bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors that affect use of direct filtration in treating surface waters
Authors: McCormick Richard Ford , King Paul H.
Published: February 2018

This paper evaluates direct filtration as a treatment method for water from five sources in Virginia. The most effective filtration scheme consisted of a three‐minute rapid mix with alum and a cationic polymer used in combination as primary coagulants. The rapid mix was followed by filtration at 3.5 mm/s (5 gpm/sq ft) through 51 cm (20 in.) of 1.3‐mm effective size (e.s.) anthracite coal and 25 cm (10 in.) of 0.45‐mm e.s. silica sand. This configuration produced filtered water that met the AWWA goal for turbidity with filter run times of at least eight hours when color and turbidity in the raw water were less than 15–20 units.
The effect of backwashing rate on filter performance
Authors: Qureshi Naeem
Published: February 2018

In a series of plant‐scale investigations, two identical filters were subjected to fluidization and subfluidization backwashing rates. A higher initial degradation of the effluent turbidity was observed for filters in which subfluidization conditions prevailed. The head loss was higher for filters back washed at a lower rate resulting in shorter filter runs. The study confirmed the existence of two peaks during the degradation of filter effluent quality during the initial part of the filter run. Mudball formations did not occur during backwashing at subfluidization velocities. Lower backwashing rates have economic advantages.
The regulatory climate and the water utility manager
Authors: Buescher Charles A.
Published: February 2018

This article advocates greater involvement by the water utility industry in two major areas of water quality and monitoring. Detailed water analyses should be available to customers on an annual basis, which may mean expanded monitoring on the part of the utility for normal characteristics as well as for trace organics and manmade contaminants. In addition, the responsibility for research on health effects and treatment concepts should rest with the industry rather than with agencies of the federal government.
How rate structures and elasticities affect water consumption
Authors: Comer Dorothy , Beilock Richard
Published: February 2018

Projections of the influence of single rate structures, declining rate structures, and inclining rate structures on water consumption depend on varying assumptions about how consumer demand will relate to the cost of water.
East is West and West is West: Have the twain met?
Authors: Cahill Thomas E.
Published: February 2018

States whose water use laws are based on the riparian doctrine are increasingly aware of the limitations of this ancient common law. These states should consider some of the advantages of the prior appropriation doctrines used in the semiarid West.
Treatment of drinking water containing trichloroethylene and related industrial solvents
Authors: Love O. Thomas , Eilers Richard G.
Published: February 2018

Laboratory and pilot‐scale studies have been carried out to ascertain the effects of aeration, adsorption, and boiling on water containing volatile organic solvents. These treatment methods are discussed, estimates of treatment costs are made, and data on the characteristics of the following compounds are given: trichloroethylene, tetrachloroethylene, 1,1,1‐trichloroethane, cis‐1,2‐dichloroethylene, carbon tetrachloride, and 1,2‐dichloroethane.
Direct filtration and removal of THM precursors
Authors: White George Clifford
Published: February 2018

Writing in response to the theme articles on “Improving Filtration Techniques” (JOURNAL AWWA May 1982), this reader points out the lack of available information on the efficiency of direct filtration on the removal of THM precursors. The reader also requests that more data on this subject be made available through the JOURNAL, along with information on alternative techniques such as the use of sedimentation after proper coagulation.
Forecasting short‐term revenues for water and sewer utilities
Authors: Boland John J. , Wentworth Roland W. , Steiner Roland C.
Published: February 2018

Since water use depends on variables such as temperature and precipitation, projected short‐term water and sewer revenues can be seriously affected by weather. A computerized model was developed for the Washington Suburban Sanitary Commission (WSSC) to incorporate the statistical probability of the occurrence of identified variables and their influence on water use and therefore on water revenues. The model is used to provide a 24‐month forecast of short‐term revenues for WSSC.
Technical note: Removing trihalomethane formation potential by coagulation with activated silica and cationic polymer
Authors: Batchelor Bill , Yang Pe‐der
Published: February 2018

This paper presents the results of jar test experiments that show the ability of activated silica and a cationic polymer to remove trihalomethane formation potential when used as the sole coagulant or in conjunction with alum. A possible mechanism to explain the results is discussed.
Groundwater quality management
Authors: Canter Larry W.
Published: February 2018

Groundwater quality management requires knowledge of the quantitative features of aquifers, present and anticipated demands for water usage from aquifers, natural sources of groundwater pollution, manmade sources of actual or potential groundwater pollution, modeling to determine the influence of water usage and pollution sources on available water quantity and quality, and institutional arrangements for regulation and control.
Detecting an algal toxin by high‐pressure liquid chromatography
Authors: Wong See Hoi , Hindin Ervin
Published: February 2018

A high‐pressure liquid chromatographic method is proposed for isolating and quantifying aqueous solutions of anatoxin‐a, a neurotoxin produced by certain strains of Anabaena flos‐aquae. A normal phase Silica‐A column with an 80 percent solution of isopropanol in hexane or a C18 reverse phase column with an 80 percent aqueous solution of acetonitrile gave good separation. Ultraviolet spectrophotometric detection at 227 nm provided for optimum quantification.
Measuring chlorine dioxide with a rotating voltammetric membrane electrode
Authors: Smart R.B. , Freese J.W.
Published: February 2018

