bluuebunny/crossref_metadata_2025 huggingface dataset:
Three-dimensional simulation of flows in practical water-pump intakes
Authors: Li Songheng , Silva Jose Matos , Lai Yong , Weber Larry J. , Patel V. C.
Published: August 2018

The potential to use a three-dimensional (3D) computational fluid dynamics (CFD) model to produce the complexity of the flows in water-pump intakes and the prospects to use it as an effective assistant in the design or fixing of the related problems are reported. A scaled model of a real water-pump intake with flow conditions corresponding to the prototype was selected and studied. The Reynolds number of the model flow is 120 000, based on the diameter and bulk velocity in the pump column. The 3D CFD model solves the Reynolds averaged Navier–Stokes (RANS) equations with the k–ɛ turbulence model with wall function. A multi-block structured mesh was used. Numerical simulations are processed to reveal the important flow features in the entire flow field, compare the streamwise velocity distribution in the approaching channel, at and above the pump throat, as well as the swirl of flow at the pump throat. Numerical results provide insights into the complexity of flow around and inside the pump column under different incoming flows. This study makes significant strides from a simple intake to a real one and shows good prospects of further use of this 3D model to simulate flows in practical water-pump intakes.
Using a multi-objective genetic algorithm for SVM construction
Authors: Giustolisi Orazio
Published: August 2018

Support Vector Machines are kernel machines useful for classification and regression problems. In this paper, they are used for non-linear regression of environmental data. From a structural point of view, Support Vector Machines are particular Artificial Neural Networks and their training paradigm has some positive implications. In fact, the original training approach is useful to overcome the curse of dimensionality and too strict assumptions on statistics of the errors in data. Support Vector Machines and Radial Basis Function Regularised Networks are presented within a common structural framework for non-linear regression in order to emphasise the training strategy for support vector machines and to better explain the multi-objective approach in support vector machines' construction.

A support vector machine's performance depends on the kernel parameter, input selection and ε-tube optimal dimension. These will be used as decision variables for the evolutionary strategy based on a Genetic Algorithm, which exhibits the number of support vectors, for the capacity of machine, and the fitness to a validation subset, for the model accuracy in mapping the underlying physical phenomena, as objective functions. The strategy is tested on a case study dealing with groundwater modelling, based on time series (past measured rainfalls and levels) for level predictions at variable time horizons.
Groundwater pollution risk using a modified Latin hypercube sampling
Authors: Baalousha Husam
Published: August 2018

Characterisation of groundwater modelling involves significant uncertainty because of estimation errors of these models and other different sources of uncertainty. Deterministic models do not account for uncertainties in model parameters, and thus lead to doubtful output. The main alternatives for deterministic models are the probabilistic models and perturbation methods such as Monte Carlo Simulation (MCS). Unfortunately, these methods have many drawbacks when applied in risk analysis of groundwater pollution. In this paper, a modified Latin Hypercube Sampling method is presented and used for risk, uncertainty, and sensitivity analysis of groundwater pollution. The obtained results were compared with other sampling methods.

Results of the proposed method have shown that it can predict the groundwater contamination risk for all values of probability better than other methods, maintaining the accuracy of mean estimation. Sensitivity analysis results reveal that the contaminant concentration is more sensitive to longitudinal dispersivity than to velocity.
Evolutionary multi-objective optimization of the design and operation of water distribution network: total cost vs. reliability vs. water quality
Authors: Farmani Raziyeh , Walters Godfrey , Savic Dragan
Published: August 2018

An expanded rehabilitation of the hypothetical water distribution network of Anytown, USA is considered. As well as pipe rehabilitation decisions, tank sizing, tank siting and pump operation schedules are considered as design variables. Inclusion of pump operation schedules requires consideration of water system operation over the demand pattern period. Design of distribution storage facilities involves solving numerous issues and trade-offs such as locations, levels and volume. This paper investigates the application of multi-objective evolutionary algorithms in the identification of the pay-off characteristic between total cost, reliability and water quality of Anytown's water distribution system. A new approach is presented for formulation of the model. To provide flexibility, the network must be designed and operated under multiple loading conditions. The cost of the solution includes the capital costs of pipes and tanks as well as the present value of the energy consumed during a specified period. Optimization tends to reduce costs by reducing the diameter of, or completely eliminating, pipes, thus leaving the system with insufficient capacity to respond to pipe breaks or demands that exceed design values without violating required performance levels. Here a resilience index is considered as a second objective to increase the hydraulic reliability and the availability of water during pipe failures. Considering reliability as one of the objectives in the optimization process will decrease the level of vulnerability for the solutions and therefore will result in robust networks. However, oversized distribution mains and storage tanks will have adverse effects on water age with negative effects on water quality due to low flow velocity and little turnover, respectively. Therefore, another objective in the design and operation of distribution systems with storage facilities is the minimization of residence time, thus minimizing deterioration in water quality, which is directly associated with the age of water. Residence time must include not only the time in tanks but also the travel time before and after the water's entry into the storage facilities. The residence time of the water in the network is considered as a surrogate measure of water quality. Results are presented for the pay-off characteristics between total cost, reliability and water quality, for 24 h design and five loading conditions.
A symbolic data-driven technique based on evolutionary polynomial regression
Authors: Giustolisi Orazio , Savic Dragan A.
Published: August 2018

