bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Affecting Drinking Water Biofiltration
Authors: Liu Xibo , Huck Peter M. , Slawson Robin M.
Published: February 2018

This research examined several important factors affecting the removal of biodegradable organic matter in drinking water biofilters. Laboratory‐scale biofilters were used and were fed a cocktail of easily biodegradable compounds. The factors investigated were chlorine or chloramine in the backwash water, air scour during backwashing, anthracite/sand versus granular activated carbon (GAC)/sand media, and low (5°C) versus high (20°C) temperature operation. Factorial design experiments showed that the three main factors (chlorine in the backwash water, temperature, and media type) and their interactions were significant in most cases. The temperature effect was more significant when chlorine was present. The GAC filters were much more resistant to chlorinated backwash water than were anthracite filters. Air‐scour effects were generally negligible except in some cases at low temperature with chloramine in the backwash water. Glyoxal removal was more sensitive to unfavorable biofiltration conditions than were removals of acetate, formate, and formaldehyde.
Natural salt pollution control IN THE SOUTHWEST
Authors: Wurbs Ralph A.
Published: February 2018

Natural salt pollution severely constrains development and use of water supplies in several major river basins in the Southwest. Federal, state, regional, and local water management agencies continue to investigate and implement measures to prevent salts from entering the rivers, remove salts from water supplies, and otherwise deal with excessive salinity. This article provides a general overview of natural salt pollution in the Permian Basin Region as well as studies and projects dealing with its control or mitigation.
Microfiltration Plant Meets Water Regulations and Community Approval
Authors: Santa Andrea L. , Evans Rulison
Published: February 2018

The Pittsburgh Water and Sewer Authority (PWSA) owns and operates the existing 120 mil gal (452 ML) open reservoir in Highland Park, known as Highland Reservoir 1. It provides drinking water for approximately 50% of Pittsburgh's residents. In 1984, changes in drinking water regulations required public water suppliers in Pennsylvania to cover, abandon, or otherwise protect open potable water reservoirs from potential contamination. This article describes how PWSA resolved the issue, under intense public and political scrutiny, by building a new microfiltration plant housed in a small and attractive nineteenth century‐style building that integrates well with the park atmosphere and the surrounding community. The process used by the engineering consultant to pilot‐test for the ideal treatment process is discussed.
As removal using ion exchange with Spent Brine Recycling
Authors: Clifford Dennis A. , Ghurye Ganesh L. , Tripp Anthony R.
Published: February 2018

A conventional sulfate‐selective Type‐2 polystyrene strong base anion resin was studied for arsenic (As) removal from Albuquerque, N.M., drinking water. Attention was focused on the regeneration aspects of ion exchange and the potential for reusing the spent brine directly without removing As. The major finding was that As‐laden spent brine with makeup salt addition to 1 M chloride could be reused up to 20 times with no effect on As leakage and minimal effect on run length. The authors also found that As could be removed from the spent recycle brine using ferric hydroxide coagulation in such a way that the resulting sludge passed the toxicity characteristic leaching procedure test as a nonhazardous waste.
Key Trends and Market Developments in the Water Industry
Authors: Maxwell Steve
Published: February 2018

This article discusses ten critical trends or key drivers in the water industry that will shape the industry in the future.
LT1ESWTR—16 Months to Go ... and Counting
Authors: Grimm Mike
Published: February 2018

This article discusses the new turbidity limits established by the US Environmental Protection Agency in the Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR). The article addresses the new treatment technique requirements for turbidity in combined filter effluent water and discusses how exceeding the turbidity levels can trigger an investigation. The benefits of using a supervisory control and data acquisition (SCADA) system even for small water systems are discussed.
Introducing the Disinfection Systems Committee
Authors: Crozes Gil
Published: February 2018

This article describes the AWWA Disinfection Systems Committee's focus on understanding and communicating regulation changes to the AWWA membership, and how those changes have driven new disinfection technology. Because of its broad focus, the Committee maintains active liaisons with other Water Quality and Technology Division (WQTD) committees for concerted actions, and works with other Technical and Educational Council (TEC) divisions, the Standards Council, and the Water Utility Council. The Committee's membership has traditionally represented a cross‐section of the industry including academia, the manufacturing industry, drinking water utilities, regulatory agencies, and consultants. The article discusses the areas of water quality that the Committee focuses on and lists the various means by which the Committee disseminates information and education.
Work/Asset Management Central To GCWW's Business Transformation
Authors: Rager David
Published: February 2018

This article discusses some tough decisions made by Greater Cincinnati Water Works (GCWW) for transforming the utility to not only prosper, but to continue to offer the highest‐quality water to its consumers. Management drafted a technology migration master plan that included both Windows NT and Unix servers running on a Windows NT network and using an Oracle database so that as these systems were built they could be linked together. Management also developed a strategic business plan that allowed the utility to function more like a business enterprise. The article discusses four main foundational areas that the business plan focused: creating a single point of customer contact; automating the geographic information system (GIS); using a process control system to monitor assets and water quality; and, connecting everything together through work order management.
Abilene Solves Supply Problem With Microfiltration
Authors: Hutchins Kenny , Schaefer James
Published: February 2018

