bluuebunny/crossref_metadata_2025 huggingface dataset:
No DEHP in polybutylene pipe
Authors: Schroer A.H.
Published: February 2018

Prompted by the October 1981 “Percolation and Runoff,” this reader attempts to describe the facts that show conclusively that polybutylene pipes do not contain DEHP.
Drought management: expecting the unexpected
Authors: Woo Viviane
Published: February 2018

Rethinking traditional water supply management approaches and developing both long‐term and short‐term water conservation strategies are crucial to coping with the effects of drought. Studies of droughts in Massachusetts and California have shown that dramatic reductions in water consumption can be obtained with both mandatory and voluntary conservation measures. A key to success in overcoming the effects of drought or other water shortage emergencies is having a preset plan of attack.
Removing soluble organic contaminants by lime‐softening
Authors: Randtke Stephen J. , Thiel Christine E. , Liao Marcia Y. , Yamaya Christopher N.
Published: February 2018

Lime–soda softening effectively removed several humic substances from solution, including a fulvic acid isolated from a local groundwater supply. Removal increased with increased pH, increased amounts of precipitate, and decreased concentrations of TOC and was enhanced significantly by the presence of magnesium or phosphate, especially when a small amount of precipitate was formed. Lime–soda softening achieved at least partial removal of several soluble organic chemicals, although some were not removed to any significant extent. Soluble calcium caused the precipitation of several organic substances in the absence of carbonate ion, indicating that precipitation is a potential removal mechanism. Experimental evidence for other removal mechanisms is discussed.
Rapid‐mix design for mechanisms of alum coagulation
Authors: Amirtharajah A. , Mills Kirk M.
Published: February 2018

An analysis of the type of rapid mixing necessary in specific regions of the stability diagram suggests that it is possible to tailor the design of the rapid‐mix operation to the predominant mode of alum coagulation.
Evaluating the potential for contaminating drinking water from the corrosion of tin‐antimony solder
Authors: Herrera Carlos E. , Ferguson John F. , Benjamin Mark M.
Published: February 2018

This paper presents a theoretical analysis of antimony corrosion, tin corrosion, and galvanic coupling relationships. Results of coupon and field tests conducted to verify the theory are included. The theoretical and experimental results obtained in this study indicate that 95–5 tin‐antimony solder has a potential for replacing lead‐based solders in plumbing systems.
Nuclear power reactor accidents and the role of water system managers
Authors: Davies Sherwood , Bumstead John C.
Published: February 2018

Technical information is given pertaining to release of radioactivity to guide water system managers in preparing for the remote possibility of nuclear reactor accidents.
Creative financing techniques for water utilities
Authors: Williams Paul C.
Published: February 2018

Volatile changes in the municipal bond market have created innovative financing techniques for water utilities' construction programs. Long‐term debt must be structured to appeal to investors and simultaneously keep interest cost low for utilities. Short‐term debt for interim financing can be cost‐effective for larger utilities. Individual utilities must evaluate all options carefully to choose financing techniques most suited to specific needs and to balance risks against costs.
Statewide Water Planning in Georgia
Authors: Kundell James S.
Published: February 2018

The article “Decentralizing Water Resource Planning and Management” by Wright, Cohen, and Health (JOURNAL AWWA July 1982) utilized a study conducted for the U.S. Water Resources Council, State of States: Water Resources Planning and Management. According to these readers, the data presented in that report for the state of Georgia are inaccurate. The report indicates that water management in Georgia is based on the capacity use area. However, since 1972 Georgia has had a statewide water management program, which includes permitting both groundwater and surface water uses in excess of 100,000 gpd.
Contaminated source water and inadequate chlorination led to hepatitis outbreak
Authors: Lippy Edwin C.
Published: February 2018

This reader comments on the article “Viruses in a Community Water Supply Associated With an Outbreak of Gastroenteritis and Infectious Hepatitis” (JOURNAL AWWA June 1982). In a situation in which the source water is contaminated, chlorination is inadequate for pathogen inactivation, and if dependence is placed on a passable coliform record, viruses can go undetected. Chlorine contact time and chlorine injection point should be analyzed carefully under these circumstances.
Creating the Denver Water Department's security program
Authors: Jensen Robert G.
Published: February 2018

The Denver Water Department became aware of its security risks in 1975. Since then, a comprehensive risk management program has evolved that covers all of the department's security exposures ranging from its remote reservoirs to its urban administrative headquarters. An unexpected cost benefit was reduced insurance premiums.
D.C. Area Implements 50‐Year Water Supply Plan
Authors: Sheer Daniel P.
Published: February 2018

Shortly after “Analysis of Water Supply Cost in the Washington (D.C.) Area” by Robert M. Clark et al appeared (JOURNAL AWWA July 1982), the United States Army Corps of Engineers, the mayor of the District of Columbia, and the governors of Maryland and Virginia signed agreements assuring the region of adequate water supply and instream flow into the next century. Regional operation of local supplies, regional sharing of the cost of reservoirs, daily scheduling of upstream releases, and other improvements in the agreement are explained. Also discussed is the technical research conducted for the agreement by the Interstate Commission on the Potomac River Basin (ICPRB).
Maintaining distribution system valves and fire hydrants
Authors: Franklin Bill W.
Published: February 2018

