bluuebunny/crossref_metadata_2025_split huggingface dataset:
3. Design and Construct Contracts in the Water Industry ‐ The Way Ahead? The Consultant's Viewpoint
Authors: GIBSON D. C. 
Published: July 2007

ABSTRACTStages in developing engineering projects within the water industry are reviewed, with particular reference to the construction of wastewater treatment plants by adopting a design and construct approach. This is compared with the involvement of consulting engineers and the more traditional practices. The effect on responsibilities and the influence of the approaches to the management, engineering and outcome of the project are considered.
Groundwater Quality Monitoring in Relation to On‐site Sanitation in Developing Countries
Authors: WARD CATHERINE F. 
Published: July 2007

ABSTRACTGroundwater quality monitoring is considered to be an essential component of any sanitation programme where simultaneous groundwater abstraction and on‐site waste disposal are proposed. The low priority currently accorded to monitoring programmes reflects inexperience of monitoring in general and consequent misconceptions about the content and benefits of groundwater quality monitoring.The purpose of this paper is two‐fold. Firstly to explain why groundwater quality monitoring is a requisite component of all pilot sanitation projects which involve on‐site disposal of human excreta. Secondly, to demonstrate that it is not unrealistic to expect groundwater quality monitoring to be carried out in relation to all such pilot projects.The resource constraints inherent in developing countries need not prohibit routine monitoring. However, it is important to define clearly the specific objectives of any monitoring programme and to design a sampling network appropriate to both these objectives and the site conditions. Monitoring must not be confused with initial assessment of prevailing conditions, nor with research studies, for which the aims, duration, technical complexity, and hence investment, are quite different.Monitoring is a process which can evolve with increased investment to address various questions regarding the causes, nature and processes of groundwater contamination.
Refinements to the BOD Test
Authors: TYERS R. G. , SHAW R. 
Published: July 2007

ABSTRACTFor about eighty years the biochemical oxygen demand (BOD) has remained one of the major indicators of organic pollution in the water industry.Whilst many adaptations and refinements have been made over the last 2–3 decades, one of the most significant was to suppress nitrification by the addition of allylthiourea (ATU) at 0.5 mg/1, thus ensuring that only carbonaceous oxidation was measured. Evidence has accrued to show that, for some situations, this concentration is insufficient to fully suppress nitrification.Poor stability is a problem with biochemical oxygen demand when samples have to be stored prior to analysis, and a method of storage is proposed which minimizes instability. As an empirical bioassay procedure, the accuracy of BOD can be poor compared with alternative methods such as chemical oxygen demand; and problems with incubator and refrigerator temperatures, the preparation of standards, and replacement batteries for dissolved‐oxygen probes are discussed.The aim of this paper is to show that these problems with biochemical oxygen demand can be eliminated, thereby retaining confidence in its use.
Extreme Historical UK Floods and Maximum Flood Estimation
Authors: ACREMAN M. C. 
Published: July 2007

ABSTRACTHistorical flood events recorded as flood marks on bridges and houses or reported in newspapers and journals provide valuable information on the maximum size of floods which are likely to occur in the UK. For hydrological analysis peak water level must be converted to peak discharge, which is problematic even when the flood has been recorded at a flow gauging station. This paper describes some of the methods used to calculate the magnitude of extreme floods. Sixty‐nine historical UK floods are plotted on a graph of discharge versus drainage area and compared with curves published in 1933 and 1960 which were used to estimate the Normal Maximum Flood required for dam spillway design before 1975. From that date the design standard became the Probable Maximum Flood. PMF is calculated for 17 sites where extreme floods have occurred. For six events the observed peak discharge exceeded PMF. Possible reasons for these findings are discussed.
Large‐Scale Biological Nitrate and Ammonia Removal
Authors: ROGALLA F. , RAVARINI P. , LARMINAT G. De , COUTTELLE J. 
Published: July 2007