This report discusses how the city of Abilene, Texas, augmented its water supply with brackish water from a reservoir that required an advanced treatment process to achieve acceptable finished water total dissolved solids (TDS) levels. The pipeline and pumping station plans also included a new 8 mgd water treatment plant that would be expandable to 24 mgd. Reverse osmosis (RO) was chosen as the treatment process with microfiltration (MF)/ultrafiltration as the pretreatment process. The city of Abiliene decided that coagulation upstream of MF was the best approach to reducing color and dissolved organics and would improve the RO performance. The article describes how the pilot testing was conducted in four phases, and how the decision of using direct coagulation meant less initial investment and lower labor and maintenance costs down the road.
Facility Protection: A Step‐by‐step Process
Authors: Kimmons Rob L.
Published: February 2018

This article discusses several procedures for increasing security at facilities that include pre‐employment screening, employee training sessions, vulnerability assessments and emergency response plans, establishing relationships with local law enforcement and fire protection services, security hardware, proper maintenance, and key control.
Resolutions
Authors: Hoffbuhr Jack W.
Published: February 2018

In his column, AWWA Executive Director Jack Hoffbuhr discusses two topics: providing the best customer service possible, and participating actively in AWWA and encouraging others to do the same. He stresses the importance of making customer service part of the culture of the organization, not just words in a slogan or on the company letterhead. Secondly, he states two important reasons for being actively involved in AWWA: it sharpens your own skills, thus allowing you to grow professionally and build relationships that will advance your career; and, sharing with others your own knowledge, expertise, and experience.
Water interests gird for round two of MTBE safe harbor fight
Authors: Scharfenaker Mark
Published: February 2018

This article discusses several bills in the U.S. Congress, including: HR 6, a comprehensive energy policy bill that includes language concerning the controversial MTBE safe harbor, which AWWA strongly opposes; HR1560, the Water Quality Financing Act that would reauthorize and reform the Clean Water Act state revolving fund (SRF) program for wastewater utilities by closing an estimated $10 billion annual funding gap that exists between infrastructure needs and current levels of spending; HR866, the Wastewater Treatment Works Security Act that would provide $200 million in grants to underwrite 75% of the cost of developing vulnerability assessments and implementing security improvements at wastewater treatment works, up to a maximum of $150,000 per plant; and, S 994 that orders operators of nonfederal facilities that make, distribute, or use hazardous chemicals to complete vulnerability assessments and site security plans and to consider (but not require) use of safer practices such as using less hazardous substances to do the same job.
Adapting GASB 34 for Water Utility Rate‐Making
Authors: Mumm Jason , Matthews Paul
Published: February 2018

When the General Accounting Standards Board issued Statement No. 34 in 1999, many utility managers thought it meant big changes to their water rate‐making principles and financial reporting requirements. However, GASB 34 does not change these principles. Although it puts forth new reporting standards and definitions, AWWA Manual M1 remains the preeminent guide for water utility ratemaking, regardless of the accounting rules presented by GASB 34. This article helps eliminate some of the confusion surrounding GASB 34 and its relationship to rate‐making.
Oxymorons
Authors: Hoffbuhr Jack W.
Published: February 2018

In his column, AWWA Executive Director Jack Hoffbuhr discusses the oxymoron “congressional wisdom” as it relates to the recent issue of MTBE safe harbor included in the Omnibus Energy Bill presented to Congress. He describes how a coalition formed by AWWA to campaign against this provision, was successful in forming a filibuster against it.
Effect of Addition Sequence on Dual‐Coagulant Performance
Authors: Ammary Bashaar Y. , Cleasby John L.
Published: February 2018

This research investigated the effect of addition sequence of cationic polymers in combination with inorganic coagulants on flocculation kinetics. A photometric dispersion analyzer (PDA) was used as the primary device to study the flocculation kinetics of kaolin clay suspensions at different concentrations and under different experimental conditions in a batch reactor. An automatic image analyzer was used in a limited number of experiments to reinforce the results obtained by the PDA. Zeta potential and residual turbidities were also measured. Results indicated that when cationic polymers are to be used with ferric inorganic coagulants, they should be added simultaneously or at the same place in water treatment plants. Simultaneous addition of coagulants produced higher flocculation index values at the end of rapid‐mixing time, suggesting a higher rate of particle growth, as well as higher resistance to shear induced by extended rapid‐mixing periods. This affected the entire flocculation period and produced lower residual turbidity values. The authors hypothesized that the improved performance produced by simultaneous addition is attributable to the matrix of the first flocculi formed in the presence of both the cationic polymer and ferric hydrolysis products.
13 Ways to Make the Strategic Planning Process More Useful
Authors: Maxwell Steve
Published: February 2018