Keeping water distribution system valves and fire hydrants serviceable at all times requires continuous attention. Based on recommended industry practices and standards, the preventive maintenance and system updating program at the St. Louis County Water Co. is described in detail.
Water pricing research needs
Authors: Mann Patrick C.
Published: February 2018

This report reviews the existing knowledge of water pricing, identifies gaps in knowledge about the effects of water rates, and designates areas in which priority research is needed.
Efficiency of point‐of‐use treatment devices
Authors: Regunathan P. , Beauman W.H. , Kreusch E.G.
Published: February 2018

Performances of two devices for point‐of‐use treatment are reported. One device was a combination of a granular activated carbon bed and a precoat filter; the other was a combination of a reverse osmosis unit, a prefilter, and two granular carbon adsorption units. These devices were studied in order to determine the extent to which they were able to remove various organic, inorganic, microbiologic, and particulate contaminants from potable water.
Traffic control—safety's first line of defense
Authors: Wantoch Henry J.
Published: February 2018

Correct traffic control measures should be stressed in all water utility safety programs to protect the public and work crews. Following uniform traffic control standards is necessary, but adjustments should be made for site‐specific conditions.
The interior surface of galvanized steel pipe: a potential factor in corrosion resistance
Authors: Fox Katherine P. , Tate Carol H. , Bowers Eugene
Published: February 2018

This paper describes the differences found in zinc coatings of galvanized pipes manufactured in the United States, Korea, and Australia. Zinc thickness and finish varied with the type of pipe. In an ongoing pilot study, these pipes are being exposed to water containing various concentrations of copper in order to determine whether the surface characteristics of these pipes have any correlation with pitting corrosion.
Control of lead, copper, and iron pipe corrosion in Boston
Authors: Karalekas Peter C. , Ryan Christopher R. , Taylor Floyd B.
Published: February 2018

The water supplied to the Boston metropolitan area is relatively corrosive to piping materials. Contamination of drinking water by lead is a concern because lead pipe that was used extensively in Boston in the late 1800s and the early 1900s was durable enough to be in service in the late 1970s. This paper describes a program established to monitor and control corrosion of lead pipe. The results of the program show that pH adjustment with sodium hydroxide has been effective in reducing both lead and copper corrosion and that a systematic monitoring program is essential in evaluating any proposed corrosion control scheme.
Reusing cooling water in an electric power plant
Authors: Grobmyer William P. , Wilson W.J. , Hancock J.F. , Kurtz M.L.
Published: February 2018

Florida's environmental standards on fluid waste discharge from power plants combined with restrictions on consumptive use of groundwater required the Gainesville Regional Utilities to treat and reuse cooling water for the Deerhaven power generating station. A method for treating and recirculating all cooling water was developed so that zero waste discharge was achieved.
Determining residual chlorine: effect of temperature on the titrametric starch‐iodine end point
Authors: Hatch Gary L. , Yang Vue
Published: February 2018

A quantitative analysis of the effect of temperature on the titrametric starch‐iodine end point demonstrates that when low concentrations of residual chlorine are determined, the temperature of the sample solution must be kept below 20° C for maximum accuracy. A mechanism for the thermal decolorization of the blue starch‐iodine complex is proposed.
Viewpoint – Who pays how much for expanding water supplies?
Authors: Hartman Richard D.
Published: February 2018

In 1980, the Appomattox River Water Authority began an 18‐month process to determine which of its members should contribute and how much should be spent on expanding water supplies. The authority treats and distributes water to the cities of Petersburg and Colonial Heights and the counties of Chesterfield and Dinwiddie, all in Virginia. This article describes negotiations and court procedures undertaken by members of the authority to determine who should pay for improving existing treatment plants and the construction of an additional plant. The final solution involved allocating the capacity of the existing plant based on the previous year's annual consumption. Expansion allocations were determined by taking 1990 projected needs from the consultants' report and subtracting existing plant allocations. Each member was allocated a percent of expansion debt based on future needs divided by total expansion costs. Allocations were not equated with ownership of plant capacity and can be shifted among members as needed.
Variations in particulate matter, algae, and bacteria in an uncovered, finished‐drinking‐water reservoir
Authors: Silverman G.S. , Nagy L.A. , Olson B.H.
Published: February 2018

Tetrachloroethylene has been detected in concentrations ranging from a few micrograms per litre to several milligrams per litre in dead ends of water distribution systems made of vinyl‐toluene‐lined asbestos–cement pipe. About 1600 km (1000 mi) of this lined pipe is being used, primarily in New England. Tetrachloroethylene concentrations can be lessened by flushing and installing continuous bleeders, two of the solutions being suggested to correct this organics problem, which resulted from steps to control corrosion of asbestos–cement pipe.

