bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contingent Valuation of First‐Time Sewerage Provision in South‐East England
Authors: McMahon P. , Moran D. , Sutherland P. , Simmonds C. 
Published: July 2007

AbstractSection 101A of the Water Industry Act 1991 requires that sewerage undertakers provide a public sewer to replace private wastewater systems if certain conditions are met. These include identification of pollution and amenity problems attributable to the private systems and economic justification of public sewer provision. Economic justification necessitates that the costs and the benefits of public sewer provision are compared. An environmental valuation study, using the contingent valuation method, has been carried out in three locations in south‐east England to provide the average monetary value of the benefits accruing to households with unsatisfactory private systems. A statistical analysis of the survey‐response data has yielded a monetary value which can be used in the assessment of the benefits of first‐time public sewerage schemes.
Some Hydrogeological Peculiar to Various Types of Problems Small Islands
Authors: Robins N. S. , Lawrence A. R. 
Published: July 2007

AbstractThere are many problems associated with the investigation of small island hydrogeology, including (i) the availability of data and the distribution of both spatial and temporal data sets, (ii) the dynamics of the groundwater to sea‐water interface and the shape of the so‐called groundwater lens, and (iii) the difficulties of evaluating recharge to groundwater and of calculating the volume of groundwater discharge to the sea. These issues are compounded by (a) the ratio of coast to area in small islands, (b) the problems of extreme topography, and (c) the identification of baseflow to rivers and streams. A simple classification of island types assists in evaluating hydro‐geological regimes, and the importance of groundwater in an island context cannot be over‐emphasised.
Easter 1998 Floods
Authors: Horner M. W. , Walsh P. D. 
Published: July 2007

AbstractPrior to Easter 1998, the 1947 floods were the reference events for flood‐risk management in many catchments throughout England and Wales. However, Easter flood levels were generally higher than those of 1947 in the river systems draining an area of about 5000 km2, bounded by Bedford in the east, Evesham in the west, Peterborough in the north, and Oxford in the south.The paper describes the background to the floods and the independent review, and outlines the lessons which emerged from the Easter 1998 flood experiences, particularly in relation to flood‐plain management, hydrometry and flood forecasting and warning.
Evaluation of a Pilot‐Scale Bioscrubber for the Removal of Hydrogen Sulphide
Authors: Koe L. C. C. , Yang F. 
Published: July 2007

AbstractThis technical note describes an investigation on the feasibility of using treated wastewater to support the operation of a fixed‐film bioscrubber for H2S removal. A laboratory‐scale fixed‐film bioscrubber was assembled using Thiobacillus bacteria which were isolated from a sample of raw sludge, cultured in the laboratory, and immobilised onto the scrubber's plastic packing media by an immersion method.
Flow Requirements of Spawning Atlantic Salmon in an Upland Stream: Implications for Water‐Resource Management
Authors: Webb J. H. , Gibbins C. N. , Moir H. , Soulsby C. 
Published: July 2007

AbstractThe spawning sites selected by female Atlantic salmon (Salmo salar) were surveyed over three consecutive years in the Girnock Burn, Aberdeenshire, Scotland. Discharge was calculated for each spawning site to assess within‐catchment variation in spawning discharge selection. In total, 428 incidents of female spawning activity were logged at 48 sites. Fish selected relatively high flows in which to spawn, with the lowest utilised discharge being equivalent to the burn's 50 percentile flow.The results emphasise the importance of relatively high flows during the spawning season and, more specifically, a range of flows which ensures that sites are distributed as widely as possible and are accessible and suitable.
Environmental Performance Indicators: The Water Industry of England and Wales
Authors: Johnston A. , Smith A. 
Published: July 2007