This article discusses key guidelines to developing a truly useful and sustainable strategic planning process that include: plan the planning process; strategic timing is pivotal; make sure the right people are involved; top management must lead and champion the process; make sure the data you're using are as accurate and timely as possible; be as specific as possible in the delineation of your goals; objectives and goals should be ambitious, but realistically achievable; know exactly who's doing what by when; recognize you're probably not going to accomplish everything; consider outside help; quantity does not equal quality; get the word out to all employees; and, a strategic plan is never finished.
Utilities Pull no Punches in LT2ESWTR Comments
Authors: Scharfenaker Mark
Published: February 2018

This article discusses comments made by leading water utility members related to the Long Term 2 Enhanced Surface Water Rule (LT2ESWTR). The comments came from utility organizations such as AWWA, the Association of Metropolitan Water Agencies (AMWA), the National Association of Water Companies (NAWC), and the National Rural Water Association. The organizations are concerned that some monitoring requirements are unnecessarily inflexible and punitive and that the proposal inappropriately pushes ultraviolet (UV) disinfection to the exclusion of other treatment alternatives to achieve additional Cryptosporidium treatment credit. The article does not describe the details of the proposed LT2ESWTR.
How to Talk to Your Customers
Authors: Wisely‐Cribbins Melissa T.
Published: February 2018

This article discusses a few simple suggestions for improving communications between a utility and its customers that include: know to whom you are talking; answer customers' questions to the best of your ability; and, drop the industry jargon and acronyms.
Setting Water Allocation and Withdrawal Policy
Authors: Falcone William D.
Published: February 2018

The New England Section of AWWA (NEWWA) has made public water supply a clear priority. Faced by a range of water allocation and withdrawal issues, NEWWA began developing policy recommendations for consideration by water systems, federal regulators, and state authorities. The section's Water Resources Committee (WRC) was charged with reviewing water allocation policies and procedures in the six‐state region of Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. After more than a year of work, the WRC developed a regulatory screening matrix and white paper on water supply permitting delays and instream flow‐setting policies. Early in 2003, the NEWWA Board of Directors adopted the policy derived from the WRC report. The policy comprises seven areas related to water supply allocation: allocation priority; supply management; storage, interconnection, and transfer; identification of future sources of water supply and development of redundant supplies; conservation and drought; funding; and, water supplier input. As part of its policy, NEWWA also developed recommendations for implementing measures in each area. According to NEWWA, the prime priority for water allocation is meeting the public's drinking water, culinary, safe and healthy transportation of waste material, and fire protection needs. Water providers must be stewards of their water sources and use their supplies as efficiently as possible. The water supply community should partner with the US Environmental Protection Agency, state regulators, and local agencies to secure sufficient supply for future needs. To facilitate this goal, permitting processes need to be streamlined and the regulatory burden eased. Above all, water suppliers must not take a backseat while others formulate water allocation and withdrawal policy that will affect utilities' ability to meet consumer needs.
Modeling for Hydraulic Capacity
Authors: Boxall J.B. , Saul A.J. , Skipworth P.J.
Published: February 2018

Pipes in distribution systems often become tuberculated because of internal corrosion, sliming, and scaling. This condition frequently leads to an increase in the roughness of the pipe wall and in a reduction of the pipe diameter. Such changes lead to reduced hydraulic capacity of the pipes within distribution systems. Most model calibration is undertaken by adjusting roughness coefficients alone; the reduction in pipe diameter is often neglected. This may have a significant effect on the prediction of the correct flow velocity. The calibrated models often correctly predict the pressure distribution and the flow balance at each node in the system; however, the representation of the flow paths and velocity distribution may not be well predicted. As a consequence, the prediction of the travel time may be inaccurate. Water age is a function of the travel time, and water age is known to have a significant effect on water quality and on the way in which water quality changes within distribution systems. This article describes the relationship between pipe roughness and effective pipe diameter based on a series of fieldwork measurements and a modeling study. On the basis of the system studied, it is shown that to accurately model measured pressure response, flow, and velocity, an increase in effective roughness height of 1 mm (0.04 in.) is equivalent to a 2‐mm (0.08 in.) reduction in effective diameter. Therefore, the change in diameter caused by turberculation of the pipe wall is an important parameter, and such changes, together with changes in roughness, should be taken into account in any mathematical model, particularly those in which consideration is given to water quality.
S2D/DBPR Strays from Agreement, Utilities Say
Authors: Scharfenaker Mark
Published: February 2018