Physicochemical and microbiological analyses were performed on influent and effluent samples taken from Garvey Reservoir (Los Angeles County, Calif.). Data collected on particle counts and size distributions, total plate count, coliform bacteria, algal counts, chlorophyll, turbidity, copper, and iron were analyzed with a computerized statistical package. The quality of the influent was degraded through biological activity in the reservoir to produce a lower‐quality effluent. Results indicated that algae were associated with increased turbidity and particulate levels and might enhance or support bacterial activity, including physical protection of bacteria against the effects of chlorination.
Treating surface waters for communities in developing countries
Authors: Schulz Christopher R. , Okun Daniel A.
Published: February 2018

Water treatment plants In developing countries should use simplified technologies that require little automation or mechanization to lower capital costs significantly. Operations and maintenance should also be less costly and more suitable for local labor conditions. Use can be made of natural coagulants derived from plants and animals to reduce the cost of treatment.
Using by‐products of an iron removal process to improve water treatment
Authors: Curry Michael D. , Reynolds Marty
Published: February 2018

A conventional treatment for removing iron and manganese from groundwater was used by the village of Roxana, III., but the process did not reduce concentrations of these metals to recommended maximum levels. After using temporary measures, the village began looking at several long‐term alternatives to solve the water quality problems. Of the alternatives considered, oxidation and removal of manganese with potassium permanganate was investigated further in bench studies. Modification of full‐scale treatment effected the removal of manganese by using permanganate feed, ferric hydroxide from the reaction basin as a primary coagulant, and a cationic polymer as a coagulant aid. Reclamation of backwash eliminated a potential problem with disposal of the backwash. Both manganese and iron were reduced to acceptable levels. In addition, the increase in pH helped decrease corrosive water conditions in the distribution system, and the duration of filter runs was lengthened.
Viewpoint – The Los Angeles‐Owens River Aqueduct
Authors: Jones Gerald W.
Published: February 2018

This article highlights the conception and building of the Los Angeles‐Owens River aqueduct which was completed in 1913. The aqueduct supplies water to the San Fernando Valley in California.
Minimum‐flow plumbing fixtures
Authors: Siegrist Robert L.
Published: February 2018

Minimum‐flow plumbing fixtures and household appliances, designed to reduce water consumption by 50 to 90 percent, provide comparable service, are functionally similar to conventional products, are compatible with utility systems, and are potentially cost‐effective. Further development and use of the products are warranted, particularly for domestic uses.
Public water systems and Superfund: recovering losses caused by contamination
Authors: Thomas Frank M.
Published: February 2018

The cost of removing hazardous substances from drinking water sources or the cost of taking remedial action in the event of long‐term source contamination may be recoverable through the federal Superfund—if the contamination is known to have occurred prior to December 1980 and the source has been threatened or affected at some time since then. Such claims must be filed before Dec. 11, 1983. Provisions of the Comprehensive Environmental Response, Compensation, and Liability Act, descriptions of court rulings in connection with the act, and procedures for filing claims against those responsible for contamination are discussed.
Engineering water wells
Authors: Carpenter Carl H.
Published: February 2018

As energy costs rise, groundwater users should seek to obtain the most efficient wells possible by means of hydrogeologic investigations, test holes, and engineered designs. Appropriate methods of developing new water wells are discussed.
Trends in the real price off water
Authors: Mann Patrick C. , LeFrancois Paul R.
Published: February 2018

Increases in water rates have tended to lag behind the rate of inflation during the past two decades as evidenced by a study of 152 water utilities. The real price of water, when adjusted for the rapid rate of inflation during the past decade, is less, in many cases, than during the 1960s. The price of water for industrial use has risen at a higher rate than the price of water for commercial or residential use.
Determining velocity gradients in laboratory and full‐scale systems
Authors: Cornwell David A. , Bishop Mark M.
Published: February 2018

Simulation of plant flocculators can be accomplished by using jar testing equipment. Similar conditions should be maintained between laboratory and full‐scale work. In this article several G curves for jar testing are presented that allow different small‐scale geometries to be used. Power curves were also developed and correlated to power numbers available in the literature for large impellers. Subsequently, a procedure is presented for determining the full‐scale G values.
Hanke answers critic
Authors: Hanke Steve H.
Published: February 2018

In this letter, the author answers Bill Foster's letter “Privatization Panned” (JOURNAL AWWA July 1983) to explain that he did not state or imply that public employees are either “stupid” or “corrupt,” nor that there are no efficient public operations. Foster had made these assumptions based on the author's interview with David Preston in “Face to Face” (JOURNAL AWWA May 1983).
Viewpoint – Conservation Makes Sense for All
Authors: Brigham Arthur P.
Published: February 2018

In this issue of “Viewpoint,” the author advocates a sustained water conservation program. Conservation is not simply reducing waste, but the act of keeping or protecting from loss or injury. The author discusses the following points in favor of utilizing a sustained water conservation program: such a program is good for everyone; sustained water‐saving and waste reduction will not harm revenues if good public relations programs are implemented; water conservation programs can be coordinated with other conservation programs such as wastewater management, land‐use planning, recreation, and economic development; development and exchange of information on management practices and water‐saving techniques with business and multi‐family dwellings; and mandatory installation of water‐saving devices.
Telemetric control of water distribution systems
Authors: Von Rader John E.
Published: February 2018

