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The article announces the recipients of the awards for published papers in the journal from the Institution of Civil Engineers including Baker Medal to Seckin G, Haktanir T., and Knight D.W., and Robert Alfred Carr Prize to Fenner R.A. McFarland G., and Thome O.

In the UK, decision makers use hydraulic model outputs to inform funding, connection consent, adoption of new drainage networks and planning application decisions. Current practice requires the application of design storms to calculate sewer catchment performance metrics such as flood volume, discharge rate and flood count. With flooding incidents occurring more frequently than their designs specify, hydraulic modelling outputs required by practice are questionable. The main focus of this paper is the peakedness factor (ratio of maximum to average rainfall intensity) of design storms, adjudging that this is a key contributor to model bias. Hydraulic models of two UK sewer catchments were simulated under historical storms, design storms and design storms with modified peakedness to test bias in modelling outputs and the effectiveness of peakedness modification in reducing bias. Sustainable drainage systems (SuDS) were implemented at catchment scale and the betterment achieved in the modelling outputs was tested. The proposed design storm modification reduced the bias that occurs when driving hydraulic models using design storms in comparison with historical storms. It is concluded that SuDS benefits are underestimated when using design rainfall because the synthetic rainfall shape prevents infiltration. Thus, SuDS interventions cannot accurately be evaluated by design storms, modified or otherwise. [ABSTRACT FROM AUTHOR]

Abstracts of papers published in the Institute of Civil Engineers (ICE) Proceedings for 2006 in Great Britain are presented. This include the paper "UK Reserviors Face Drought of Safety Engineers," written by I Hope from the November issue. Another is the "Cheong Gye Cheon Restoration in Seoul, Korea," by J.-H. Shin and I.-K. Lee from the November issue. And the "Ethics: Making it the Heart of Water Supply," by M. Sohail and S. Cavill from the May issue.

The article presents abstracts of papers published in the Institution of Civil Engineers (ICE) Proceedings in 2004. They include the "Anderton boat lift: restoring the Cathedral of the Canals", "The breast shot water wheel: design and model tests" and "Evaluation of UK waterway regeneration and restoration".

An introduction is presented for the journal “Water Management" which focuses on publishing research papers for the benefit of engineers working in water management, and talks about the peer-review process, wastewater treatment and re-use of saline drainage water.

This paper reports on the formation of the Flood Risk Management Research Consortium and the research that is under way within the 'towards whole systems modelling' (WSM) priority area. Funding for the consortium is provided from a wide range of research funders in the UK including the national research councils, government departments and agencies with responsibility for flood risk management. The research portfolio has been formulated to address key research needs identified by the funders. This briefing note explains the relationship between the planned research in the WSM area and the UK Environment Agency's Strategy for Flood Risk Management. Additionally, it provides an introduction to the companion research papers in this issue by Villanueva and Wright, Hunter et al., Lin et al., and Néelz et al. The research reported in these companion papers focuses on flood inundation modelling and is an important subset of the work to be undertaken within WSM. [ABSTRACT FROM AUTHOR]

The wider benefits of natural flood management are increasingly used to engage local stakeholders and justify physical implementation. Previous studies have highlighted the potential for upstream natural flood management interventions to contribute to water level management strategies by mitigating downstream water levels and promoting free discharge at surface drainage outfalls from urban areas. The study reported in this paper extended the scope of this possible benefit by examining the potential for upstream interventions to de-synchronise rural and urban responses under various storm tracks, thereby improving the performance of downstream surface drainage networks. The methodology used a coupled modelling approach. Five design events, each applied with eight different storm tracks, were used to evaluate how catchment-scale natural flood management in the upper Calder River, UK, might influence performance of surface drainage in the downstream town of Todmorden. The results suggested that all the storm tracks considered had substantial influence on whether urban rainfall occurs during the period when outfalls are inundated. While upstream natural flood management interventions create modest flow attenuation, a slight delay in rural response can significantly improve drainage performance and reduce instances of nuisance flooding. [ABSTRACT FROM AUTHOR]

