bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Developments in Oxygenation of the Tidal Thames
Authors: LLOYD P. J. , WHITELAND M. R. 
Published: July 2007

ABSTRACTIncreased polluting loads are discharged to the tidal Thames at times of heavy rainfall. This can lead to a rapid decline in dissolved‐oxygen (DO) concentrations, which, on occasions, has resulted in fish mortality. The problem is caused by the cumulative effect of surface runoff, increased flows from sewage‐treatment works, and storm‐sewage discharges from the combined drainage of Inner London.An experimental system of in‐river oxygenation has been operated by Thames Water in order to alleviate the problem. This scheme demonstrated that the river oxygenation concept is viable. There was, however, a need to increase the operating reliability of the plant and to provide extra oxygenation capacity. Thames Water carried out a detailed investigation into the various options prior to the acquisition of a new, purpose‐built, self‐propelled, oxygenation vessel, which was delivered to the River Thames in October 1988.
Pre‐Filtration of Very Highly Turbid Waters Using Pebble Matrix Filtration
Authors: RAJAPAKSE J. P. , IVES K. J. 
Published: July 2007

ABSTRACTAs A SOLUTION to very high turbidity problems associated with slow sand filters, a new pretreatment method has been developed at University College, London. Initial experiments with a model using a bed of fine sand (effective diameter d. = 0.32 mm) demonstrated that maximum loadings on slow sand filters should not exceed 25 mg/1 at a filtration velocity of 0.2 m/h for satisfactory run times (approximately 5 weeks). However, a literature survey revealed that many tropical rivers may carry several hundred (or even a few thousand) milligrammes per litre of suspended solids during monssoon periods. A need for pretreatment methods is therefore obvious.A novel process, called pebble matrix filtration, can protect slow sand filters by reducing the suspended‐solids concentration of monsoon river waters (containing up to 5000 mg/1) to below 25 mg/1. The paper briefly describes the principles lying behind the treatment process of pebble matrix filtration, and suitable operational parameters are given at flow rates of 0.72–1.56 m/h for tested suspended‐solids concentrations of 500, 1000, 2000 and 5000 mg/1 kaolin clay in London tap water, with achieved run times of up to 116 h to head losses not exceeding 1.5 m. Filter cleaning is described by a method called ‘drainage and backwash’.
Comparison of Alternative Operating Modes on the Halifax Activated‐Sludge Plant
Authors: JONES G. A. 
Published: July 2007

AbstractSince 1981 the activated‐sludge plants at Halifax sewage‐treatment works have been operated in the ‘Halifax’mode, which has successfully prevented previous bulking of the activated sludge. The paper describes an investigation of the ‘Halifax’mode; also the ‘Halifax’mode plus a sludge bypass arrangement. Plant performance, sewage flows, and electricity and oxygen usages were monitored. Practical measurements showed that an increase of 65% in peak final settling tank flow rates could be achieved, and up to twice the BOD load could be treated with the assistance of extra oxygen, using the existing Vitox plant. The improved settling tank performance can be explained in terms of the Water Research Centre's mass loading theory.
Design of Sewage‐Treatment Plants in Brisbane, Australia
Authors: LEVER M. L. 
Published: July 2007

AbstractBrisbane City Council provides sewage‐treatment facilities for a population of 800 000, together with industrial effluents having an organic loading equivalent to a further 600 000 people. Three projects are described to illustrate some of the different designs and operating parameters used in Brisbane, where the sewage temperatures range from 18°C to 29°C and stormwater is collected separately. The first project is a 400 000 population equivalent augmentation to a conventional activated‐sludge plant located at Luggage Point. The two other plants have to comply, inter alia, with an effluent standard of 10 mg/l for total nitrogen. This requirement, together with site constraints and an economic evaluation of alternatives, resulted in the selection of the extended‐aeration process incorporating anoxic zones and separate mixing and aeration. These contemporary designs are specific to Brisbane conditions, and are intended to facilitate reliable operation as well as being cost effective.
The Avalon Lakes: An Environmental Opportunity
Authors: NEWMAN A. T. , HAWKER P. J. 
Published: July 2007