This paper describes a new hybrid regression method that combines the best features of conventional numerical regression techniques with the genetic programming symbolic regression technique. The key idea is to employ an evolutionary computing methodology to search for a model of the system/process being modelled and to employ parameter estimation to obtain constants using least squares. The new technique, termed Evolutionary Polynomial Regression (EPR) overcomes shortcomings in the GP process, such as computational performance; number of evolutionary parameters to tune and complexity of the symbolic models. Similarly, it alleviates issues arising from numerical regression, including difficulties in using physical insight and over-fitting problems. This paper demonstrates that EPR is good, both in interpolating data and in scientific knowledge discovery. As an illustration, EPR is used to identify polynomial formulæ with progressively increasing levels of noise, to interpolate the Colebrook-White formula for a pipe resistance coefficient and to discover a formula for a resistance coefficient from experimental data.
Information retrieval in hydrochemical data using the latent semantic indexing approach
Authors: Praus Petr , Praks Pavel
Published: August 2018

The latent semantic indexing (LSI) method was applied for the retrieval of similar samples (those samples with a similar composition) in a dataset of groundwater samples. The LSI procedure was based on two steps: (i) reduction of the data dimensionality by principal component analysis (PCA) and (ii) calculation of a similarity between selected samples (queries) and other samples. The similarity measures were expressed as the cosine similarity, the Euclidean and Manhattan distances. Five queries were chosen so as to represent different sampling localities.

The original data space of 14 variables measured in 95 samples of groundwater was reduced to the three-dimensional space of the three largest principal components which explained nearly 80% of the total variance. The five most proximity samples to each query were evaluated.

The LSI outputs were compared with the retrievals in the orthogonal system of all variables transformed by PCA and in the system of standardized original variables. Most of these retrievals did not agree with the LSI ones, most likely because both systems contained the interfering data noise which was not preliminary removed by the dimensionality reduction. Therefore the LSI approach based on the noise filtration was considered to be a promising strategy for information retrieval in real hydrochemical data.
Stochastic multiobjective reservoir operation under imprecise objectives: multicriteria decision-making approach
Authors: Akbari M. , Afshar A. , Mousavi S. Jamshid
Published: August 2018

Multiobjective reservoir operations are generally complex, as they are often associated with a large quantity of uncertain factors in combination with noncommensurable objectives. In this study, fuzzy-state stochastic dynamic programming (FSDP) and multicriteria decision-making (MCDM) are integrated to derive operating rules for a single multiobjective reservoir operation problem. The model addresses uncertainties due to randomness in inflows and imprecision in variables' discretization and objectives. The FSDP model takes into account uncertainties due to the random nature of inflows and imprecision due to variable discretization. Imprecise and noncommensurable objectives are quantified by a set of subjective criteria, the aggregation of which is performed through an MCDM model, by which possible decisions at every stage of the FSDP model are evaluated and compared. The proposed approach is then employed in deriving operating rules for the Karoon 1 reservoir in south-west Iran and the rules are tested and evaluated through simulation. Results show the model's capability in handling different kinds of uncertainties involved in real reservoir operation problems.
Watershed issues associated with Clostridium botulinum: A literature review
Authors: Long Sharon C. , Tauscher Tiffany
Published: August 2018

Botulism the disease, the related organism (Clostridium botulinum) and toxin have gained renewed attention in these times of heightened homeland security and bioterrorism preparedness. Since C. botulinum is ubiquitous in nature, botulism outbreaks resulting from environmental exposure can be of concern to watershed managers and drinking water utilities. This paper reviews aspects of naturally occurring C. botulinum in light of concerns for source water watersheds. Information regarding sources and occurrence of botulism, C. botulinum and botulism toxins are discussed. Ecology and physiology of environmental C. botulinum and cycles of disease are reviewed. Finally, the effectiveness of water treatment and disinfection measures is discussed.
Identification by microarray of a common pattern of gene expression in intact intestine and cultured intestinal cells exposed to virulent Aeromonas hydrophila isolates
Authors: Hayes Samuel L. , Lye Bethany R. , Lye Dennis J. , Rodgers Mark R. , Stelma Gerard , Malard Joel M. , Vandewalle Alain , Vesper Stephen J.
Published: August 2018

