bluuebunny/crossref_metadata_2025 huggingface dataset:
MTBE in Southern California water
Authors: Dale Melissa S. , Koch Bart , Losee Richard F. , Crofts Eric W. , Davis Marshall K.
Published: February 2018

Motorized recreational watercraft were the predominant mode of contamination in reservoirs.

Methyl tertiary butyl ether (MTBE) is a common fuel oxygenate used in motor vehicle fuels to control emissions and boost octane. It is more water‐soluble than other fuel constituents and does not adsorb well to substrates such as soil. It can contaminate groundwater supplies through leaking underground fuel storage tanks and pipelines, and through spills, urban storm runoff, and precipitation. It can also contaminate open water reservoirs through exhaust from motorized watercraft. The Metropolitan Water District of Southern California surveyed six reservoirs that supply drinking water in Southern California. Recreation on these reservoirs ranged from none at all to high activity with personal watercraft. It was found that motorized watercraft can contribute a significant amount of MTBE to the water supply.
The 12‐Hour “8‐Hour” Day
Authors: Craft Susan
Published: February 2018

Operators of water and wastewater systems for five small towns in Michigan have jobs that may seem highly demanding, and very long, to employees of larger utilities.
Improving Filtration of Cryptosporidium
Authors: Shaw Kathy , Walker Steve , Koopman Ben
Published: February 2018

Surface coating of hydrous iron aluminum oxide on Ottawa sand was investigated as a means of improving the removal of Cryptosporidium oocysts from water by filtration. Coating the sand increased the zeta potential from −40 to +45 mV at pH 7.0, increasing the potential for interaction with the negatively charged (−25 mV at pH 7.0) Cryptosporidium oocysts. Water seeded with Cryptosporidium oocysts was passed through parallel columns of uncoated and coated sand at superficial velocities of 200–800 m/d (3.5–14 gpm/sq ft) and column lengths of 100–400 mm (4–16 in.). In every trial, coated sand removed significantly more oocysts than uncoated sand. Filter coefficients of coated sand were 2.9 times as high as those of uncoated sand, indicating that coating can significantly improve the removal of Cryptosporidium by granular media filters.
Water, wastewater community scrambling to make sense of USEPA action declaring chlorine gas a restricted‐use pesticide
Authors: Scharfenaker Mark A.
Published: February 2018

This column discusses the latest in a series of US Environmental Protection Agency's Office of Pesticide Programs (OPP) notices declaring chlorine gas to be a restricted‐use pesticide (RUP) that will require treatment plants using it as a disinfectant to have at least one trained and certified “pesticide applicator” present during all operations. A listing of internet resources on the subject is given, along with an explanation of the essentials of the Federal Insecticide, Fungicide, and Rodenticide Act.
Supplier Not Liable for Underground Tank Leakage
Authors: Stiegler Mayo H.
Published: February 2018

The Supreme Court of Alaska ruled that a petroleum supplier could not be held strictly liable for groundwater contaminated by fuel leaking from a gas station's underground tanks.
Rapid Growth in Submetering Produces Benefits and Problems
Authors: Bennett Dick
Published: February 2018

This article discusses the benefits and problems of the rapid growth of submetering.
Right to Sue Under Clean Water Act Established
Authors: Stiegler Mayo H.
Published: February 2018

The owner of a lake 4 mi (6 km) downstream from a smelting facility who suffered injuries as a result of pollution to the lake could seek relief under the Clean Water Act (CWA), according to the US Court of Appeals for the Fourth Circuit.
trend beat
Authors: Parmelee Mary A.
Published: February 2018

This column reports on aggressive recruiting strategies used by a company to increase its staff by 50% that include: open houses; job fairs; Internet postings; referrals from existing employees; and, a retention strategy that focuses on employee training and development. Another company instituted programs targeting female employees that included: programs to ensure women received their share of mentoring and premier assignments; promoting a better balance between work and family life for men and women; and, linking executive compensation to successful implementation of these goals.
And You Thought the Lead and Copper Rule Was Challenging…
Authors: Grunenfelder Gregg
Published: February 2018

This article discusses three new rules for arsenic, groundwater, and radon, the result of the 1996 amendments to the Safe Drinking Water Act, and the dramatic impact on small systems they will have. Because of the sources of supply typically serving small systems (relatively shallow groundwater sources) and because of the small rate bases available to those systems to pay implementation costs, small systems will be particularly affected.
Retrofit Realities
Authors: Deoreo William B. , Dietemann Allan , Skeel Tim , Mayer Peter W. , Lewis David M. , Smith Jenna
Published: February 2018

This paper discusses the Seattle Home Water Conservation Study (SHWCS) and compares it with the American Water Works Association Research Foundation's Residential End Uses of Water Study (REUWS). SHWCS is the first such study using samples taken from the original REUWS group. It provides important information on water‐conserving fixtures and appliances through a before‐and‐after paired comparison of water use patterns. Precise data were obtained on reductions in per capita cold and hot water use that were achieved by retrofitting plumbing fixtures and appliances with new, high‐efficiency devices. The most effective fixtures evaluated in the study, based on measured savings, were toilets, clothes washers, and faucet aerators. All told, the retrofit in Seattle reduced water use from around 70 gpcd to 40 gpcd or less by using new high‐efficiency fixtures and appliances.
Stalking the Wily Computer
Authors: Hoffbuhr Jack W.
Published: February 2018