AbstractThe Avalon Lakes project was a concept to utilize, as water storage reservoirs, shallow basins left by commercial peat exploitation. There are, however, important nature‐conservation interests in the project area. The proposed scheme ultimately incorporated measures to enhance these and, perhaps unusually for a source development, was broadly supported by conservation groups. The related cost was estimated at £4.2M, or 17% of the overall source works’price.Plans and scientific investigations of the scheme occupied a span of 21 years to 1988. It was eventually abandoned as an option for future water supplies following the restructuring of Wessex Water Authority in preparation for privatization of the water industry. The grounds for terminating the project were substantially concerned with costs, though coloured by lingering apprehension about the consistency of water quality.There is now a greater public awareness of the adverse environmental effects of water resource developments. It is suggested that this will lead to future schemes, less obviously suited to their surroundings than Avalon, incurring a higher conservation‐related cost in order to gain acceptance.
Design and Construction of the New Bintulu Water Supply, Sarawak, Malaysia
Authors: LAWSON J. D. , BRYANT D. A. W. , HUANG P. WONG HUNG 
Published: July 2007

AbstractThe new Bintulu water supply was built in the early 1980s to serve a major development of the town of Bintulu in Sarawak, East Malaysia, arising from the extraction of natural gas from the South China Sea. The water supply was designed to supply 78 Ml/d. The works comprise earth dams forming a pumped storage reservoir, a river intake, pumping stations, pipelines, a water‐treatment works, treated water storage and a distribution system. The treatment works and distribution system are being built in two phases. The first phase was completed in 1983, and the second phase is to be constructed in 1990–91.The paper describes the initial planning of the scheme, including water‐demand forecasts, the design and construction of the Phase I works, and problems encountered during its operation. It also highlights the exceptionally rapid implementation programme and stability problems at the main earth dam.
The Blashford Lakes Water Supply Scheme
Authors: EASTWOOD J. C. , ELDER A. J. , PEARSON N. 
Published: July 2007

AbstractWessex Water has developed a new 35 Ml/d water supply source, using lakes formed from worked‐out gravel pits, to meet increasing demands for water and to provide security for existing supplies.Having identified the need for the scheme, an engineering feasibility study was carried out in conjunction with a full environmental assessment. This led to the successful promotion of the Stage I scheme in 1986. Design and construction took place immediately after, and the scheme was officially opened in 1989.There are opportunities to expand the scheme as more lakes are formed by gravel working, and proposals for this are well advanced. This paper describes all the key elements in the promotion and development of the scheme.
The Wastewater Disposal System of the City of Yokohama, Japan
Authors: MIYAKOSHI S. 
Published: July 2007

AbstractModern sewerage system construction in the City of Yokohama dates from 1950. During the ensuing years, the City actively promoted such construction. The first sewage‐treatment plant was commissioned in 1962, and the City's percentage of sewered population (including treatment services) reached 85% in March 1990.This paper describes the outstanding development and record of the wastewater disposal system in Yokohama (which must be ranked ahead of other Japanese cities in this area), as well as the organization, technology, administrative and financing efforts that made this development possible. It also explains the notable features of these works, which include Japan's first fully‐fledged centralized sludge treatment, improvement of combined sewerage systems, industrial effluent control, effective use of sewage effluent and sludge, and sewer user charges. In addition, it presents comments on the future tasks for the 21st century, including advanced wastewater treatment and the integrated information system on water environment.
Coping with COPA II: Actions to Improve Effluent Quality
Authors: BLACK D. W. , FINDLAY G. E. 
Published: July 2007