The genus Aeromonas comprises known virulent and avirulent isolates and has been implicated in waterborne disease. A common infection model of human gastroenteritis associated with A. hydrophila uses neonatal mice. The goal of this research was to evaluate whether a murine small intestinal cell line could provide comparable results to the gene expression changes in the neonatal mouse model. Changes in mRNA expression in host cell cultures and intestinal tissues were measured after exposure to virulent Aeromonas hydrophila strains. A. hydrophila caused the up-regulation of more than 200 genes in neonates and over 50 genes in cell culture. Twenty-six genes were found to be in common between the two models, of which the majority are associated with the innate immune response.
Water systems and urban sanitation: A historical comparison of Tokyo and Singapore
Authors: Otaki Yurina , Otaki Masahiro , Sakura Osamu
Published: August 2018

The importance of a water supply and sewage treatment for urban sanitation is recognized in the modern world. Their contributions to public health have not, however, been well demonstrated by historical data, especially in Asian cities. In this research, we focused on the Asian cities of Tokyo and Singapore, which both developed significantly in the 20th century. We analysed their development processes statistically to determine what the key elements for the protection of urban sanitation have been. Although both cities constructed modern water supply systems at almost same time (Tokyo in 1898 and Singapore in 1878), and similarly modern wastewater treatment systems (Tokyo in 1922 and Singapore in 1913), the prevalence of water-borne diseases in Tokyo was more serious than it was in Singapore, in spite of Singapore's high infant mortality rate. The main reason for this was the differences in the systems of night-soil transport. We found that the water supply system in itself was not enough to resolve all urban sanitation problems, and appropriate night-soil removal was also crucial. In addition, historical trends and water consumption vary by city, so the appropriate technology and system are also different according to the unique characteristics and needs of each.
Hepatitis A virus in surface water in South Africa: what are the risks?
Authors: Venter J. M. E. , van Heerden J. , Vivier J. C. , Grabow W. O. K. , Taylor M. B.
Published: August 2018

The aim of this study was to assess the potential risk of infection constituted by HAV to persons using surface dam and river water for domestic and recreational purposes. It estimates the potential risk using a deterministic exponential risk assessment model with mean values and conservative assumptions. Hepatitis A virus was detected in 17.5% of river and 14.9% of dam water samples tested. The number of indicator organisms in these sources exceeded drinking and recreational water quality guidelines set by the United States Environmental Protection Agency (US EPA), indicating possible health risks to recreational water users. Based on the available data and taking all the assumptions into consideration, the probability of infection (Pinf) to the higher socio-economic population using the river water for recreational purposes was 1.1 × 10−3 per day and 3.3 × 10−1 per annum if 100 ml was ingested per day. For recreation in the dam water the Pinf value was 1.2 × 10−4 per day and 4.2 × 10−2 per annum. For the lower socio-economic population, risk values for drinking purposes (2 L day−1) were ten-fold greater. These surface waters therefore did not conform to the US EPA guidelines of 1 infection per 10,000 consumers per year for drinking water or eight gastrointestinal illnesses per 1,000 bathers per day in environmental waters used for recreational purposes. This is the first risk assessment study addressing the risk of infection by HAV in surface water to different socio-economic populations in South Africa.
Effect of specialized bathing systems on resident cleanliness and water quality in nursing homes: a randomized controlled trial
Authors: Sloane Philip D. , Cohen Lauren W. , Williams Christianna S. , Munn Jean , Preisser John S. , Sobsey Mark D. , Wait Douglas A. , Zimmerman Sheryl
Published: August 2018

A randomized controlled trial evaluated the impact of different methods of water agitation on clinical and microbiological outcomes in 31 nursing home residents. Four conditions were tested: a) whirlpool tub, jets on, using standard soap products; b) ultrasound tub, ultrasound on, using the standard soap products; c) ultrasound tub, ultrasound on, using specialized soap and skin conditioner; and d) either tub (randomized), water circulation off, using standard soap products (the control condition). Outcomes of interest included skin microbial flora, water microbial flora, skin condition, time spent bathing, and staff satisfaction.

Resident skin condition and skin microbial flora did not differ between the four treatments. The tubs also did not differ in terms of bacterial colonization; however, there was a non-statistically significant trend for the highest counts to occur in whirlpool tubs after being idle overnight. The ultrasound and whirlpool tubs were preferred by staff over the control treatment (still water) in terms of sound and overall suitability. In addition, staff reported that the ultrasound tub using enhanced skin cleansers made bathing residents easier and faster than the same tub using standard cleansers.
A comparison of ten USEPA approved total coliform/E. coli tests
Authors: Olstadt Jeremy , Schauer James Jay , Standridge Jon , Kluender Sharon
Published: August 2018