This paper presents a new data-driven modelling framework for forecasting probabilistic flood inundation maps for real-time applications. The proposed end-to-end (rainfall–inundation) method combines a suite of machine learning (ML) algorithms to forecast discharge and deliver probabilistic flood inundation maps with a 3 h lead time. To classify wet/dry cells, the method applies rainfall–discharge models based on random forest technique on top of classifiers based on multi-layer perceptron. The hybrid modelling framework was tested using two subsets of data created from an observed fluvial flood event in a small flood-prone town in the UK. The results showed that the model can effectively emulate the outcomes of a hydrodynamic model (Flood Modeller (FM)) with considerably high accuracy measured in terms of flood arrival time error and classification accuracy. The mean arrival time difference between the proposed model and the hydrodynamic model was 1 h 53 min. The classification accuracy was measured against a synthetic aperture radar image, producing accuracies of 88.22% and 86.58% for the proposed data-driven model and FM, respectively. The key features of the proposed modelling framework are that it is simple to implement, detects flooded cells effectively and substantially reduces computational time. [ABSTRACT FROM AUTHOR]

An easy-to-use equation is presented for calculating the variance of a design flood estimated using a generalised logistic distribution with model parameters estimated using single-site analysis, as described in the UK Flood Estimation Handbook. The equation is applicable for return periods in the range 2–1000 years and for annual maximum flood series with L-skewness of −0.45 to 0.45, which is considered representative of most UK flood data and practical uses. [ABSTRACT FROM AUTHOR]

This paper presents a systematic investigation into modelling capacities of three conventional data-driven modelling techniques, namely, wavelet-based artificial neural network (WANN), support vector regression (SVR) and deep belief network (DBN) for multi-step ahead stream flow forecasting. To evaluate the effectiveness of these modelling techniques, hydro-meteorological hourly datasets from three case-study rivers located in the UK have been used. A heuristic performance analysis of the modelling schemes has been conducted by systematically analysing the key statistics that measure magnitude, scatter and density of model errors. Finally, for each of the modelling techniques, the performance deterioration rate in time was estimated. The results show that the SVR model can forecast quite accurately up to one to two hours ahead but its performance deteriorates gradually from three hours onwards. Further it has been found that the WANN model performs better when the overall non-linearity of the system increases, whereas the DBN model appeared to show consistently poor predictive capabilities when compared to the other models presented herein. The authors conclude by stating that, for any selected model, it is possible to use an identical model structure for up to two steps ahead forecasting. Models need to be re-configured beyond that limit. [ABSTRACT FROM AUTHOR]

Climate change modelling has improved significantly in recent years and the impact of climate change on flooding in the UK and internationally has become an area of increased importance. Flooding in the UK occurs for a range of reasons; this paper examines some of the predicted changes related to rainfall processes. The different types of rainfall in the UK can be categorised into groups such as frontal, orographic and convective, and combinations of these. Notable flooding events in the UK in recent years have been caused by different types of rainfall; Boscastle in 2004 and the widespread autumn 2000 floods being examples of quite different rainfall processes. Predicting how different types of flood-producing rainfall will change in the future climate presents researchers with major challenges, including that of spatial scale and uncertainty in the predictions. This paper highlights some of these challenges and looks at areas where future research could be focused. [ABSTRACT FROM AUTHOR]

This article is based on the flood events in Cornwall, UK, in November and December 2012, and takes forward the arguments presented in a paper entitled 'Building community resilience' published in November 2012. It uses a case study in Lostwithiel, Cornwall, to argue that if public agencies and local communities work and plan together, using all available data, then proactive steps can be taken to build resilience that assists in both the response and recovery stage of major incidents to minimise the direct impacts of floods and ensure that communities can return to normal as soon as possible after an event. This article also highlights some of the wider impacts that need to be considered when planning for emergencies [ABSTRACT FROM AUTHOR]

Water quality models are increasingly being routinely used to help ascertain the quality of water in drinking water distribution systems for design and operational management purposes. Conventional water quality models are demand driven and consequently do not incorporate the effects of any deficiency in pressure on the water quality throughout the distribution network. This paper assesses a new integrated pressure-dependent hydraulic and water quality model. The model is an extension of the well-known Epanet 2 model that has an embedded logistic pressure-dependent nodal flow function. Hydraulic and water quality analyses based on two water supply zones in the UK were conducted for a range of simulated operating conditions including normal and subnormal pressure and pipe closures. It is shown that operating conditions with subnormal pressures, if severe and protracted, can lead to spatial and temporal distributions of the water age and concentrations of chlorine and disinfection by-products that are significantly different from operating conditions in which the pressure is satisfactory. The results presented may be indicative of modelling errors that may not have been recognised explicitly hitherto. [ABSTRACT FROM AUTHOR]

A list of referees who have reviewed papers for Water Management between January 1, 2006 and December 31, 2006 is presented. These include W. Abu Judeh, B. Bockelmann-Evans, and B. Woods Ballard. Papers published in the "Proceedings of the Institution of Civil Engineers" must be submitted to at least two independent referees to judge accuracy, importance, and interest.

