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JRBM vol 5 Issue 1

The GLOWA Volta Project: Interdisciplinary analysis of the impact of global change on a river basin in West Africa
By NICK VAN DE GIESEN, CHARLES RODGERS and PAUL VLEK
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This article gives an overview of the structure of the interdisciplinary GLOWA Volta Project and its main scientific outputs. The article serves to provide the context for a set of articles written by project scientists for this special issue of the Journal of River Basin Management. After a brief introduction, a description is given of the Volta Basin in West Africa. The main issues related to changes in water supply and demand are presented. Climate change and variability, landuse change, and increasing competition for water between sectors are especially relevant. The integrative approach followed within the GLOWA Volta Project is given in detail. The choice was made to focus on conceptual integration early on, rather than at the end of the project. This led to a network structure for communication between disciplinary research modules. Finally, a listing of the individual articles in the special section is given, together with overall conclusions.
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Influence of soil-moisture and land use change on precipitation in the Volta Basin of West Africa
By HARALD KUNSTMANN and GERLINDE JUNG
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An ongoing intensification of agriculture in West Africa has lead to changes in surface and subsurface characteristics that may directly affect evaporation rates and, in turn, regional rainfall patterns. To investigate the effects of those changes, the Penn State University/National Center for Atmospheric Research (NCAR) mesoscale meteorological model (MM5) was applied for the identification of feedback mechanisms between land surface (soil and vegetation) and atmosphere. MM5 was applied in three different resolutions (81 x 81, 27 x 27, and 9 x 9 km2) with 2-way interactive grids. The objective of this work was to learn to what extent regional (intra-domain) evaporation determines rainfall within the domains. The effect of decreased and increased initial soil moisture on total rainfall and on precipitation recycling indicators was investigated. Scale dependent, positive (increased precipitation at increased initial soil moisture) as well as negative (decreased precipitation at increased initial soil moisture) feedback mechanisms were found. Detailed atmospheric water budget analysis showed that negative feedback mechanisms on the small domain appeared to have been caused by an increased inflow of atmospherc moisture. Sensitivity of precipitation with respect to soil moisture was very variable over space. Both negative and positive sensitivities were observed. To investigate the effect of land use change, the total rainfall distribution was computed under the assumption of the observed land use substitution from cropland woodland mosaic into shrub land and finally into grassland. Sensitivity of precipitation with respect to land use change was very heterogeneous. Total precipitation change was of the same order of magnitude as in case of the initial soil moisture perturbations.
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Climate trends of temperature, precipitation and river discharge in the Volta Basin of West Africa
By REBEKKA NEUMANN, GERLINDE JUNG, PATRICK LAUX and HARALD KUNSTMANN
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The impact of climate change on precipitation and water availability is of major concern for policy makers in the Volta Basin of West Africa, whose economy mainly depends on rainfed agriculture and hydropower generation. It is therefore essential to know if, and to which extent climate trends in the Volta Basin exist that impact water availability. In this study, the present trends in precipitation, temperature, and river discharge for the Volta Basin were analysed. Linear trend and corresponding levels of significance were calculated for time series of annual and monthly maxima and corresponding means respectively. Trends of total annual precipitation and standard deviations for all considered variables were analysed. In addition, the stability of linear trends was considered via reverse arrangement test. Clear positive trends with high levels of significance were found for temperature time series. Precipitation time series showed both positive and negative trends, whereas most significant trends were negative. However, due to the small number of significant cases, only weak trends towards a decrease in precipitation can be concluded. Most of the significant trends of the standard deviation in precipitation were negative. Due to this observation a trend towards a decrease in the variability of precipitation is concluded. In case of discharge time series, a small amount of (predominantly positive) significant trends for the wet season was observed. The majority of the significant trends for the dry season were negative. For discharge no clear trend could be evaluated though, as the anthropogenic influences (e.g. building of dams, intensified irrigation) could not be quantified. Both, standard deviation of temperature and of river discharge show positive and negative significant trends. Thus one can not draw the conclusion of a change in temperature and river discharge variability. It is additionally shown that monthly precipitation trends can be weakly linked to climate indices. This was achieved by linear correlation analysis between monthly precipitation amounts and the climate indices NAO, SOI, TNA, TSA.
