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The article presents a list of paper related to water management that were given honors in 2005. The paper on Pehur high-level canal by A. Laycock and colleague was given the Overseas Prize awards. The paper on real-time hydro-power forecasting on the Victoria Nile by R. B. Wardlaw and colleague was given the Robert Alfred Carr Prize award. The article on the impact of climate change on Great Britain's flooding and future predictions by M. Dale was presented with the Telford Premium award.

El Niño/southern oscillation (ENSO) activity is known to affect weather patterns in many parts of the world. This paper develops an approach to identifying signals and incorporating associated impacts on hydrological risk into water resources planning and management. The paper builds on earlier research reported in the climatology literature, and brings this to the engineering domain. An evaluation of seasonal rainfall in Guyana clearly demonstrates that distinct rainfall distributions are associated with La Niña and El Niño events. Forecasts of these events are made by a number of organisations at lead times of up to eight months. If these are coupled with the precipitation analysis presented in this paper, an objective hydrological risk assessment can be made. The methodology applied in Guyana has been repeated with data on net basin supply to Lake Victoria. There is a clear indication of a link between ENSO activity and net basin supply to Lake Victoria. [ABSTRACT FROM AUTHOR]

Climate change is affecting flow volumes and regimes in glacier- and snow-melt-fed catchments. Together with increasing demands for water, this is putting many water users under increasing water security risk. The mines of the high Andes are one user group experiencing increased water stress. This paper illustrates the climate change problem using a 40 year hydro-climate data set from the headwaters of the Aconcagua basin in central Chile and describes the integration of climate, hydrology, mine water system and financial risk models to evaluate potential water supply solutions. It is concluded that existing water supplies are not sufficiently secure under baseline conditions and less secure under future climate scenarios. Recirculating water from the tailings storage facility, despite the large capital and operations costs involved, is considered the optimal climate-resilient solution and also offers social and environmental advantages. However, considerable modelling uncertainties exist, primarily related to spatial precipitation. [ABSTRACT FROM AUTHOR]

Urban water managers need to adopt water demand management (WDM) as one of the ways to provide for the needs and demands of escalating urban populations, amidst the negative impacts of increased pollution loads and climate change on finite water resources. This paper reviews how urban water tariff structures could be designed to promote water conservation in households while also ensuring revenue sufficiency for the service providers and affordability for low-income households. As an example, the paper describes the case of Zaragoza (Spain), a city where implementation of a water-conserving tariff and providing economic incentives largely contributed to a 27% reduction in overall water consumption between 1996 and 2008, although the population of the city increased by 12%. Similar principles were adapted to model a water-saving, socially equitable tariff for the city of Kampala (Uganda). The proposed tariff for Kampala can save over 2·5 million m of water and generate an extra US$ 0·68 million of revenue per year, which could be used to extend water services to currently unserved households in low-income settlements. If implemented, the tariff could enhance economic efficiency, revenue sufficiency, social equity and service coverage. [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]

Urbanisation and climate change have increased both the probability and the severity of flooding. The risk paradigm that follows shifts from traditional to more integrated approaches, since one of the main tasks emerging for flood managers is the development of resilient cities. The concept of urban resilience is becoming more and more important, despite the numerous challenges that interfere with its implementation. The goal of this research is to study how engineering and other design disciplines can improve flood resilience on an urban neighbourhood scale. This paper presents the analysis of an overview of research aimed at operationalising urban resilience to floods. This literature highlights the fact that almost no references can be found concerning studies focused on operationalising flood resilience at the neighbourhood level and particularly through urban design practices. Indeed, through interviews conducted with several stakeholders, it was confirmed that clear cooperation between flood resilience and urban design practices at the neighbourhood level does not yet exist. [ABSTRACT FROM AUTHOR]

The article reflects on the flood risks management in the Great Britain and the factors that causes these risks. It states that these flood risks are proofs of climatic changes. It also mentioned the damages cause by floods which includes losses in life and properties. It also presents the issues tackled in the journal.