Operational needs commonly dictate the evolution of hydrometric networks. Such an approach can fail to meet long-term water management information objectives. This paper investigates how spatial descriptors can be used to assess the strategic value of individual catchments in the UK gauging station network. A catchment utility index (CUI) is presented based on an automated implementation of the Flood Estimation Handbook pooling-group procedure for assessing catchment similarity. The CUI is derived from the frequency with which gauged catchments across the UK are called in the pooling-groups for around four million catchments. Several case studies illustrate how the index is interpreted and used—in combination with the hydrometric performance of gauging stations and the degree of disturbance to the natural flow regime—to identify the most strategically useful gauged catchments. Such information is an essential component in guiding network evolution and in improving the effectiveness of procedures to estimate river flows in ungauged catchments. [ABSTRACT FROM AUTHOR]

The article discusses the flow resistance of wastewater pumping mains. According to the paper, if civil engineers will avoid to use the sewage lift-stations, it would be the obligation of the municipality to operate such station. It shows that Great Britain alone spends £150 million annually on lift-station electricity which is caused by the necessity to overcome the hydraulic resistance of the forcemain. Moreover , characteristic curves are presented.

This paper summarises a research investigation carried out on behalf of the Environment Agency. The investigation was concerned with the adaptation of flow measurement structures, designed in accordance with British or International Standards, to aid the upstream migration of fish. It was intended to ensure that these adaptations do not significantly degrade the accuracy of the combined structure as a hydrometric device. The research provided specifications for adaptations to benefit fish migration without significantly affecting hydrometric performance. This paper focuses on the key findings from the research. [ABSTRACT FROM AUTHOR]

The article presents a discussion between the authors and Peter Spencer of the British Environment Agency (EA) North West Region about modeling the hydraulics of the Carlisle 2005 flood event. One-dimensional (1D) and hybrid 1d/two-dimensional (2D) models were used in reviewing rating curves of key flow gauging stations in the Eden catchment after the 2005 floods. Details of the 2005 flood event are discussed.

In the UK, a disparity exists between modelled future weather/climatic patterns and the assessment of climate change impact on flood risk in the UK statutory planning process. Specifically, the impacts of climate change on the physical characteristics of a river catchment (e.g. land-use change, vegetation cover, soil moisture) are not considered when generating climate change weighted design flood events to assess the potential impact of flooding on a development in the future. Instead, a UK-wide averaged perturbation factor is applied. In this paper, a method is tested to integrate climate change data from UK climate projections 2009 (UKCP09) into design flood estimation methods (ReFH) as part of the current planning process. Scenarios are developed for a single, critical duration, 1% probability (1-in-100 year) design flood event that reflects plausible changes in catchment physical parameters in the 2080s. Initial results suggest that a 1-in-100 year storm in the 2080s may be greater in magnitude, rise and recede faster, and be associated with greater depths of flooding than predicted using current flood risk assessment frameworks in the UK. This information could provide new information to help developers choose more sustainable, flood-resistant and resilient designs. [ABSTRACT FROM AUTHOR]

Current and future water demand pressures arising from inadequate supplies and forecasts of increased population in the UK have prompted the government and other stakeholders to set up strategies that will ensure sustainable water supplies. Demand-side management strategies are one of the key priorities being pursued and the water regulator, Ofwat, has set a target of 13% reduction from 2010 levels of per capita household water consumption in England and Wales by 2030. This paper reports on estimated water wastage in UK households resulting from users waiting for water to reach a sufficiently warm temperature when using a hot water outlet (including kitchen sinks, showers and hand wash basins). It is estimated that, on average, 10% of the daily average per capita water consumption in UK households is wasted in this way. Possible means of reducing this waste are identified and a recommendation is made that boilers should carry a water efficiency rating in addition to the standard energy efficiency rating. [ABSTRACT FROM AUTHOR]