AbstractWater companies in England and Wales produce reports using environmental performance indicators which have been developed in‐house. However, there is no recognised methodology for the development of these indicators, and an analysis of available guidance led to the proposal of an appropriate model. This model was tested by semi‐structured interviews of water‐company managers, and a questionnaire was completed by managers from other industries. The responses from the interviews supported the inclusive, quality‐driven approach advocated by the model, and indicated a need to examine (a) the style of management, (b) the staffing structure in water companies, (c) the connection between environmental management systems and indicator development, (d) types of objectives and targets, and (e) the use of indicators as public‐relations tools. The result is a methodology for indicator development which can be applied by managers in industry.
Potential Endocrine Disrupting Substances from Materials in Contact with Drinking Water
Authors: Fawell J. K. , Chipman J. K. 
Published: July 2007

AbstractAt present, there is much interest in the potential effects of chemicals on the endocrine systems in animals and man. Chemicals with endocrine‐disrupting potential include (a) various phthalates, (b) compounds based on bisphenol A and F, (c) compounds based on alkyl phenols, and (d) the antioxidant butylated hydroxyanisole. However, the potency of these chemicals in comparison with natural hormones appears to be very low. Although there is some evidence for activity in animals, high doses are usually necessary, and there is controversy and uncertainty in the interpretation of some positive findings. In addition to consideration of potential hazards, the level of exposure through leaching of these chemicals into drinking water is an important component of risk assessment. The present approval processes ensure that such exposure is very low. The paper suggests a strategy for the future continued assurance of an adequate safety margin for human exposure to such substances through drinking water.
The Impact of the Water Framework Directive on Catchment‐ Management Planning in the British Isles (Abridged)
Authors: Williams K. 
Published: July 2007

AbstractThe water framework Directive is proposed as a mechanism for applying river‐basin management across the European Union. Proposals for River‐Basin Management Plans might have an impact on the present system of Local Environment Agency Plans and on schemes which are used in the British Isles to provide river management on a catchment basis. For this study, representatives from the Environment Agency, Scottish Environmental Protection Agency and European Parliament advisors were interviewed. In addition, Local Environment Agency Plans were assessed for compatibility with the requirements of River‐Basin Management Plans.
The Sea‐Defence Value of Salt Marshes: Field Evidence From North Norfolk
Authors: BA I. Möller , Spencer T. , French J. R. , Leggett D. J. , Dixon M. 
Published: July 2007

AbstractApproaches to coastal management have focused increasingly on ‘soft’engineering methods such as beach/foreshore recharge or the managed realignment of coastal defences. In this context, the creation/maintenance of salt marshes is often seen as being of ecological and flood‐defence importance. However, until recently, no field data of wave attenuation over Northern European salt marshes had been available; therefore the debate on the sea‐defence value of salt marshes has remained highly speculative. This paper (a) reviews results from a field and numerical modelling study at Stiffkey, north Norfolk, (b) presents a scientifically based argument for the evaluation of salt marshes as part of sea‐defence schemes, and (c) discusses the relationship between hydrodynamic parameters, salt‐marsh surface characteristics, and possible management implications and engineering guidelines.
Upgrading a Conventional Activated‐Sludge Plant Using a Multi‐Stage Aerobic System with Step Sludge Recirculation
Authors: Palma L. Di , Eng Dr. , Medici F. , Eng Dr. 
Published: July 2007

AbstractThe performance of a multi‐stage activated‐sludge plant with partial biomass recirculation was examined. The system, which was designed to treat domestic sewage, consists of four stages and has two recirculation flows: (a) directly into the anoxic stage, and (b) distributed over all the aerobic stages from the secondary settlement tank. Different values of recirculation flow to each aerobic stage were adopted during the experiments, and the optimal configuration for removing both ammoniaca! nitrogen and carbonaceous substrate was determined. The configuration which gave the best performance also improved the sludge settleability.
Constructed Wetlands for the Treatment of Runoff from the Newbury Bypass
Authors: Pontier H. , May E. , Williams J. B. 
Published: July 2007