A new rotating voltammetric membrane electrode has been developed and used to measure chlorine dioxide in water and wastewater. It is capable of detecting low concentrations (<1 mg/L) of chlorine dioxide and is suitable for continuous, automated monitoring. At a chlorine dioxide concentration of 0.30 mg/L, the relative standard deviation is 6.4 percent. This electrode has been compared with the chlorophenol red and iodometric methods for measuring chlorine dioxide.
Designing and installing large steel water mains to prevent failures
Authors: Fletcher Stanley T.
Published: February 2018

The first section of this article addresses the precautions that can be taken in the design and installation of large‐diameter steel conduits to prevent failures. The second section describes a massive failure of an 1800‐mm (72‐in.) pipeline, the resulting investigation to determine the cause of the failure, and the legal settlement of damages.
Organizing and analyzing leak and break data for making main replacement decisions
Authors: O'Day D. Kelly
Published: February 2018

Water main replacement decisions may be based on arbitrary criteria such as age or on historic operating records and the experiences of a utility. Use of the latter method enables a utility to analyze leak and break patterns and to develop rehabilitation‐replacement plans. The author provides an overview of the causes of water main breaks and leaks and then describes several studies in which water main breaks have been analyzed in terms of pipe age, geographic location, or diameter.
A model of costs for treating drinking water
Authors: Clark Robert M. , Dorsey Paul
Published: February 2018

The Safe Drinking Water Act of 1974 emphasizes the need to consider costs when promulgating regulations. In response to the concerns about the costs of technological requirements, research was undertaken to develop cost data associated with 99 unit processes for treating drinking water. These estimates were used as a basis for regression analysis estimates calculated on equations that were derived for operations and maintenance costs and capital costs annualized at 8 percent over a 20‐year amortization period. The equations and some typical applications are presented.
Drinking water and Legionnaires' Disease
Authors: Dufour Alfred P. , Jakubowski Walter
Published: February 2018

The elusive bacterium that causes legionellosis apparently thrives in some water distribution systems in buildings. This respiratory disease has not been associated with ingestion of drinking water but seems to occur with secondary water use when bacteria are inhaled in aerosol form from sources such as showerheads. This article discusses up‐to‐date information on control measures, the various forms of the disease, and methods of detecting the presence of the bacteria.
Viewpoint – The Cure for Stress: A Sense of Humor
Authors: Brigham Arthur P.
Published: February 2018

The author of this article, Arthur P. Brigham, shares personal experiences from 22 years of working as a water utility public relations manager. The author proposes that stress can be alleviated by a sense of humor, stating that “if you're a water utility manager or staff person who thinks stress is getting to you, start now to look for the bright and funny side of every happening. I did, and I developed a reservoir of memories to draw on to repel stress and tension.” He then goes on to relay many of those memories in this humor filled article.
Principles of internal corrosion and corrosion monitoring
Authors: Kirmeyer Gregory J. , Logsdon Gary S.
Published: February 2018

Corrosion is a complex electrochemical phenomenon that cannot always be eliminated but can usually be controlled in a cost‐effective manner. Corrosion may be uniform and attack a surface evenly or may cause severe localized problems, such as a crevice or pit. For the corrosion reaction to proceed, all components of an electrochemical cell—an anode, a cathode, a connection between the anode and cathode, and a conducting solution—are required. Methods for documenting corrosion range from simple visual inspections to complex scale analyses. Laboratory and pilot tests can be used to define the extent and magnitude of corrosion. Corrosion control programs should be developed with a two‐phased approach in mind: changing water chemistry and using corrosion‐resistant materials. Monitoring is important to ensure that the corrosion control program continues to meet its desired objective.
Desalting—a water supply alternative for Virginia Beach
Authors: Robinson Millard P. , Westerhoff Garret P. , Leahy Thomas M.
Published: February 2018

Fundamental technical and economic issues related to large‐scale reverse osmosis desalting facilities are discussed. When conventional water supply sources are scarce, developing sources that require dissolved‐solids removal is increasingly attractive as improvements are made in commercially available membrane devices.
Formation of organic chlorine in public water supplies
Authors: Fleischacker Stephen J. , Randtke Stephen J.
Published: February 2018

The formation of purgeable and nonpurgeable organic chlorine was evaluated as a function of the type and concentration of precursor material, the type and dosage of chlorine, pH, temperature, and ammonia concentration. The concentration of organic chlorine in a public water supply can be minimized by avoiding prechlorination, avoiding higher concentrations of chlorine than are necessary for good disinfection, using combined chlorine rather than free chlorine, maintaining a high pH, and withdrawing water from a source with a low concentration of precursor material and a cool temperature. Because the conditions that favor lower concentrations of organic chlorine are generally the same conditions that tend to reduce the efficiency of disinfection, careful consideration must be given to the adequacy of disinfection if efforts are made to reduce organic chlorine formation.
Evaluating the economics of alternative technology for small water systems
Authors: Deb Arun K. , Richards William G.
Published: February 2018