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Demand and supply of improved water in the Ghanaian Volta Basin
By STEFANIE ENGEL, MARIA ISKANDARANI and MARIA DEL PILAR USECHE
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Growing efforts are undertaken at the local, national, and international level to improve water supply in developing countries and thereby help people to satisfy their basic water needs. This study aims at an evaluation of households' actual access to and use of improved water sources in rural communities in the Ghanaian Volta basin. A statistical analysis of a household survey conducted in the Volta Basin helps to demonstrate that access to improved water does not automatically translate into use of it for all households. Our analysis shows that 43 per cent of those households that had access to an improved source still use unsafe water as their main domestic water source. Relative distance to improved and unimproved sources, the pricing system established locally, and quality perceptions all are likely to influence household water source choices.
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Water and electricity sector reforms in Ghana: Back on track?
By SUSANNAWOLF, VERONIKA FUEST and FELIX ASANTE
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The lack of continuous and reliable supply of energy and water is a major hindrance to industrial and agricultural productivity in Ghana. Similar to the public utility management problems found in most developing countries, the electrical and water utility companies of Ghana have suffered from a number of institutional and operational shortcomings, including low collection rates, high wastage, operational losses, and inadequate staffs. Reforms of the energy and water sectors have been under way since the beginning of the nineties. Prices have increased significantly, but there has been little or no improvement in services. This analysis will focus on on-going reforms, their likely effects on different user groups and the obstacles for their implementation. Those who provided water and electricity were plagued with institutional weaknesses, and regulating agencies did not perform according to their mandates. The regulating agencies were lacking financial and human resources for monitoring, and their functioning suffered from principal agent problems. The government policy of private sector participation in utility provision has been only partially implemented for various reasons: the providers of water and electricity and the government agents that manage the reform process have a greater effect on manufacturers than they do on agriculture because the former have the greater need for regular supplies of water and electricity. The potentials and interest of the clients, regulating agencies and providers as well as the relationships between them have to become a key issue in the reform process. There is a need for more transparency and accountability on the part of politicians and providing agencies - whether public or private, local or national.
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Hydrological parameterization through remote sensing in Volta Basin, West Africa
By MOHSIN HAFEEZ, MARC ANDREINI, JENS LIEBE, JAN FRIESEN, ANDREAS MARX and NICK VAN DE GIESEN
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Ground-based hydrological data collection tends to be difficult and costly, especially in developing countries such as Ghana and Burkina Faso where the infrastructure for scientific monitoring is limited. Remote sensing has the potential to fill the gaps in observation networks. The GLOWA Volta Project (GVP) seeks to maximize the information to be gained from satellite imagery by combining remotely sensed data with strategically chosen ground observations. However, there is very limited information about the coupling of remotely sensed data with ground based data over the mixed savanna terrain of West Africa. This paper provides an overview of innovative techniques to measure hydrological parameters as actual evapotranspiration, rainfall, and surface runoff over mixed savanna terrain in a semi-arid region in West Africa, and their potential use. Evapotranspiration - The Surface Energy Balance Algorithm for Land (SEBAL) was used to calculate sensible heat flux and evapotranspiration through the energy balance. The SEBAL parameterization is an iterative and feedback-based numerical procedure that deduces the radiation, heat and evaporation fluxes. Along a 1,000 km gradient in the Volta Basin, three scintillometers were installed to measure sensible heat flux over distances comparable to NOAA-AVHRR pixels, approximately two kilometers. The comparison of sensible heat flux measured from remotely sensed data and scintillometers provide accurate results. This will help to increase the reliability of SEBAL parameterization. Rainfall - Depending on the region within the Volta Basin, up to 90% of the precipitation in originates from squall-lines. The Tropical Rainfall Measuring Mission (TRMM) imagery provides a valuable tool to monitor such squall lines. However, the TRMM signal should be validated for squall line rainfall. To increase the reliability of space-based rainfall measurements, TRMM based rainfall rate estimates were calibrated with rainfall measurements from a dense network of rain gauges. Surface Runoff - Remote sensing has limited value in estimating surface runoff. The savanna of West Africa, however, is dotted with a large number of small reservoirs used to supply water for households, cattle, and small scale irrigation. Bathymetry of sixty reservoirs in Ghana's Upper-East Region produced a very regular correlation between surface area, as observable by satellites, and volumes. By using all-weather RADAR imagery and the measured surface/volume curves, surface runoff volumes can be monitored throughout the year. These indirect runoff measurements will help researchers to develop surface-runoff models for the Volta Basin.