In his column, AWWA Executive Director Jack Hoffbuhr discusses how our society has entered the Information Age and how information technology affects everyone and everything in our society. He gives pointers on planning a successful technology conversion for businesses, and says that planning, flexibility, and training are the keys to exploiting the opportunities that information technology offers.
Do the Right Thing
Authors: Yarlott Nelson
Published: February 2018

This article discusses how important water treatment plant operators are as the front‐line troops in today's battles to meet federal mandates and continue to ensure public health protection.
Effects of SPENT FILTER BACKWASH recycle ON CRYPTOSPORIDIUM REMOVAL
Authors: Cornwell David A. , Macphee Michael J.
Published: February 2018

Pilot studies were conducted to investigate the effect of recycling spent filter backwash water (SFBW) on Cryptosporidium and particle removal during conventional sedimentation and dual‐media filtration. When SFBW recycle configurations (3,000–19,000 oocysts/100 L) were used, Cryptosporidium concentrations in settled water were as low as or lower than when no recycle was used (6,000–22,000 oocysts/100 L). Filtered water oocyst concentrations were typically below the detection limit of 1 oocyst/120 gal (~0.25/100 L). Overall process removal was about 5 log without recycle and about 5.7 log for each recycle scenario based on calculations using raw Cryptosporidium concentrations and filtered water detection levels. As with Cryptosporidium removal, removal of turbidity and particles > 2 μm for the entire process (sedimentation + filtration) was similar for operations with and without recycle. Typical median filtered water concentrations for particles > 2 μm were < 0.5 particles/mL for all recycle scenarios, including no recycle. Similarly, settled and filtered water turbidity levels for all studies were typically < 2 and < 0.03 ntu, respectively.
DURABILITY OF WOOD‐BASED versus COAL‐BASED GAC
Authors: Grens Bradley K. , Werth Charles J.
Published: February 2018

Wood‐based granular activated carbon (GAC) has been used successfully both in pilot applications and in full‐scale filter applications, but its durability during backwashing has not been evaluated in a side‐by‐side study with bituminous coal‐based GAC. The objective of this study was to compare the durability of these two types of GAC when subjected to 500 cycles of backwashing with an air–water wash system. GAC durability was evaluated by measuring the change in carbon bed height, pressure drop, filter effluent water quality, and particle characteristics as a function of backwashing. The results showed that the durability of the wood‐based and the coal‐based GAC was similar throughout the duration of the study.
Texas “Water Quality Protection Zones” Ruled Unconstitutional
Authors: Stiegler Mayo H.
Published: February 2018

The Supreme Court of Texas struck down as unconstitutional a state law that allowed certain landowners to create water quality protection zones within the extraterritorial jurisdictions of certain Texas cities.
Making sense of the Unregulated Contaminant Monitoring Rule
Authors: Scharfenaker Mark A.
Published: February 2018

This article discusses the Unregulated Contaminant Monitoring Rule (UCMR), mandated by the 1996 Safe Drinking Water Act amendments, which is a dynamic program comprising a growing collection of rulemakings that have arisen to replace requirements first established in 1988 for assessing the occurrence of unregulated contaminants. The current format of the UCMR is just the first version of a rulemaking process that will repeat every five years in step with regularly updated Contaminant Candidate Lists (CCLs) and periodic regulatory determinations by the US Environmental Protection Agency (USEPA). This article distinguishes between the overall UCMR program and the first five‐year cycle of the program that started Jan.1, 2001, and runs through the end of 2005, which in an abbreviated form is UCMR1. USEPA plans to propose and finalize UCMR2 requirements in time for their start date of Jan. 1, 2006. A list of internet resources is given, along with water system monitoring schedules for the UCMR1 five‐year cycle, assessment monitoring contaminants, screening survey contaminants, prescreen testing contaminants, monitoring frequency for chemicals, and USEPA regional contacts for UCMR activities.
Cyber Business Permeating Water Utilities
Authors: Parmelee Mary A.
Published: February 2018

This article discusses how utilities are not just using the Internet to fill job vacancies, but how the proliferation of online procurement services is bringing e‐business practices inside water utilities.
Treatability of Mtbe‐contaminated groundwater by Ozone and Peroxone
Authors: Liang Sun , Yates Richard S. , Davis Dean V. , Pastor Salvador J. , Palencia Leslie S. , Bruno Jeanne‐Marie
Published: February 2018