Since 2002, the United States Environmental Protection Agency (USEPA) has approved ten enzyme-based total coliform and E. coli detection tests for examination of drinking water. These tests include: Colilert®, Colilert-18®, Colisure®, m-Coli Blue 24®, Readycult® Coliforms 100, Chromocult®, Coliscan®, E*Colite®, Colitag™ and MI Agar. The utility of the enzyme based test systems is based on both the ability of the test to detect the target organisms at low levels and the ability of the test system to suppress the growth of non-target organisms that might result in false positive results. Differences in the ability of some of these methods to detect total coliform and E. coli, as well as suppress Aeromonas spp., a common cause of “false positive” results, have been observed. As a result, this study was undertaken to elucidate the strengths and weaknesses of each method. Water samples were collected from three geographically and chemically diverse groundwaters in Wisconsin. One-hundred milliliter aliquots were individually spiked with both low concentrations (one to ten organisms) and high concentrations (fifty to one-hundred) of each of five different total coliform organisms (Serratia, Citrobacter, Enterobacter, E. coli, & Klebsiella). These spiked samples were used to test the capability of ten enzyme-based test systems to both detect and enumerate the spiked organisms. In addition, 100 ml samples were independently spiked with two different strains of Aeromonas spp. at six different levels, to assess the ability of each enzyme-based test to suppress Aeromonas spp. Analysis of the data indicated that wide variability exists among USEPA approved tests to detect and quantify total coliforms, as well as suppress Aeromonas spp.
The effectiveness of large household water storage tanks for protecting the quality of drinking water
Authors: Graham Jay P. , VanDerslice James
Published: August 2018

Many communities along the US-México border remain without infrastructure for water and sewage. Residents in these communities often collect and store their water in open 55-gallon drums. This study evaluated changes in drinking water quality resulting from an intervention that provided large closed water storage tanks (2,500-gallons) to individual homes lacking a piped water supply. After the intervention, many of the households did not change the source of their drinking water to the large storage tanks. Therefore, water quality results were first compared based on the source of the household's drinking water: store or vending machine, large tank, or collected from a public supply and transported by the household. Of the households that used the large storage tank as their drinking water supply, drinking water quality was generally of poorer quality. Fifty-four percent of samples collected prior to intervention had detectable levels of total coliforms, while 82% of samples were positive nine months after the intervention (p < 0.05). Exploratory analyses were also carried out to measure water quality at different points between collection by water delivery trucks and delivery to the household's large storage tank. Thirty percent of the samples taken immediately after water was delivered to the home had high total coliforms (>10 CFU/100 ml). Mean free chlorine levels dropped from 0.43 mg/l, where the trucks filled their tanks, to 0.20 mg/l inside the household's tank immediately after delivery. Results of this study have implications for interventions that focus on safe water treatment and storage in the home, and for guidelines regarding the level of free chlorine required in water delivered by water delivery trucks.
A critical evaluation of a flow cytometer used for detecting enterococci in recreational waters
Authors: King Dawn N. , Brenner Kristen P. , Rodgers Mark R.
Published: August 2018

The current U. S. Environmental Protection Agency-approved method for enterococci (Method 1600) in recreational water is a membrane filter (MF) method that takes 24 hours to obtain results. If the recreational water is not in compliance with the standard, the risk of exposure to enteric pathogens may occur before the water is identified as hazardous. Because flow cytometry combined with specific fluorescent antibodies has the potential to be used as a rapid detection method for microorganisms, this technology was evaluated as a rapid, same-day method to detect enterococci in bathing beach waters. The flow cytometer chosen for this study was a laser microbial detection system designed to detect labeled antibodies. A comparison of MF counts with flow cytometry counts of enterococci in phosphate buffer and sterile-filtered recreational water showed good agreement between the two methods. However, when flow cytometry was used, the counts were several orders of magnitude higher than the MF counts with no correlation to Enterococcus spike concentrations. The unspiked sample controls frequently had higher counts than the samples spiked with enterococci. Particles within the spiked water samples were probably counted as target cells by the flow cytometer because of autofluorescence or non-specific adsorption of antibody and carryover to subsequent samples. For these reasons, this technology may not be suitable for enterococci detection in recreational waters. Improvements in research and instrument design that will eliminate high background and carryover may make this a viable technology in the future.
Development of a process-based model to predict pathogen budgets for the Sydney drinking water catchment
Authors: Ferguson Christobel M. , Croke Barry F. W. , Beatson Peter J. , Ashbolt Nicholas J. , Deere Daniel A.
Published: August 2018

In drinking water catchments, reduction of pathogen loads delivered to reservoirs is an important priority for the management of raw source water quality. To assist with the evaluation of management options, a process-based mathematical model (pathogen catchment budgets - PCB) is developed to predict Cryptosporidium, Giardia and E. coli loads generated within and exported from drinking water catchments. The model quantifies the key processes affecting the generation and transport of microorganisms from humans and animals using land use and flow data, and catchment specific information including point sources such as sewage treatment plants and on-site systems. The resultant pathogen catchment budgets (PCB) can be used to prioritize the implementation of control measures for the reduction of pathogen risks to drinking water. The model is applied in the Wingecarribee catchment and used to rank those sub-catchments that would contribute the highest pathogen loads in dry weather, and in intermediate and large wet weather events. A sensitivity analysis of the model identifies that pathogen excretion rates from animals and humans, and manure mobilization rates are significant factors determining the output of the model and thus warrant further investigation.
Microbiological quality of fish grown in wastewater-fed and non-wastewater-fed fishponds in Hanoi, Vietnam: influence of hygiene practices in local retail markets
Authors: Thi Phong Lan Nguyen , Dalsgaard Anders , Cam Phung Dac , Mara Duncan
Published: August 2018

