting and useful article by Benjamin et al on the pilot testing of limestone contactors in British Columbia, Canada. This discussion examines one of the conclusions of that article and reports on the availability of a limestone contactor design program (DESCON) that was recently prepared with support from the US Environmental Protection Agency.
SDWA: Speculating on the Future
Authors: Hei Diane VanDe
Published: February 2018

Speculating on what is likely to occur with reauthorization of the Safe Drinking Water Act (SDWA) before the debate begins in the 103rd session of Congress is risky at best. But in order to prepare for this debate, an analysis of the likelihood of congressional action and a discussion of some of the issues that have come to the forefront are presented.
Removing Nitrate With a Methylotrophic Fluidized Bed: Technology and Operating Performance
Authors: Liessens Jan , Germonpré Richard , Beernaert Stan , Verstraete Willy
Published: February 2018

A pilot biological fluidized‐bed plant with a capacity of 40 m3/h has been in operation since January 1988 at De Blankaart drinking water production center for removing nitrate from surface water. Methanol is used as the reductant. With a nitrate removal efficiency of 9.0 kg NO3−/m3 reactor.day at 3.5°C, the system has shown superior performance compared with conventional fixed‐bed biofilm reactors. With an influent concentration of 75 mg NO3−/L, complete nitrate removal was achieved at an empty bed contact time of 15 min. Nitrite was not detected in the effluent, provided there was a slight excess of methanol (1–2 mg/L). Residual methanol was easily removed by the existing downstream drinking water treatment processes.
Investigation of the Regent Street Water Tower Collapse
Authors: Dawe John L. , Seah C.K. , Abdel‐Zaher A.K.
Published: February 2018

The newly constructed Regent Street water tower in Fredericton, N.B., Canada, totally collapsed Dec. 19, 1990, during the normal procedure of initial filling. Many samples of materials were taken from the wreckage for testing. All available design documentation and the construction process were thoroughly reviewed in an effort to determine the cause of the catastrophic collapse. In particular, the design of the steel water‐storage cell was conducted retroactively for six sets of practical design specifications in use in North America and Europe. Additionally, extensive computerized numerical modeling was employed to study the complex stresses and buckling characteristics of the storage cell. A thorough investigation revealed that the collapse of the Regent Street water tower occurred primarily as the result of a deficient thickness of the lower conical portion of the storage cell. Other factors that may have contributed to the final collapse are discussed, but the extent of their contribution is a complex and largely unquantifiable question.
Testing Biologically Active Filters for Removing Aldehydes Formed During Ozonation
Authors: Kramer Stuart W. , Sclimenti Michael J. , Coffey Bradley M.
Published: February 2018

This pilot‐plant study was initiated to evaluate biological filtration for the removal of aldehydes formed during ozonation. An additional objective of this testing was to demonstrate that aldehyde measurements could be used as a surrogate for analysis of assimilable organic carbon (AOC). The use of granular activated carbon (GAC) as an alternative to anthracite coal as the filter medium was also investigated, and it was observed that GAC filters developed biological activity sooner and showed longer‐term stability. Although biological activity was established sooner on slow‐rate filters, the high‐rate filters in time achieved a comparable capability. Data for formaldehyde and glyoxal provide information on removal of readily biodegradable and more recalcitrant ozone by‐products, respectively, and demonstrate trends similar to those for the removal of AOC.
Testing Reinforced Concrete Structures for Watertightnes
Authors:   American Concrete Institute–AWWA Committee Report
Published: February 2018

The American Concrete Institute Committee 350, Environmental Engineering Concrete Structures, recognized a need for standardized criteria as well as a standardized method of testing reinforced concrete structures for watertightness. AWWA's Committee 400, Waterproofing, was also interested in documenting the state‐of‐the‐art of watertightness testing and criteria for reinforced concrete tanks. A joint subcommittee was subsequently formed to prepare a report containing recommendations on watertightness for reinforced concrete containment structures. This article presents the findings of the joint report.
Tapping USEPA's Integrated Risk Information System
Authors: Pontius Frederick W.
Published: February 2018

The integrated risk information system (IRIS) is a U.S. Environmental Protection Agency database that contains the agency's consensus positions on the potential human health effects of approximately 500 substances. It was created in 1986 for use by agency staff and was made available to the public in 1988. When consensus is reached within the agency regarding the health risk of a substance, that information is made available in IRIS.
How Will Small Water Systems Finance SDWA Compliance?
Authors: Teernstra Bonny
Published: February 2018

Many public water systems are faced with having to invest in plant and equipment to monitor and treat their drinking water in order to comply with the Safe Drinking Water Act. For small systems, financing these expenditures will likely be difficult. This article reviews the options available for the small water system to obtain funds for capital expenditures and outlines the criteria that the utility is expected to meet before it can be considered for a loan. The author emphasizes that demonstration of financial stability is a primary requirement. The risk of lending money to small water systems is evaluated. Assistance that may be provided by public agencies is also addressed.
Ion Exchange: A Cost‐Effective Alternative for Reducing Radium
Authors: McKelvey Gregory A. , Thompson Mark A. , Parrotta Marc J.
Published: February 2018

The first project under the US Environmental Protection Agency's small systems technology initiative, which was designed to generate simpler treatment technologies for small systems, has been completed. At Quail Creek, located about 60 mi northwest of Austin, Texas, ion exchange was used to reduce radium concentrations in the well water. Although the project was successful, the authors caution that this technology may not be universally applicable to small systems because of certain site‐specific advantages held by this system.