AbstractThe A34 Newbury bypass crosses sensitive watercourses and incorporates runoff‐control systems. The series of treatment stages of each system comprises an oil interceptor, silt trap, grassy slope and constructed wetland. In December 1998, a monitoring programme was initiated for one of the systems to evaluate the removal and behaviour of pollutants, and this paper presents the initial results. Future work will examine the mechanisms involved in metal removal and the fate of other pollutants.
Contractual Issues of Process‐Plant Projects
Authors: CEng G. H. Bateman 
Published: July 2007

AbstractThe paper describes the structure of a process‐plant contract and distinguishes it from other forms of design‐and‐construct contracts. The various tests used in process‐plant contracts are highlighted, including performance tests relating to process guarantees and the remedies for failure to achieve such guarantees, with particular reference to the water industry. The differences between price‐based and cost‐based contracts are reviewed, together with three significant areas of contractor's liabilities for design, defects, and overall contract liability. The paper also briefly introduces the development of operation and maintenance contracts and design‐build‐finance‐operate contracts.
The Control of Nitrite Formation in London's Distribution System
Authors: Williams A. M. , Andrews S. , Wakeford P. 
Published: July 2007

AbstractThe formation of nitrite in distribution systems has been understood for a number of years. This paper explains how controls have been developed based upon that knowledge, and how nitrite formation was reduced by 80% over a period of three years, in London's distribution system. Effective control measures and associated procedures included (a) forming process‐optimisation teams, (b) setting realistic targets, and (c) producing a manageable and simple monitoring system ‐ by training and communication, and using simple analytical equipment. Control measures included optimisation of the ammoniation process and increasing the chlorine concentration in the distribution system.
Integrated Lake and Catchment Phosphorus Model ‐A Eutrophication Management Tool. II: Application to Rutland Water
Authors: Daldorph P. W. G. , Spraggs G. E. , Lees M. J. , Wheater H. S. , Chapra S. C. 
Published: July 2007

AbstractAn integrated lake and catchment model was used to simulate reservoir volume and phosphorus concentrations in Rutland Water over a period of seventeen years, taking into account changes in reservoir output and phosphorus sedimentation resulting from the addition of ferric sulphate. Application of the model for critical‐period analysis and the setting of environmental targets and trigger values are discussed, and an example is given showing the impact of changing reservoir output on the frequency distribution of phosphorus using an eighty‐year set of river‐discharge data. The impact of phosphorus removal at point sources in the catchment on phosphorus concentrations in the river and reservoir is simulated and compared to results from SIMCAT ‐ a steady‐state model which was developed by the Environment Agency. Results are also compared with observed data following the implementation of the EC urban waste water treatment Directive, at the end of 1998.
Integrated Monitoring and Modelling of Odours in Sewerage Systems
Authors: Spooner S. B. 
Published: July 2007

AbstractThe parameters of sewage that affect the production and resulting concentration of hydrogen sulphide in both liquid and gas phases have been monitored in a sewerage system. The data have been used to develop a model of the chemical and physical processes leading to sulphide production in sewers, so that the sources and causes of the problem can be identified. This model has been adapted to predict the concentrations of hydrogen sulphide that can be expected in the sewage and sewer atmosphere, following the construction of a major interceptor tunnel.
Construction Risk in Coastal and River Engineering
Authors: Simm J. D. , Camilleri A. J. 
Published: July 2007

AbstractNew methods and protocols are presented to assess and mitigate time, cost, quality and safety risks in construction, based upon the research behind two manuals which have been produced by HR Wallingford under industry guidance. The paper focuses on the specific risks associated with weather, sea and river state conditions. The inter‐relationship with procurement route and insurance is also discussed. A contractor's view of construction risk is then given in the form of a case study based on the Eastbourne Coast Protection Scheme. This scheme involved work on a coastal foreshore in a tidal and marine environment and included five phases of timber groynes, rock revetments, concrete sea‐walls and the reconstruction of promenades plus two phases of shingle renourishment.
Investment Appraisal in the Water Industry of England and Wales
Authors: Tebbutt R. J. , Guy J. A. , Cochin R. J. , Lester J. N. 
Published: July 2007