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A hybrid metric-conceptual (HMC) model for monthly riverflow prediction in the semi-arid Volta Basin of West Africa
By B.A. AMISIGO and NICK VAN DE GIESEN
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Data-based mechanistic modelling techniques have been applied to catchment monthly runoff, potential evaporation and rainfall time series to model monthly catchment runoff at selected gauging sites in the Volta Basin of West Africa. The aim of the study was to obtain a modelling framework that not only accounts for the rainfall-runoff non-linearity in the basin and provides acceptable predictions of the monthly catchment runoff for the sub-basins studied, but also reveals the necessary insights for a plausible interpretation of the rainfall-runoff mechanism in the basin. The rainfall-runoff process was considered in two stages - a nonlinear transformation from rainfall to effective rainfall and then a linear transformation from effective rainfall to runoff. First a linear time varying, state dependent parameter (LTV-SDP) transfer function model was applied to the monthly rainfall-runoff calibration series of each sub-basin to determine the form of the rainfall-effective rainfall non-linear transformation. The observed series (runoff or rainfall) that was significantly related to effective rainfall was then identified. Next, the functional form of this relationship was established and used to fit linear time invariant (LTI) transfer function models relating monthly runoff to monthly effective rainfall and potential evaporation. The best estimate of the monthly effective rainfall from the nonlinear modelling was obtained from the product of monthly rainfall and a fractional power of monthly runoff - the runoff acting as surrogate for catchment wetness. Since this form of effective rainfall cannot be used for simulation in validation mode (as the runoff series is unknown then), a non-linear rainfall filter used in the Identification of unit Hydrographs And Component flows from Rainfall, Evaporation and Streamflow data (IHACRES) application was used to model effective rainfall in this mode. The study showed that monthly catchment runoff in the basin can be decomposed into two parallel flows, an instantaneous (within a month) and a slower (with one month delay) flow components. These results suggest that baseflow contribution to streamflow is insignificant in the Volta Basin.
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JRBM vol 5 Issue 2

Probability of flooding upstream from a bridge as a function of its construction
By Marek Sowinski
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The main objective of this paper is to compare the probability of flooding areas upstream from a bridge without piers (with a deck supported only by abutments), with a bridge of the same width with piers (which deck is supported additionally by piers). However, the problem was treated broadly and an analysis contained an influential investigation of different factors affecting probability of flooding not only piers width and shape. The paper starts with the formulation of performance function used in reliability analysis. Then, after the short characteristics of the methods of this analysis, one of them – the advanced first-order second-moments (AFOSM) method chosen for solution to the problem is briefly described. The second part of the paper contains a case study of a bridge designed in town Srem on Warta River (Poland). Two models used for computation of hydraulic losses, which are required for determination of the performance function, are described. The first one is based on the energy equation (solved by the standard step method) and used for a bridge supported only by abutments, the second one applied for computation of losses in the inner section of a bridge supported by piers is based on the momentum equation. Computer simulations performed for the considered variants of bridge projects were used for comparison. The computations results were presented in the form of the exceedance probability curves (EPC) of the water level upstream from a bridge. It was found that application of piers to the construction of a bridge can significantly increase the probability of flooding, depending on the constriction effect of the piers. The performed analysis allowed to quantify the influence of factors deciding on this effect.