A combination of ozone and hydrogen peroxide (known as peroxone) was studied as a treatment alternative for removing methyl tertiary butyl ether (MTBE), a common fuel oxygenate. The authors investigated the effects of oxidation of ozone and peroxone on MTBE in Santa Monica, Calif., groundwater. Experiments conducted in a large‐scale, semibatch reactor demonstrated that peroxone (at a peroxone ratio of 1.0, with applied ozone doses of ≤10 mg/L) was more consistently effective in oxidizing MTBE than was ozone alone. To achieve MTBE levels below the California secondary standard of 5 μg/L for drinking water, however, applied ozone doses of > 10 mg/L would be necessary for spiked MTBE concentrations of approximately 200 and 2,000 μg/L. Both ozone and peroxone can degrade MTBE into biodegradable products such as t‐butyl formate, t‐butyl alcohol, acetone, and aldehydes (including formaldehyde, acetaldehyde, heptaldehyde, glyoxal, and methyl glyoxal). In addition, peroxone can oxidize MTBE more rapidly than can ozone alone. When peroxone was used, the concentrations of bromate formed ranged from nondetected to 13 μg/L (in water containing ~0.3 mg/L bromide), exceeding the maximum contaminant level of 10 μg/L. Results indicated that bromate formation could be effectively controlled with hydrogen peroxide‐to‐ozone ratios > 1.0.
Mythic Monster Aids First Scientific Assessment of Nationwide Water Infrastructure Needs
Authors: Scharfenaker Mark A.
Published: February 2018

This month's column discusses the AWWA sponsored study of infrastructure needs at 20 US water utilities. Supported by the Water Industry Technical Action Fund, the study was designed and carried out by a team of consultants and members of AWWA staff and Water Utility Council (WUC) groups in cooperation with the volunteer participating utilities. The study report complements the growing body of related research by estimating the nation's projected investment needs to replace buried drinking water pipes and associated appurtenances based on a detailed examination of the actual infrastructure replacement needs at 20 large and medium‐size US water utilities. Cost projections are given, along with study recommendations, and lists of participating utilities and contributors.
Putting the Source Water Puzzle Together
Authors: Bruning Sheila
Published: February 2018

This article uses a case study to illustrate how to develop a source water protection plan. The West Bonner Water District was involved in a proposed land swap a decade ago which started it down the road of developing a source water protection plan. The article describes how the district is still working today to get stringent land use regulations approved.
PRACTICAL GUIDELINES FOR Maintaining distribution system WATER QUALITY
Authors: Kirmeyer Gregory J. , Friedman Melinda , Martel Katherine D. , Noran Paul F. , Smith Darrell
Published: February 2018

This article provides a simple and practical five‐step process to optimize water quality from distribution systems to the tap. These five steps include: understand your distribution system, and define the problems; set water quality goals, and establish preliminary performance objectives; evaluate alternatives, and select the best approach; implement good management practices, and monitor effectiveness; and, finalize performance standards, and develop standard operating procedures. Best management practices are presented for utility operations and key guidelines and recommendations from the AWWA Research Foundation are summarized.
Improving Chemical Handling Procedures Can Help Reduce Associated Treatment Problems
Authors: Casale Robin J.
Published: February 2018

Contamination of drinking water treatment chemicals, the presence of foreign matter, and delivery problems can affect drinking water quality, treatment plant reliability, regulatory compliance, and residual handling and disposal practices. A survey was conducted of the groundwater and surface water facilities of the American Water Works Company Inc. as they pertained to treatment chemicals. The goal of this study was to detail treatment chemical issues and identify areas for improvement that will reduce the consequences associated with treatment chemical problems. The application of simple procedural recommendations in the areas of treatment chemical inventory, chemical bid specification, pre‐unloading procedures and testing, and periodic specialty testing can all help improve the reliability of service and the quality of drinking water.
Trend Beat
Authors: Parmelee Mary A.
Published: February 2018

Topics covered in this column include: new regulations being applied to the disinfection of drinking water may lead to an increase in the adoption of ultraviolet disinfection as a water treatment solution; the Ngau Tam Mei water treatment facility in Hong Kong is the first water treatment plant in the world to use dual‐stage biological filtration with granular activated carbon to remove ammonia, replacing breakpoint chlorination; a survey by the Construction Industry Manufacturers Association (CIMA) that indicates that most construction equipment makers will soon be expanding the capabilities of their websites to provide more online support to their dealers, customers, and suppliers, including transactional capabilities; and, the incidence of repeated attacks of internet worms and viruses are becoming a cost of business for everyone connected to the web and making it difficult for information technology specialists to keep up with all the patches and fixes to protect their networks.
Resolve
Authors: Hoffbuhr Jack W.
Published: February 2018

In his column, AWWA Executive Director Jack Hoffbuhr writes about his feeling of resolve, stemming from the September 11, 2001 terrorist attacks, to protect public health regardless of the obstacles or challenges and not allow it to be compromised by criminals. He talks about how our public water systems are vulnerable because of our commitment to freedom and information, and asks the question of what is the proper balance between public communications and security.
Using Genetic Algorithms to Rehabilitate Distribution Systems
Authors: Wu Zheng Y. , Boulos Paul F. , Orr Chun Hou , Ro Jun Je
Published: February 2018