AbstractSince privatisation in 1989, the changing nature of the water industry in England and Wales has increased the need for effective investment appraisal. Previous research highlighted many aspects of the industry that could detract from the efficacy of conventional discounted cash‐flow techniques, and found that an investment‐appraisal technique must fulfil a number of criteria in order to overcome these difficulties. This paper examines a number of financial and strategic management techniques for investment appraisal, and assesses their suitability with reference to these criteria. It shows that, of the studied techniques, the ‘balanced scorecard’appears to be most suited for use in the water industry of England and Wales.
A Biosolids Composting Challenge: Meeting Demand for a Peat‐Free Horticultural‐Grade Product
Authors: Bowman L. , Durham E. 
Published: July 2007

AbstractIn 1996, Thames Water launched a range of peat‐free compost products based on biosolids. In order to keep up with demand and to maintain the high standards of product quality, the company has investigated higher‐rate composting processes and optimisation of the maturation stage. Agitated‐bay composting systems are the preferred in‐vessel technology for large sludge treatment centres using woodchip as a bulking agent. These automated systems (i) accelerate the composting process, (ii) maximise throughput on a smaller footprint, and (iii) achieve better control of odour emissions.A maturation trial with composted material from the US Filter agitated‐bay system confirmed that a horticultural‐grade product could be attained. Small‐scale maturation trials showed that seeding with mature green waste compost can accelerate nitrification to such a rate that near zero levels of ammonia can be achieved after one month of maturation.
Operating a High‐Rate Digester: The Southern Water Experience
Authors: Brown S. , Sale R. 
Published: July 2007

AbstractSouthern Water has implemented a large capital‐investment programme in order to meet the requirements of the EU Urban Wastewater Treatment Directive. Within Southern Water, the Directive will result in a doubling in the quantity of wastewater sludge to be treated. In order to minimise the amount of sludge to be transported and produce a stabilised sludge which is suitable for recycling to agricultural land, the company's sludge strategy is based on treatment by mesophilic anaerobic digestion.This paper (a) highlights some of the consequences of operating a high‐rate digestion plant, and (b) focuses on areas such as depositions in thickened sludge digester feed lines, the start‐up procedures for high‐rate digesters, foaming, hair and fibre build‐up problems and treatment failure caused by toxicity inhibition. All these problems have been corrected or controlled and have resulted in Southern Water revising and updating its design manuals and standards, to prevent such future difficulties.
The Rio Salado Basin in Argentina: An Integrated Master Plan
Authors: Palmer J. , Suter S. N. , Aradas R. D. 
Published: July 2007

AbstractBeing close to Buenos Aires and with high production levels in the agriculture sector, the Rio Salado basin is an area which has always attracted investment. During the last century, considerable hydraulic drainage and flood‐alleviation works were carried out to increase agricultural production in the region. However, during the last two decades, the catastrophic effects of flooding and the persistence of low agricultural productivity in most of the area, demonstrate that the interventions (which have been made so far) have been inadequate. Perhaps one of the key factors in the lack of success of historic hydraulic interventions has been the absence of a strategic/ integrated approach. This paper describes the first attempt at integrated river‐basin planning in Argentina.
Groundwater Contamination from Rural Pit Latrines: Examples from Siberia and Kosova
Authors: Banks D. , Karnachuk O. V. , Parnachev V. P. , Holden W. , Frengstad B. 
Published: July 2007