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Stakeholder participation in modelling for integrated catchment assessment and management: An Australian case study
By L.T.H. NEWHAM, A.J. JAKEMAN and R.A. LETCHER
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This paper addresses issues of participation in the development of integrated assessment and modelling approaches in catchment management, drawing on lessons from an Australian case study in the management of diffuse source pollutants in the Ben Chifley Dam catchment of south-eastern Australia. In discussing the nature and outcomes of the interactions with catchment managers and the catchment community, particular emphasis is given to activities associated with the development of a scenario-based modelling tool that enables users to evaluate the biophysical and economic trade-offs associated with a range of potential management changes. The case study demonstrates the extent to which the development of models and software can provide a focus for communication between researchers, catchment managers and the catchment community. Benefits of the participatory activities included: (i) ensuring that the research addressed the primary concerns of catchment stakeholders, (ii) improving the flow of information between researchers and catchment stakeholders, and (iii) fostering cross-agency collaboration. However, there were substantial resources required for participatory activities; these were initially underestimated. Features of the participatory processes which contributed to their success included: (i) early identification of the need for participatory activities and their continuation over the course of the case study (ii) incorporating a broad range of catchment stakeholders in participatory activities, (iii) tailoring participatory activities to specific groups of catchment stakeholders, and (iv) gaining the higher level support of local management organisations. Improvements to the process which were identified included reducing the reliance on a single management organisation and establishing an ‘exit strategy’ in the initial planning of the case study.
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Assessment of flood risk accounting for river system behaviour
By M.C.L.M. VAN MIERLO, A.C.W.M. VROUWENVELDER, E.O.F. CALLE, J.K. VRIJLING, S.N. JONKMAN, K.M. DE BRUIJN, A.H. WEERTS.
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In this paper “river system behaviour” is defined as the complex interaction between river flow and the flooding of flood prone areas. A basic aspect of river system behaviour is that a local dike breach may affect hydraulic loads and hence dike failure probabilities at other locations. Important aspects in river system behaviour are discussed as well as the fact that effects of river system behaviour on flood risk may be both beneficial as well as adverse. This paper presents a conceptual approach to quantify effects of river system behaviour on probabilities of dike breach and flood risk. It was successfully applied to two example river configurations. The results of these examples are discussed. It is concluded that for proper flood risk assessment all relevant failure mechanisms, uncertainties as well as all proposed safety improvement measures are to be jointly taken into account. The conceptual approach enable all this. In the authors’ views, there is a need for developing models that account for effects of river system behaviour on flood risk. Such models can serve as a tool for policy makers in evaluating the effects that (regional) safety improvement measures have on the flood risk in the entire river basin.
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Development of a non-intrusive and efficient flow monitoring technique: The space-time image velocimetry (STIV)
By ICHIRO FUJITA, HIDEKI WATANABE, RYOTA TSUBAKI.
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A novel image analysis technique for measuring river surface flow is proposed. When we assume that the brightness distribution of river surface image is convected with the surface velocity, a space-time image for a searching line set parallel to the main flow would indicate velocity information as its image orientation. The new technique, the space-time image velocimetry (STIV), is capable to measure the orientation angle of the pattern using the eigenvalue analysis of the local space-time image. The performance of STIV is compared with the other image analysis technique, the large-scale particle image velocimetry (LSPIV), previously proposed by the authors and it is shown that STIV is an alternative image analysis method for measuring streamwise velocity distributions efficiently.