Infrastructure assets require suitable management and assessment protocols due to age-related deterioration, extreme weather events and climate change impacts. Above-ground river crossings are weak links in pipe networks since bank erosion and scour can undermine the integrity of built structures. A simple protocol was developed to assess river bank stability in the vicinity of river pipeline crossings. The erosion risk index (ERI) follows established bank erosion estimation techniques, adapted for users who are not trained geomorphologists. Calculation of the ERI is based on analysis of photographs acquired during an optimised inspection protocol using a custom app on a ruggedised tablet computer. The ERI was tested across Scotland and proved to be adequate for a first-order geomorphological assessment and to provide a classification of crossings according to susceptibility to river bank erosion. The ERI is transferable, with appropriate testing, to other infrastructure river crossing networks in the UK and beyond. The methodology used to develop and test the ERI is applicable to the development of other protocols to manage and assess infrastructure assets. [ABSTRACT FROM AUTHOR]

This paper describes the potential role of third-sector rivers trusts charities in co-delivery of the EU water framework directive. It uses as a case study the Tyne Rivers Trust in northeast England. The aim of the paper is to critically evaluate the capacity of the third sector to help deliver the vital public engagement, evidence-based strategies and practical measures required by the directive within a 'big society' political context. The trust has several avenues of work, which heavily depend on stakeholder participation, from education, through debates on problem issues concerning the river to active voluntary work on measures to relieve 'pressures' identified for local waterbodies under the directive. The trust also undertakes, in partnership with the Environment Agency, riparian works on aggravated sources of siltation -- an identified threat to the biodiversity of the River Tyne. The paper ends with an assessment of the successes and failures of the organisation in its stakeholder relationships: 'engagement' is identified as a vital element of the niche occupied by rivers trusts. It is seen as vital for the trust to maintain and adapt its successful 'localism' model during a period of rapidly growing influence on river management issues. [ABSTRACT FROM AUTHOR]

In urban areas, the impacts of flash floods can be very severe as these regions are generally densely populated and contain vital infrastructure. Parts of the UK have been particularly prone to serious urban flooding in recent years, such as Boscastle in 2004. Due to climate change, the occurrence of urban flooding is predicted to increase in the future, which is likely to lead to increasing flood risk to people and property in urban areas. It is therefore appropriate to estimate potential flood risk to people and property for improved flood risk management. This paper outlines an integrated numerical model for estimating flood risk in urban areas. The model includes a module for predicting the two-dimensional hydrodynamic characteristics of urban floods and a new module for predicting the flood risk to people (both children and adults) and property (including vehicles and buildings). The hydrodynamic module of this model was verified against laboratory experimental data and real flood tracks in urban areas. The integrated model was also applied to predict the flood risk to people and property for the Boscastle 2004 floods, with different recurrence frequencies. The developed integrated model can be used to predict the potential flood risk to people and property in urban areas and such predictions can be used as a rough assessment in improving flood risk management. [ABSTRACT FROM AUTHOR]

The use of precipitation estimates from weather radar for hydrological applications has been limited by the quantitative accuracy, reliability and resolution. The adoption of a more centralised approach to radar data processing, upgrades to telecommunications links and the installation of additional radars in the UK weather radar network have enabled some of these limitations to be addressed. The development of more flexible product generation software, which more fully exploits the resolution of the radar measured reflectivity, now provides for the mapping of precipitation on scales of 1 km and even below, thus approaching the resolution requirements for applications in urban hydrology. This paper describes the methods by which these high-resolution precipitation products are now generated. Illustrations of the products are given and their use in predicting flow using an urban drainage model is demonstrated. Issues affecting data quality, and the advantages and disadvantages of using radar products at high resolution are discussed. [ABSTRACT FROM AUTHOR]