AbstractNew hydrogeochemical data from Kosova and southern Siberia agree with previous studies from Botswana and Moldova in suggesting that high densities of pit latrines (and other domestic pollution sources) in rural villages can result in contamination of potable groundwater supplies by microbes and nitrate. Concentrations in excess of 100 mg/l nitrate have been recorded in each of these areas, at which levels small children may be endangered by methaemoglobinaemia. The sanitation and water‐supply conditions are believed to be typical of large areas of Eastern Europe and the former Soviet Union. It is likely that poor sanitation and conflict with potable‐water supplies are among the main sources of environmental risk to populations in these areas, rather than the industrial and military contamination upon which so many international collaborative programmes have focused.
Environmental Implications of Incineration and Other Advanced Sludge‐Treatment Processes
Authors: Davis R. D. , Glennie E. B. , Hobson J. A. , Sivil D. 
Published: July 2007

AbstractIn the UK, there is a strong trend towards more thermal processing of sludge with energy recovery or advanced treatment of sludge, in preparation for use in agriculture or other outlets. This has resulted from (a) the loss of the sea‐disposal outlet and (b) pressure to improve the microbiological quality of recycled biosolids to land. In 1996–97, incineration accounted for 8% of sludge, and this figure is expected to increase to 21% by the year 2005. During this period, the annual production of sludge is expected to increase from 1.12 million tDS to 1.47 million tDS. More sludge will be treated by processes such as thermal drying, thermophilic digestion, prepasteurisation and mesophilic anaerobic digestion, lime treatment and other advanced options such as gasification. These developments apply across the EU and are likely to be driven forward by the impending revision of the ‘sludge to land’Directive. The paper considers the environmental implications of these developments in terms of energy usage and recovery, air and water quality, greenhouse‐gas emissions, effects on contaminants, and the quality of products or residues.
Maintenance of Sludge‐Treatment Plants
Authors: Thompson M. S. 
Published: July 2007

AbstractDuring the last decade, Southern Water has designed, constructed, commissioned and operated a number of large sewage‐treatment works and sludge‐treatment centres. Also, over the last two years, Southern Water Project Delivery has been working closely with Southern Water Operations, to identify and resolve a number of design and operational issues which have arisen at two strategic sludge‐treatment centres, i.e. Canterbury and Goddards Green. The resolution of these issues has been both interesting and technically challenging. The purpose of this paper is to share some of these issues and their resolution.
Developments in Urban Pollution Management
Authors: Clifforde I. , Crabtree B. 
Published: July 2007

AbstractThe paper presents background information about the development of the original edition of the Urban Pollution Management Manual (1994) and gives reasons why the manual was updated relatively soon after initial publication (1998). The latter part of the paper examines three specific issues where the changes between the two editions have proved to be contentious in terms of implementation of the ‘asset management plan 3’programme by the UK water industry, namely: (i) the choice of environmental criteria for protecting river aquatic life; (ii) meeting the requirements for controlling aesthetic pollution; and (iii) the role of simplified modelling in urban pollution management studies. The paper concludes that any increased cost implications for the implementation of the programme are as a result of changes in Environment Agency policy, rather than due to technical changes in procedures.
WATER, SEWERAGE AND DRAINAGE INFRASTRUCTURE FOR PALESTINIAN REFUGEE CAMPS IN LEBANON
Authors: Davey J. C. , Maziliauskas J. 
Published: July 2007

ABSTRACTMany of the Palestinian refugee camps in Lebanon were originally established as tented encampments during the period 1948–1955. Half a century later, with high population densities and limited vehicular access, they remain largely separate from adjacent Lebanese communities, with infrastructure and welfare services mainly provided by the United Nations. Water supply, sewerage and stormwater‐drainage systems have been developed on a piecemeal basis, are frequently in poor condition, and are inadequate to cops with expanding populations. A project for the design of new systems was commissioned to serve a total population of about 250 000 by the year 2020. The new facilities have had to take account of complex networks of narrow pedestrian alleyways that characterise many of the camps.This paper provides an insight into (a) working within established refugee camps and other economically poor and densely populated communities, and (b) the problems which were experienced in developing feasible solutions for the improvement of infrastructure.