This article discusses how dozens of leading water supply industry professionals have stated that the Stage 2 Disinfectants/Disinfection Byproducts Rule (S2D/DBPR), proposed last August by the U.S. Environmental Protection Agency (USEPA), strays beyond the justifiable objective of a negotiated rulemaking agreement to ensure equitable systemwide control of DBPs. The article states that these professionals assert that the USEPA did not aim to enhance Stage 1 Disinfectants/Disinfection Byproducts Rule (S1D/DBPR) protections to prevent delivery of elevated DBP concentrations to some water system customers. Instead, based on suspected cancer risks associated with chronic exposure, the USEPA has wrongly rationalized the rule as a step toward controlling reproductive and development risks that may be associated with short‐term exposures.
Drug Residuals: How Xenobiotics can Affect Water Supply Sources
Authors: Ongerth Jerry E. , Khan Stuart
Published: February 2018

This article presents an approach to describing the presence of measurable pharmaceutical residuals originating in municipal sewage, which in turn provides a means of predicting the likely appearance of individual contaminants in effluents and downstream water sources. Trace organic contaminants come from many sources in wastewater. Their health significance is unknown and a problem for toxicologists to define. Analytical technology now enables measurement of many organic contaminants at very low concentrations and for which no adequate understanding of health significance has been developed. The study was conducted to show how a class of contaminants (pharmaceutical residuals) can be described and to demonstrate the presence of unmeasurable residuals. Regulators will increasingly be faced with pressure to assure safety without a clear toxicological basis for measuring risk. This work provides a blueprint for describing the presence and distribution of other groups of trace organic contaminants. It also underscores the urgent need for development of fundamental toxicological principles for assessing potential significance to human health from exposure to trace and ultratrace contaminants and mixtures.
Banishing the Specter
Authors: Offbuhr Jackw . H
Published: February 2018

In his column, AWWA Executive Director Jack Hoffbuhr discusses waterborne disease. He mentions that the United Nations has proclaimed that the decade from 2005 to 2015 will be the “International Decade for Action, Water for Life,” with the overall goal being to cut in half, by 2015, the number of people who are unable to access safe drinking water and basic sanitation. He believes it can be done and discusses three major weaknesses that need to be overcome first.
Not Providing Notice of Wetlands Designation Does Not Violate Due Process
Authors: Stiegler Mayo H.
Published: February 2018

The Court of Appeals of New York has determined that a failure to provide a landowner in the state with actual notice that his property was within the boundaries of wetlands did not deprive the landowner of the due process of law.
Orange County's innovative water project to purify 70 mgd in 2007
Authors: Guendert Dawn
Published: February 2018

This report presents the Groundwater Replenishment System (GWRS), used by the Orange County Water District (OCWD) in southern California, as an example of how integrated membrane technology (microfiltration and reverse osmosis) can be used to supply a new, cost‐effective and reliable source of water. The article describes how GWRS uses a combination of advanced water purification technologies (MF, RO and ultraviolet light) with hydrogen peroxide to purify secondary wastewater to a level of quality similar to bottled water, which is well beyond drinking water standards. Instead of being discharged directly into the ocean, the treated effluent will either be injected into a seawater intrusion barrier along the coast or percolated in ponds near the Santa Ana River to recharge Orange County's groundwater basin, thus providing another option for managing effluent discharge to the ocean during periods of wet weather.
Hindsight Is 20/20: Using History to Avoid Waterborne Disease Outbreaks
Authors: Logsdon Gary S. , Schneider Orren D. , Budd George C.
Published: February 2018

Despite strenuous efforts to prevent them, waterborne disease outbreaks continue to occur from time to time in countries that have the knowledge and capability to prevent them. This article presents the concept that multiple adverse events or changes can often be associated with waterborne disease outbreaks. The information in this article is designed to encourage water treatment plant operators, water quality supervisors, and plant managers to maintain vigilance at all times so circumstances that might lead to a treatment failure and a disease outbreak can be avoided. The authors discuss the importance of water treatment plant personnel being alert at all times and remaining watchful for changes in source water quality, changes in treated water quality, or both to help minimize the likelihood of future waterborne disease outbreaks.
Evaluating Water Quality Effects on UV Disinfection of MS2 Coliphage
Authors: Batch Lawrence F. , Schulz Christopher R. , Linden Karl G.
Published: February 2018

Ultraviolet (UV) disinfection is being considered for inactivation of pathogens in filtered surface waters across North America. MS2 coliphage is the most commonly used test microbe for UV reactor validation in North America, and the development of UV dose–response data for MS2 at bench scale is an integral part of validation testing. This research evaluated the effect of water quality (e.g., turbidity, particle count, particle size, and absorbance) and sample depth on inactivation of MS2 coliphage in 17 filtered waters. In addition, the inactivation performance of low‐pressure (LP) and medium‐pressure (MP) lamp types was compared. Results indicated that turbidity, particle count, and absorbance, when factored into the bench‐scale dose measurement, did not affect UV inactivation of MS2 coliphage in filtered waters meeting federal regulations. UV light from MP lamps appeared more effective than LP UV for inactivating MS2. These results suggest that water quality should not be considered a major factor in properly designed UV bench‐scale tests or in reactor validation challenges that use inactivation kinetics of MS2 coliphage as a dose‐measurement tool in filtered surface waters.
Disinfection Dawns in the Twentieth Century
Authors: Bess James W. , Malley James P. , Casson Leonard W. , Sloan Jeffrey
Published: February 2018