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The Ythan Project: A case study of public participation in river restoration
By C.T. MORRIS
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TheYthan Project (2001–2005) was a catchment-scale partnership project based in northeast Scotland, which aimed to involve local people in a variety of river management related activities, including the implementation of a number of river restoration projects. The project originally developed from an increased public interest in the river in response to a perceived deterioration in water and habitat quality, most notably in terms of increased nutrient levels in the river waters, as a result of diffuse pollution. The extent of this public interest led to the project facilitating public participation throughout a series of actions designed to protect and enhance the river. This paper describes the project’s actions to involve local people in the river restoration element of the Ythan Project and looks at some of the wider lessons learnt during this process and their relevance to the implementation of the Water Framework Directive in Europe.
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Institutional drivers and constraints of floodplain restoration in Europe
By TIMOTHY MOSS
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The task of restoring floodplains, as a means of improving flood protection or providing other benefits, poses multi-dimensional challenges to policymakers and project managers alike. Involving essentially a reconfiguration of the interaction between a river and adjacent low-lying land, floodplain restoration affects a wide range of institutions designed to secure a variety of private and public goods associated with water and land use. A scheme to restore a floodplain requires the successful enrolment of these institutions in such a way as to create a result acceptable to the principal stakeholders. This is a highly complex process. This paper, based on EU-funded research on the policy contexts and selected pilot schemes of floodplain restoration in Germany, France and England and Wales, provides a critical appraisal of the institutional drivers and constraints of floodplain restoration. In particular, it explores how recent shifts in problem awareness and problem-solving in a number of relevant policy fields are creating windows of opportunity for more integrated approaches to restoring floodplains but problematises the emergence of a new policy delivery gap emanating from the growing complexity of new generation floodplain restoration schemes.
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Selecting fluvial geomorphological methods for river management including catchment scale restoration within the Environment Agency of England and Wales
By JIM WALKER, JONTY GIBSON, DAVID BROWN.
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There is a wide diversity of methods for applying fluvial geomorphological techniques to river management within the UK. This paper describes the application of such methods to river management issues at local and national scales, and offers guidance on the application of methods to morphological improvement, restoration and other management issues at the catchment scale. Background is given on the role and development of fluvial geomorphology within UK river management, and the role of recent legislative drivers is reviewed. The scope of current fluvial geomorphological methods which have been applied to river restoration within the Environment Agency over the last decade is described. The processes developed in this paper are drawn from existing Environment Agency guidance, nationally standardised methodologies and, to a limited extent, good practice from other UK sources. At the national scale a framework for developing fluvial geomorphological assessments using desk-based analysis of map and remote sensed data is proposed. At the catchment scale a three-tier system of fluvial geomorphological assessment is proposed for application to river restoration and management. This system provides increasing detail based upon the intensity of the required geomorphological output, and the objectives of the proposed assessment. Also considered are the cost and complexity of proposed activities, and the degree of environmental and economic risk associated with such activities. Methods at a local scale are separated into two tiers; general site assessments that constitute rapid fluvial geomorphological appraisals and geomorphological dynamics assessments that entail a much deeper degree of study. Finally, the future challenges which must be addressed in order to develop and improve the application of fluvial geomorphology to river restoration and management in the Environment Agency are considered. In this context three key issues are apparent; the standardisation of methods, the national collation of data, and the consistency of application of the various approaches.
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River restoration in the UK: Meeting the dual needs of the European Union Water Framework Directive and flood defence?
By GERALDENE WHARTON, DAVID J. GILVEAR.
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A major component of river restoration is the recreation of instream physical habitat heterogeneity and re-establishment of the linkage between the in-channel and adjacent floodplain environment. Re-engineering channels to reinstate a more natural form and the restoration of water and sediment transfer can bring multiple benefits particularly if undertaken as part of an environmental strategy for the whole catchment. The benefits usually include improvements to the ecological quality of rivers and reductions in the severity of flooding downstream. These benefits are achievable because rivers in their natural state are ecosystems that maintain high bio-diversity, floodplains when inundated attenuate flows, and flooding of low-lying areas creates wetlands and washlands of high nature conservation value and flood storage potential. This paper will explore (i) how the European Union Water Framework Directive (WFD) (EC, 2000) will become an increasingly important driver for catchment-based river restoration in the UK, and (ii) how river restoration has the potential to deliver ecological improvements in rivers consistent with WFD targets whilst, at the same time, providing more sustainable flood management.