AbstractThe paper outlines some of the actions taken by Severn Trent Water to achieve compliance with consent limits since the implementation of the Control of Pollution Act (Part II) in 1985.Prior to and since 1985, Severn Trent Water has undertaken an extensive programme to analyse the reasons for failure and carry out remedial work. A major feature of this programme, which has been further stimulated by privatization, has been the need to reduce the lead time for carrying out improvements.The paper discusses the means by which this has been achieved, including the introduction of the ‘fast‐track’initiative and the ‘process matrix’.Other aspects are outlined including initiatives to develop more robust processes, computerized work scheduling, extensive training programmes and best practice studies.
Estuarine and Coastal Waters: Tenby and Weymouth Case Studies
Authors: NIXON S. C. 
Published: July 2007

AbstractThe use of the sea for sewage disposal has come under increasing scrutiny from the public and from other countries bordering the North Sea. There is a need, therefore, to understand and quantify the environmental impact of sewage discharges from long sea outfalls. Broad‐based environmental surveys were carried out at case‐study outfalls at Tenby and Weymouth over a four‐year period. Studies included (a) sediment sampling on coarse grids and near‐outfall transects, (b) bioassays on mussel scope‐for‐growth and Microtox, and (c) uptake of taint compounds.Although at both Weymouth and Tenby the whole survey area was affected to some extent by sewage‐derived material, both outfalls were operating within the dispersive and assimilative capacities of the environment, and thus were having minimal effect. The studies indicated that well‐designed and operated long sea outfalls appear to be an acceptable means of domestic waste disposal.
The Occurrence of Coliform Bacteria in the Surface Soils of Two Catchment Areas in the Yorkshire Dales
Authors: HUNTER C. , McDONALD A. 
Published: July 2007

AbstractThe levels of total coliform and Escherichia coli bacteria were determined within the surface soils of two upland catchments in North Yorkshire. The results indicated that enteric bacteria can survive for a sufficient period outside parent faecal material to provide a semi‐permanent land store that might then be capable of contaminating upland waters following transport by hydrological processes. Significant differences in bacterial counts were found between broadly wet and dry soil moisture/vegetation zones in both catchments. This was explained by the more favourable survival conditions found where the soil moisture content was high enough to prevent the rapid desiccation and death of enteric bacteria. Significant differences were also found between the counts of total coliform and Escherichia coli bacteria in surface soils. It was concluded that the use of the total coliform group alone, as an indicator of the degree of sanitary bacterial contamination of soils, may over‐estimate the true extent of contamination.
Developments in Health‐Related Quality Standards for Chemicals in Drinking Water
Authors: FAWELL J. K. 
Published: July 2007

AbstractSmall differences in water quality standards can mean huge differences in costs for water treatment; difficulties which are compounded by standards for which the derivation is unclear, such as the EC drinking water Directive. Such situations give no indication of the margin of safety for a parameter or the significance to consumers of exceedances. The WHO Guidelines are being revised and will be presented so that the precise derivation of the numbers is absolutely clear. The scientific and quasi‐scientific considerations can be separated and the user given the appropriate information to adapt the guidelines to particular circumstances. In deriving standards for toxicological data the factors incorporated reflect uncertainties in the data and extrapolation from animals to man. Understanding the mechanisms of toxicity or carcinogenicity can reduce the uncertainty and improve the quality of the standard, often allowing higher figures to be used with confidence that public health will not be comprised.
The Development of a Control Policy for Fish Farming
Authors: SMITH H. , HAIG A. J. N. 
Published: July 2007

AbstractThe polluting effects of fish farming have been well‐documented, but the scale of the problem and the difficulty in effectively controlling the industry are less well known. In approximately twenty years, production by this industry in Scotland has increased by two orders of magnitude and it has been estimated that the population equivalent of fish farming effluents is as high as 1.5 million.The development of a pollution control policy for both land‐based and floating‐cage farms is described. The role of other controlling agencies is discussed and legislative weaknesses are identified. In addition, the industry's reaction to pollution control is highlighted.Polluting discharges are not controlled only through the issuing of consents, but effective monitoring is also required. Resource constraints resulted in a policy which includes the requirement of certain fish farmers to self‐monitor their activities.
The Roadford Scheme: Minimizing Environmental Impact on Affected Catchments
Authors: LAWSON J. D. , SAMBROOK H. T. , SOLOMON D. J. , WEILDING G. 
Published: July 2007

