bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computer-aided rehabilitation of water networks (CARE-W)
Authors: Sægrov S. , Schilling W. , Røstum J. , Tuhovcak L. , Eisenbeis P. , Herz R. , LeGauffre P. , Melo Baptista J. , Conroy P. , deFederico V. , Mazzacane S. , Schiatti M. 
Published: May 2018

The project CARE-W presented in this paper deals with the public water supply networks and their problems of ageing such as structural failures, hydraulic insufficiencies, leakage, deteriorating water quality and increasing maintenance cost that impact on an urban environment. The ultimate goal of the project is to develop a suite of tools, which provide the most cost-efficient system of maintenance and repair of water distribution networks, with the aim to guarantee a security of water supply that meets social, health, economic and environmental requirements. The paper comprises a description of the project work-packages, which include: a control panel of Performance Indicators (PIs) for rehabilitation;a description of technical and statistical tools assessing and forecasting some of the PI;a procedure to define the best choice for annual rehabilitation programming;a procedure to define the best strategy of planning rehabilitation investments (at long term, 10 to 20 years);a software, combining the above products with a common database, tested and evaluated by several test cities.
CARE-W is aimed at utilities for water supply systems, operating companies, local authorities, financial institutions and national regulators. It is supported by the European Commission under the fifth framework programme.
Whole life costing: application to water distribution network
Authors: Engelhardt M. , Savic D. , Skipworth P. , Cashman A. , Saul A. , Walters G. 
Published: May 2018

There is an increasing pressure from the economic regulator in England and Wales for water companies to ensure that their capital maintenance decisions reflect an understanding of the long-term impact on their operational costs and risks. This implies that decisions must not only reflect the costs borne now but the likely costs in the future, and how these might be optimised. It is noteworthy that within the construction and transport industries, asset management decisions which have been driven in this direction utilise a whole life costing (WLC) methodology. This paper addresses the implications of transferring the concept of WLC to service-based assets such as water systems.
A WLC approach to distribution network management aims to achieve the lowest network provision and operating cost when all costs are considered to achieve standards enforced by regulation. Cognisance is to be taken of all relevant costs - direct and indirect, private and societal - in order to balance the needs of the service supplier, the customer, society and the environment in a sustainable manner. A WLC analysis thus attempts to develop a cost profile over the life of the asset. Accounting for the costs over this period is achieved through a combination of activity based costing (ABC) and a life cycle assessment (LCA) used to identify potential social and environmental costs. This process means that each of these identified costs must be linked to some physical parameter that itself varies over time due to changing demands on the system, the different operational strategies available to the operator and natural deterioration of the fabric of the system. The links established between the cost and activities of the operator provide the basis for the development of a WLC decision tool (WiLCO) for application to water distribution network management.
Pressure management in Waitakere City, New Zealand - a case study
Authors: Pilipovic Z. , Taylor R. 
Published: May 2018

In 1996, as part of Waitakere Council’s Water Cycle Strategy, a pressure standardisation programme to permanently lower the average supply pressure citywide was implemented with the aim of reducing water loss and water use. The experience gained during the 1994/95 Auckland water shortage had confirmed that there was considerable scope to reduce pressures in many areas.
Since 1996 water pressures have been reduced in over 60% of the reticulated area of the city, with the average pressure reduced from 710 kPa to 540 kPa. As a result of this programme water loss from the network has been reduced, there has been a reduction in the frequency of mains breaks and it is likely that the life of water pipeline assets has been extended. Furthermore both pressure and demand management initiatives have reduced per capita water use in the city by more than 10%.
A network computer model was used as a design tool to check the network under various pressure regimes and cost benefit analyses were carried out for various design scenarios. Fire sprinkler systems were checked as part of the design process. Minimum service standards were not reduced and in some cases pressures were actually increased. This paper covers the various aspects of the design, the implementation and the results of the pressure standardisation programme.
An integrated approach to water distribution network monitoring and performance prediction using geographical information systems
Authors: Poulton M. 
Published: May 2018