ABSTRACTIn order to treat water containing nitrogen in excess of the European Drinking Water guideline, an innovative large‐scale biological, nitrogen‐removal process has been used. After extensive pilot‐scale testing and a first full‐scale (80 m3/h) demonstration at Eragny (France), a 400 m3/h installation, serving about 50000 people, was built at Guernes‐Dennemont, near Paris. The raw water source is a combination of percolation from agricultural plains and river bank infiltration, and contains both nitrates and ammonia.The plant consists of two fixed‐bed biological reactors in series. An anoxic filter, using ethanol as a carbon source for heterotrophic bacteria, removes nitrates at filtration rates up to 10 m/h. The denitrified water is then polished on an aerated two‐layer filter, packed with activated carbon and sand. Excess carbon from the first stage, together with reduced nitrogen (ammonia and nitrates), is oxidized at this stage before ozonation of the water.Design data and operational performance are given for total nitrogen (NO3 and NH,), total organic carbon (TOC) and chlorinated hydrocarbons. A specific dosing method for biodegradable carbon was developed to monitor the efficiency of the post‐treatment. Special attention was paid to (a) nitrate control through improved backwash, and (b) reducing the potential for bacterial contamination and aftergrowth in the distribution network.
The EC Bathing Waters Directive as Applied to Scotland
Authors: HALCROW W. , LEATHERLAND T. M. 
Published: July 2007

ABSTRACTSome monitoring of the bacteriological quality of potential bathing waters has been carried out in Scotland since the publication of the EC bathing waters Directive’14 years ago. However, it is only since 1987 that 23 beaches in Scotland have been officially recognized as having bathing waters which should meet the environmental quality standards (EQS) laid down by the Directive. Results of the first three years’monitoring are outlined and the cost of this work has been estimated. The idea of reviewing the standards presently prescribed by the Directive is welcomed. The need to monitor both indicator and target organisms is questioned, and studies are cited suggesting that the present mandatory coliform standards may not be sufficiently stringent. Possible future requirements, including effects of the proposed Directive on the treatment of municipal waste waters, are briefly considered.
Disinfection of Sewage, Stormwater and Final Effluent
Authors: THOMAS VICKY K. , REALEY G. J. , HARRINGTON D. W. 
Published: July 2007

ABSTRACTThis paper highlights the main disinfection options available for sewage, final effluents and stormwater, and is a review of the current research programme being carried out by staff of the Water Research Centre.Disinfection is an increasing requirement, with particular emphasis on bathing and recreational water use. Laboratory and field trials are reviewed, and a wide range of disinfectants have been tested. These include peracetic acid and the Clariflow process for crude sewage; peracetic acid, ozone and UV irradiation for final effluent; and peracetic acid for stormwater.The efficacy of the various disinfectants is evaluated and general costs are presented. Of special interest is the potential effect of sewage strength in reducing the disinfecting properties of the chemical. It is also apparent that there are wide variations in performance between processes and host organisms.
Supervision of Sewers for Adoption
Authors: COX G. C. , BUDLEIGH J. K. , JENKINS W. O. 
Published: July 2007

The Water Authorities Association guide ‘Sewers for Adoption’ has achieved considerable success in unifying practice and establishing well‐understood and recognized standards for the design and construction of sewers by developers under Section 18 of the Public Health Act 1936. However, the supervision provided by the adopting authorities — particularly in relation to supervision fees — has been an area of dispute for some time.The Construction Industry Research and Information Association (CIRIA) has recently completed a study on the optimum levels of supervision for sewer construction. The study included a national survey on the nature and extent of problems occurring during the course of Section 18 work and the supervision practices presently being undertaken. The study puts forward recommendations on the nature and timing of periodic inspections undertaken during construction. Several specific problem areas are discussed, ranging from measures required to ensure that design submissions are of an adequate standard, to the timing of any pre‐adoption closed‐circuit television inspection. This paper draws upon the contents of the report and discusses some of the principal findings and recommendations of the study.
River Flow Simulation: Research and Developments
Authors: KNIGHT D. W. , SAMUELS P. G. , SHIONO K. 
Published: July 2007