Applications of telemetry to water distribution systems range from simple remote control systems to sophisticated digital software packages programmed for specific conditions. The capabilities of analog and digital systems are explained and compared.
Maintaining distribution system valves
Authors: Skorcz Dan
Published: February 2018

A valve maintenance program implemented in economical stages can result in immediate improvement in distribution system reliability. Suggestions are given tor planning a program, exercising valves, and maintaining records.
Self‐esteem in the workplace
Authors: Barefield Robert F.
Published: February 2018

The effect of workers' low self‐esteem on the operation of organizations is discussed, and examples of how persons with low self‐esteem hinder job performance are given. An appropriate managerial response to the self‐esteem needs of employees is suggested.
Adsorption of humic substances: the effects of heterogeneity and system characteristics
Authors: Weber Walter J. , Voice Thomas C. , Jodellah Abdullah
Published: February 2018

The study from which this article derives focused on the identification and quantification of parameters that affect the adsorption of humic substances by activated carbon and on the application of these findings to water treatment practice. Results reported here demonstrate the dependence of adsorption on pH, initial concentration of humic material, carbon dosage and particle size, and levels of various inorganic ions in solution. Many of the observed effects are attributable to the fact that humic substances are mixtures of compounds and that their adsorption is therefore a multicomponent process. The distribution of adsorptivities within these mixtures appears to vary with the presence of certain ions, most notably Ca2+ and Mg2+. These findings have been applied to bench‐scale granular carbon columns and to powdered‐carbon slurry systems. The results are discussed from both theoretical and application points of view.
Developments in water softening by means of pellet reactors
Authors: Graveland A. , van Dijk J.C. , de Moel P.J. , Oomen J.H.C.M.
Published: February 2018

The Dutch experience with pellet reactors is reviewed, with special emphasis on a new reactor concept based on crystallization on a seeding material with sodium hydroxide. During long‐term, full‐scale operations this concept has provided low‐cost softening and eliminated problems with solids disposal.
Cathodic Protection of Water Storage Tanks
Authors: Bushman James B. , Kroon David H.
Published: February 2018

Providing cathodic devices that protect against corrosion in water storage tanks defers or, in some cases, eliminates the need to recoat submerged surfaces, making such systems economical over the long term. Some types of new anode materials have a design life of 10 to 20 years, whereas aluminum anodes must be replaced annually. Automatic electric current control systems are also available to compensate for fluctuating conditions, to measure the potential in the electrolyte, and to lower the electric consumption of cathodic protection systems.
Overland Flow for Iron Removal From Potable Water
Authors: Zirschky John , Carlson Liisa
Published: February 2018

Overland flow, an effective wastewater treatment process, can also be used for potable water treatment. Many groundwaters contain excessive amounts of ferrous iron that result in a water of poor aesthetic quality. The natural reaeration that occurs during overland flow oxidizes ferrous iron to the more insoluble ferric form. The resulting precipitate then settles on the slope. An existing overland‐flow treatment system in Salo, Finland, achieves 97 percent iron and manganese removal. A brief description of that treatment system is presented.
Viewpoint – Service or Disservice?
Authors: Scott James C.
Published: February 2018

This article is an edited version of a paper presented at AWWA's 1983 Annual Conference in Las Vegas. The author, a project manager specializing in water and wastewater treatment plant design with Black and Veatch, Detroit, Mich., advocates public persuasion about water policies and improvements rather than unarguable prescriptions.
Negotiating Construction Claims
Authors: Duck Donald J.
Published: February 2018

Today's uncertain construction costs coupled with overly competitive bidding make cost overruns and claims by contractors in the heavy construction industry almost inevitable. Negotiating such claims, although time‐consuming, can be an equitable means of settlement. Each party's position must be documented from the beginning of the project before claims exist, and positions must be clearly defined when negotiations take place. All parties must be willing to compromise. Tactics that permit settlement by negotiation are described.
Acid Precipitation and Drinking Water Supplies
Authors: Reed John S. , Henningson John C.
Published: February 2018

Three areas of concern about the effect of acid precipitation on drinking water supplies are evaluated—the increased levels of heavy metals in raw water, biological imbalances in water supplies, and increased corrosivity of delivered water. Although two thirds of the US water supplies are corrosive, the extent to which this corrosivity is related to acid precipitation is unknown. Shallow wells in the Adirondack Mountains that are directly recharged by rainfall are exceptionally corrosive. Potential management practices are suggested.
Air Stripping of Taste and Odor Compounds From Water
Authors: Lalezary Shahla , Pirbazari Massoud , McGuire Michael J. , Krasner Stuart W
Published: February 2018