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Examination of FST-hemispheres for evaluating boundary shear stress in streams
By XIAOLIN WANG, BETTINA BOCKELMANN-EVANS, DONGFANG LIANG.
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In recent years the Fliesswasserstammtisch (FST)-hemispheres have been used increasingly as a device to measure the in-situ bed shear stress for stream restoration. These hemispheres provide a convenient way of estimating the hydraulic characteristics in the near-bed region, which are often needed in river basin management. FST-hemispheres are especially designed for use in the field by environmental engineers and scientists and ecologists. This paper studies the scope and feasibility of using the FST-hemispheres method from the hydraulics perspective. Experiments have been undertaken using FST-hemispheres in a laboratory flume and the results have been compared with published data. Shortcomings have been found in the use of the FST-hemispheres as a means of measuring the boundary shear stress, for which they were originally designed. Through an analysis of the forces acting on the hemispheres in the flow, it has been shown that the FST-hemispheres are more appropriate for use in estimating the flow velocity. The bed shear stress can be related to the near-bed velocity by a bed friction coefficient and thus can be measured indirectly by the hemispheres. Some preliminary numerical model simulations of the flow around a hemisphere have been performed and confirm the aforementioned force-balancing analysis.
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JRBM vol 5 Issue 3

Introduction: Dams, ecosystems and livelihoods
By Jackie King and Matthew McCartney
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Decision support systems for environmental flows: Lessons from Southern Africa
By Cate Brown and Peter Watson
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The decision by a number of countries to re-engage with large dams creates an obligation to ensure that the attendant environmental and social consequences are dealt with adequately. In this regard, the key challenges for the future are the assessment and management of downstream environmental and social impacts. The paper examines these issues in the context of southern Africa, particularly the Lesotho HighlandsWater Project. It examines the ways in which Environmental Flows can affect the environment and the livelihoods of riparians, the need to make trade-offs between different uses of the water, and the difficulties of making trade-offs if the values of stakeholders regarding water use are not supported by a legal framework. The paper highlights the need to undertake environmental flow work early in the project cycle as part of the Environmental Impact Assessment, and the need to integrate environmental flow factors into the project’s economic analysis. It explores the financial trade-offs that are implicit in environmental flow work, the need for a multi-disciplinary team to carry out the work, and the need for a transparent decision framework. Finally, the importance of establishing a decision support system for use during the operational phases of the project is highlighted.
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Decision support systems for managing the water resources of the Komati River Basin
By Enoch M. Dlamini
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The Komati River Basin is a trans-boundary watercourse shared by the Republic of South Africa (RSA), the Kingdom of Swaziland (KoS) and the Republic of Mozambique. The Komati Basin Water Authority (KOBWA) is charged with the management of the river basin under a treaty signed between RSA and Swaziland of which consent was given by Mozambique in a separate Agreement. KOBWA developed Decision Support Systems (DSS) to manage the system. These include DSS for: (i) long-term water allocation (yield model) between the countries, (ii) short-term water allocation (rationing model), and (iii) day-to-day water release (hydraulics model). An extensive water-monitoring program has been put in place to improve the effectiveness of these DSSs. There has been a wide acceptance of the DSS by the users in the basin since the DSSs enable water users and water managers to make transparent water management decisions. This paper describes the three DSSs including the institutional framework on which these are applied.