ABSTRACTThe translation of recent research work concerning shear layers into practical river simulation models is explained. The equations which govern the lateral distribution of streamwise depth‐averaged velocity are formulated and solved. The analytical solution includes the effects of bed‐generated turbulence, lateral shear turbulence and secondary flows, and therefore reproduces many of the main features of river channel flow. The solution closely simulates the process involved in river gauging by the current‐meter method. Recent data from the Science and Engineering Research Council's Flood Channel Facility are used to illustrate the variation of shear stresses within the flow, and data from three river‐gauging sites are used to illustrate the potential of the model.The steps involved in the design of a modern river simulation package are also described. It is shown how choices made during the development of a model can have a significant impact on the success of model simulations. The development of a package requires many different skills, including those of engineering, mathematics and computing.
Sheep‐Dips as a Source of Pollution of Freshwaters – A Study in Grampian Region
Authors: LITTLEJOHN J. W. , MELVIN M. A. L. 
Published: July 2007

AbstractThe results of organochlorine insecticide analysis of samples taken during 1984–85 from the River Ugie and its tributaries in Grampian Region showed, by the timing and the nature of the compounds found, that sheep‐dips were likely sources of pollution of freshwaters in the Region. Subsequent investigation of freshwaters and treated waters for organophosphorus insecticides typical of sheep‐dips supports this hypothesis. However, there is no evidence of serious contamination of freshwaters in the Region by phenolic compounds from sheep‐dips, even though these are present at high concentrations in sheep‐dip preparations.
Design and Construction of Bulk Storage Reservoirs – Muna, Saudi Arabia
Authors: SLEIMAN B. F. 
Published: July 2007

AbstractThe paper describes the background for, and the magnitude of, the unusual peak water demand (during the Haj season) in Muna and the Holy Environs of Makkah. It then summarizes the various conceptual designs of storage alternatives, which led to the selection of the ‘bulk storage’concept at high elevations in the surrounding hills, commanding the project area by gravity.The objectives of the scheme were (a) elimination of operational and maintenance requirements during the peak demand season, (b) reduction of construction costs, and (c) aesthetic harmony with the surrounding environment.A detailed description of the design of all the components of the two reservoirs covers: location, shape, dam section, flood protection, pipeworks, roof structure, and waterproofing, as well as the mode of operation.Finally, the paper describes the experience associated with the first commissioning of bulk storage reservoir No. 2, and the measures that were introduced to improve the performance of the water‐proofing membrane utilized in the reservoirs.
Historical Factors and Recent Developments in Wastewater Treatment Management in Japan
Authors: KUBO T. 
Published: July 2007

AbstractJapan has experienced serious water pollution problems, such as Minamata Disease (mercury poisoning) in the 1960s. Since then, comprehensive countermeasures have been implemented including establishment of a legislative framework and environmental water quality (EWQ) standards, enforcement of EWQ standards on dischargers, encouragement in the development of sewerage systems, research and technology development, and wastewater reclamation and reuse. This paper reviews the recent developments in wastewater management in this social context in Japan.
Identification, Investigation and Assessment of Contaminated Land
Authors: SMITH M. A. 
Published: July 2007

AbstractThe identification of contaminated land and its associated problems is a multi‐stage process covering the first suspicion of contamination through to the final assessment in which hazards and risks are determined so that appropriate remedial measures can be taken. In the UK, an effort has always been made to distinguish between the existence of ‘contamination’, and any assumption that this automatically implies the existence of a ‘problem’. The task is to identify contaminated land which might currently, or in the future, pose a threat to (a) human welfare, (b) the environment, or (c) natural resources. This can be achieved through an appropriately designed site investigation and subsequent careful assessment of the results.This paper is intended as a broad look at identification, investigation, and assessment processes.
How the Wastewater Discharge Fee Might Become a Tool of River‐Basin Management
Authors: H.K. R. IMHOFF E. 
Published: July 2007