The WATer MANagement model (WATMAN) was expanded for application to small water systems serving populations of 100–10 000 so that the economics of alternative solutions to meeting new water quality standards can be evaluated. Two hypothetical cases and two actual situations were tested with the model to select preferred water supply options.
Discussion of tetrachloroethylene in drinking water: a toxicologist's perspective
Authors: Calabrese Edward J.
Published: February 2018

This discussion addresses questions of possible mutagenicity, carcinogenicity, and teratogenicity relative to exposure to tetrachloroethylene (PCE) in drinking water. The author highlights results of mutagenicity, carcinogenicity, and teratogenicity studies of PCE. Results of these studies indicated that there is no convincing evidence that PCE is a mutagen or teratogen. Carcinogenicity studies indicate that a lifetime exposure of 9 to 35 ppb PCE would increase the risk of cancer by 1 in 100,000 persons. However, the accuracy of this prediction is not verifiable.
Enterovirus removal by a full‐scale tertiary treatment plant
Authors: Leong Lawrence Y.C. , Argo David G. , Trussell R. Rhodes
Published: February 2018

A four‐year study in which enteroviruses were monitored at a 56‐ML/d (15‐mgd) advanced wastewater treatment plant is summarized. The process train included high pH‐lime treatment, air stripping, recarbonation, prechlorination, multimedia filtration, granular activated carbon adsorption, reverse osmosis demineralization, and final chlorination. The influent and effluent were sampled on the average of once per week. During this study, viruses were detected twice in chlorinated effluent at very low levels and were associated with operational problems of the final disinfection process. Subsequent dilution by blending and injection of the final effluent into a groundwater aquifer, which resulted in additional dilution and treatment, has produced a water that is essentially free of enteroviruses.
Removing nonvolatile organic chlorine and its precursors by coagulation and softening
Authors: Johnson Douglas E. , Randtke Stephen J.
Published: February 2018

Samples of groundwater, surface water, secondary effluent, and fulvic acid were treated in laboratory experiments by alum coagulation and lime softening in conjunction with prechlorination and postchlorination. Coagulation and softening both removed significant amounts of nonvolatile organic chlorine, precursors of organic chlorine, and total organic carbon (TOC). Organic chlorine precursors were removed as well as or better than TOC and much better than the organic chlorine formed during prechlorination. The increase in pH during lime treatment hydrolyzed a significant fraction of the nonvolatile organic chlorine, releasing chloroform and other by‐products.
Using backwashing kinetics to evaluate attachment mechanisms and forces during filtration
Authors: Toregas George
Published: February 2018

A method is offered for evaluating the various modes involved in particle removal from water by means of deep‐bed filtration. Based on backwashing kinetics, this method takes into account the mechanisms associated with particle attachment (with and without alum treatment), particle agglomeration, and particle detachment.
The chemistry of reduced sulfur species and their removal from groundwater supplies
Authors: Dohnalek David A. , FitzPatrick Joseph A.
Published: February 2018

The removal of hydrogen sulfide from groundwater supplies was investigated by using various catalysts and oxidants in bench‐scale jar tests that simulated assumed actual conditions in a water treatment plant. Variations in aeration rate, chemical dosage, recycled solids, pH, and detention time were also examined. A ferrous sulfate dosage of 9 mg/L reduced sulfide concentrations to 0.05 mg/L, largely owing to the catalytic effect of Fe(II). Peroxide, permanganate, and ferrate also lowered the sulfide concentrations, with more rapid kinetics than Fe(II). An economic analysis showed that Fe(II) is a cost‐effective alternative for sulfide removal. The other oxidants may also prove economical under certain conditions.
Privatization Panned
Authors: Foster Bill
Published: February 2018

This reader writes to disagree with the way Steve Hanke in “Face to Face” (JOURNAL AWWA May 1983) viewed municipally owned utilities. Hanke portrayed privately owned utilities as superior to publicly owned ones. This reader sites examples of successfully operated public water utilities.
Denver's water conservation program
Authors: Wiley R.D.
Published: February 2018

The most obvious means of conserving water throughout the Denver Water Department's service area is to curb the thirst of homeowners' bluegrass lawns, which consume 80 percent of the residential water used during the summer months. In response to water shortages and a court decree, the water department has undertaken a variety of programs to restrict water use during the growing season and to develop a conservation ethic among customers without imposing unreasonable lifestyle changes.
Reducing water demand and wastewater flow
Authors: Maddaus William O. , Parker Denny S. , Hunt Alfred J.
Published: February 2018

This study shows that inside residential water use and wastewater flow could be reduced by about 10 percent if low‐flush toilets, low‐flow showerheads, and low‐flow lavatory faucets were installed throughout the Dublin, San Ramon, and Pleasanton areas of California. Such fixtures are now required for new construction in California. Retrofitting existing homes could be accomplished with an aggressive program to make older homes more water efficient and would be less costly than expanding the capacity of the wastewater disposal system.
Wastewater reuse: a resource or a nuisance?
Authors: DeBoer Jon G.
Published: February 2018