This article discusses disinfection, from chlorine first being used in England and the United States in the late 1890s; the use of calcium hypochlorite, sodium hypochlorite, chloramination; waterborne disease outbreaks and tighter regulations on disinfection byproducts leading to the use of chlorine dioxide, ozone, and ultraviolet light as primary disinfection technologies; and, changes in disinfection practices will be driven by water demand, pathogens, disinfection byproducts, and new technology.
Financial Focus Shifts From Controlling Operations Costs to Replacing Aging Infrastructure
Authors: Stannard William , Warmath Lex
Published: February 2018

This article discusses the changes and advancements over the last 90 years in the area of water utility finance and pricing. The article mentions how in 1914 a relatively small proportion of the nation's population was served by municipally or investor‐owned water systems, and water meters were not widely used. Customers paid flat rates that did not reflect their actual water use or property taxes. Municipally owned water systems were components of larger government functions as opposed to the independent and self‐sufficient enterprises of today. The article outlines the evolution of rate‐setting concepts, and discusses how the court case of Federal Power Commission v. Hope Natural Gas in the 1940s established the concepts of return on rate base and embedded average cost as appropriate criteria for setting utility rates. The article details how AWWA Manual M1, Water Rates, published in 1954, established a capacity‐based, cost‐of‐service approach for setting water rates, known as the “base‐extra capacity” allocation method. Then, the costs associated with the passage of the Safe Drinking Water Act in 1974 put intense pressure on water rates. System development fees were introduced in the 1980s to pay the costs associated with serving new customers. The growing need for water conservation resulted in pricing structures that provided an economic benefit to customers who limited their discretionary use of water. The 1990s introduced utility competition through privatization, and in the 21st century the focus is now on reinvestment in aging infrastructure.
Low–Level Turbidity Measurements: A Comparison of Instruments
Authors: Letterman Raymond D. , Johnson Chris E. , Viswanathan Sudhakar
Published: February 2018

The interinstrument variability of an assortment of six bench‐top and four portable turbidimeters was evaluated using four calibration materials, including user‐prepared formazin, commercial formazin, commercial stabilized formazin, and commercial suspensions of polystyrene latex microspheres. The calibration method/material, the type of light source, and the use of an instrument's ratio‐measurement feature did not have a significant effect on agreement among the instruments. However, the results divided the instruments into two groups. The instruments in group A are those that do not automatically set a predetermined reading when a sample of low‐particle (dilution) water is put in the instrument during the calibration procedure. The instruments in group B use the calibration procedure to automatically set the low‐particle reading at either zero or 0.02 ntu. Both groups include portable‐type instruments and different types of light sources. Over a turbidity range of approximately 0.01–0.5 ntu (measured by the group A instruments), the mean readings for group A instruments were about 0.1–0.3 ntu higher than those for group B.
Integrating Membrane Filtration and a Fluidized‐Bed Pellet Reactor for Hardness Removal
Authors: Li Chi‐Wang , Jian Jau‐Cheng , Liao Jung‐Chih
Published: February 2018

Fluidized‐bed pellet reactor technology was developed to remove water hardness with minimal sludge production. Operation procedures of this process include adding pellets into a column reactor and directing raw water and chemicals through the bottom of the column, keeping pellets fluidized to prevent them from being coagulated. In this study a process combining an ultrafiltration (UF) membrane with outside‐in flow configuration and a fluidized‐bed pellet reactor was proposed for hard water softening. The advantages of such a process include a compact reactor footprint, high treatment efficiency, and excellent effluent quality. Three different pellets of various sizes were used: quartz sand, beach sand, and heated iron oxide particles (HIOPs). Results show that with a removal efficiency of less than 16%, a UF membrane alone is not an effective process for removing hardness due to the slow reaction kinetic of calcium carbonate precipitation without the presence of pellets. When three types of pellets were added separately, the removal efficiency of the integrated UF/pellet process was more than 60% at a pH level of 9.0. Hardness removal efficiency improved with increasing pH and pellet surface area, and no significant membrane fouling was observed during the experiments.
Court Upholds Ordinance Requiring Water Connections
Authors: Stiegler Mayo H.
Published: February 2018

A municipal ordinance requiring homeowners to make a connection to a public water main was a valid exercise of a village's police power, according to the Appellate Court of Illinois.
What's Next for Drinking Water Security?
Authors: Roberson Alan
Published: February 2018

This article discusses how water utilities are struggling with determining what the appropriate security improvements should be at each individual facility, now that the deadline for submittal of their vulnerability assessments has come and gone. The article focuses on areas where federal government help is needed, that include: providing more detailed threat information; cost benefit analyses (CBA) tools to help prioritize security improvements; tools to evaluate the effectiveness of security improvements; and, research to develop online monitoring methods for a variety of potential contamination agents.
Darwin Calibrator—Improving Project Productivity and Model Quality for Large Water Systems
Authors: Wu Zheng Y. , Arniella Elio F. , Gianella Ernesto
Published: February 2018