ABSTRACTThe Federal German Water Law of 1976 postulated for the first time that a licence for the discharge of wastewater into public watercourses might only be granted when the wastewater, prior to discharge, is treated according to laid‐down standards. In 1976 it was also decided that for the residual pollution load in sewage‐treatment plant effluents a pollution fee has to be paid.At present three pollution units have to be paid per capita and annually for untreated domestic wastewater. One pollution unit is assessed at 17/annum, but the price will be increased to 30/annum in future.Since the pollution units encompass COD, nitrogen, phosphorus, heavy metals, and chlorinated hydrocarbon compounds, the pollution unit is a good tool to compare the effectiveness of treatment. For different drainage systems the residual pollution units (per litre and second) can also be calculated for low‐flow conditions.
Water Resources and Management in the Republic of Ireland
Authors: McCUMISKEY L. M. , TONER P. F. 
Published: July 2007

ABSTRACTIreland is well‐endowed with water resources and has one of the higher rates of water availability in Europe. However, regional variations in rainfall and population distribution give much less favourable conditions in the east of the country compared to other areas. Pollution of waters to date has been generally localized and moderate in intensity, although there is a trend towards eutrophication of the river systems. Piped water supplies, either from public or private schemes, are now available to nearly all dwellings in the state, both urban and rural. The same position holds for sewerage facilities in the urban areas, but nearly 25% of the rural population is still unserviced in this regard. Future development of services will place more emphasis on sewerage facilities, as outlined in the recently issued national action programme on the environment.
Impact in Scotland of UK and EC Sewage Legislation
Authors: ANDERSON T. A. 
Published: July 2007

ABSTRACTThe EC Directive (91/271/EEC) concerning urban waste water treatment has far‐reaching financial and technological implications for local authorities in Scotland which are responsible for sewerage. Increased capital consent limits and additional financial assistance from central government are essential if the requirements of the legislation are to be met.Although the Directive is welcomed in general terms, the sections of the legislation dealing with the identification of sensitive waters and the provision of primary treatment for coastal discharges to less sensitive waters are of limited environmental significance in Scotland.The elimination of sewage sludge disposal at sea will create severe difficulties for Scottish authorities as a high percentage of sewage sludge is currently disposed of at sea. Each of the main alternative disposal options presents environmental, financial and technical problems and, in the case of incineration, the certainty of widespread unpopularity with the public.
Drinking Water Quality and the Consumer
Authors: FAWELL J. K. , MILLER D. G. 
Published: July 2007

ABSTRACTPublic understanding of water quality is obtained primarily from the extensive media coverage of problems. This has contributed to a distrust of the water supply industry and of specific experts in this field. It is therefore important that the basis of standards for both microbiological and chemical parameters is absoulutely clear and scientifically defensible, since these are the yardsticks against which quality and safety will be judged. They are also the reference point from which political decisions on standards must be made.It is also important that the public is given some understanding of the comparative risks involved and that a proper balance is struck between maintaining microbiological quality and achieving chemical standards, particularly for disinfection by‐products. Without this, the demand for more stringent standards in a search for absolute safety will result in more costly water, while standards approach the unachievable.
Development On and Adjacent to Landfill
Authors: CARD G. B. 
Published: July 2007

ABSTRACTThis paper outlines the engineering design philosophy for development sites affected by landfill gas. The hazards of landfill gas need to be fully understood and evaluated in relation to the location and type of building structure proposed, and a comprehensive assessment and design process should be undertaken. This involves interpretation of investigation and monitoring data, prediction of future trends, selection of appropriate design parameters, evaluation of gas‐control measures, safety during construction, and long‐term serviceability and monitoring.A description is given of the principal types of gas control measures which allow building development to take place on sites affected by landfill gas, and guidance is provided for the design of such measures. These measures include site encapsulation, gas‐venting trenches and wells, gas‐resistant membranes and barriers, natural ventilation to structures, and gas‐detection and management systems.
Groundwater Pollution in Spain: General Aspects
Authors: CUSTODIO E. 
Published: July 2007