The Cardiff Bay barrage, a 1.1 km long structure across the mouth of Cardiff Bay impounding a 200 ha freshwater lake, was central to the UK government's urban development programme to regenerate the docklands area of Cardiff. The Cardiff Bay Barrage Act 1993 included a groundwater protection scheme for buildings, providing owner/occupiers with recourse to remedial works or compensation should circumstances prove that construction of the barrage caused or probably caused groundwater damage. To allow a comparison of pre- and post-impoundment groundwater levels underlying south Cardiff, a groundwater monitoring system comprising 236 automated data loggers covering an urban area of 15km2 was established between 1995 and 1999. To mitigate the possibility of a rise in groundwater levels in certain identified areas, various types of groundwater control systems were installed prior to impoundment in November 1999. Management (including collection and interpretation of data) and maintenance of such an extensive system have required great effort, resourcefulness and logistics. This paper presents a brief history of the scheme and an overview of the management of such a diverse and challenging groundwater project. [ABSTRACT FROM AUTHOR]

Statistical, deterministic and heuristic approaches to modelling sewer performance and condition are briefly examined and a case-based reasoning (CBR) approach is proposed that can operate within the prevailing data environment of UK water utility companies. This is a technique that solves new problems by adapting previously successful solutions to similar problems. The use of CBR for other types of infrastructure assets is noted, and a method for its application to sewers is proposed. The methodology was tested on sewer data drawn from two water company regions. Validation trials, based on inferring known outcomes on 20 pipe lengths, show that a range of performance and management information and maintenance prioritisation can effectively be inferred from a case library of a small number of pipes for which good information is available. The paper concludes this is a pragmatic and flexible approach that utilises the industry's own experience and avoids the need for widespread calibration of more statistically or deterministically oriented models. [ABSTRACT FROM AUTHOR]

British Waterways is the largest navigation authority in the UK, managing a network of 3200km of inland waterway. Central to this function is the management of a large and complex water supply system: water is transferred across the network for resource management, to maintain navigation, for sale to third parties and for flood relief. Understanding the movement of water is essential to the effective and efficient management of this system. One-dimensional hydraulic models are routinely employed by water engineers to investigate such regimes throughout the UK. This paper describes recent studies aimed at reducing the uncertainties associated with the application of such models. This was achieved with a programme of primary research that included extensive site surveys, hydraulic trials and modelling. The outputs of this work include: validation of Manning's roughness representation for canals; determination of roughness coefficients for a range of bed and bank protection types; development of a practical relationship for determining the effective roughness of vegetated canals; and the quantification of the impact of canal constrictions. This work is of interest to consultants, researchers and those who undertake hydraulic modelling studies of canal systems. [ABSTRACT FROM AUTHOR]

Wrapt (Weather generator rainfall analysis processing tool) is a software tool created as part of a UK Water Industry Research project on the impact of climate change on sewer networks. It allows users to generate design storm change factors and select timeseries from output of the UKCP09 (UK climate projections 2009) weather generator without the need for manual processing or detailed knowledge of weather generators. Wrapt has been developed to assess changes in extremes of short-duration rainfall events - relevant to assessing the performance of sewer networks - but also has potential for applications elsewhere (e.g. water quality modelling). [ABSTRACT FROM AUTHOR]

Phosphorus enrichment in waterbodies can increase the risk of eutrophication and be detrimental to the health of dependent ecosystems. Phosphorus is a common reason for a waterbody failing to meet the Water Framework Directive 'good' status. The Watton Brook (Norfolk, UK) is required to meet good status by 2027; it currently has an overall 'moderate' status and a 'poor' status for phosphate (as of 2016 classification). Source apportionment modelling predicts treated effluent from water recycling centres is the primary phosphorus source to the Watton Brook, followed by significant agricultural contributions. Considering the agricultural sector input and the cost of upgrading sewage treatment, this study took a stakeholder- and ecosystem services-led approach to explore catchment-based solutions. The feasibility for an integrated catchment approach builds on detailed environmental conceptualisation, phosphorus source apportionment ground-truthing and a review of potential costs and benefits. By combining Farmscoper, SIMCAT-SAGIS InVEST modelling and an ecosystem services assessment, the study targeted solutions to reduce phosphorus loading while delivering multiple benefits. The feasibility and natural capital enhancement focus of a phosphorus balancing scheme in the Watton Brook ensures that the proposed solutions are cost-beneficial for both the wastewater company and its customers while offering wider benefits for the environment and the local community. [ABSTRACT FROM AUTHOR]

The article discusses the methods applied to measure channel roughness in Great Britain including the considerations taken while using the conveyance estimation system (CES). The established roughness advisor is unable to give a true picture of the roughness which occurs in alluvial streams as a result of variation in bedform configurations. The CES software does not take into account the changes in hydraulic roughness resulting from changes in alluvial bedforms.