Mean water quality in two wastewater-fed ponds and one non-wastewater-fed pond in Hanoi, Vietnam was ∼106 and ∼104 presumptive thermotolerant coliforms (pThC) per 100 ml, respectively. Fish (common carp, silver carp and Nile tilapia) grown in these ponds were sampled at harvest and in local retail markets. Bacteriological examination of the fish sampled at harvest from both types of pond showed that they were of very good quality (2−3 pThC g−1 fresh muscle weight), despite the skin and gut contents being very contaminated (102−103 pThC g−1 fresh weight and 104−106 pThC g−1 fresh weight, respectively). These results indicate that the WHO guideline quality of ≤1000 faecal coliforms per 100 ml of pond water in wastewater-fed aquaculture is quite restrictive and represents a safety factor of ∼3 orders of magnitude. However, when the fish from both types of pond were sampled at the point of retail sale, quality deteriorated to 102−105 pThC g−1 of chopped fresh fish (mainly flesh and skin contaminated with gut contents); this was due to the practice of the local fishmongers in descaling and chopping up the fish from both types of pond with the same knife and on the same chopping block. Fishmonger education is required to improve their hygienic practices; this should be followed by regular hygiene inspections.
Reduction of trihalomethane formation and detoxification of microcystins in tap water by ozonation
Authors: Thapsingkaew Orapin , Kijjanapanich Vilailuck , Ruangyuttikarn Werawan
Published: August 2018

The efficiency of ozonation in comparison to chlorination for removal of microcystins and production of trihalomethanes (THMs) in water was investigated. One hundred and ninety water samples of ozone and chlorine treated water were collected at a water treatment plant between August 2004 and March 2005. The level of THMs, total organic carbon and residual chlorine were determined. Protein phosphatase 2A inhibition assay was used to detect microcystins and the presence of microcystins was confirmed by HPLC. The results show that 91.5% of the THM species in treated water was chloroform and 8.5% was bromodichloromethane. The mean THM level± standard error of mean in chlorinated water (CW) (45.1±3.0 μg/L) was higher than the mean of THM level in ozonated water (OW) (18.6±2.2 μg/L). In addition, no OW sample exceeded the first stage U.S. EPA maximum THM contaminant level for drinking water (80 μg/L) and only 8% of these samples exceeded the second stage level (40 μg/L). On the other hand, 3% of CW samples exceeded 80 μg/L and 68% exceeded the 40 μg/L level. The microcystin level in all water samples was below the WHO guideline value (1 μg/L) for drinking water.
Mycobacterium avium in a shower linked to pulmonary disease
Authors: Falkinham Joseph O. , Iseman Michael D. , de Haas Petra , van Soolingen Dick
Published: August 2018

Mycobacterium avium was isolated from hot and cold water samples and from sediment (biofilm) collected from the showerhead in the home of a woman with M. avium pulmonary disease lacking known M. avium risk factors. IS1245/IS1311 DNA fingerprinting demonstrated that M. avium isolates from the hot and cold water and showerhead sediment demonstrated a clonal relationship with the patient's M. avium isolate. The data provide evidence that showers may serve as sources of infection by waterborne M. avium.
Detection and molecular characterization of swine hepatitis E virus in North Carolina swine herds and their faecal wastes
Authors: Kase Julie A. , Correa Maria T. , Sobsey Mark D.
Published: August 2018

Recent findings of almost genetically indistinguishable swine and human strains, have suggested swine play a role in the transmission of hepatitis E virus (HEV). The extent to which HEV may be present and persist in the faecal waste generated from intensive swine operations is largely unknown. The fate of swine waste liquid is often land application, possibly resulting in unintentional seepage into groundwater or run-off into surface waters, hence validating concerns of human exposure risks. Freshly passed swine faeces, barn flush liquid waste, and lagoon liquid from production sites in North Carolina were surveyed periodically for HEV using RT-PCR primers located in ORF2. On three farms where HEV RNA was detected in swine faeces, it was also found in stored liquid waste on several occasions. HEV presence was related to swine age but not to animal management and waste management procedures, which varied amongst the farms. Seasonal patterns of HEV prevalence could not be established as viral RNA was isolated at all time points from two farms. Phylogenetic analysis of 212 bases of the genomic RNA indicated that isolates resembled the known US swine and human strains (percentage nucleic acid homology 91 to 94%), with one amino acid substitution.
Drinking water incidents due to chemical contamination in England and Wales, 2006–2008
Authors: Paranthaman Karthikeyan , Harrison Henrietta
Published: August 2018