The presence of earthy, musty odors in water supplies and the associated problems faced by the water industry are generally acknowledged. Because compounds that cause taste and odor problems in drinking water have extremely low threshold‐odor concentrations (as low as 2 ng/L), their precise quantification has thus far been impracticable. This research addresses the application of the closed‐loop stripping analysis technique in quantification of air stripping for removal of five specific taste and odor compounds from water.
Studies on Home Water Treatment Systems
Authors: Bell Frank A. , Perry Donald L. , Smith James K. , Lynch Stephen C.
Published: February 2018

Commercially available home water treatment systems were tested under a US Environmental Protection Agency grant to compare the efficiency of more than 30 units in removing volatile organic chemicals and to investigate the microbiological and endotoxin concentrations found in the filter effluents. Statistical information on every unit tested is presented in a series of tables.
The Coagulation of Humic Substances by Means of Aluminum Salts
Authors: Dempsey Brian A. , Ganho Rui M. , O'Melia Charles R.
Published: February 2018

Mechanisms for the removal of humic substances from water by coagulation with aluminum salts were studied by means of conventional jar test procedures. Independent variables were the type and concentration of humic substance, the type and concentration of aluminum coagulant, and pH. Removal of humic substances was determined by measuring total organic carbon or by direct ultraviolet spectroscopy. Under some experimental conditions the humic substances were directly precipitated by soluble aluminum species; under other conditions they were removed by adsorption on Al(OH)3(s). Polyaluminum chloride, an unconventional coagulant in the United States, is a promising alternative to alum for removing humic substances from some water supplies.
Legal Means of Protecting Aquifers
Authors: Selig Edward I.
Published: February 2018

Various legal grounds for filing suit to recover the costs of cleanup of contaminated underground water supply sources are summarized. The author also outlines prudent measures that a plaintiff utility should take in preparing and presenting evidence and in raising revenues to meet the immediate costs of additional water treatment while pursuing relief from the party responsible for the contamination.
Green Sand No More
Authors: Stevenson David G.
Published: February 2018

Although the article “Chlorination‐Filtration for Iron and Manganese Removal” (Journal AWWA January 1984) lists various treatment sequences for this procedure, no mention is made of the use of catalytic media within the filter. Plain aeration, sometimes with pH adjustment and sometimes with chlorination, followed by catalytic media filtration, has been a common practice for iron and manganese removal in the United Kingdom. Manganese green sand is seldom used for this treatment process.
The Hardhof Groundwater Complex in Zurich
Authors: Schalekamp Maarten
Published: February 2018

One component of the Zurich, Switzerland, water system, the Hardhof groundwater treatment plant, was recently improved to provide additional capacity. Located in an urban area, the new complex incorporates features that protect the water quality and also provide open landscaped areas for public use. The groundwater supply is enhanced by artificial injection of surface water.
Jordan Meets Water Supply Challenges
Authors: Pruitt L. Lynn , Thoem Robert L.
Published: February 2018

A new water system for the Amman, Jordan, metropolitan area will be completed in early 1985. The surface water supply is taken from a canal at an elevation of 230 m below sea level and pumped in a series of steps to a treatment plant near the city at an elevation of 1040 m above sea level. The 121‐ML (32‐mgd) initial capacity of the system will approximately double the supply currently available for the city's nearly 1 million inhabitants.
THM Precursors in the Environment
Authors: Joyce Wendy Saracen , DiGiano Francis A. , Uden Peter C.
Published: February 2018

The characterization of trihalomethane (THM) precursors and their eventual removal from water are elusive goals. Conflicting and highly variable results exist. Precursors of THMs were examined by sampling humic substances from three regions in Massachusetts with dissimilar geographic and geomorphic natures. Fulvic acid fractions from soil and water were analyzed for carbon and then chlorinated to produce THMs. Microwave emission detection showed little variation in THM production between sources but revealed differences between low‐ and high‐molecular‐weight fractions. More dense chloroform fractions tended to contain greater amounts of carbon, suggesting that their removal will achieve the greatest THM reduction.
Computerized Distribution Records—CADD Paves the Way
Authors: Curtiss John F. , Lohmiller Paul A.
Published: February 2018

The findings of a water audit and leak detection investigation generated input for a new computer‐aided drafting and design system (CADD) for the city of Des Plaines, Ill. Installation of the computerized system will upgrade the usefulness and accuracy of documents pertaining to the city's water and sewer systems. Immediate benefits were realized from the discovery of significant leakage, and long‐range benefits will be realized from the inherent flexibility of the CADD system and the ease with which up‐to‐date records can be maintained. Graphic overlays on base maps of the city can be generated in hard‐copy form to produce the graphic and nongraphic data needed for a given use. These data, stored in CADD, will also be of use to other municipal departments.
Calibrating Water System Models
Authors: Cesario A. Lee , Davis J. O.
Published: February 2018

Calibration enables a computer model to simulate field conditions accurately. Telemetry data and field measurements of the system provide base data for calibration, but computer programs that automatically extract and compare pertinent data with simulated values can aid the process. Once calibrated, the model can be used with a great degree of confidence as a predictor and as a benchmark case for further analyses. The degree of accuracy to which a model should be fine‐tuned is related to the complexity of the model and to the purpose of the study.
Sedimentation Success From Modified Jar Tests
Authors: Reed Gregory D. , Reece David A.
Published: February 2018