The article shows the grid-to-grid (G2G) model applied by Flood Forecasting Centre in predicting floods that will occur in England and Wales. The approach has been applied on the British Environment Agency national flood forecasting system platform, where it produces flow predictions on a 1-square kilometer-grid and is driven by a rainfall time series per model grid cell. Results proved that it can be applied with existing flood forecasting solutions to produce accurate flood forecasts.

The article reveals the radar solutions used in flood forecasting in Great Britain. The use of radar in predicting floods started through the Dee Weather Rader Project in the 1970s, which created the real-time rainfall measurement system. Various radar solutions applied in British flood forecasting operations include dual-polarisation, radar-based quantitative precipitation estimates, and short-term ensemble prediction system.

The article evaluates data-based mechanistic (DBM) flood prediction models used in Great Britain. This approach was tested in River Lod and River Wallington catchments in southeastern portions of England, where it applied real-time, 15-minute information to foresee floods in those areas. Results showed that DBM perform better at longer lead-times, causing it to forecast floods slower than the conceptual rainfall-runoff models.

The article evaluates the developments in operational hydrometeorology in Great Britain. British Environment Agency hydrologists have been offering flood prediction services at the Flood Forecasting Centre of England and Wales including extreme rainfall alert service, flood guidance statements, and an online service for users. Probabilistic flood forecasting has been considered in predicting floods in the country, although it has yet to be proven in identifying actions done in case of floods.

In the context of flood management in urban areas in the UK, the Gaussian displacement spatial-temporal model (GDSTM) is used to generate a continuous rainfall field. The model makes the assumption that storms arrive according to a Poisson process in space and time, triggering another Poisson process of cell arrivals over the storm duration. These cells are displaced from the storm centre according to a normal distribution. Historic rainfall events are identified from a 3.5-year record of Met Office weather radar data from three different radars and the characteristics of the interior of each event are represented by 11 parameters. The process of event arrival is described by six additional parameters. For each month within the radar data record, a library of model parameters is obtained and used to develop simulations of 100 years of continuous, spatially varying rainfall at 5 min intervals and 1 km spatial resolution over three regions: London, Bradford and Glasgow. The objective is to use the synthetic data as input to existing urban drainage models to examine system performance. It is possible to reproduce standard statistics over the London region but the extreme values are underestimated when compared with statistics from the Flood Estimation Handbook (FEH). The mean rainfall is overestimated at the other sites but more agreement in simulating the extremes is observed when compared with the FEH. [ABSTRACT FROM AUTHOR]

Fluvial flows and tidal flows are governing on tidal rivers while fluvial flows are governing on non-tidal rivers alone. In addition to analytical and numerical models, stochastic methods must be considered to determine water surface elevation at the tidal limit of tidal rivers because hydraulic routing of this reach is very complex. In the present research, the neural network method was considered for determination of water surface elevation at the tidal limit of tidal rivers. The artificial neural network (ANN) method was trained using results from a suitable numerical model. The results of the ANN method were compared with results for the governing regression relation for water surface elevation at the tidal limit of tidal rivers. The ANN method was applied to the Karun river in Iran and the River Severn in the UK. The ANN method was found to produce water surface elevations for different combined return periods in the Karun river and the River Severn. [ABSTRACT FROM AUTHOR]

The pressure dependency of withdrawals from water distribution systems under conditions of abnormal stress, such as mains failure or fire fighting, is well accepted. A simple sequential solution seeking iterative approach to obtain a solution for pressure constrained outflows (including leakage) based on repetitive substitution into conventional computational algorithms, where demands are generally predetermined, has been developed. The methods are presently configured to use the computational efficiency and versatility of the widely used EPANET-2 software routine, offering the benefits of full network operational specifications at the level of 'commercial' network applications. Application of the new algorithm to UK water networks under various partial failure conditions has given insight into the 'true' extent and scale of supply deficiency as a consequence of pressure shortfall. The failures of one link of the network at a time have been simulated. The results suggest that, in terms of the nodes (properties) affected by shortfall in pressure, the more rigorous approach reduces the zone of deficient service compared with that flagged by conventional investigations. A case study used the methodology to investigate loss of resilience arising from pressure management and to assess the susceptibility to supply interruption of sensitive customers. [ABSTRACT FROM AUTHOR]