The planning of future supplies of agricultural water is beset by uncertainties stemming from inaccuracies in general circulation models, assumed greenhouse gases emissions scenarios (GHGESs), imperfect models employed for estimating reservoir inflows and approximate methods for estimating agricultural water demand. The uncertainty of providing agricultural water under climate change was assessed, relying on simulations involving baseline (1971–2000) and future periods (2040–2069 and 2070–2099). Climatic variables were simulated using six atmosphere–ocean general circulation models (AOGCMs) driven by GHGESs A2 and B2 in the Aidoghmoush basin, Iran. Projection of reservoir inflow was performed using the IHACRES model and artificial neural network (ANNs). Agricultural water demand was calculated using the FAO–Penman–Monteith and Hargreaves-Samani (HS) methods. Eight modelling scenarios were considered based on combinations of AOGCMs, GHGESs, reservoir inflow and agricultural water demand projections. Reservoir operation rules were calculated with a particle swarm optimisation algorithm. The results show that agricultural water demand will increase in future periods compared with the baseline period. The operation rule derived from the combination of the HS and ANN models (under GHGES A2) showed the best performance in 2040–2069 by achieving the highest reliability (93%) of water supply. The operation rule derived from the combination of HS and ANN models (under GHGES B2) achieved the highest reliability (95%) of water supply in 2070–2099. The results provide adjusted reservoir operation rules under uncertainty caused by climate change and related impacts on water resources management. [ABSTRACT FROM AUTHOR]

The occurrence of scour around bridge elements due to the transportation of bed material during flood events can cause serious structural damage and loss of life. Increased uncertainties in precipitation and runoff predictions due to climate change make this phenomenon more complex and dangerous. Bridge scour countermeasures should thus be more focused on decreasing scour formation around bridge elements. In this study, abutment scour under clear-water conditions with constant flow intensity was conducted and collars were tested as scour countermeasures around semi-circular end bridge abutments. The experimental study was performed in a rectangular channel with an almost uniform cohesionless bed material for 3 h with and without collars. Collars of various lengths located at different elevations around the abutments were tested to investigate the effect of collars on scour development. The results of the study showed that the scour depth decreased with increasing collar width and when the collar was placed below the bed level for a given abutment length. The results were compared with those of similar earlier studies to show the effect of abutment shape, size of the bed sediment and test durations on the development of scour depth around abutments. [ABSTRACT FROM AUTHOR]

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]

An introduction is presented in which the editor discusses various reports within the issue on reservoir management topics including reservoir operating policies in Thailand's Ubonrata dam, optimisation of hydroelectricity performance, and the effects of climatic changes on thermal stratification.

The hydrology of scarce-data areas, such as the mountainous area of the Andes, is poorly known mainly owing to the lack of data. Global gridded climatological datasets (GGCDs) are becoming more precise and common, but the utility of these datasets and their applicability to complex hydrological systems are still not yet well determined. In this paper the reliability of a GGCD is evaluated as an alternative source to supply the lacking in situ observations, with the aim of studying the hydrology of a mountainous area in south-central Chile. The GGCDs are found to recover the climate variability in Andean areas, and partially recover the orographic effect caused by the mountains. A finding of practical relevance is that GGCDs could be considered as an adequate source for performing hydrological models and studies under high spatial variability and scarce-data environments such as the Andes. [ABSTRACT FROM AUTHOR]

The Trust project, funded by the European Commission's Life+ programme and the Italian Ministry of Environment, aims to identify adaptation and mitigation measures to counteract the impacts of climate change on the groundwater of the upper plain in the Veneto and Friuli regions in northeastern Italy. Intensive groundwater abstraction over recent decades has resulted in declining water table levels; this problem, common to many other places in the world, will be exacerbated by future temperature increases unless appropriate solutions are adopted. Trust aims to implement a water balance modelling tool to support institutions in formulating sustainable water management planning policies and best practices. This paper reviews the development and application of the water balance model that simulates water deficit affecting summer crops using agronomic and climatic data at small spatial and temporal resolution. Remote sensing identification methods were employed to map irrigated crops. Projections on the water deficit as a function of climate change have used future precipitation and evapotranspiration patterns derived from climate simulations (SRES-IPCC scenarios A1B and A2) of the Mediterranean region for the twentieth and twenty-first centuries. Model outputs showed that, due to climate change, water deficits for summer crops could be of the order of 400 mm, while the balance model showed that climate change can lead to a reduction of average groundwater resource of about 5-10%, especially in the apical areas of the high plain. However, a significant part of the future water deficit might be recovered through rationalisation of water withdrawal and managed aquifer recharge areas. [ABSTRACT FROM AUTHOR]