The deterioration of water distribution systems and the subsequent need for major rehabilitation has provided researchers with a challenge: to seek new techniques to facilitate decision-making and assist network planners. Consequently, a range of methods have been developed, concerning several key performance indicators. Those with the greatest potential tend to promote a pro-active approach to pipeline rehabilitation, by predicting future performance of individual or groups of pipes. Such an approach is essential if cost-effective solutions are to be found.
Prediction models are based on indicators that are perceived to be the most appropriate for measuring and comparing an aspect of performance. The level of “appropriateness” is influenced not only by the availability of data and the ease at which it can be recorded, but also its accuracy and unambiguity. Consequently, indicators such as burst rates are widely used to assess structural performance. Ideally though, a more direct measure of the condition of a pipe could be used, such as its remaining wall thickness. This has previously been largely disregarded, due to the lack of appropriate (non-destructive) measurement technology. However, technological advances are being made to enable the inline monitoring of pipes and determination of deficiencies (particularly corrosion pits in cast iron pipes).
This paper illustrates how online condition monitoring of distribution pipelines can be combined with existing prediction models, to facilitate the decision-making process. Integration is achieved through the use of a Geographical Information System (GIS), which greatly enhances representation of spatial and temporal information.
Profit and principles: finding a balance with the triple bottom line
Authors: Adam C. 
Published: May 2018

Many Water Authorities throughout Australia have been through or are in the process of reforming their operations. For many, this means operating on a more commercial basis, with a progressively greater emphasis on the financial performance of their services. In many cases, these changes have led to a significant increase in the commercial performance of these businesses to the benefit of both the Water Authority and the broader community.
While recognizing commercial viability as a fundamental prerequisite for sustainable development, given the nature of the urban water industry and its central importance in maintaining living standards and addressing environmental issues, progressive managers are beginning to ask the question: “Is our commercial performance the single or even best measure of “success” in the management of our water services?”
Addressing this question is one of the issues at the forefront of development of the water industry. The search for a more sustainable management framework has led to the development and promotion of the Triple Bottom Line. However, is this new framework a useable tool or are the reports “greenwash, public relations ploys without substance”?
Cardno MBK’s experience in the development of a Triple Bottom Line Reporting format for one of Queenslands most progressive and environmentally responsible Councils provides an insight into the current state of development of the Triple Bottom Line and provides a contribution toward the development of a practical framework.
Membrane autopsies: helps to provide solutions to operational problems in reverse osmosis plants
Authors: López S. Gallego , del Vigo Pisano F. , Muñoz J. Shang 
Published: May 2018

The problems of the need for water in the quantity and quality for the diverse uses that we require of it is one of the principal problems that we must address. More and more plants are installed for the production of water for potable, irrigation or industrial uses that employ membrane technologies, especially reverse osmosis. Moreover, with increasing frequency these techniques are also being employed in the recycling of waters from urban and industrial effluents.
Paralleling the development of these techniques and their new applications is the need for advances in understanding of the processes that affect their functioning and yield. Any reverse osmosis installation will in the medium or long term encounter problems of membrane fouling that necessitate cleansing. The cleansing protocol depends on the type of deposit (biofilm, organic matter, inorganic deposits or natural colloids) present in the membranes, which makes its characterisation indispensable.
A “membrane autopsy” combines different procedures of analysis and tests capable of revealing information relating to the nature of the deposits and other aspects that can be associated with deficiencies in the functioning of the installations. In this way we have a toolkit able to compile the data necessary for the planning of new guidelines for the management of installations that will minimise or delay the appearance of the problems detected.
Effect of Denitrification on the pH in Biofilms
Authors: Arvin E , Kristensen G H 
Published: May 2018

The experiments in this study have confirmed that the pH inside a denitrifying biofilm may be considerably higher than the pH in the bulk liquid. This has been verified by simultaneous measurements of the pH at the rear of the biofilm and in the bulk liquid. The experiments were performed in a laboratory fixed film unit (rotating drum biofilm reactor).
A mathematical model is developed to describe the pH-profile in the denitrifying biofilm. The predictions made by the model were verified experimentally.
The diffusion coefficients of nitrate, carbon dioxide and bicarbonate were determined to be about 50% of the corresponding values in pure water.
The kinetic experiments performed as part of the verification studies result in kinetic parameter values in agreement with previous findings.
The pH increase is favoured by for example a low alkalinity and a deep active biofilm.
Simultaneous in Situ Determination of Dissolved Gases by Gas Chromatography: II. Oxygen and Nitrogen in Activated Sludge Process Streams
Authors: Bilstad T , Lightfoot E N 
Published: May 2018

A simple, reliable and accurate means for dissolved gas analysis, hitherto used only in clean water, is shown to be suitable for all process streams encountered in activated sludge waste treatment plants. This technique consists of exposing samples of helium across a gas permeable membrane to the solution of interest and determining the amount of each species transferred by standard gas Chromatographic procedures.
The technique appears to be the best available for the analysis of dissolved nitrogen and at least competitive to existing techniques for the measurement of dissolved oxygen. It should be possible to extend its use to any dissolved gas exerting a finite partial pressure.
Nutrients Removal and Recovery in a Two-Stage High-Rate Algal Wastewater Treatment System
Authors: Shelef G , Azov Y , Moraine R 
Published: May 2018