As demand for good quality water increases, some areas in the United States find that traditional finite sources cannot meet all needs. Although many utilities draw potable supplies from water that has previously been used upstream, the direct reuse of treated water for potable supplies is limited by unknowns concerning health effects and by costs. Planned reuse options, however, are feasible water conservation techniques, especially for industrial and agricultural uses. Reclaimed wastewater can also be used to recharge groundwater, thereby augmenting potable supplies.
The design of in‐line jet injection blenders
Authors: Güven Oktay , Benefield Larry
Published: February 2018

Available information on the initial mixing characteristics of turbulent jets in crossing pipe flow is reviewed, and criteria for the optimum design of in‐line jet injection blenders are described. A previously proposed design procedure for centrally injected jets is discussed, and an analysis is presented to indicate how this procedure can be improved.
Environmental studies of enteric bacteria longevity in membrane filter chambers
Authors: Dutka B.J. , Kwan K.K.
Published: February 2018

Two studies were carried out over several seasons to ascertain the survival of pathogenic, indicator, and tracer bacteria in membrane filter chambers. The survival times for these bacteria were lengthy (≥77 days) under either summer or winter conditions. Thus, the use of seasonal effluent disinfection might eventually result in bacterial contamination of downstream sediments and possibly of waters overlying these sediments. As a result of certain disturbances, these bacteria could be recycled throughout the water column and eventually into man or animals directly or indirectly through potable water supplies.
Granular activated carbon installations
Authors: Culp Russell L. , Clark Robert M.
Published: February 2018

This article presents a compilation and summary of design criteria, performance, and cost data from 22 operating municipal and industrial granular activated carbon (GAC) installations that treat water and wastewater or process food and beverage products. Guidance for using this information to estimate costs for GAC treatment of water supplies is provided. In conjunction with previous reports, this article may be used to obtain project‐specific cost estimates for water treatment. Although this article does not provide design criteria such as required contact time, probable regeneration frequency, activated carbon reactivation system criteria, or activated carbon transfer guidelines, it presents an approach to determining such design data for water systems.
Evaluating GAC adsorptive capacity
Authors: Randtke Stephen J. , Snoeyink Vernon L.
Published: February 2018

Potential sources of error in evaluating the adsorptive capacity of granular activated carbon (GAC) are identified and discussed, with special attention given to carbon sampling and preparation, preparation of test solutions, and selection of GAC dosages, adsorbate concentration, and equilibration time. Adsorptive capacity can vary with particle size, but data are presented to show that this may not always occur. Heterogeneous solutions require careful selection of GAC dosages and adsorbate concentration, and the data for such solutions require careful interpretation. Model simulations are used to illustrate the importance of closely approaching equilibrium and to estimate the time required to approach equilibrium under various conditions. For large GAC particles and slowly diffusing adsorbates, several years may be required to reach equilibrium. Failure to reach equilibrium can result in a significant underestimation of adsorptive capacity. Pulverizing GAC greatly reduces the time required to reach equilibrium, thus reducing the possibility of biodegradation of the adsorbate.
Adsorption of chlorinated methanes from aqueous solution on selected plastic adsorbents
Authors: Cook Freeman C. , Hartz Kenneth E.
Published: February 2018

Batch adsorption experiments were conducted by using polyethylene, neoprene, polyvinyl chloride, and polyurethane foam as adsorbent materials. Granular activated carbon was included in the study for the purpose of comparison. The organic compounds used were members of a homologous series that consisted of methylene chloride, chloroform, and carbon tetrachloride. Adsorption tests were conducted at three solution concentrations: 0.1, 1.0, and 10.0 mg/L. The adsorptive capacity of each material was evaluated by using both the Freundlich and the Langmuir adsorption models. The results of this investigation indicate that plastic adsorbent materials may be used to remove selected chlorinated organics from aqueous solution with varying degrees of effectiveness.
Effects of prechlorination on THM formation and microbial growth in pilot‐plant units
Authors: Reed Gregory D.
Published: February 2018

Prechlorination with chloramine (unit 1) and prechlorination with free chlorine (unit 2) were equally effective in removing and controlling trihalomethane (THM) precursors in parallel pilot systems that varied only in the method of prechlorination. As expected, the THM levels in unit 1 were low and those in unit 2 were high. Control of the bacterial population (as determined by standard plate count) in unit 1 was more consistent than that in unit 2.
The analysis of organohalides in water—an evaluation update
Authors: Dressman Ronald C. , Stevens Alan A.
Published: February 2018

Data acquired during the routine use of an organic halide analyzer are presented. These data were used for judging the quality of measurements of total, purgeable, and nonpurgeable organic halides as well as for judging the instrument's dependability and ease of operation.
Viewpoint – Calming Troubled Waters Through Regulatory Reform
Authors: Mellendorf Loren D.
Published: February 2018