This paper addresses the impacts of climate change on hydrology and water resources in the Karkheh River Basin (KRB), which is the third most productive basin in Iran and has great potential for hydropower generation. The total potential capacity of reservoirs in this basin is more than 15 ×10 Mm, of which 40% has been built. The sensitivity of the KRB to potential climate change is investigated by simulating basin streamflow response under different climate change scenarios. A conceptual rainfall-runoff model (IHACRES) was first calibrated by using hydrological and streamflow observations. The model was then applied by downscaling two general circulation model outputs (CGCM3 and HadCM3) under three emissions scenarios (A1B, A2 and B1). The results show that, in the short term, annual mean temperature increases by about 0·9°C, the annual amount of precipitation will not change significantly and annual streamflow decreases by 10-15%. In the mid and long term, respectively, temperature increases by more than 2·0°C and 4·0°C, precipitation decreases by about 15 and 17%, and annual streamflow decreases by about 25 and 32%. [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]

Water resources/reservoir management in developing countries attracts considerable attention due to growing human requirements and environmental concerns. The Seimare–Karkheh hydropower reservoir cascade, in the Karkheh River basin southwest of Iran, was studied. The impacts of changing reservoir operating water levels on hydropower generation and downstream environmental requirements were evaluated under different climate change conditions. For several years, the operating water level of Seimare reservoir was 704.5–720.0 metres above sea level (masl) (H1). Decision makers then adopted a different policy, with the operating range changed to 704.5–723.0 masl (H2). More recently, decision makers reduced the normal and minimum water levels so the reservoir now operates at 695.0–704.5 masl (H3). It was found that, for the period 2006–2050, based on H3, hydropower production would be reduced by 2.3–12.1% and 2.4–12.6% compared with policies H1 and H2, respectively. In 2051–2100, these reductions were found to be 5.8–11.2% and 7.7–11.3%, respectively. Furthermore, the results demonstrated that the current policy would substantially affect downstream hydrological alteration: 60–72% in Seimare River and 48–66% in Karkheh River for the period 2006–2050. The issue was found to be more pronounced in 2051–2100, with hydrological alteration of 68–73% in Seimare River and 59–66% in Karkheh River. [ABSTRACT FROM AUTHOR]

It is necessary to perform analysis to confirm stationarity or detect non-stationarity of extreme rainfall data in order to derive accurate design rainfall estimates for hydraulic structure design. In this study, non-stationarity of extreme rainfalls in the Antalya region in Turkey was investigated through statistical non-stationarity tests and stationary and non-stationary generalised extreme value distribution models. After determination of stationarity of extreme rainfalls in the Antalya region, a frequency analysis was conducted in a stationary context to derive design rainfall intensities. Future (2080-2099) design rainfall intensities were then estimated and bias corrected, and current and future design rainfall intensities were compared and discussed. Non-stationarity analysis showed no evidence of non-stationarity in Antalya. Bias-corrected future design rainfall intensity estimates showed that design rainfall intensities in the future are expected to be larger than current design rainfall intensities for return periods of 5, 10, 20, 50 and 100 years. This study is expected to contribute to a better understanding of the relationship between global warming and extreme rainfall in one of the most climate change sensitive parts of Turkey. [ABSTRACT FROM AUTHOR]

The impacts of climate change on the conjunctive use of surface water and groundwater resources of the Khorramabad basin were evaluated. Monthly temperature and rainfall modelled using HadCM3 and CGCM2 under greenhouse gas emissions scenarios (GHGESs) A2 and B2 were downscaled to baseline (1971–2000) and future periods (2040–2069 and 2070–2099). Simulations were performed for four climate change scenarios (CCSs) (A2-2040–2069, A2-2070–2099, B2-2040–2069 and B2-2070–2099). The projections indicated an increase in temperature and a decrease in rainfall. Future surface water resources were simulated using IHACRES. The results indicated that average annual runoff under GHGESs A2 and B2 would decrease by, respectively, 2.03% and 4.17% in 2040–2069 and by 6.64% and 8.94% in 2070–2099. Groundwater simulation was carried out using ModFlow. The results showed that under, the four CCSs, groundwater level would decline by 2.3, 3.0, 2.5 and 3.4%, respectively, relative to the baseline. Aquifer recharge under the four scenarios would decline by 1.43, 5.71, 2.86 and 7.14%, respectively. The results from IHACRES and ModFlow were employed to develop a conjunctive operation model with the Weap model. Several CCSs with various levels of future water demand were assessed using Weap. A 20% increase in water demand relative to the baseline, for instance, was projected to produce annual deficits in future agricultural water supply of 3.3, 5.08, 3.05 and 5.18 (× 106 m3), respectively, under the four CCSs. [ABSTRACT FROM AUTHOR]