Many US water supply infrastructure systems are nearly 100 years old. Where as some are working nearly as efficiently as when they were first installed, others are showing their age with clogging, leaks, breaks, and service disruptions. To pinpoint the best solutions for each particular project, past practices often involved a tedious trial‐and‐evaluation procedure that seldom led to the most effective or most economical solutions for upgrading pipe networks. Because these upgrades and modifications are usually very expensive, it is imperative that sound analytical procedures are used to select economical design and rehabilitation alternatives. The fast messy genetic algorithm (fmGA), based on outcomes seen in nature, automatically determines low‐cost design rehabilitation and expansion alternatives that best meet prescribed system performance criteria. This methodology helps water utilities streamline their network rehabilitation and capital expenditure requirements and determine facility sizing and timing for system enhancements and expansions. This optimization procedure is a variation of the GA, a popular intelligent search procedure based on the mechanics of natural selection and evolution. The hydraulic simulation is performed using an extended version of the EPANET water distribution network solver. It selects least‐cost improvement alternatives that satisfy designated constraints on the network hydraulic performance for any given range of demand loading and operating conditions. This research compared outcomes using the fmGA method with three water distribution system examples taken from the literature. The fmGA found cost‐effective solutions much more quickly than the previously used analytical methods.
Gaining funding support FOR INFRASTRUCTURE PROGRAMS
Authors: Spacek James , Matichich Mike
Published: February 2018

This article presents a case study to illustrate how Portsmouth, Virginia, with portions of water infrastructure dating back to the late 1800s, used water utility management, operations, financial planning, and public relations to deal with its own infrastructure challenge. Even though confronted with extensive city redevelopment, a declining population, loss of jobs, and a limited tax base, the city managed to rally the support of its local government and citizens to raise rates and tackle a backlog of infrastructure projects. The city was successful because of its holistic, interactive, optimized, and well‐communicated approach. As the authors point out, an infrastructure revitalization plan must be consistent with a city's overall goals and objectives, recognize rehabilitation and growth needs, include the effect of regulations, provide a long‐term financial forecasting perspective, address long‐term rates and competitiveness issues, and provide a set of tools for ongoing planning. As Portsmouth found out, such a strategic financial plan can afford a water utility and its community several direct and immediate benefits.
Chlorine Demand in disinfecting Water Mains
Authors: Haas Charles N. , Gupta Mukul , Chitluru Ravi , Burlingame Gary
Published: February 2018

The objective of this study was to determine the rate of exertion of chlorine demand in new pipes. Calcium hypochlorite, sodium hypochlorite, and dissolved gaseous chlorine were contacted with full‐size pipe sections (lined and unlined ductile iron, and polyvinyl chloride) under conditions that would be used in the disinfection of new mains. The subsequent demand and decay were measured. The process could be described by a biphasic kinetic model. The coefficients in the model could be correlated to the pipe type and diameter. From this work, a set of equations to estimate chlorine residual subsequent to main disinfection was developed.
GIS—An Alternative to As‐built Drawings
Authors: Adams Gary A.
Published: February 2018

A previous small systems helpdesk column outlined the importance of requiring as‐built plans to be part of any utility's construction projects (December 2001). This month's column outlines how a geographic information system (GIS), used in conjuction with a global positioning system (GPS), can be more reliable as an alternative to as‐builts.
In Over Our Heads? Questions on Protecting US Water Supplies
Authors: Regush Nicholas
Published: February 2018

This article discusses several questions about protecting US water supplies from terrorists and the normal everyday contamination from a variety of microbes.
Getting Involved in AWWA: Demystifying the Process
Authors: Burian Steve L.
Published: February 2018

With more than 250 councils, divisions, and working committees in which to participate at AWWA, how does an AWWA novice know where to start? We asked two young professionals (YPs) how they got involved and what advice they would have for other YPs interested in becoming a fully participating member of AWWA.
Security services, training for utilities prominent
Authors: Parmelee Mary A.
Published: February 2018

This article discusses several training and guidance materials on security measures and emergency preparedness plans for water utilities.
Water suppliers carefully watching liability suits
Authors: Scharfenaker Mark A.
Published: February 2018

The recent wave of lawsuits seeking to hold water providers liable for damages from health problems attributed to contaminants in drinking water raises the specter of yet another nascent upward pressure on water rates at a time when many utilities are fighting for funds to comply with tougher new Safe Drinking Water Act (SDWA) requirements and to upgrade security systems and aging infrastructure. Long by‐passed by such litigation in favor of the deeper pockets of corporate sources of suspect environmental toxins, suppliers of public drinking water, both public agencies and private companies, are increasingly being targeted as potentially paying parties for claimed losses associated with incidences of cancer, miscarriages, birth problems, and other maladies. This article examines several such cases that have arisen in California, New Jersey, Virginia, and Texas. No two cases are alike other than putting water utilities in a new and potentially very expensive legal arena.
Effects of Conventional Treatment on AOC and BDOC Levels
Authors: Volk Christian J. , Lechevallier Mark W.
Published: February 2018