Delivery of clear water from settling basins to filtration systems is important for the smooth operation of a treatment plant. But operators work at a disadvantage when they cannot determine what is happening during the sedimentation process. Incomplete settling allows turbid outflows to reach filters, shortening their runs and adding to water quality costs. A modified jar test method for modeling basin behavior has been designed. It uses a hydraulic comparison equation sensitive to basin flow rates, water residence times, and flocculant dosages. When properly calibrated, it can reflect actual basin performance, detect problems, and point to areas where solutions may be found.
Seasonal and Time‐of‐Day Pricing
Authors: Russell John D.
Published: February 2018

Some water utilities are using or considering the use of seasonal rates as a means of reducing peak‐hour and peak‐day demands, conserving water supplies, or better matching revenues with costs. The winter‐summer form of seasonal rate is easier to administer than the summer excess rate but is not as effective in recovering costs or in changing consumption. If it is to be successful, a seasonal rate program must be carefully planned, with adequate time allowed for customer education and for development of administrative and computer procedures.
The Costs of Compliance
Authors: Kurland Sande S.
Published: February 2018

In response to Arizona Senator Dennis DeConcini's “Viewpoint” in the Journal AWWA, August 1984, the writer urges that funding be supplied for the water supply industry prior to establishment of any legislation that would require potentially costly compliance with new standards.
Conserving Energy in Water Systems
Authors: Daffer Robert A.
Published: February 2018

The author provides an overview of alternative sources of energy that could be practical for special water system applications and outlines ideas for saving power from conventional sources. The demand for energy is an increasingly important consideration for the design and operation of all components of a water treatment and distribution system. The most obvious energy‐saver is, of course, the use of gravity wherever possible.
Article Applauded, Sources Expanded
Authors: Caufield James D.
Published: February 2018

In response to an article in the October 1984 issue of the Journal AWWA, the author of this letter to the editor supplies information on fish hatcheries using biological filtration. The earlier article by Bruce E. Rittman and Vernon L. Snoeyink was entitled “Achieving Biologically Stable Drinking Water” and dealt with the status in the water industry of the removal of ammonium‐nitrogen and related organics and metals. Caufield also provides references to additional literature dealing with the subject.
Roundtable – Drinking Water Research: How Are We Doing?
Authors: Miller Bill , Mannion Jack , McGuire Mike , Kühn Wolfgang , Miller Bill , Singley Ed , Kühn Wolfgang
Published: February 2018

Priorities and goals of water industry research in North America were discussed during the 1984 annual conference in Dallas on June 11. Participants were: Wolfgang Kühn of the Engler‐Bunte Institute, Karlsruhe, Federal Republic of West Germany; Michael J. McGuire, water quality manager with The Metropolitan Water District of Southern California; William H. Miller, manager of the Denver Water Department; and J. Edward Singley, vice‐president of J.M. Montgomery Engineers, Gainseville, Fla. John B. Mannion, director of development and communications for the AWWA Research Foundation, was moderator of the roundtable.
Misinterpretation of Soviet View Corrected
Authors: Vasiliev Vladimir S.
Published: February 2018

The author of this letter to the editor corrects some errors in a “Viewpoint” article in the October 1984 Journal American Water Works Association. The author points out that references in the earlier article to “waterless” technologies did not mean “water reuse.” Secondly, the author states that the Safe Drinking Water Act (SDWA) falls into the category of regulation of the quality of consumer products rather than environmental regulations and that he is aware that it is not the only form of federal regulation of environmental quality in the United States.
Removing Giardia Cysts With Slow Sand Filtration
Authors: Bellamy William D. , Silverman Gary P. , Hendricks David W. , Logsdon Gary S.
Published: February 2018

Pilot‐plant studies were undertaken to determine the efficiency of slow‐rate sand filters in removing Giardia cysts and other substances. The filters removed virtually 100 percent of the Giardia cysts, 96 percent of standard plate count bacteria, and 98 percent of particles. Because of the efficiency and the passive nature of slow‐rate sand filtration, this technology is especially appropriate for small water systems.
Removing Color Caused by Humic Acids
Authors: Edwards Gerald A. , Amirtharajah A.
Published: February 2018

Optimum domains for the removal of color during the coagulation process were studied in a series of jar tests and diagrammed as an aid to the design and operation of water treatment plants. The mechanisms for the removal of color associated with humic acids seem to be closely related to those associated with the removal of turbidity.
Polyaluminum Chloride and Alum Coagulation of Clay‐Fulvic Acid Suspensions
Authors: Dempsey Brian A. , Sheu Hueymeei , Ahmed T.M. Tanzeer , Mentink Jack
Published: February 2018