Contamination of drinking water by microbiological and chemical agents can lead to adverse health effects. In England and Wales, the Chemicals Hazards and Poisons Division (CHaPD) of the Health Protection Agency provides expert advice on the consequences to public health of chemical contamination incidents affecting drinking water. In this study, we extracted data from the National Database on the type and nature of drinking water contamination events reported to the CHaPD between 2006 and 2008. Eighty-two incidents with confirmed chemical contamination were identified. Among the 70 incidents where data was available, 40% (28/70) of incidents related to contamination of drinking water provided by private suppliers, 31% (22/70) were due to contamination occurring close to the point of consumption (i.e. near consumer) and 29% (20/70) related to incidents where public water supplies were identified as the contaminated source. For the majority of incidents, little or no information was available on the critical exposure variables such as duration of contamination and actual or estimates of the population affected. Reassuringly, the levels of exposure in most incidents were considered unlikely to cause serious immediate or long term ill health effects. Recording of exposure data for reported contamination incidents needs to be improved.
Retronasal perception and flavour thresholds of iron and copper in drinking water
Authors: Omur-Ozbek Pinar , Dietrich Andrea M.
Published: August 2018

Drinking water flavour has a strong role in water quality perception, service satisfaction, willingness to pay and selection of water sources. Metallic flavours are often caused by the dissolved iron and copper, commonly found in groundwater or introduced to tap water by corroding infrastructure. Taste thresholds of iron and copper have been investigated by several studies; however, reported results and test methods vary considerably. This study determined the taste thresholds of ferrous and cuprous ions in room temperature reagent water by using the one-of-five test with multi-nation panellists in the United States. For ferrous and cuprous ions, individual thresholds ranged from 0.003 to >5 mg l−1 and 0.035 to >5 mg l−1, respectively. Population thresholds were determined by logistic regression and geometric mean methods as 0.031 and 0.05 mg l−1 for ferrous ion, and 0.61 mg l−1 for cuprous ion by both methods. The components of metallic sensation were investigated by use of nose-clips while panellists ingested iron and copper solutions. Results showed that metallic sensation has a significant odour component and should be treated as a flavour instead of a taste. Ferrous, cuprous and cupric ions also produced weak bitter and salty tastes as well as astringent mouthfeel. In comparison, ferric ion produced no sensation.
PILOT PROJECTS IN BATHROOMS: A NEW CHALLENGE FOR WASTEWATER PROFESSIONALS
Authors: Lienert J. , Larsen T. A.
Published: August 2018

Household-centered technologies such as urine source separation (NoMix technology) could induce a paradigm change in urban wastewater management, hereby improving water pollution control and resource management. Technological innovations need real-world application for further development. The Swiss research project Novaquatis accompanied five pilot projects from 1997 on. We give a systematic overview of our experience, summarizing various important aspects, a fundamental one being a clearly defined goal. Early stakeholder involvement is crucial, because the still imperfect NoMix technology depends on people's goodwill. We reference data sheets, legal documents, etc. and make suggestions for installation, maintenance, and technology improvement. We identify areas for future research necessitating pilot projects and discuss their requirements to optimize the cost-benefit factor. This paper is intended as support to wastewater professionals to avoid the most serious pitfalls when conducting NoMix pilot projects. It contributes to increased interaction between research and real-world application of urban European household innovations.
GTZ Supported Ecosan Projects in India
Authors: Werner C. , Wafler M. , Heeb J. , Bartels H. , Panse D.
Published: August 2018

To promote the ecological sanitation approach in India, the Indian Innovative Ecological Sanitation Network (IIESN) was established through a joint effort supported by the GTZ, local partners in India and other international partners. IIESN is expected to develop innovative and socially accepted ecological sanitation systems for India and explore operational, institutional and economical models for the implementation of those ecological sanitation systems. Current activities include the implementation of several demonstration projects in different areas of India. The projects comprise e.g. eco-friendly public toilets, school and individual toilets. The flexibility of the ecosan approach allows its incorporation in various local situations and adapted to the local reuse opportunities. Technologies of the demonstration projects comprise urine separating dehydration toilets, waterless urinals, urine storage, greywater treatment and black- or brownwater treatment with anaerobic digestion and constructed wetlands. Reuse options are the use of urine, dried faeces and sludge for fertilisation, use of treated water (greywater, kitchen wastewater, anal cleansing water, black- or brownwater) for irrigation and beautification and use of biogas for cooking,
Agriculture and Groundwater Protection - a Common Effort to Tackle the Nitrate Problem in Northern Bavaria, Germany
Authors: Haas Bettina , Lukas Heiko , Bauer Axel
Published: August 2018