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South African Multi-Stakeholder Initiative in Formulating Policy on Dams and Development
By Liane Greeff
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Following the release of the World Commission on Dams Report in November 2000: “Dams and Development A New Framework for Decision Making” a challenge was issued: “We have told our story: What happens next is up to you”. In July 2001, South Africa took up this challenge with the hosting of a Multi-stakeholder Symposium on the WCD. At this Symposium, South African stakeholders accepted the core values and approaches and declared themselves to be broadly supportive of the strategic priorities outlined in the WCD report, but believed that the guidelines needed to be contextualised in the South African situation. This resulted in the three-year South African Multi-stakeholder Initiative on the WCD Report, and culminated in the Final Report entitled: Applying the WCD Report in South Africa. This paper will share with the reader both the content of the South African Report as well as the remarkable process that enabled polarised perspectives to reach consensus on a broad range of controversial issues. It is this process which has been internationally recognised as a model for multi-stakeholder participation in policy formulation.
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Dams, health, and livelihoods: Lessons from the Senegal, suggestions for Africa
By Jonathan Lautze and Paul Kirshen
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Efforts in previous decades, largely culminating in the release of theWorld Commission on Dams Report [44], have engendered a more circumspect approach to dam construction and operations – one which incorporates consideration for the environment, health, equity, stakeholders, and livelihoods. Such integration nevertheless often remains at a rhetorical level, preventing tangible incorporation of these factors into Decision Support Tools (DSTs) for water management at a basin or sub-basin level. This paper uses the experience of the Senegal River Basin (SRB) to generate suggestions for how public health and smallholder livelihood concerns can be explicitly and quantitatively incorporated into dam planning and operations decisions in Africa’s other basins. The study examines the operational tradeoffs made among livelihoods, health, and more conventional water needs such as irrigation and hydropower in SRB water management strategies over the last two decades. The examination of these tradeoffs is used to develop common health and economic metrics to aid water management decisions. In conclusion, suggestions are made for how utilization of these common metrics can enable DSTs in Africa’s other basins to incorporate public health and smallholder livelihood parameters into dam planning and operations decisions.
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The state of the Colorado River ecosystem in Grand Canyon: Lessons from 10 years of adaptive ecosystem management
By Jeff Lovich and Theodore S. Melis
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The year 2005 marked the 10th anniversary of the completion of the Final Environmental Impact Statement (EIS) on the Operation of Glen Canyon Dam on the Colorado River, USA. A decade of research and monitoring provides an important milestone to evaluate the effects of dam operations on resources of concern and determine whether or not the desired outcomes are being achieved, or if they are even compatible with one another or not. A comprehensive effort was undertaken to assess the scientific state of knowledge of resources of concern, as identified in the EIS. The result was the first systematic attempt by scientists to conduct an assessment of the changing state of Colorado River ecosystem resources in Grand Canyon over a decadal timeframe. In the EIS, 30 resource attributes are listed along with predictions for how those resources would respond under the Secretary of the Interior’s 1996 Record of Decision, an operating prescription based on the preferred alternative of Modified Low-Fluctuating Flows (MLFF). Because of a lack of data or subsequent analyses to confirm whether some predictions stated in the EIS were correct, or not, 14 or 47 percent of the outcomes, are essentially unknown. Excluding outcomes that are unclear, then the remaining predictions in the EIS were correct in 7 out of 16 outcomes, or 44 percent of the categories listed. Mixed outcomes occur in 4 out of 16, or 25 percent of the categories, and failed predictions, occur in 5 out of 16, or 31 percent of the categories. As such, less than 50 percent of the outcomes were predicted correctly, underscoring the uncertainties associated with working in a large complex system with few to no long-term data sets. Similar uncertainties are faced by all resource managers charged with ecosystem restoration globally. The acceptability of this kind of uncertainty is influenced by interpretation, societal values, agency missions and mandates, and other factors. However, failure to correctly predict the future, in and of itself, is not deleterious under the paradigm of adaptive management where large uncertainties provide opportunities for learning and adjustment through an iterative process of “learning-bydoing” (Walters and Holling, 1990). Although recent science has documented a continued decline of environmental resources of the Colorado River below Glen Canyon Dam, it has also identified options that might still be implemented by managers to achieved desired future conditions in Grand Canyon.