Removal of wastewater borne nutrients by high rate algal ponds for the control of eutrophication in receiving bodies of water was studied under laboratory and outdoor conditions.
Due to limitations of areal productivity and stoichiometry of nitrogen/algal bio-mass and phosphorus/algal biomass only less than 40 percent removal of nitrogen and phosphorus from strong municipal wastewater can be expected through biomass incorporation in one-stage high-rate algae ponds. Nitrogen removal of 74 percent can be attained by supplementary removal through ammonia atmospheric evolution from pond surface while phosphorus removal of 95 percent is attained following algae flocculation with alum. A second-stage pond following a “coarse” algae separation is needed to exert the full incorporation of nutrients into algal biomass. Effluent from the second stage, following “refined” algae separation, contain less than 4 mg/ℓ and less than 0.5 mg/ℓ of nitrogen and phosphorus, respectively. The final second stage effluent sustained reduced further algae productivity even when resupplemented by N and P and only addition of other macro and micro nutrients triggered additional significant algae growth, indicating depletion of algae growth potential factors other than N and P by the preceding two stages. The possibility of recovering the removed nutrient in the form of biomass proteinaceous animal feed is also discussed.
The Influence of Sediment - Water Interactions in an Impoundment on Downstream Water Quality
Authors: Grizzard T J , Randall C W , Jennelle E M 
Published: May 2018

A program of in situ and laboratory studies was conducted in the Southwestern Region of Virginia, U.S.A. to determine the role of the deposited sediments of the Niagara Reservoir in affecting the quality of the flow of the Roanoke River above the headwaters of Smith Mountain Lake. Agronomic analysis techniques were adapted and applied to provide quantitative analysis capability for the sediments. The surficial sediments were observed to constitute a considerable reservoir of phosphorus, which, during the anoxic bottom conditions occurring during the summer months, caused an enhancement of concentrations in the water column. Conversely, during the winter months, the surficial sediments acted as a phosphorus sink, removing it from the water column. Laboratory microcosm studies made it possible to quantify the release and removal of phosphorus under aerobic and anaerobic conditions, and to observe the factors upon which the exchanges depended. The phosphorus interactions were found to be governed principally by sediment iron and organic matter content.
The deposited sediments of Niagara Impoundment showed a capacity to redistribute the impoundment influent nutrient load, causing an enhancement of the quantities released during the summer months, thus magnifying the impact on the waters of Smith Mountain Lake. The maintenance of aerobic benthic conditions could prevent the sediment releases from occurring. In the long term, sediment nutrients deposited in the past, without proper control, could provide a continuing source of phosphorus to the waters of Smith Mountain Lake, thereby reducing the effectiveness of upstream control of point and diffuse sources.
Physical-Chemical Methods of Treatment for Oil-Containing Effluents
Authors: Berné F 
Published: May 2018

After a preliminary oil-removal by gravity in various types of oil-separators, the effluents from pipe-line terminals, de-ballasting units and refineries still contain, as a stable emulsion, significant residual hydrocarbon concentrations, varying from 25 to 300 mgl.
In order to bring these effluents to comply with the regulations governing their discharge either to the sea or to a river, or simply to be able to send them to a complementary biological treatment unit, it is necessary to submit such effluents to a polishing oil-removal process; such process, often called physical-chemical treatment, is necessary to remove the above mentioned residual, insoluble hydrocarbons and leave the soluble hydrocarbons only. Practically and depending on the case considered, the final total hydrocarbon content obtained should not exceed from 5 to 20 mgl−1. For this, there are several techniques based on dissolved air flotation, or filtration. These respective processes and their results are summarized hereafter by the authors who gathered them from experiments conducted on pilot plants and, most of all, from numerous industrial treatment plants in Europe and in America.
Water Pollution Control in Developing Areas: Problems and Needs
Authors: Simpson J R 
Published: May 2018

Wholesome water supplies are essential for the control of many water-related diseases and pathogenic pollution is the most significant type of pollution in developing areas. Thus, the proper handling of wastes is necessary for complete control and data are presented on the fate of pathogens in various environments and waste treatment systems. High kills of pathogens can be achieved during storage in batch composting latrines, aerobic composting windrows and waste stabilisation lagoons.
While water-borne sewerage systems are highly convenient and quickly remove wastes from the immediate environment, they are expensive and sewage treatment is required before disposal. There are satisfactory alternative on-site and off-site excreta handling systems some of which can be adapted progressively as water service levels increase.
The need is stressed for proper training of operators and technicians, the maintenance of plant and the early control of industrial wastes.
Ocean Disposal and Construction with Stabilized Coal Waste Blocks
Authors: Parker Jeffrey H , Woodhead Peter M J , Duedall Iver W , Carleton Herbert R 
Published: May 2018