Due to low groundwater recharge rates and intensive agricultural land use, elevated nitrate concentrations in groundwater are measured in Lower Franconia, Bavaria (Germany). Analysis of cultivation practice in this region showed that crops with high nitrogen-surplus were cultivated to a significant extent. By the example of a catchment area where drinking water is extracted, an approach for a change in agricultural land use was tested. Fields were classified according to soil quality and the type of sub-soil. Measures like conversion of arable land into grassland or changes in type of crop that is grown, were adjusted to the local (field) conditions. Thus nitrogen surplus could be reduced to half by the extensification of one third of the agricultural land. Due to the classification system, the measures are realised in the most cost-effective way as well.
Groundwater management in Vojvodina
Authors: Djuric D. , Josipovic J. , Jevtic G. , Slimak T. , Pusic M.
Published: August 2018

Past utilization of groundwater resources in Vojvodina (the Serbian part of the Pannonian Basin) has resulted in a number of water supply problems, particularly insufficient water quantities and the deterioration of water quality. Increasing pressure on groundwater resources has resulted in over-abstraction (aquifer “mining”), with current abstraction rates exceeding sustainable yield. Water supply in Vojvodina is generally based on a groundwater aquifer (generally referred to as “the main” aquifer) which is shared with Hungary, Romania and Croatia. In order to achieve a better balance in groundwater utilization between the environment and water users (i.e. to establish a sound basis for sustainable utilization, management and protection of the transboundary aquifer), the development of new, renewable groundwater sources in the Danube and Sava alluvions has been proposed.
Selected groundwater studies of EU project AquaTerra leading to large-scale basin considerations
Authors: Barth J.A.C. , Kalbus E. , Schmidt C. , Bayer-Raich M. , Reinstorf F. , Schirmer M. , Thiéry D. , Dubus I.G. , Gutierrez A. , Baran N. , Mouvet C. , Petelet-Giraud E. , Négrel Ph. , Banton O. , Batlle Aguilar J. , Brouyère S. , Goderniaux P. , Orban Ph. , Rozemeijer J.C. , Visser A. , Bierkens M.F.P. , Van der Grift B. , Broers H.P. , Marsman A. , Klaver G. , Slobodnik J. , Grathwohl P.
Published: August 2018

Several local groundwater studies within the EU project AquaTerra in the Basins of the Meuse, Elbe point at significant influences of groundwater on surface water, while the Brévilles Catchment shows a distinct problematic of pesticide loading to groundwater. Further modeling studies are currently being developed. In the Danube Basin no specific groundwater studies were carried out in the framework of AquaTerra. However on larger scales geochemical proxies such as strontium isotope ratios can give an insight into groundwater contributions to the river that reflects an integral signal of the environmental status of the Basin. Future local groundwater studies should be further correlated to the environmental status of rivers nearby.
Artificial recharge of groundwater in The Netherlands
Authors: Tielemans M.W.M.
Published: August 2018

After a short general overview of the Dutch drinking water industry, the artificial recharge projects run by three drinking water companies situated in the West of The Netherlands are described in some detail. Because all the other groundwater in this part of the country is brackish, fresh groundwater from the sandy dunes along the coast has been employed as a source for drinking water from 1854. Since over 50 years, the fresh water reserves in the dunes are recharged with pretreated water from the rivers Meuse and Rhine and from the lake IJsselmeer. The various pretreatment steps, infiltration and abstraction practices and the final treatment steps employed are described, and related water quality issues are discussed. The drinking water produced is of high quality, is biologically stable and is distributed without additional disinfection. The drinking water companies put considerable effort in the protection of their water sources through (international) lobby organizations such as RIWA and IAWR, by cooperating with the water authorities and by carrying out specific projects aimed at reduction of emissions to the surface water. The presence of the drinking water companies has prevented residential development in the dunes, thus preserving unique nature in the most densely populated area in the country. Nature conservation and recreational aspect of the artificial recharge projects are described briefly.
Securing groundwater use and reestablishing the water balance by artificial recharge of groundwater in the region of Marchfeld, Austria
Authors: Neudorfer W. , Weyermayer H.
Published: August 2018

In the Marchfeld - a region of about 1000 km2 in eastern Austria - groundwater is used intensively for irrigation as well as for industrial and potable purposes which has led to a considerable decline of the groundwater table. As a countermeasure the Marchfeldkanal Project was started in 1984 in order to secure the important groundwater reservoir in this dry area. The Marchfeldkanal system was designed as a multi-purpose project, with the aim of providing external water to the region. Beside replenishing the groundwater by artificial recharge now surface water is available for irrigation. Further effects are the improvement of surface water quality and a new protection against floods. It was set store to a very natural design of all parts of the system, in particular of the watercourses. So the Marchfeldkanal System has become an appreciated recreation area. Presently, the system has been completed and three groundwater recharge facilities are operational after periods of testing operation. The next step will be the selective infiltration of surface water, which is withdrawn again by a drinking water abstraction of a local town.
The Italian way to prevent groundwater contamination risk
Authors: Civita M. V. , De Maio M. , Fiorucci A.
Published: August 2018