AbstractRoadford reservoir, located in the River Tamar catchment and commissioned in 1989, operates in conjunction with two other reservoirs and increased abstraction from six rivers in North and South Devon. The scheme affects the flow regime in all rivers, as well as their water quality, ecology and, particularly, their important salmon and sea trout fisheries. The paper describes how the detailed operating rules for the scheme have been designed to minimize the impact on the environment by means of changes to the flow regime, without jeopardizing the yield of the scheme. The complex operating rules include the zoning of the reservoir storage, varying prescribed minimum flows, spate sparing rules, and special releases for fisheries purposes. A programme of environmental monitoring will allow further refinement of the operating rules.
Groundwater Pollution Arising from the Disposal of Creosote Waste
Authors: ARVIN E. , FLYVBJERG J. 
Published: July 2007

ABSTRACTCreosote‐contaminated groundwater contains a complex mixture of phenols, aromatic hydrocarbons and nitrogen‐, sulphur‐ or oxygen‐containing heterocyclic, aromatic compounds. One of the most important factors that limits the spreading of these contaminants in groundwater aquifers is degradation by subsurface micro‐organisms.This paper gives an overview of the present knowledge about microbial degradation of creosote contaminants under aerobic and anaerobic conditions. Furthermore, various techniques for biological remediation of creosote‐contaminated groundwater are outlined. These techniques include enhancement of the native population of subsurface micro‐organisms to degrade the contaminants (in situ treatment) and withdrawal of the groundwater followed by treatment by various wastewater treatment processes (above‐ground treatment).
Approaches to the Assessment and Remediation of Polluted Land in Europe and America
Authors: GRIFFITHS C. M. , BOARD N. P. 
Published: July 2007

ABSTRACTThe approach to the investigation of contamination is similar in both Europe and North America. However, the assessment of the resultant data can and does vary significantly. This paper seeks to address the concepts employed in contamination assessment in the UK, mainland Europe, Canada and the US. Details are presented of the relevant legislation in each country and the governmental guidance which is issued. Comparisons are made of the approach to the assessment and remediation that would be adopted for sites with identified levels of chemical contamination. The paper also looks forward and expresses views on how the approaches may progress over the next five years.
The Protection of Urban Groundwater from Pollution
Authors: LERNER D. N. , TELLAM J. H. 
Published: July 2007

ABSTRACTThe serious pollution of groundwater under cities is demonstrated with data from Coventry (UK), Madras (India) and Birmingham (UK). Microbiological organisms, nitrates, and organic chemicals are common, but many other pollutants are also found. The main sources are industry and inadequate sewerage. The provision of sewerage must remain a priority, on health grounds, for cities in the developing world. Virtually all industrial sites pollute the soil and groundwater through careless handling of chemicals. Industrial sites should be treated like landfills: contained and carefully monitored. If industrialists had to use groundwater from below their own sites, they would suffer the consequences of any pollution. This would also clean up the aquifer by pumping out polluted water.
Practical Aspects of Yield Investigations of Groundwater Sources
Authors: GROUT M. W. , ALEXANDER D. W. , SIMPSON R. J. 
Published: July 2007

ABSTRACTLee Valley Water plc has, in a joint study with the University of Birmingham, been reassessing the reliable yields of its existing chalk sources in order to make maximum use of the available groundwater resources. An approach to yield assessment was developed which took into account the hydrogeology and flow processes in the vicinity of pumping stations, and within the contributing area. The yield of many sources was found to be very dependent on regional water level conditions. Initial estimates of potential yields were made but future monitoring should aim to clarify the interrelationship between source output and aquifer state.
Impacts of Climatic Change on River Flow Regimes in the UK
Authors: ARNELL N. W. 
Published: July 2007