A 12‐month assimilable organic carbon (AOC) survey of 64 conventional water treatment plants was conducted to assess mechanisms affecting effluent AOC levels. The effect of conventional treatment steps (i.e., oxidation, coagulation, filtration, disinfection) on the formation or removal of biodegradable organic matter (BOM) was also investigated at six of the sites. BOM levels were increased or decreased by various factors including the type of filter media, the type of coagulant used, and the level of watershed protection of the plant's source water. Systems that prechlorinated and used anthracite/sand filtration generally had low removal of dissolved organic carbon (DOC) and biodegradable DOC (BDOC) and increases in AOC levels through the treatment process. Systems combining prechlorination and granular activated carbon (GAC) filtration showed increases in AOC in the settled water but removal of AOC through filtration. DOC and BDOC levels were generally reduced by conventional sand/GAC filtration.
Developing and Implementing a Distribution System Flushing Program
Authors: Friedman Melinda , Kirmeyer Gregory J. , Antoun Edward
Published: February 2018

Many utilities have used flushing programs as part of distribution system maintenance, but little guidance has been available to help utilities develop programs that actively avoid water quality deterioration and meet each system's specific needs. Although flushing programs can be an important part of a good distribution system maintenance program, many utilities use them without clearly identifying water quality objectives. Secondary water quality and customer satisfaction problems can be created if adequate attention is not given to planning, implementing, and evaluating the program's effectiveness. The authors provide a rationale and guidelines for assessing current flushing programs. In addition, they provide tips that can help utilities to determine whether flushing is appropriate and to plan, implement, and manage a program. An optimized flushing program can help utilities improve distribution system water quality, reduce customer complaints, save water, enhance distribution system operation and maintenance, and better understand distribution system conditions.
Water use projections in DEVELOPING COUNTRIES
Authors: Bradley Robert M. , Weeraratne Stanley , Mediwake Tilak M. M.
Published: February 2018

As developing countries are faced with maintaining water resources and building adequate delivery systems, it is important to analyze historical data to determine actual levels of use. In many developing countries, however, records with the necessary level of detail have not been maintained. Therefore, it is especially important to account for a variety of factors that may influence usage rates. This paper explores how water use trends are specific to local conditions and how making the assumption that per‐capita rates in the United States, for example, will also be achieved in developing nations can lead to overdeveloped systems. Evidence is given regarding how many times gross estimates are made of future water demand based on assumed increase factors and ways in which these assumptions can be incorrect. This article identifies actual changes in water use over time and provides actual water use data for a range of consumer sectors to assist in planning demand. The article also examines the impact of water cost on domestic use.
Explaining the occurrence of coliforms in distribution systems
Authors: Besner Marie‐Claude , Gauthier Vincent , Servais Pierre , Camper Anne
Published: February 2018

According to the Total Coliform Rule, coliform bacteria constitute the main indicator used to detect microbial contamination in distribution systems. A major goal for water utilities is to prevent and control coliform occurrences and noncompliance (with respect to regulations). However, the applied solutions are sometimes successful only to a limited extent because of the variety of factors that may give rise to these occurrences. It is therefore important to identify those factors—from the structure and operation of the distribution system to the quality of the distributed water itself—that can influence the occurrence of coliform bacteria in a distribution system. The use of the identified factors makes the modeling of coliform occurrences attractive, and a number of approaches for doing so have recently been proposed. This article provides a review that includes the mechanisms of how coliform bacteria are introduced into treated and distributed drinking waters, the major factors controlling the survival and regrowth of coliforms once introduced into the system, and the modeling efforts carried out to explain or predict their occurrence.
Public health, security priorities pushing for better water quality monitoring
Authors: Parmelee Mary A.
Published: February 2018

This article discusses how the development and widespread use of sophisticated, continuous, real‐time water quality monitoring have become more urgent for water suppliers as they try to protect against waterborne pathogens and organic‐waste contaminants and against more vague but disturbing concerns about bioterrorism.
Using chlorine demand TO PREDICT TTHM and HAA9 formation
Authors: Gang Daniel Dianchen , Segar Robert L. , Clevenger Thomas E. , Banerji Shankha K.
Published: February 2018

Because of an increasing need to balance health risks for pathogen control and disinfection by‐product (DBP) formation in water supplies, utilities are forced to closely examine and optimize their disinfection practices. The authors provide a simple mechanistic model to predict total trihalomethane (TTHM) and the sum of nine haloacetic acids (HAA9) formation based on chlorine demand. To evaluate this modeling approach, eight Missouri surface waters (raw and alum‐treated) were used in DBP formation and chlorine decay kinetic studies. A parallel first‐order reaction model was used to fit the chlorine decay data, and the model coefficients were used to predict THM and HAA formation. Yield coefficients for TTHMs and HAA9 were obtained from fitting the DBP kinetic data. On average, the TTHM and HAA9 yield coefficients for all raw surface waters tested were about 40 μg TTHM/mg Cl2 and 25 μg HAA9/mg Cl2 consumed, respectively. In waters subjected to alum coagulation, the average TTHM and HAA9 yield coefficients were 30 μg TTHM/mg Cl2 and 17 μg HAA9/mg Cl2 consumed, respectively. The DBP predictive model introduced in this study provided a simple, reliable basis to evaluate treatment options by focusing on chlorine demand. This model can be readily calibrated to local conditions.
Measuring oxidant species in ELECTROLYZED salt brine solutions
Authors: Gordon Gilbert , Bolden Renee , Emmert Gary
Published: February 2018