In the early 1980's the Italian scientific community, together with a number of institutional decision-makers, realized how urgent it was to protect natural and environmental resources. They agreed that an adequate level of scientifically organized knowledge allows the accurate planning and development of environmental systems through management and direction of the actual development process, without hindering it. Since the special project was first set up in 1984, as part of the GNDCI-CNR (National Group for the Defence against Hydrogeologic Disasters, of the Italian National Council of Research) scientific context, it has been the cardinal point of Research Line 4 “Assessment of Aquifer Vulnerability”. The problem of groundwater contamination was examined in this project for the very first time in Italy in an organic and extensive manner as a key for forecasting and prevention purposes. The Italian approaches to assessing and mapping groundwater vulnerability to contamination are essentially based on two main methodologies:- The GNDCI Basic Method a HCS (Hazard Contamination Source) type approach that can be used for any type of Italian hydrogeologic situation, even where there is a limited amount of data. A unified legend and symbols are also defined for each hydrogeologic level.- The SINTACS [Soggiacenza (depth to groundwater); Infiltrazione (effective infiltration); Non saturo (unsaturated zone attenuation capacity); Tipologia della copertura (soil/overburden attenuation capacity); Acquifero (saturated zone characteristics); Conducibilità (hydraulic conductivity); Superficie topografica (Slope)] method, a PCSM (Point Count System Model) developed for use prevalently in areas with good data base coverage.

The methodological approaches described in this paper now make up the Italian standard which has been set in the recent very important Italian Law (152/99) and which has now been ratified in the national guidelines produced by ANPA, the Italian National Agency for Environment Protection. In this paper the structure of the Research Line, the progress obtained by the 21 Research units (over 100 researchers) in 20 years of activity, the results gained etc. are briefly highlighted.
Effects of urgent measures implemented to protect the Kljuc groundwater source
Authors: Radenkovic Z. , Boreli-Zdravkovic Dj. , Zuber-Radenkovic V.
Published: August 2018

The “Kljuc” groundwater source in the alluvion of the Velika Morava River provides water supply for the City of Pozarevac at a rate of roughly 220 l/s. Groundwater is abstracted by means of tube wells which are up to 20 m deep. Since 2000, nitrate concentrations in water at this source had a continuous upward trend. Constant intrusion of groundwater with nitrate concentrations higher than 100 mg/l, mainly from suburbs which have no access to utility services, led to a temporary shutdown of the source in 2006. However, following the construction and commissioning of an infiltration-based protection system, a hydraulic barrier was created which allowed the water source to continue to service the public water supply system. This paper presents the performance of this system during the period from September 2006 to March 2007.
RECYCLED WATER RISK PERCEPTION - A COMPARISON OF TWO CASE STUDIES
Authors: Hurlimann A.
Published: August 2018

This paper reports results from a study comparing perceived risk associated with various recycled water uses in two Australian locations, both in the state of Victoria: the capital city Melbourne, and Bendigo a regional urban centre. Both locations are experiencing ‘drought’, but Bendigo is experiencing this in a more acute manner. A case study is used in each location. Both case studies involve future use of recycled water in new commercial buildings. An on-line survey was used to measure attitudes to recycled water of the future occupants of both buildings. The study found perceived risk associated with 11 uses of recycled water increased as the use became increasingly personal. Interestingly, no difference in perceived risk associated with 11 uses of recycled water was found between locations. Prior experience (use) of recycled water was found to be a significant and positive factor in reducing risk perception. Various attitudinal variables were found to be significant influences on perceived risk. Results indicate that reducing perceived risk of recycled water use may increase satisfaction with its use.
WATER CONSERVATION PLANNING IN AUSTIN, TEXAS
Authors: Gregg Tony , Gross Drema
Published: August 2018

Despite a long-standing, aggressive water conservation program, the City of Austin needed to develop additional conservation strategies to meet a City Council goal of reducing water use by 1 percent a year for ten years. This paper details the strategies discussed and ultimately recommended by staff and a Council-formed Water Conservation Task Force over a hectic 120-day period.
PRACTICAL EXPERIENCES IN APPLYING ADVANCED SOLUTIONS FOR CALCULATION OF FREQUENCY OF INTERVENTION WITH ACTIVE LEAKAGE CONTROL: RESULTS OBTAINED
Authors: Benvenuti Diego , Fantozzi Marco
Published: August 2018

Due to the activities of the Water Loss Task Force, Utilities are becoming increasingly encouraged to measure inflows to small distribution systems. However, in the experience of the Authors, there are two common problems. Firstly, new potential users are often discouraged by the high initial cost of permanent metering and data transmission. Secondly, they are unaware that pressure measurements, together with the flow data, often allows rapid quantification of water loss management opportunities without the need for setting up detailed network analysis models.

The paper will explain the type of broad conclusions that can be obtained from occasional reliable measurements of Zone inflows with portable equipment and the additional conclusions and predictions that can be obtained from pressure measurements at a few selected locations.

The paper will also describe a low cost data transfer by e-mail and a software that will allow users to quickly identify an economic frequency of intervention for an active leakage control.