ABSTRACTMuch has been written in recent years about the potential threats posed by increasing greenhouse gas concentrations. This paper summarizes the implications of global warming for hydrological processes in general and river flow characteristics in the UK in particular, emphasizing the present high degree of uncertainty. Current climate change scenarios for the UK imply that rainfall between autumn and spring will increase, and this may have beneficial implications for UK water resources. However, the effect of this increase may be outweighed by higher evapotranspiration. Average annual runoff in a catchment in southern UK may be reduced by around 5% by the middle of the next century, but this estimate is very uncertain: runoff may reduce by 30% or increase by 30%. Runoff in northern and western UK is likely to show a slight increase (but with similarly large confidence intervals). It is probable that river flows in the UK will be much more concentrated in winter than at present. The effect of a given climate change scenario on monthly flow regimes depends on the current summer water balance and on catchment geological conditions.
The Translocation of Some Herbicides between Soil and Water in a Small Catchment
Authors: MATTHIESSEN P. , ALLCHIN C. , WILLIAMS R. J. , BIRD S. C. , BROOKE D. , GLENDINNING P. J. 
Published: July 2007

ABSTRACTThis paper presents data on the distribution of four herbicides within an agricultural catchment. In the case of mecoprop, 2,4‐dichlorophenoxyacetic acid and simazine, these data include concentrations in the soil, field drains and the stream, before and after applications of the herbicides following good agricultural practice. The concentrations of these herbicides in the soil were found to follow published degradation rates, and their concentrations in the stream and drains were elevated following rainfall with peak concentrations from 0.12 μg/1 to 68.0 μg/1. Atrazine was found at relatively high concentrations (peak 122 μg/1) when it had not been applied to any of the fields draining to the sampling point.The data will be used to test models that may be used as one of a number of tools for the screening of new pesticides prior to their registration. One approach using the Mackay's fugacity model is outlined.
Sewage Sludge Disposal in the UK: A New Challenge for the Next Twenty Years (Abridged)
Authors: MATTHEWS P. J. 
Published: July 2007

ABSTRACTThe paper attempts to review current and future practices in the UK against a European background.Sludge disposal has become a subject which is developing rapidly again and, since the presentation of this paper, there have been a number of developments, e.g. the adoption by the EC of its hazardous waste Directive in December 1991. Untreated sludge or sludge which is unsuitable for use in agriculture will be classified as a hazardous waste, subject to certain criteria. This makes the work on sludge classification even more crucial.
The Management and Creation of Beaches for Coastal Defence
Authors: RIDDELL K. J. , YOUNG S. W. 
Published: July 2007

ABSTRACTThe creation and management of beaches using natural mobile materials can often provide a cost‐effective and environmentally appropriate coastal defence. This paper summarizes recent practical endeavours in beach creation and management. Reference is made to the natural sources of beach building materials and to the numerical and physical models that may be employed to assist in the definition both of material transport paths and their magnitude. Risk analysis is noted to be a necessary part of the beach design process together with an appraisal of the coastal hydrodynamics and topographical constraints of the site of interest. The techniques that have been employed to recycle beach materials on some frontages are described, with comments on bypassing materials around obstructions. The paper describes the important considerations to be made when material is being imported to a beach, and notes some of the presently used techniques. Important points are drawn out for the future of beach creation and management, and a number of research needs and administrative difficulties are highlighted.
Asset Management Planning: Theory and Practice
Authors: LINDLEY E. 
Published: July 2007

ABSTRACTIn 1988, water undertakers in England and Wales were charged with producing asset management plans as a prelude to privatization. These plans had to provide an auditable statement with respect to the condition and performance of underground assets, with a view to defining and setting priorities for investment requirements.Some water authorities were ill‐prepared for producing the required formalized plans, resulting in variable confidence limits being placed on the identified investment requirements. A need existed to refine most plans, which was reinforced by a statutory requirement to update the asset management plans.This paper deals particularly with water distribution systems and provides an insight into the production of asset management plans. A brief review of the current approach used by a certain major water plc, to update and refine their plans, is also included. The contribution of asset management plans to the effective management of distribution network investment and operation in England and Wales should not be underestimated and is equally relevant in Scotland.