In this month's “Viewpoint,” the author discusses the need for regulatory bodies to develop new ideas and procedures for regulating the production of potable water that would assist utilities in providing water to customers at fair prices. Also discussed is the need to better educate the public concerning the true costs of treating and delivering potable water. Without this public relations effort, the public will not support rate increases which are inevitable.
Strategic financial planning
Authors: Nolan Robert B. , Foran Robert E.
Published: February 2018

Water utilities cannot rely on traditional methods of financing debt for capital projects in today's volatile financial markets. Capital improvement plans should incorporate the flexibility needed to take advantage of opportunities in changing markets, thus allowing publicly owned water utilities to maximize their financial resources.
Indexing water rates
Authors: Adams Arthur H. , Vogler Gregory J.
Published: February 2018

Indexing would allow water rates to move up or down in response to changes in the cost of providing service. Although indexing techniques have not been applied to water rates, they are used in the electric utility industry and could provide a method of generating adequate water revenues, particularly during periods of inflation.
Effects of holding time and temperature on conform numbers in drinking water
Authors: McDaniels Audrey E. , Bordner Robert H.
Published: February 2018

Concern has often been expressed about the reliability of coliform counts from drinking water samples held in transit before analysis. Samples collected from a municipal distribution system were split, stored at ambient (22°C) and refrigerator (5°C) temperatures, and analyzed over time for total coliform and heterotrophic bacterial densities. Coliform populations declined significantly at both temperatures after 24 hours. The rate of decline was 2.5 orders of magnitude greater at 22°C than at 5°C. Average losses in 24 hours were 34 percent at 5°C and 87 percent at 22°C. Growth and interference of heterotrophic bacteria with coliform colonies on membrane filter plates were frequently observed for samples held at ambient temperature for 30 hours. A model based on actual coliform recovery was developed to predict initial coliform counts in samples held at various times before examination. For the waters examined, samples held at 22°C for 30 hours with initial coliform counts as high as 100/100 mL could have been reported as satisfactory, thus resulting in inaccurate and misleading information.
Methods for testing the efficacy of ultraviolet light disinfection devices for drinking water
Authors: Tobin R.S. , Smith D.K. , Horton A. , Armstrong V.C.
Published: February 2018

Ultraviolet (UV) light devices have been used in the disinfection of raw drinking water at the point of use, but the need for reliable fail‐safe devices has been demonstrated. A study was performed to establish test protocols that could be used to ensure adequate disinfection under adverse conditions, particularly in the presence of turbidity and color in the water. A test protocol was devised for fail‐safe light sensors by using a color or turbidity agent in the feed solution to reduce the UV dosage to the established minimum limit, 16 000 μW·s·cm‐2, in order to determine whether the fail‐safe device was properly calibrated and functional. Three commercial UV devices were tested with this method; one device was satisfactory, the second unit was set too low by a factor of 1.6, and the third unit was set too low by a factor greater than 2.
Axial and bending behavior of pipeline joints
Authors: Singhal A.C. , Benavides J.C.
Published: February 2018

Pipeline joints (ductile‐iron pipes with push‐on rubber gaskets) of various diameters (100 mm [4 in.], 150 mm [6 in.], 200 mm [8 in.], and 250 mm [10 in.]) were tested to determine their structural behavior when subjected to static loading and reloading conditions. Pull‐out and bending tests were performed on joints under buried, semiburied, and unburied conditions. The linear and nonlinear behavior of the joints was observed, including large joint displacements and joint slippage. Graphs of the pull‐out force versus joint displacement and of bending moment versus joint rotation were drawn based on test data. Analysis of the data on pull‐out tests showed a common pattern, as did that on bending tests.
Keeping Old Reservoirs Active
Authors: Whitfield Fred
Published: February 2018

Experience in Portland, Ore., with old open storage reservoirs as well as a variety of covered storage facilities has evolved into a routine cleaning, maintenance, and protective program. Storage of chlorinated water in the open reservoirs in Portland's system requires periodic cleaning to prevent water quality deterioration, and protection of these reservoirs from the public is also important. The Portland Water Board has significantly extended the useful life of the aging facilities with these procedures.
Construction Arbitration and Mediation
Authors: Hoellering Michael F.
Published: February 2018

Resolving construction disputes through means other than litigation is now recognized throughout the construction industry as a more expeditious, less costly, and less timeconsuming means of settlement. Arbitrators and mediators are professionals who are knowledgeable about construction practices, are trained by the American Arbitration Association, and are neutral. Parties to the dispute are assured that arbitrators or mediators understand the complexities of construction disagreements and can resolve the issues equitably.
Matching Graphics With Subject Matter
Authors: Murphy John B.
Published: February 2018

John B. Murphy, writing in response to an article by Lackowitz and Petretti, “Improving Energy Efficiency Through Computer Modeling” (Journal AWWA October 1983), noted that the photographs used had no relevance to the subject matter of the article and were entirely misleading. The editors of the Journal agreed that the photographs had been supplied from sources other than the authors.
Current Research on the Effects of Acid Deposition
Authors: Perry James A.
Published: February 2018