This article discusses how optimization modeling provides engineers with a flexible and intelligent tool to achieve their water supply goals in the most cost‐effective manner. The article discusses a case study of using Haestad Methods' Darwin optimization technology to calibrate a water distribution model for the city of Guayaquil, Ecuador. The city hired Envirosoft and its local affiliated company Aquatec S.A. to develop an effective action plan for various tasks that included: an expansion program to manage installation of the required water and sewer connections; the design of new water and sewer networks; 30‐year master plans for the water, wastewater, and drainage systems; and, an action plan for the reduction of unaccounted‐for water. Envirosoft adopted WaterGEMS and Darwin software for hydraulic network simulation and optimization modeling. The goal of the project was to build an accurate hydraulic model of the water distribution network.
Sluice gates a critical, often‐ignored component
Authors: Niblett Dave
Published: February 2018

This article discusses the importance of sluice gates in water and wastewater systems. In many cases, these gates are the only devices in place to close off flow to and from tanks or to connect channels within a utility or system. Topics covered include: three basic reasons for gate problems; how the new composite materials with embedded steel reinforcers, such as Coplastix®, are protecting and extending the life cycle of sluice/weir gates; and, a case study involving Florida's Jacksonville Electric Authority and its use of Coplastix material in gate applications.
Committee Report: Current Perspectives on Residuals Management for Desalting Membranes
Authors:   AWWA Membrane Residuals Management Subcommittee
Published: February 2018

The use of reverse osmosis (RO), nanofiltration (NF), and electrodialysis (ED) for water treatment is expanding as water suppliers recognize the capabilities of these membranes to convert saline or poor‐quality supplies into potable water. With the increasing installation of desalination plants, however, management of residuals from these processes is a growing issue. It is also a challenging issue because of the high level of total dissolved solids and the large volume of residuals (relative to conventional treatment processes). Many regulatory agencies, utilities, and design engineers are unfamiliar with the characteristics, treatment, and disposal of desalting membrane residuals. This article provides background on the issues surrounding desalting membrane residuals and presents basic information about the desalting process and addresses residual management. Water utility managers who are considering using RO, NF, and ED for water treatment can use this report to determine methods to cost‐effectively handle, treat, and dispose of the residuals from these membranes.
Trace Contaminants in Water Treatment Chemicals: Sources and Fate
Authors: Brown Richard A. , Cornwell David A. , MacPhee Michael J.
Published: February 2018

This article describes a comprehensive national investigation of trace contaminants in water treatment chemicals. In general, no pervasive problems with trace contaminants in US water treatment chemicals were found, but serious isolated contamination incidents continue to occur. The most commonly identified problems were transport‐related, typically the result of improperly cleaned or maintained delivery vehicles and transfer hoses. These and other related problems were routinely averted when utilities developed and implemented inspection and evaluation programs for incoming chemical deliveries. This research produced compositional data from more than 50 treatment‐chemical products. Trace contaminants contributed by coagulants partitioned primarily into residuals rather than finished water during full‐ and pilot‐scale studies conducted during this investigation. Mass balance calculations from these partitioning studies confirmed the compositional data reported for coagulants in this research, results that are much lower than limited data reported previously in the literature for samples collected before 1990.
Effect of Low Turbidity and Algae on UV Disinfection Performance
Authors: Passantino Laurel , Malley James , Knudson Mark , Ward Robert , Kim Jae
Published: February 2018

It is well‐recognized that changes in ultraviolet (UV) absorbance or significant concentrations of amorphous biological wastewater solids in a water matrix can affect UV disinfection performance. However, the effects of low concentrations of drinking water particulates (turbidity) and algae on UV disinfection effectiveness are more poorly understood. This article presents the results of continuing studies at the University of New Hampshire (Durham) on the effects of particles on UV disinfection. The research was conducted in two phases of medium‐pressure UV collimated beam tests. The first phase compared the dose–response of seeded MS2 bacteriophage in waters with montmorillonite clay turbidity up to 12 ntu and algal content up to 42 μg/L as chlorophyll a (~42,000 cells/mL) to the dose–response of seeded MS2 in deionized water. The second phase compared phase 1 results with the inactivation of MS2 in the presence of naturally occurring turbidity in reservoir waters. Results indicated UV light was effective for inactivating MS2 in the presence of montmorillonite clay, algae, and naturally occurring turbidity in collimated‐beam testing.
Population Growth and Climate Change: WILL POSE TOUGH CHALLENGES FOR WATER UTILITIES
Authors: Means Edward G. , West Nicole , Patrick Roger
Published: February 2018

