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91.
92.
The fens of eastern England rely on flood defences for their existence, and planning for flood risk has always had a high priority. A new focus was given with the issue of Planning Policy Guidance 25, and this paper presents experience from a Strategic Flood Risk Assessment of South Holland District, in Lincolnshire. The assessment pioneered the examination of fenland flood risk in terms of risk zones related to flood hazard and standard of protection. Methods for evaluating the risk zones are described; they consider flooding from embanked rivers which are subject to tide locking, internal drainage systems, tide level and wave action. The methods would be appropriate for many lowland areas of the UK where conventional flood analysis cannot be used. 相似文献
93.
E. KOCIANOVA MSc Ing R. J. FOOT C. F. FORSTER BSc PhD CE FIChemE 《Water and Environment Journal》1992,6(4):342-350
The presence of stable foams can seriously impair the ability of an activated sludge to produce a high-quality effluent. This paper examines how the physicochemical characteristics of the solids are related to foam formation and describes how the foaming potential of full-scale plants can be assessed. It also confirms that Microthrix parvicella can exhibit a variable morphology and shows that these variations are related to the physicochemical properties that characterize foam-forming solids. 相似文献
94.
T. S. C. GROSS BSc CEng DipEM MICE M. K. DAVIS BSc CEng MICE 《Water and Environment Journal》1991,5(6):649-658
In March 1990 a pilot ultra-violet disinfection plant was installed at the sewage-treatment works in Bellozanne, Jersey. The pilot plant was set up to test the ability of the process to meet certain defined objectives and, ultimately, to enable the island authorities to satisfy stringent water quality objectives in the receiving waters of St Aubins Bay.
The pilot study simulated an open channel installation using medium pressure ultra-violet lamps parallel to the direction of flow. The pilot plant was supplied by Trojan Technologies Inc.
The pilot study met its objectives and confirmed the design parameters for a full-scale plant installation to follow. 相似文献
The pilot study simulated an open channel installation using medium pressure ultra-violet lamps parallel to the direction of flow. The pilot plant was supplied by Trojan Technologies Inc.
The pilot study met its objectives and confirmed the design parameters for a full-scale plant installation to follow. 相似文献
95.
The Development and Application of Phosphorus Removal from Wastewater using Biological and Metal Precipitation Techniques 总被引:1,自引:0,他引:1
The paper describes a programme of technology development in phosphate removal which was carried out by Anglian Water in response to the requirements of the urban waste water treatment Directive Trials covered pilot and large-scale biological nutrient-removal plants, and iron-salt dosing to activated-sludge plants and biological filters. The fundamentals of the processes are discussed and results are presented. 相似文献
96.
Models are being used extensively to study the impact on the environment of a wide range of man-made influences. These include land-use change (e.g. afforestation), effluent discharges, flood-relief channels, reservoir developments, atmospheric pollution and the impacts of agrochemicals. In this paper several models are described which are being used by the Institute of Hydrology for environmental impact assessment. These models include MAGIC (Model of Acidification of Groundwater in Catchments), QUASAR (Quality Simulation Along Rivers) and a nitrogen simulation model for investigating the behaviour of nitrate in reservoirs. 相似文献
97.
This paper describes research in areas where the occasional failure to meet the EC standard for lead in drinking water is due to the presence of particulate lead. A method is described to disinguish between soluble, particulate and colloidal lead in tap water, and characteristics are given of water sources which are most likely to suffer from this form of lead problem. At least two types of particulate (insoluble) lead in tap water have been identified, and some factors are discussed which cause the occurrence of both types. Interim results of trials are presented, with remedial actions. 相似文献
98.
99.
J. GAY BSc MS CEng MICE R. WEBSTER BA MSc D. ROBERTS BA MSc M. TRETT BSc FLS 《Water and Environment Journal》1991,5(5):573-580
The environmental implications of implementing the requirement for treatment of coastal sewage prior to discharge, which were put forward in an EC draft Directive on municipal waste-water treatment, are examined. In order to establish the current situation, the results of a national survey of coastal and estuarine sewage discharges are presented. A review of the impact of sewage discharges on the marine environment is presented in conjunction with an assessment of the impact of sewage-treatment processes on the land and in the air. These aspects are integrated into overall conclusions about net environmental impact. Finally, a decision-tree approach to the assignment of priority to additional action required at individual locations is developed. 相似文献
100.
Richenda K Connell BSc DPhil Robert Willows BA PhD Jacquelyn Harman BSc MSc Stephen Merrett BA MPhil D.Lit 《Water and Environment Journal》2005,19(4):352-360
Climate risk management is a new and evolving area and many decisions are likely to be affected by climate risks over the long-term. This paper presents a decision-making framework designed for managing climate alongside nonclimate risk factors. The framework describes a process that should help identify and manage these risks. It can be used to help decision-makers answer questions about whether adaptation is required, and, if so, which measures should be implemented. Adaptive management is recommended as a useful approach for dealing with climate and other uncertainties. This paper describes an application of the framework to a water resources case study. Feedback from training workshops based on four different case studies suggests the framework provides at minimum a useful (post-hoc) decision analysis tool. Potential users, who include planners, consultants and policy-makers have been largely positive about the prospective utility of the framework. 相似文献