ABSTRACTIn spite of many aquifers still being in good condition, groundwater pollution is becoming a serious problem in some areas of continental and insular Spain, although it is not always recognized. Irrigated agriculture is an important source of pollutants, but industrial, mining and urban‐related problems also exist. These go in parallel with serious salinity problems of diverse origin. The degree of knowledge with regard to these problems is still poor, and in many instances low priority is given to studies, prevention, control and remedial action. Water quantity aspects still receive most of the attention and economic resources. A new Water Act includes provisions for dealing with groundwater quality and pollution; they seem adequate to cope with existing problems, but their effectiveness, feasibility and willingness to be applied is still uncertain. The success not only depends on scientific and technical issues, but mainly in achieving an administration and management structure capable of coping with real problems and able to obtain the trust and cooperation of water users.
Denitrification of Wastewater: Operating Experiences in the US and Pilot‐Plant Studies in the UK
Authors: (Fellow) J. UPTON , FERGUSSON ALISON , SAVAGE S. 
Published: July 2007

AbstractDue to the EC urban wastewater treatment Directive, considerable attention has been focused on nitrogen removal, particularly from biological filter nitrified effluents. The paper presents a reliable and proven full‐scale fixed‐film denitrification system installed in the US and evaluated on pilot scale by Severn Trent Water. Methanol has been used as a carbon source dosed prior to the deep‐bed sand filter. The filter removes considerable suspended solids as well as providing the hydraulic retention and surface area for the growth of the biological denitrifying bacteria. Flow sheets of typical US installations are given and operational data with costs are presented for the pilot‐plant evaluation.
The Seaton Carew Sewerage Scheme: Design Features and Contractual Arrangements
Authors: PRICE A. C. , CLARK S. , ROE M. K. , LLOYD T. C. 
Published: July 2007

AbstractNorthumbrian Water Limited has thirty‐four bathing waters and a substantial investment programme to ensure that these waters meet EC standards by 1995. One project within this overall programme is the Seaton Carew Sewerage Scheme. Seaton Carew lies on the southern edge of Hartlepool which has a population of 95000. The scheme will combine existing flows into new foul and storm‐sewage outfalls. The headworks will incorporate screening, grit removal and pumping stations with substantial measures for odour control. Hydraulic operating regimes using active pump control and passive flume control have been investigated to ensure efficient treatment for a wide range of flows. The onerous design, manufacture and construction programme has required the development of new approaches to procuring the work, whilst maintaining a substantial element of competition. The various programmes have been substantially overlapped to ensure that the scheme is completed by April 1993.
Three‐Stage Treatment of Pennine Waters: The First Five Years
Authors: FRANKLIN B. C. , HUDSON J. A. , WARNETT W. R. , WILSON D. 
Published: July 2007

AbstractThe first full‐size three‐stage water treatment works was built at Blackmoorfoot (near Huddersfield) just over six years ago. The three‐stage treatment process involves flotation, first‐stage filtration and subsequent manganese removal in three distinct stages. The works at Blackmoorfoot has been followed by several others in Yorkshire Water. This paper (a) describes the three‐stage treatment process and its developments, (b) relates the operating experiences of the new works to date, and (c) gives some of the operating costs. The treatment process has been successful in treating upland Pennine waters and, as a result, water quality throughout the area has improved. The paper also shows that the process can be modified where water quality allows. The operating costs of the new process are affected by the economies of scale, but need not be greater than those of the older works which have been replaced.
Investigation of River Flow Failure at Sleaford
Authors: HAWKER P. J. , HARRIES K. J. , OSBORNE N. F. 
Published: July 2007

AbstractThe River Slea through Sleaford is fed by groundwater emanating from the Lincolnshire Limestone. In recent years, the springs have dried up periodically, causing failure of river flow through the town. The Slea is a main feature of the town and, when flowing, a valuable visual amenity. Conversely, when it is not flowing, progressive water quality deterioration in ponded sections reduces the river corridor to an eyesore. The paper describes investigations into the cause of the problem and how to overcome it.