Over the next quarter century, water utilities in the United States will face a number of developments that will put pressure on their resources, spur them to develop alternative supplies, and necessitate new approaches to how they conduct business. This article, the second in a series, highlights two of these trends ‐ population growth and climate change. Total water management offers an approach that can equip utilities to handle both expected developments and unpredictable events. Rather than tackle issues on a local level, total water management encourages a more expansive worldview as well as cooperation and communication among communities, regulators, and institutions.
Toward a Lead‐free Public Water Supply: The Course Is Set but the Pace Must Quicken
Authors: Burlingame Gary A. , Swertfeger Jeff
Published: February 2018

This article discusses efforts toward a lead‐free public water supply. The article discusses the sources of lead and lists suggestions for action that can be taken to hasten the process of getting the lead out of our water supply by different stakeholders.
Evaluation of loose deposits in distribution systems through: unidirectional flushing
Authors: Carrière Annie , Gauthier Vincent , Desjardins Raymond , Barbeau Benoit
Published: February 2018

The objective of this project was to evaluate the extent of loose deposit accumulation in distribution systems in three Canadian cities to determine optimal flushing frequency. Unidirectional flushing was used to remove the deposits. The results obtained were found to be highly system‐dependant. The normalized mass of flushed deposits varied from less than 0.1 g/m (0.03 g/ft) to approximately 40 g/m (12 g/ft). For the range of velocities attained during flushing (0.65–2.3 m/s [2.1–7.6 fps]), the quantity of collected deposits was not a function of velocity. Analysis of the composition of the deposits confirmed the specificity of each water system. In all systems, the major fraction was iron corrosion compounds (38–72%), but organic matter (14–24%) and silicoaluminum compounds (7–16%) were also found to account for an important part of the deposits. Microbiological analyses revealed concentrations of total bacteria of approximately 1010 bacteria/g, but the presence of total coliforms was limited to 1.2% of the samples (n = 258).
Red Water Release in Drinking Water Distribution Systems
Authors: Imran Syed A. , Dietz John D. , Mutoti Ginasiyo , Taylor James S. , Randall Andrew A. , Cooper C.D.
Published: February 2018

The implementation of groundwater conservation measures has forced utilities with a historical reliance on groundwater sources to consider alternative sources to augment their supplies or to eliminate their groundwater dependence. Switching from traditional source water, however, can cause unacceptable changes in water quality that result from destabilization and the release of chemical and biological films from the interior surfaces of the existing distribution systems. Data from a two‐year study were used to identify significant water quality parameters and to develop a predictive nonlinear model to estimate the corrosivity of blends based on water quality. The results of the statistical analysis indicate that alkalinity, chlorides, sulfates, sodium, and dissolved oxygen of the source water or blend of source waters have a significant effect on release of corrosion by‐products in the form of red water. Temperature and hydraulic retention time were the significant physical and operational parameters identified.
Stae of the Industry Report 2005: A Guide for Good Health
Authors: Runge Jon , Mann John
Published: February 2018

The results are in from the second annual State of the Industry survey – a comprehensive evaluation of the water industry's overall health. The 2005 State of the Industry report presents key findings from the survey, which included the responses from more than 1,700 utility personnel, service providers, and other individuals. Like the 2004 report, this year's report helps recognize and track significant trends, identify critical and emerging issues – especially those being inadequately addressed – assess water professionals' perception of the relative health of the industry, and provide data that can help the industry prioritize programs and services. In 2005, survey respondents considered the most critical issues facing the overall water industry to be regulatory factors, business factors, source water supply, security, and water storage/ infrastructure, and they identified industry leadership as a new issue. In addition, the 2005 report includes a new look at issues broken down by key US regions and from a Canadian perspective. This year's report also identifies barriers to preparedness and provides a look at utility capital spending; it offers insight into areas of strength and weakness in today's water industry and potential future challenges. The information contained in this article can be used to give direction to the industry's current and future leaders and guide them in directing resources for the healthiest tomorrow.
Pharmaceuticals and EDCS in the US Water Industry–An Update
Authors: Snyder Erin M. , Pleus Richard C. , Snyder Shane A.
Published: February 2018

This article discusses endocrine disrupting chemicals (EDCs) and pharmaceuticals that are found in municipal wastewater treatment plant effluents and in surface waters influenced by effluents. Sources of origination and exposure, health effects on humans and aquatic life, regulations, water treatment, source water protection, risks, and ongoing research are discussed.
The Regulatory Horizon: Implications for Water Utilities
Authors: Means Edward G. , West Nicole , Patrick Roger
Published: February 2018

Regulations such as the Safe Drinking Water Act, the Clean Water Act, and the Endangered Species Act pose significant challenges for water utilities. Protecting the public health and environment means adjusting practices to limit contaminants, often detectable at levels beyond our understanding of environmental risk. This process can be costly and complex. Utilities must take steps, such as anticipating regulations and taking part in the legislative and regulatory process, to manage these challenges now and in the future. This article is the fifth in a six‐part series on trends and their implications for water utilities. It discusses present and future regulations, what they mean for water utilities, and potential management strategies to address them.
Effects of EBCT and Water Temperature on HAA Removal using BAC
Authors: Wu Hongwei , Xie Yuefeng F.
Published: February 2018