Preliminary research aimed at quantifying relationships between emissions and acid deposition and on‐the‐ground effects indicates that small water supplies fed by surface waters or shallow wells and cistern supplies may be adversely affected by acid deposition. In addition, acid deposition makes water more corrosive, which may result in dangerous quantities of heavy metals in distribution systems. This will not be a problem with relatively hard water or with relatively large supplies, and corrosivity should be treatable at reasonable cost.
Developing Joint Water Projects
Authors: Hardten Ronald D.
Published: February 2018

Water purveyors that serve large cities in the United States are often faced with providing service to rapidly growing areas outside the city limits. In many cases, joint development of water supplies, treatment facilities, and distribution systems allows all the agencies to take advantage of the financing capacity of the larger entity, provides economy‐of‐scale, and avoids some of the deleterious effects of population shifts from central cities to outlying areas.
Spectrophotometric Determination of Total Trihalomethanes in Finished Waters
Authors: Huang Jerry Y.C. , Smith Gary C.
Published: February 2018

Research into a spectrophotometric method for measuring total trihalomethanes in drinking water is described. The procedure is based on the classic Fujiwara reaction, which is characterized by the red color that develops when a halogen compound is heated with sodium hydroxide and pyridine. Although less sensitive and less specific than gas chromatography, this method is relatively simple and inexpensive and could be used in water treatment plant laboratories to screen for total trihalomethanes in finished waters.
Pump Station Design: The Benefits of Computer Modeling
Authors: Robinson Millard P. , Blair R. Edwin
Published: February 2018

Selecting the best design for new distribution pumping stations is difficult without the aid of mathematical computer models. Several analyses of the Norfolk (Va.) water system were performed to determine pump characteristics at various demand conditions, system head curves, pump combinations, control valve‐sizing, and back‐pressure control settings.
Lower Detection Limits Found for Chlorine Dioxide Contaminants
Authors: Gordon Gilbert , Ikeda Yasuhisa
Published: February 2018

Disinfecting water with chlorine dioxide eliminates trihalomethane formation but generates several contaminants of its own. Government regulations under consideration would require the removal of these by‐products to levels for which no detection methods have existed. Chemists at the Miami University of Ohio have developed a method to measure chlorate, chlorite, and hypochlorite ions at levels of less than 1 mg/L. The detection accuracy range is ±3 percent.
Conditions Contributing to Underground Copper Corrosion
Authors: Myers James R. , Cohen Arthur
Published: February 2018

Copper, a noble metal that occurs naturally in its elemental form, is almost totally impervious to corrosion from soils found worldwide. But it would be misleading to infer that copper will not corrode. This article identifies a host of possible situations in which copper pipe or tubing may be subject to external corrosion. These situations are discussed in detail, and suggestions are given on how to identify underground corrosion of copper pipe without excavating and how to mitigate existing corrosion conditions.
Temperature and Ionic Strength Corrections to the Langelier Index—Revisited
Authors: Schock Michael R.
Published: February 2018

The saturation state of calcium carbonate in water has been determined for years by use of the Langelier Index. The US Environmental Protection Agency today specifies its use by water suppliers. Yet the 40‐year‐old chemistry that fostered popular, simplified versions of the index has undergone substantial evolution. Some chemists believe correction factors for temperature and ionic strength can be updated with knowledge gained from activity coefficient and calcium carbonate research. Calculations presented here show wide discrepancies between temperature correction factors derived from initial and more recent research on calcium carbonate solubility. They are most pronounced in the temperature range of primary concern in potable water supplies.
Florida RO Plant Owned by Citizens
Authors: Harlow Howard W.
Published: February 2018

In response to “A Survey of Problems With Reverse Osmosis Water Treatment” by Eisenberg and Middlebrooks (Journal AWWA August 1984), this author clarifies the ownership of the reverse osmosis plant at Englewood, Florida. The important role of this process in the state's water resources scheme is emphasized.
Mandatory Filtration
Authors: Doty Jack B. , Burba Foster S.
Published: February 2018

One item of S.2649, a proposed amendment to the Safe Drinking Water Act, deals with mandatory filtration. Doty expresses concern that scientific data do not warrant such a requirement, a stance supported by the experiences of several utilities in the Pacific Northwest with pristine, currently unfiltered watersheds. In addition, most small water systems cannot afford filtration plants and maintain reasonable water rates. Burba, whose testimony before Congress as AWWA Water Utility Council chairman was summarized in “Update” (Journal AWWA June 1984), explains that representatives of utilities with unfiltered supplies are exploring the possibility of a variance procedure for such utilities.
Viewpoint – Quality: An Essential Component of Water Resources
Authors: McHugh Richard P.
Published: February 2018