A multidisciplinary team of scientists at SUNY, Stony Brook is assessing the feasibility of using blocks of waste material from coal fired power plants for underwater construction, including building artificial fishing reefs. Experiments over the past five years, both in the laboratory and in the sea, suggest that coal waste blocks are environmentally acceptable in the ocean.
On September 12, 1980, a 500-ton reef was constructed in the Atlantic, consisting of 15,000 solid blocks of stabilized FGD sludge and fly ash from coal burning power plants. The blocks were fabricated in collaboration with Conversion Systems, Inc. (Horsham, Pennsylvania) at a commercial concrete block plant. In preparation for block fabrication, a combination of different coal waste mixes, stabilization additives, and curing procedures were screened to develop candidate mix designs. Experiments were conducted at research fsei1ities of the Besser Company in Alpena, Michigan to develop methods of successfully forming coal waste blocks with block making machines.
The demonstration disposal reef is being monitored to assess environmental impacts which may occur and their relation to structural integrity and chemical properties of the coal waste blocks. Blocks are tested ultrasonically in the sea and also returned to the laboratory for compressive strength measurements. After almost two years in the sea, gradual increases in strength have been documented.
The progress of biological colonization is also monitored and compared with existing reefs in the area. The fish, benthos, and encrusting organisms are sampled and analyzed for uptake of block components. Data from fish tagging surveys have indicated significant increases in the resident populations of various species of fish and lobster.
Fishery Status and Water Quality in Areas Affected by Acid Deposition
Authors: Howells Gwyneth D 
Published: May 2018

While the relationship of SO2 and NOx emissions to ambient air quality and deposition, and to surface water quality, are still matters for debate and clarification, it is generally recognised that fisheries do not thrive in acid waters. An international advisory commission (EIFAC) has reviewed much of the literature and concluded that below pH 5 progressively more severe effects on fish can be expected. Records of acid lakes in Scandinavia and America show that about 50% of lakes below pH 5 are fishless, compared with only one in seven of similar oligotrophic lakes with pH greater than 5.
However, it is clear that the status of a fishery is not a simple function of the reported pH of a lake or river. Both field and laboratory studies provide evidence that other water quality factors (such as the levels of aluminium and calcium), biological factors (such as food supply, genetically determined tolerance, adaptation), and ecological factors (such as lake morphology, patterns of hydrological events) are also important. How else can we explain the continued presence of fish in some waters well below pH 5?
The paper will present a review of current information from both field and laboratory investigations concerning the responses of fish and fish populations to natural acid conditions in Scandinavian and N. American lakes and rivers, identifying the factors which determine survival and mortality.
The conclusions have some significance for remedial actions that may be proposed to alleviate acid conditions in Scandinavian and N. American waters.
Investigation of an Iodine-Like Taste in Herring from the Baltic Sea
Authors: Bemelmans J M H , den Braber H J A 
Published: May 2018

Marinated herring from the Baltic Sea was found to have an offensive odour and taste described as iodine-like and phenolic. This taint appeared similar to the ‘Jodgeschmack' reported previously in herring. Fat isolated from herring was found to contain this taint. The volatiles were isolated from the fat, using a molecular distillation and were subsequently fractionated by gas chromatography. A fraction containing the taint was obtained and submitted to mass spectrometric analysis to identify compound(s) of interest. By this procedure, the tainted herring was found to be contaminated with o-bromophenol. This compound was not found in good quality herring or only at a concentration level below its odour and flavour threshold values.
The odour and taste thresholds of this compound and its isomers were determined. The thresholds of o-bromophenol were very low, while the character of the taste was in agreement with that of the taint observed in the herring. o-Bromophenol is thus believed to be responsible for the taint. Finally a discussion is given of the various possible sources, which might give rise to the contamination with o-bromophenol. Various bromophenols have been reported in algae, but no monobromophenols. Also, the harvest period of the herring does not correspond to the period that algae are their major food supply. Likely, the iodine-like taint is not associated with the consumption of algae, as has been suggested elsewhere. o-Bromophenol may be an industrial pollutant but is not reported to be used to any extent in industry. However, a trace amount of this compound in the sea can be bioaccumulated to produce this taint. On the other hand, a chemical reaction between bromide and phenol might occur during marination, but no evidence was found to support this.