The effects of empty bed contact time (EBCT) and water temperature on the removal of haloacetic acids (HAAs) in biologically active carbon (BAC) filters were investigated. Experiments were conducted at four temperatures (4, 10, 20, and 30°C) and four EBCTs (5, 10, 15, and 20 min). The results indicated that increasing EBCT or increasing water temperature increased the HAA removal in BAC columns. To achieve an HAA removal efficiency of 50% or higher in a BAC filter, the authors suggest a 10‐min EBCT for 4°C waters and a 5‐min EBCT for waters at 10°C or higher. The kinetic analysis suggested a first‐order reaction model for HAA (except trichloroacetic acid) removal at 10°C and a zero‐order first‐order reaction model for HAA removal at 4°C. The pseudo‐first‐order reaction rate constants and half‐lives were also calculated for HAA removal at 10°C. The half‐lives—ranging from 5.9 to 17.3 min—could be used to assist water utilities in designing and operating BAC filters for HAA removal.
Katrina's True Cost
Authors: Hoffbuhr Jack W.
Published: February 2018

In his column, AWWA Executive Director Jack Hoffbuhr discusses the fallout from Hurricane Katrina that hit the Gulf Coast of Louisiana and Mississippi in August of 2005. Specifically, he discusses putting a dollar value on the total cleanup and redevelopment cost, and additional Katrina costs that aren't even forseen yet and won't be felt for a number of years. The human factor (cost of lost homes, livelihoods, and scattered families), failures in the country's emergency response system, and the drain on government assistance compounded by the baby boomers beginning to collect their Social Security and Medicare benefits are all mentioned as factors that will demand greater attention than drinking water infrastructure needs. He states that the “value of water” message must be given more emphasis than ever to compete with these other issues.
The Piasa Creek Watershed Project: Cleaning up the muddy Mississippi
Authors: Lechevallier Mark W.
Published: February 2018

This article discusses a project to build a new water treatment plant in Alton, Illinois, when the old plant was completely submerged by the Great Flood of 1993. An environmental impact study showed that recycling the silt would not adversely affect the Mississippi River. Moreover, the 10‐year plan would reduce sediment erosion by 6,700 tons per year in the Piasa watershed, twice the discharge of the new treatment plant. The funds, managed by the not‐for‐profit Great Rivers Land Trust, would also protect up to 10,000 acres (4,047 ha) of land through acquisition, conservation easements, and wetlands restoration. The efforts would not only reduce soil erosion but would also improve water quality through pollution prevention and land conservation and help control storm water runoff through stream bank stabilization and fish and wildlife habitat restoration. The Great Rivers Land Trust also developed educational programs for school children and the community.
Rapidly Growing County Ensures Smooth Growth with a New SCADA System
Authors: Lesher Christine
Published: February 2018

This article discusses how installing a supervisory control and data acquisition system (SCADA) helped Brunswick County, North Carolina, deal with tremendous population growth, and to access and monitor the huge amounts of data collected each minute from the various sites throughout the country. Initially, a CitectSCADA system with 5,000 I/O points was installed. As the population grew, the system was upgraded to include 15,000 points. The system allows operators to check tank levels, pump station operations, and estimated time runs for the day, week, and month at any of the county's sites with a click of the mouse. All the operators' vehicles have laptops running the system to allow remote access to any site. Steps taken to protect the system from threats such as intruders or hurricanes are discussed along with allowances for future growth.
Comparison of Conventional and Biological Filter Performance for Cryptosporidium and microsphere removal
Authors: Amburgey James E. , Amirtharajah Appiah , York Marjorie T. , Brouckaert Barbara M. , Spivey Neal C. , Arrowood Michael J.
Published: February 2018

Previous studies involving filter runs seeded with oocysts have not shown significantly poorer removals during ripening. However, these studies typically did not seed oocysts throughout the preceding filter run, which is necessary for representative numbers of oocysts to be present in the backwash‐remnant water. In this study, four trials consisting of three to five consecutive filter runs were continuously seeded with oocysts and/or microsphere surrogates so that they would appear in the backwash‐remnant water of the successive run. Compared with concentrations in the postripening period, the concentrations of oocysts and microspheres found in the effluent under the influence of backwash‐remnant particles ranged from no higher to more than an order of magnitude higher, depending on filter type. Significant carryover of different‐colored microspheres was not observed in consecutive filter runs following the filter‐ripening period. During this study, conventional and biological filters showed similar average postripening oocyst and microsphere removals (roughly 1.7 and 2.1 log, respectively), but the biological filters exhibited significantly lower concentrations of oocysts and microspheres in the initial effluent samples containing backwash‐remnant particles left in the filter at the conclusion of the backwashing procedure.