This article is an edited version of an address given at the Hawaii Water Resources Management Invitational Seminar on Feb. 22, 1984, in Honolulu. The author is executive director of the South Central Connecticut Regional Water Authority, a member of the AWWA Standards Council and Resources Division, and chairman of AWWA's Connecticut Section.
Old Water‐New Water: Setting Equitable Water Rates for Suburban Customers
Authors: Miller James W.
Published: February 2018

The rate concepts applied in the Seattle, Wash., metropolitan area address the questions of how water system costs should be split between city and suburban customers, who should pay for suburban growth, and what methods should be used to compute revenues required from wholesale purveyors. Seattle Water Department contracts with suburban wholesale purveyors include allocation of the costs of both old and new facilities, demand metering, and separate rates for supplying “old water” and the additional “new water” needed to meet the demand created by suburban growth.
Development of Revised Primary Drinking Water Regulations
Authors: Cotruvo Joseph A. , Vogt Craig
Published: February 2018

Revised primary drinking water regulations are being developed by the US Environmental Protection Agency in response to the requirements of the Safe Drinking Water Act. National Interim Primary Drinking Water Regulations were established in 1975 with amendments in 1976, 1979, and 1980 for organic and inorganic chemicals, radionuclides, and microbiological contaminants. Development of the revised regulations will involve a comprehensive reassessment of the interim regulations and an examination of the experience gained from implementation of those regulations. This article describes these experiences and current considerations being evaluated for incorporation into the revised regulations.
Postprecipitation in Distribution Systems
Authors: Costello James J.
Published: February 2018

A description of the causes of postprecipitation is followed by a discussion of the effects of the phenomenon on distribution pipelines. In severe cases, the carrying capacity of mains can be reduced by half or water quality at the tap can be adversely affected, causing customer complaints. Since postprecipitation occurs often, operators should be aware of problems that exist and take preventive action through altering treatment practices. Distribution systems should be sampled periodically to determine if problems are present.
Viewpoint – The Need for Filtration of Surface Water Supplies
Authors: Pluntze James C.
Published: February 2018

This article by the director of the state of Washington's drinking water program, Department of Social and Health Services, was prompted by a letter in the September Journal (76: 9: 4) from Jack B. Doty of the Skagit County Public Utility District, Mount Vernon, Wash. Doty opposes AWWA's support for the filtration of surface water supplies, but Pluntze enumerates the many current and potential problems that can occur from the use of unfiltered surface water supplies.
State Regulation of Chloramination
Authors: Hack David J.
Published: February 2018

This article presents the results of a survey conducted by AWWA's Disinfection Committee into the practice of chloramination in US states and territories, including the policies of state water supply regulatory agencies with regard to the use of chloramines.
Viewpoint – Is There a National Water Crisis?
Authors: Durenberger David
Published: February 2018

Using examples from his home state of Minnesota, Senator Durenberger describes the national water crisis. Durenberger points to the need for flood control projects, construction of wastewater treatment facilities, and clean up of hazardous wastes which threaten water supplies. The importance of a national water policy is stressed as is the need to find new ways to organize United States water resources and water programs and to bring new actors, governmental and private, into the policy arena.
Evaluating Sedimentation and Various Filter Media for Removal of Giardia Cysts
Authors: Logsdon Gary S. , Thurman V. Carol , Frindt Edward S. , Stoecker John G.
Published: February 2018

The primary purpose of the pilot study described in this article was to evaluate the efficiency of sedimentation and of coarse anthracite media for removing Giardia cysts. Removal of cysts by sedimentation was observed to range from 65 to 93 percent and was generally similar to removal of turbidity. The coarse anthracite media produced water of inferior quality when alum was the only coagulant, but its performance was found to be improved by the use of a high‐molecular‐weight, slightly anionic polymer. Cyst concentrations appeared to be higher than usual during the initial phase of a filter run, indicating that a filter‐to‐waste period may be desirable. The authors conclude that effective control of Giardia cysts depends on informed application of the multiple‐barrier concept.
Using Polymers With Direct Filtration
Authors: Carns Keith E. , Parker Judith Dickson
Published: February 2018

This article summarizes the research conducted by the East Bay Municipal Utility District, Oakland, Calif., to optimize clay‐polymer coagulation used in conjunction with direct, in‐line filtration to treat low‐turbidity waters. The emphasis is on the district's efforts to ensure that the quality of potable water is consistently high, that chlorine reaction products are minimized, and that all polymer is reacted and removed during filtration.
Polyelectrolyte Selection for Water Treatment
Authors: Ghosh Mriganka M. , Cox Chris D. , Prakash Temkar M.
Published: February 2018

Polyelectrolytes offer many advantages as filtration aids or as primary flocculants. The interrelationship, however, between polymer molecular weight, charge density, polymer dosage, mixing conditions, and the flocculated particle size distribution is not well understood. If an effective method of polymer selection is to be devised, a basic understanding of these interactions is essential. A series of experiments with 12 commercially available polymers showed that in most cases dosage was independent of molecular weight, that a strong correlation appears to exist between the number of charges a molecule carries and its optimum flocculation dosage, and that the size and strength of a floc may be controlled to some extent by proper selection of polymer molecular weight.
USEPA, Navajo Cooperate In Monitoring Program
Authors: Moustakas Michele
Published: February 2018