Polyaluminum chloride is an unconventional coagulant that will soon be introduced to the US market. It is produced by partial hydrolysis of aluminum chloride and is thought to consist of stable cationic polymers of aluminum. The benefits of polyaluminum chloride relative to alum have been investigated as a function of pH, raw water composition, and mixing conditions. Conditions are outlined that might indicate the effective use of polyaluminum chloride instead of alum.
Removing Humic Substances by Chemical Treatment and Adsorption
Authors: Weber Walter J. , Jodellah Abdullah M.
Published: February 2018

Alum coagulation and lime softening exhibited variable effectiveness for removing the total organic carbon (TOC) associated with humic substances in water supplies. Pretreatment with alum or lime also affected the subsequent adsorption of TOC by granular activated carbon, with alum coagulation generally improving overall adsorbability. The effectiveness of pretreatment for removing TOC and for altering the adsorption characteristics of residual humics appears to depend on the source and type of the humic material.
Energy Requirements for Air Stripping Trihalomethanes
Authors: Roberts Paul V. , Levy James A.
Published: February 2018

In process design for air stripping of trihalomethanes (THMs) the gas‐phase, mass‐transfer resistance must be taken into account to ensure efficient operation. In most cases, it should be possible to attain effective THM control with an energy expenditure of less than 0.1 kW · h/m3 of treated water. Mechanical surface aeration and countercurrent, packed‐column air stripping require approximately the same amounts of energy to achieve the same treatment efficiency. Considerable energy savings can be realized by choosing a multistage configuration in surface aeration.
The Advantages of Dissolved‐air Flotation for Water Treatment
Authors: Zabel Thomas
Published: February 2018

Dissolved‐air flotation as a primary clarification stage for the production of potable water is particularly effective for the treatment of algae‐laden waters and low‐turbidity, highly colored waters. Flotation has several process advantages over sedimentation—it can produce better water quality; it can be operated at high surface loadings, resulting in relatively small and shallow plants; and it can be started up quickly, with a steady water quality being achieved within 45 min. Also, the solids concentration of the sludge produced is significantly higher (about 3 percent) than that of sludge produced by sedimentation. This article discusses the design parameters for dissolved‐air flotation plants and gives detailed information on the design of flocculation and flotation tanks, the air saturation system, the production of microbubbles, and the different sludge removal systems that can be used. Performance data are given for flotation plants used for clarification of several raw waters, with special emphasis on the treatment of algae‐laden waters and low‐turbidity, highly colored waters. A cost comparison between flotation and sedimentation is also presented, taking into account both capital and operating costs. The overall costs of the two processes are similar. Therefore, the final process selection will depend on the additional advantages offered by both processes.
Chlorinated Organics in Simulated Groundwater Environments
Authors: Parsons Frances , Lage Gladys B.
Published: February 2018

Tetrachloromethane and 1,1, 1‐trichloroethane were transformed in microcosms composed of aquifer materials to trichloromethane and 1,1‐dichloroethane, respectively. Further observations of tri‐ and tetrachloroethene in microcosms demonstrated the transformation of these compounds to dichloroethene. Biotransformation products of these four solvents by freshwater sediment microbiota, in sealed static microcosms, were determined by gas chromatography during incubation at ambient temperatures in the dark for periods of up to 16 weeks. Under conditions of neutral to acid pH, reductive potential, and the absence of oxygen and light, reductive dehalogenation of these four compounds occurred. Chlorinated alkenes were consistently more resistant to biotransformation than the chlorinated alkanes.
Viewpoint – Extending Rural Water Supplies in Developing Countries
Authors: Eaton David J.
Published: February 2018

The author, an associate professor at The University of Texas at Austin, developed his concepts on rural water supplies as a Senior Fulbright Research Scholar at the University of Delft, the Netherlands, and through discussions with L. Huisman, Gerard Rohlich, and Abel Wolman.
Tomorrow's Technology for Today's Problems
Authors: Roberts Kenneth F.
Published: February 2018

The problems associated with aging underground distribution networks in the United Kingdom are being addressed at the national and regional levels. This article details one water authority's use of telemetry to reduce stresses on distribution networks and extend the life of underground assets. It also discusses the 1974 reorganization of water services in Great Britain, the new approach to financing distribution system maintenance, and policies regarding renovation versus replacement of mains.
Health Effects of Indirect Potable Water Reuse
Authors: Nellor Margaret H. , Baird Rodger B. , Smyth John R.
Published: February 2018

A five‐year, multidisciplinary research project was undertaken to evaluate the effects on health of using treated wastewater for groundwater replenishment. The study focused on the Whittier Narrows Groundwater Replenishment Project in Los Angeles County, Calif., where replenishment with a mixture of imported river water, stormwater, and reclaimed wastewater has been practiced since 1962. Results of the study showed that the proportion of reclaimed water currently used for replenishment had no measurable impact on either groundwater quality or human health. Recommendations for optimization of groundwater replenishment with reclaimed water are included.
Factors Controlling the Removal of Organic Pollutants in Ozone Reactors
Authors: Gurol Mirat D.
Published: February 2018