The electrolysis of salt brine solutions by onsite generators produces chlorine (free available chlorine [FAC = Cl2, HOCl, and OCl–]) at concentrations ranging from 200 to 1,000 mg/L. There is some speculation that the electrolysis of salt brine also produces chlorine dioxide (ClO2) and ozone (O3). The analytical methods frequently cited for measuring ClO2 and O3 in anolyte liquors following salt brine electrolysis are the DPD and indigotrisulfonate methods. These analytical procedures are routinely used to measure drinking water residuals in finished water. However, when used for measuring components in electrolysis cell liquors, false‐positive results are observed.
Taking Stock
Authors: Hoffbuhr Jack W.
Published: February 2018

In his column, AWWA Executive Director Jack Hoffbuhr offers a discussion of several questions as a means of taking stock of ourselves that include: is my view of the world out‐of‐date; am I prepared to spend 20% of my time to stay up‐to‐date; and, am I prepared to be on the leading edge of change? He stresses the importance of periodically taking stock of ourselves in order to develop personally within our organizations and, in turn, help our organizations develop.
Toxicity of chlorine and three nonoxidizing molluscicides to the pest mussel Limnoperna fortunei
Authors: Cataldo Daniel , Boltovskoy Demetrio , Pose Monica
Published: February 2018

The freshwater Asiatic mussel Limnoperna fortunei invaded the Paraná–Uruguay river system in Argentina around 1990. Since then, the pest mussel has spread extensively and is now a major nuisance for many industrial and domiciliary water supply systems. This research exposed L. fortunei adults to chlorine and three nonoxidizing commercial molluscicides for varying amounts of time at concentrations between 0.25 and 100 mg/L at 15, 20, and 25°C. At 25°C, chlorine was effective at all concentrations (1–100 mg/L) yielding 100% mortalities in 11–17 days. At 15 and 20°C, only concentrations ≥ 5 mg/L resulted in total kills after three to six weeks of exposure. The first molluscicide had little effect at 1 mg/L at all temperatures, but 2.5 mg/L of the molluscicide at 20 and 25°C attained 80–90% mortalities on the third day of postexposure. At 15°C, the second molluscicide failed to kill 100% of the mussels exposed at all concentrations tested. At 20°C, only doses > 10 mg/L eliminated all the mollusks, but at 25°C, all concentrations of the molluscicide down to 2.5 mg/L were 100% effective in one week or less. The third molluscicide proved to be the most toxic of the compounds tested, yielding > 50% mortalities at all temperatures at ≥ 1 mg/L. At higher temperatures, toxicity was substantially enhanced for all toxicants, especially chlorine.
Differences in coagulation efficiencies between PACl and PICl
Authors: Wang Dongsheng , Luan Zaokun , Tang Hongxiao
Published: February 2018

Laboratory preformed inorganic polymer flocculants—polyaluminum chloride (PACl) and polyiron chloride (PICl)—were compared for their coagulation efficiency according to various basicity (B) values. Conventional jar tests were combined with electrophoretic mobility (EM) measurements. After dosing, some preliminary experiments were also carried out on coagulant speciation analysis by ferron assay. The results show fundamental differences in coagulation between PACl and PICl. Basicity has a significant effect on coagulation behavior. Particle destabilization efficiency and charge neutralization ability, as shown by the effect of dosage on residual turbidity (RT) and EM, increases for PACl but decreases for PICl as their basicities are raised. A coagulation‐stability diagram, showing the quantitative relationship between the change in zeta potential and the coagulating species, is plotted to more clearly illustrate the differences between PACl and PICl. Differences between the mechanisms of coagulation for PACl and PICl are also discussed. Suggestions for further development of inorganic polymer flocculants are proposed.
Discussion: “Predicted Public Health Consequences of Body‐contact Recreation on a Potable Water Reservoir”
Authors: Soller Jeffrey , Olivieri Adam , Eisenberg Joe , Spear Robert , Tchobanoglous George
Published: February 2018