The author of this letter to the editor writes to correct the negative impression of the United States Environmental Protection Agency (USEPA)'s role in improving water quality on the Navajo reservation given in a “Face to Face” interview in the March 1985 issue of the Journal American Water Works Association. While the Safe Drinking Water Act (SDWA) does not hold the USEPA responsible for conducting baseline studies, the USEPA and the Indian Health Service cooperated in a joint effort in 1979‐80 to collect and analyze baseline samples from every public water system on the Navajo reservation. The author details USEPA efforts to train operators on reservations and to assist Navajo Tribe members in gradually taking a more direct role in their drinking water program. A rebuttal by Susan Williams, who was interviewed in the original article, is included.
Water Reuse in California
Authors: Crook James
Published: February 2018

The state of California actively encourages the use of properly treated wastewater for irrigation and other nonpotable purposes. The Department of Health Services has established statewide wastewater reclamation criteria for various uses, based on the degree of human exposure to pathogens and other contaminants that could be present in treated wastewater. California's program of water reuse has been in place for many years, but has been expanding as more reclaimed wastewater becomes available to provide an economical alternative for purposes other than drinking. The possible health effects and the regulations to ensure safe use of reclaimed water are described in detail.
Obtaining Public Support for Reuse Water
Authors: Bruvold William H.
Published: February 2018

Nine public opinion surveys taken during the past 13 years have shown remarkably similar attitudes toward the use of reclaimed wastewater for drinking and nonpotable purposes. By assessing the results of these surveys, the author recommends strategies for achieving public acceptance of potable reuse water, especially in water‐short areas. Croups of people who are resistant to the idea and those who would be likely to accept the concept are identified. Overall, many of those surveyed believe that the technology exists to treat wastewater sufficiently for potable reuse. A large majority would approve of using reclaimed water for other purposes.
Paying for Reuse Water
Authors: Corssmit C. (Kees) W.
Published: February 2018

To arrive at satisfactory financing plans and price schedules for reuse water, economic feasibility studies of the proposed projects, including consideration of the no‐action alternative, should be undertaken before engaging in more traditional financial planning. This helps to determine the benefits and costs and a proper framework for cost allocations. A market analysis should also be performed to make sure there is a demand for reuse water and to determine what prices people would be willing to pay for it. Typically, revenues obtained from sales of reuse water will be less than for potable water and would possibly not be equal to the cost of serving reuse customers. Methods for redistributing the deficits to other water users are suggested.
Management Audits: A Tool for Water Utilities
Authors: Conley John P.
Published: February 2018

When a water utility must apply for a rate increase, the request almost automatically triggers opposition, resentment, and outcries from ratepayers. At the same time, public utility commissioners also demand proof from the utility that there is ample need and justification for the request. Such proof must support the utility's claim that its business is conducted with maximum efficiency and productivity. Management audits, which have become an accepted part of business life over the past 10 years, have been used for this process by both commissions and utilities. This article explains what a management audit is and what benefits it can provide.
Ozone‐GAC Following Conventional US Drinking Water Treatment
Authors: Maloney Stephen W. , Suffet I.H. (Mel) , Bancroft Keith , Neukrug Howard M.
Published: February 2018

The combination of ozonation followed by granular activated carbon (GAC) has been suggested as a means to improve the cost effectiveness of the GAC process for organics removal. Several combinations of ozonation and chlorination were analyzed for their effects on GAC adsorption. Although ozonation increased biodegradation of dissolved organic carbon, the ozone process was shown to interfere with the ability of GAC to treat volatile halogenated organics. Ozonation appears to increase competition for adsorption sites between volatile halogenated organics and the natural background organic matrix.
Effects of Ozone and Storage Temperature on Giardia Cysts
Authors: Wickramanayake G.B. , Rubin Alan J. , Sproul Otis J.
Published: February 2018

The effects of ozone and storage temperature on the survival of Giardia lamblia cysts, the cause of human giardiasis, and Giardia muris, a parasite of mice, were compared. The viabilities of the cysts were similar over a period of 25 days of storage in the range of ‐6° to 37°C; the optimum temperature for their long‐term survival was determined to be about 5°C. Ozone was extremely effective for inactivating cysts of both Giardia species, with G. muris being consistently more resistant than G. lamblia at pH 7 and 5°C and 25°C.
Removing Fulvic Acid by Lime Softening
Authors: Liao Marcia Yunmen , Randtke Stephen J.
Published: February 2018

Lime softening was found to remove a significant fraction of a fulvic acid extracted from groundwater. Removal of the fulvic acid was attributed to coprecipitation and involved its adsorption onto calcium carbonate crystals during the early stages of the softening reaction. Favorable conditions for removal included a high pH, an excess of divalent calcium, a minimum amount of carbonate, and finely divided calcium carbonate solids of poor crystallinity. Test results suggest that the softening process can be modified to improve the removal of fulvic acid without compromising the removal of hardness.