Data availability for in situ spatial variability assessment of hydraulic parameters is always limited in the vadose zone. In this work, laboratory and in situ experimental methods of parameter estimation were compared to investigate the best estimation method for heterogeneous soil. The Marquardt–Levenberg and non-linear least-squares optimisation algorithms were used for parameter estimation. The simulation error was minimised by selecting sensitive parameters during the numerical solution. The shape factor n was found to be the most sensitive parameter, followed by water content θs, saturated hydraulic conductivity (SHC) and the inverse of the air entry α. Compared with the in situ cumulative infiltration and simultaneous methods, the outflow method resulted in the best fit by minimising the error. During the comparison of outflow and cumulative infiltration methods, only θs showed a significant difference (p = 0.00). On the other hand, SHC showed a non-significant difference (p = 0.439) when the outflow and simultaneous methods were compared. During model predictions, the SHC measured by the simultaneous method showed reasonable estimates for surface horizon and weak correlations (0.79 and 0.77) with deep soil water content, which could be improved by adding more hydraulic parameters. The cumulative infiltration numerical solution resulted in the most reliable estimates of hydraulic parameters for in situ heterogeneous soil. [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]

Two approaches are presented for using the UKCP09 weather generator (WG) to assess changes in extreme short-duration rainfall. The first provides change factors for design storms of varying duration and frequency, building on established hydrological techniques and with uncertainty estimation. The second approach characterises and facilitates the selection of WG timeseries for use in impact models. The methods have been tested at ten case study sites around the UK. The results show an increase in the intensity of short-duration (1 h and 12 h) events in winter but a reduction in summer, although the latter is subject to high levels of uncertainty. The number of intense events increases slightly and more significantly for some locations, especially in winter. Generally, it is hard to establish any conclusions geographically, although increases in rainfall intensity and events in the Lake District site stand out. The methods provide practical techniques for utilising the UKCP09 WG to assess the impacts of climate change, in particular for urban drainage and sewer modelling. [ABSTRACT FROM AUTHOR]

Thermal stratification is strongly associated with hydrodynamics, and plays an important role in the dynamics of water quality and the ecosystem of stratified water bodies. Changes in the climate or hydrological conditions can alter thermal regimes. This study aims to investigate the effects of climate change on the thermal structure of a reservoir. To quantify these effects, a hydrodynamic and water quality model was applied to the Latian dam reservoir in Iran. The outputs of the Canadian global climate model version 3 for B, AB and A scenarios were used to obtain future (year 2100) air temperature trends. Results from these scenarios were compared with those of base conditions to investigate the effects of climate change. The maximum surface water temperature increase was about 2°C for the S2 scenario, which was the scenario with the highest air temperature increase (5·7°C). The increase in water temperature indicated some important effects on thermal stratification; for example, thermal gradient across the metalimnion was increased. It was also inferred that the Latian dam was severely sensitive to inflow variations as well as temperature changes. [ABSTRACT FROM AUTHOR]

An extended method is presented for 'perturbing' design flood flows to account for climate change. Specifically, the method uses climate model output to directly alter parameters in the UK Flood Estimation Handbook rainfall-runoff model. The method is explored using a model of the River Eden catchment in northwest England, which comprises 26 sub-catchment hydrological models, with outflows routed using a hydraulic model. The results show a significant increase in flood flows and water levels by the 2080s, although uncertainties are large. The size of the increases varies depending on the climate change scenario and timing of the event, with the monthly precipitation change factor the single largest determinant of the change in peak flow. The method is reasonably simple to apply and there are benefits of using climate model information, rather than a sensitivity allowance, in terms of geographical interpretation of changes in precipitation and explicit representation of some of the uncertainty related to climate change. However, there are significant limitations to the methodology, in particular the minimal representation of antecedent conditions and more generally due to the ability of climate models to accurately reproduce and simulate extreme precipitation. [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]