In the May 2002 issue of Journal AWWA, Stewart and co‐workers summarized an investigation that addresses the potential health consequences related to consuming water from a reservoir at which body‐contact recreation is permitted (Stewart et al, 2002). The investigation used a water quality model to estimate pathogen loading from recreationists and to calculate predicted pathogen concentrations at the outlet tower of the reservoir. Based on those data, risk to drinking water consumers was predicted. The authors reported that the annual risk of waterborne illness would increase three times above background, despite conventional water treatment before distribution as potable water. Although the authors used a powerful combination of modeling techniques for assimilating a wide range of disparate data, the substantial uncertainty associated with the model parameters most directly affecting risk is not articulated and/or analyzed in the findings of the investigation. The unspecified effect of uncertainty in this investigation casts doubts on the conclusions. These uncertainty issues, furthermore, suggest that the use of the Stewart et al document as guidance for policymakers and stakeholders who are examining issues associated with body‐contact recreation and drinking water should be reexamined. The authors raised the fact that high levels of uncertainty may affect the analysis. They report: “The model was highly sensitive to parameters associated with pathogen loading” (page 87). Pathogen loading to the reservoir was assumed to occur in two ways: shedding of residual fecal material from recreationists' bodies upon contact with the water (shedding); and, accidental fecal releases (AFRs) and therefore was computed as a function of the number of infected individuals recreating in the reservoir. The percentages of recreationists assumed to be infected in each simulation varied by pathogen as follows: Cryptosporidium 0‐5% , rotavirus 5‐20%, Giardia 0‐10%, and poliovirus 5‐20%, and the frequency of an AFR was 0‐0.2%. This discussion focuses on parameter estimates for Cryptosporidium prevalence, rotavirus prevalence, and AFRs as well as the risk management implications of those ranges.
Outsourced training helps utility fill code compliance need
Authors: Marquez Don
Published: February 2018

The Denver Water Department (DWD) needed to prepare employees to pass the National Electrical Code (NEC) exams. This article describes how the utility created a quick and inexpensive training program that would not interfere with the section's operating functions.
Needs and Tools for Water System Data Management
Authors: Cockriel Robert , Auge Jerry , Martini Dave
Published: February 2018

This data management case report studied three Minnesota utilities, focusing on data management for water systems. The cities of Bloomington, Shoreview, and Saint Peter were chosen because of their varying size, system complexities, and resources. The study analyzed the complexities of compiling and managing the data sets associated with public infrastructure and the current methods of collecting, storing, retrieving, and updating infrastructure data. It also provided recommendations on how best to manage the data, improve efficiency, and meet the current and future customer expectations on an individual basis. The recommendations incorporated field‐based computing to complement or replace existing methods of gathering and manipulating infrastructure‐related data and accessing systems records. Various strategies and methods were evaluated on their ability to provide an efficient and systematic maintenance approach, increase customer satisfaction, respond more quickly to emergencies, and provide increased budgeting control.
Full‐Scale Assessment of waste filter backwash recycle
Authors: Tobiason John E. , Edzwald James K. , Levesque Benjamin R. , Kaminski Gary K. , Dunn Howard J. , Galant Peter B.
Published: February 2018

This article provides the results of studies of full‐scale waste filter backwash water (FBW) recycle practices and water quality effects at six water treatment plants as well as recommendations for evaluating FBW recycle practices. Water quality parameters assessed included suspended solids, turbidity, particle counts, total and dissolved organic carbon, aluminum, and manganese. Results showed insignificant effects on plant influent water quality for recycle of clarified FBW and for a plant with continuous recycle. The FBW recycle quality was highly temporally variable for plants with only flow equalization (no solids removal), exhibiting significant peaks in solids levels that caused significant short‐term increases in plant influent turbidity. However, the performance of downstream clarification (dissolved‐air flotation or plate sedimentation) and filtration were not affected by FBW recycle for these plants. Evaluation of recycle effects requires knowledge of the site‐specific details of plant operation (generation of recycle streams, flow control) and the chemistry of process waters (raw, recycle, and coagulated).
Emerging Water Quality Issues Committee predicts possible future concerns and assesses potential solutions
Authors: Hunsinger Ron
Published: February 2018

This article discusses the Emerging Water Quality Issues Committee of the Water Quality and Technology Division of AWWA. The main goal of this committee is to identify and report on emerging water quality issues that could significantly affect the drinking water industry in the future. The methods used to achieve this goal are discussed, along with the committee's structure and some of the emerging water quality issues that the committee is dealing with.
Nursery Exempt From Requirement for Well Permit
Authors: Stiegler Mayo H.
Published: February 2018

The Court of Appeals of Washington has ruled that a commercial nursery was exempt from obtaining a permit to withdraw water from a well.
Science‐based Collaboration: Finding Better Ways to Operate the Conowingo Pond
Authors: Sheer Daniel P. , Dehoff Andrew ,   The Nature Conservancy
Published: February 2018

This article discusses the Conowingo Pond Management Plan developed in 2006 by the Susquehanna River Basin Commission and the Conowingo Pond Workgroup. The plan recommended revisions to the previous operations strategy for the pond, which would provide instream flow reliability while preserving water supply reliability, energy production, and other benefits. Models and performance measures used to evaluate alternatives were developed and refined at workgroup meetings. The article details how active involvement of the stakeholders in the model development and verification lent credibility to the entire process. The collaborative process built critical shared knowledge of the lower Susquehanna system. Computer‐aided negotiation sessions where alternatives were developed and evaluated on the spot were particularly effective. The process ensured the full support of recommendations by key stakeholders.
Global Water Certification: An Important New Tool for Water Management
Authors:   The Nature Conservancy, Kaledin Jonathan C.
Published: February 2018