According to a model developed during this study, the efficiency of removing organic contaminants in ozone reactors is determined mainly by the reactivity and volatility of the contaminants. The chemical composition of the water, the mass transfer characteristics of the reactor, and certain operational conditions (flow rates of the gas and water, concentration of ozone in the applied gas stream, and detention time) were identified as the process parameters that control the performance of ozone reactors. Once the methodology has been developed to measure all key parameters, the model can be used to evaluate different operational alternatives for optimum performance of ozone reactors and to make performance and cost comparisons between ozonation and other processes, such as activated carbon adsorption and air stripping.
Modern Techniques in Well Design
Authors: Williams Dennis E.
Published: February 2018

A direct benefit of efficient wells is reduced pumping costs. Well efficiency is controlled by several factors, including aquifer, drilling damage, and turbulent‐flow losses at or near the well screen. Screen entrance velocity is not a critical design factor if values are less than 2–4 fps (0.6–1.2 m/s). For most wells, the required open area of a screen need only be 3–5 percent. A new method of designing minimum length of well screen based on laminar flow‐turbulent flow considerations is presented, along with a simple field test to calculate the efficiency of an existing well or to provide a criterion for termination of development of a newly constructed well.
Controlling Trihalomethane Formation Potential by Chemical Treatment and Adsorption
Authors: Jodellah Abdullah M. , Weber Walter J.
Published: February 2018

Removal of total organic carbon (TOC) from humic solutions by adsorption, alum coagulation, lime softening, or a combination of chemical treatment and adsorption generally resulted in a reduction in the formation of trihalomethanes (THMs). Although high levels of TOC removal by adsorption were found to increase incremental THM reduction, high levels of TOC removal by alum coagulation or lime softening generally decreased the incremental reduction of THM formation, as reflected by the THM formation potential (THMFP). Because greater removal of TOC does not necessarily produce greater reduction of THMFP, it is suggested that water treatment systems intended to remove THMs should be optimized specifically to control that parameter rather than to maximize TOC removal.
Planning and Implementing a Dual Distribution System
Authors: Gallier W. Thomas
Published: February 2018

The town of Castle Rock, Colo., has developed a dual distribution system that will provide metered nonpotable as well as potable water to most new residential and business properties In the community. The system is designed to conserve a deep, nontributary underground water supply while providing a more effective means of disposing of tertiary treated wastewater.
Lead Dissolution From Soldered Joints
Authors: Birden Hudson H. , Calabrese Edward J. , Stoddard Ann
Published: February 2018

Levels of lead in tap water exceeding the US Environmental Protection Agency primary drinking water standard of 0.05 mg/L have been reported in several communities in Connecticut. Investigation revealed that the lead originates from leaching of soldered joints in recently constructed plumbing systems, not from source water supplies. This study examined the phenomenon quantitatively with plumbing runs fabricated from the most commonly used plumbing materials and solder formulations. Tests of two groundwater sources of different corrosivity run through soldered copper piping demonstrated levels of lead well in excess of the USEPA standard. The levels of lead declined with time and varied with the type of solder used and the corrosivity of the water. Elimination of lead in solders and education of the public are suggested as countermeasures.
Viewpoint – Reagan Tax Reform Inhibits Public Debt
Authors: Giglio Joseph M.
Published: February 2018

This article discusses the impact of President Reagan's tax proposals, which were released to the US Congress on May 28, 1985, on the ability of state and local governments to finance needed infrastructure improvements at reasonable cost. Topics covered include: accelerated cost recovery system, investment tax credit, tax‐exempt financing, and long‐term service contracts for tax‐exempt facilities.
Slow Sand Filtration: Influences of Selected Process Variables
Authors: Bellamy William D. , Hendricks David W. , Logsdon Gary S.
Published: February 2018

Biological activity within the sand bed had the strongest influence on removal efficiency of total coliform bacteria by slow sand filtration, as determined by six pilot filters (shown above). Temperature, sand bed depth, and sand size also had strong influence.
Hydraulic Behavior of Declining‐Rate Filtration
Authors: Arboleda‐Valencia Jorgé , Giraldo Roberto , Snel Herman
Published: February 2018

One of the key difficulties in the practical application of declining‐rate filtration is the complexity of the hydraulic calculations used to predict the flows and levels in each filter unit The mathematical model described in this article attempts to ease such difficulties and to show how, beginning with basic hydraulic principles, it is possible to determine the different operational parameters.
Design and Operation of a Slow Sand Filter
Authors: Seelaus Timothy J. , Hendricks David W. , Janonis Brian A.
Published: February 2018

The design experience at Empire, Colo., and the postdesign evaluation have provided knowledge about the efficiency of the slow sand filtration process at full‐scale and the basis for recommendations concerning slow sand filtration practice. Operation of the filter required daily inspection plus measurement of water depth and effluent turbidity, along with monthly scraping. Scraping required only two workhours, however, and only 0.2 in. (0.5 cm) of surface was removed. The projected life of the sand bed at this rate of removal is 15 years, with a residual depth of 1 ft (0.3 m). Giardia cysts were found in the raw water on five occasions, but none were found in the finished water. Microscopic organisms and particles were found in the raw water but either zero or rare numbers were found in the finished water.