The ability to forecast the burst behaviour of pipes in water distribution systems is a fundamental requirement of proactive planning for investment, replacement and rehabilitation strategies. Burst behaviour is, however, a complex function of many uncertain contributing factors. Attempts to develop accurate predictive models have been limited by: data quality and quantity; the lack of associations between individual events and pipes; and the statistical techniques available and applied. Predictive expressions for annual burst rate in cast-iron and asbestos cement pipes are derived for two sample data sets from the UK. The available data were interrogated to make rigorous associations between individual events and pipes and filtered for missing, default and erroneous data. Using statistical analysis, the theory of generalised linear models, it was then possible to derive predictive expressions for burst probabilities. The resulting expressions show strong associations between annual burst rate, diameter and length and a complex association with age. Analysis was also undertaken to investigate associations with available soil data; a relative lack of consistent dependence of burst rate on these data is demonstrated. [ABSTRACT FROM AUTHOR]

Diffuse-source nutrient pollution remains a major problem within sustainable catchment management. The aim of this study is to provide a decision-support tool that can predict the impact of land-use changes on water quality (WQ) in receiving waters. A linked modelling approach was used to integrate land-use changes with a WQ model and a 2D numerical hydrodynamic model. The linked model was adapted to conditions in estuarine and coastal waters and applied to the catchments of Carmarthen Bay in West Wales, UK. A new set of biochemical reaction rates for nutrients in estuarine waters was found and presented. This approach took into account the assessment of nutrient production rates in the catchment for dry and wet weather conditions, as well as the reactions of constituents passing from the catchment into the coastal basin. The predominant types of land use in the catchment are arable land, improved grassland, rough grazing and woodland. Nutrient loads from these areas were estimated using Geographical Information System (GIS) data and export coefficients, which characterise the amount of nutrient losses. Furthermore, economical and ecological effects of land-use changes were integrated using an input-output analysis approach. A range of scenario simulations involving different river discharges and reduced nutrient input rates resulting from appropriate measures for land-use changes showed the nutrient pathways and concentration distributions over time throughout the bay. The outcome from these scenario simulations can be used to indicate catchment-wide distribution of diffuse pollution sources and to locate areas that are characterised by high nutrient concentrations and are prone to the occurrence of mass algal growth. [ABSTRACT FROM AUTHOR]

Nine sediment transport formulae were reviewed and applied to both inbank and overbank flows in straight and meandering compound channels. The predictive capabilities of the formulae were evaluated using experimental data obtained from the large-scale UK Flood Channel Facility and the small-scale Ulster Channel. The Yang formula (1979) was found to give the best prediction for sediment discharge, performing well for both straight and meandering channels. The Schoklitch (1962) and Yang and Lim (2003) formulae also gave very good predictions for most of the data sets studied. The Ackers and White formula (1973) gave very good prediction for the large-scale facility but overpredicted the sediment discharge for the small-scale channel. The Karim and Kennedy (1981) formula could also be a good sediment discharge predictor, for the studied flow conditions, but the coefficient of proportionality used in the formula needs to be calibrated. [ABSTRACT FROM AUTHOR]

The Foresight Future Flooding project has analysed future flood risk in a scenario framework for the whole of the UK. The analysis predicts increasing flood risk unless current flood management policies and investment levels are changed, with up to a twentyfold increase in economic risk by the 2080s. The increase is attributable to a combination of climate change and increasing value of household, industrial and infrastructure assets. Potential responses are assessed in terms of the three pillars of sustainability: social, environmental and economic. The work described has formed much of the evidence base for the new government strategy for flood risk management in England, 'Making space for water'. [ABSTRACT FROM AUTHOR]

The article presents information on the physico-chemical water treatment system for relief agencies. A physicochemical water treatment system was developed which has a minimum of power and mechanical plant requirements. The system comprised a pump driving the raw water supply through a spiral pipe flocculator and an upflow clarifier of novel new design fabricated within a standard Oxfam TII tank. This system was intensively tested and developed in Great Britain in a joint Department for International Development and Oxfam-funded research and development project.