This article discusses the Alliance for Water Stewardship (AWS), an international collaborative of business, environmental, and social equity organizations building a voluntary “water certification program” for participants from the private, and water service provider, sectors. The goal of the AWS is to create a framework of global sustainability standards for water, housed in a permanent nonprofit organization, that can be implemented in each region of the world with the regional variability needed to make them regionally relevant. The article discusses efforts by the AWS to develop a global water certification program.
Emerging Opportunities for Public‐Private Water Partnerships
Authors: Richter Brian
Published: February 2018

This article discusses the growing water “issues” or risks encountered by businesses that rely heavily on clean water supplies to support their operations and supply chains. Some recent examples of these growing water risks for businesses are provided. The article discusses how these water risks tend to take one or both of two forms: physical and reputational. Physical risk is explained as centering on whether the company can expect to have sufficient supplies of clean water in the future to support its business. When a company's water use is causing real or perceived impacts to other parties or ecosystems, it can lead to reputational risks, affecting a company's social license to operate.
Reading, Writing, Arithmetic… and Water
Authors: Lafrance David
Published: February 2018

In his column, AWWA Executive Director David LaFrance presents several ideas for California public schools to meet the requirements of SB1413, which requires California school districts to provide access to free, fresh drinking water during meal times in school food service areas by July 1, 2011. He first computes the cost per student for purchasing free, fresh drinking water, and then presents low‐cost alternatives for making water available in cafeterias during lunchtime, including: pitchers of water or large coolers filled with water on the lunchroom tables; water bottle‐filling stations; partnering opportunities for school districts and utilities; and, donated bottled water.
Water Security e‐Tools: Greater Preparedness and Resiliency from Your Desktop
Authors: Travers David
Published: February 2018

This article discusses an effort by the U.S. Environmental Protection Agency (USEPA) to support protective programs at water utilities by developing or updating several water security e‐tools that are listed in the article. The benefits of USEPA water security e‐Tools are presented, along with training and exercise tools developed by the USEPA to assist the water sector in developing and conducting water security training and exercises.
Supply Risk and the Bond Market
Authors: Lafrance David
Published: February 2018

In his column, AWWA Executive Director David LaFrance discusses a report titled “The Ripple Effect: Water Risk in the Municipal Bond Market,” published by Ceres, an investor and environmentalist group. The report focuses on the relationship of water supply vulnerability and bond ratings and, among other things, is critical of bond rating agencies, saying they don't adequately evaluate water scarcity when assessing municipal water utilities. LaFrance argues that bond rating agencies don't evaluate supply risk in the same way as Ceres, and he discusses a host of other variables evaluated by bond rating agencies when they determine a utility's bond rating.
Review of biologically active filters in drinking water applications
Authors: Zhu Ivan X. , Getting Tom , Bruce Dan
Published: February 2018

Biological water treatment processes are based on the growth of microbial communities capable of metabolizing contaminants through mediating oxidation–reduction reactions. Biologically active filters (BAFs) are applied in drinking water treatment for the removal of contaminants including natural organic matter, nitrate, trace organic compounds, perchlorate, sulfate, iron, and manganese. BAFs make use of a fixed film that develops on media such as sand, anthracite, granular activated carbon, or membranes. This biofilm is a diverse community, but the conventional biological treatment process basically takes a “black box” approach with respect to microbial community development. Controlling biofilm thickness and producing microbial communities fully adapted to target contaminants represent significant engineering challenges. This article discusses the advantages and applications of BAFs to remove contaminants in drinking water sources, reviews microbial communities in bulk water and biofilms, and summarizes the current fundamental knowledge about biofilm adhesion and control.
Effect of cleaning protocol on membrane permeability recovery: A sensitivity analysis
Authors: Porcelli Nicandro , Judd Simon
Published: February 2018

Results are presented for a four‐year study of chemical cleaning of ultrafiltration/microfiltration membranes for inland potable water treatment are presented. The study made use of a bespoke test cell in which sample membrane fibers extracted from modules in full‐scale operating membrane plants were examined. The test entailed cleaning—with the reagents used at each of the nine sites—under controlled conditions of reagent concentration (C), soak period (P), and temperature (T). Data were analyzed using a standard response surface model to identify optimum cleaning protocol parameter values. Results showed the effect and order of importance ofC, P, andTto vary both between sites and temporally, making identification of the most appropriate prescriptive cleaning protocols extremely challenging. Optimization of plant operation and maintenance requires methods for recording and tracking changes in cleaning efficacy, such as the one used in this study, as an adjunct to assessing the tendency for initial fouling through pilot‐testing.
DC Looks Ahead
Authors: Curtis Tom , Roberson J. Alan
Published: February 2018

This month's column looks at four major areas addressed in 2010: legislative, infrastructure finance, security and preparedness, and regulatory.
New Year's Resolutions…
Authors: Lafrance David
Published: February 2018

In his column, AWWA Executive Director David LaFrance discusses how utilities balance the use of reserves, debt, and rates. As a new year's resolution, LaFrance offers the following: in 2011 we should resolve to increase the public's understanding of the importance of maintaining a strong, reliable water system as well as to educate them about the fact that the cost of doing so is and will continue to be on the increase. We should also wean ourselves off the use of reserves for meeting our costs and restore water rates to a level at which they reflect the cost of providing the service.