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Quantifying well-being values of environmental flows for equitable decision-making: A case study of the Hamoun wetlands in Iran
By K.S. Meijer and S. Hajiamiri
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Construction of dams and reservoirs affects various groups of people. People who are often the losers from construction and operation of dams are the users of downstream ecosystems. To consider the needs of these people inwater resources decision-making, the relationships betweenwater, ecosystem and human well-being need to be assessed. This should lead to quantified criteria scores to support the decision-maker. Current environmental flow assessment methods focus on the relationship between water and ecosystems, but leave a gap where quantifiable criteria on human well-being are concerned. This paper discusses an approach for quantifying the effect of changed flow regimes on human well-being in an Integrated Water Resources Management study in Iran. The study shows the different effects on different groups of people, and in this way contributes to the consideration of social equity in decision-making in IntegratedWater Resources Management.
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Monetary benefit sharing from dams: A few examples of financial partnerships with Indigenous communities in Québec (Canada)
By Dominique Égré, Vincent Roquet and Carine Durocher
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Development practitioners have long recognised that the undeniable benefits of infrastructure projects based upon resource extractive activities, such as dam projects, often carry an associated price tag in terms of environmental and socio-economic impacts on communities in their area of influence and on taxpayers in general. Beyond the mitigation and compensation of negative impacts, sponsors increasingly recognise the need for directly sharing project benefits with local communities. The economic rationale for benefit sharing is the existence of an economic rent. Other justifications for benefit sharing include: (a) the need for fair redistribution of benefits to negatively affected populations; and (b) the need for financing development investments over and above mandatory compensation for damages and losses. These issues need to be considered in decision support systems designed for planning dams. This article discusses mechanisms that ensure a direct monetary redistribution of project-related revenues or profits from dam projects to local populations. A review of international case studies reveals that such mechanisms may pursue one or several of the following objectives: (a) providing additional long-term compensation to affected populations; (b) establishing a partnership with local communities based on sharing of the economic rent generated by the dam project; and (c) establishing long-term regional development funds. The review also reveals that the following five types of mechanisms may be considered: (a) revenue sharing; (b) development funds; (c) equity sharing; (d) taxes paid to local or regional authorities; and (e) preferential electricity rates and other water-related fees. The article illustrates the revenue sharing and equity sharing forms of benefit sharing mechanisms with two examples of financial partnerships with Indigenous communities in the province of Québec, Canada: the Paix des Braves Agreement between the Government of Québec and the Grand Council of the Crees and the Minashtuk project.
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Licensing for dam construction and operation – Practical decision support developed and improved over 100 years
By Bjørn Wold, Rune Flatby, Thomas Konow and Kristian Løkke
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During the last 100 years some 2500 dams have been built in Norway either related to irrigation, domestic and industrial water supply, or hydropower development projects, the latter being the dominant. A legal and regulatory system has been developed and amended to serve the ever changing policies and needs of a country that during the last century has been transformed from one of the poorest in Europe into one of the richest in the world. The needs and interest of the affected local population and their rightful share of the benefits of the hydropower development project have been taken care of in various ways over the years, from providing new houses and electricity, to the construction of new roads and even direct payments. The dams normally constructed in relation to these projects are monumental structures built to last for a very long time, some would say forever. In order to avoid dambreaks and thereby assure public safety, a legal framework securing appropriate operational rules, compliance with technical requirements and periodic inspections of the dams is an absolute necessity. A transparent government licensing process, involving all public and other stakeholders, has all the time been considered of crucial importance in order to achieve general acceptance of a project. The process includes comprehensive impact studies on environmental and social issues, as well as appropriate technical and political issues related to the eventual implementation of the project. Granting of a license should be based on a clear and unambiguous conclusion that the total benefits of the project exceed the negative impacts. The license includes explicit conditions stating a set of operating rules and other precautions that assure technical safety and environmental sustainability. All conditions is subject to future revisions.
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JRBM vol 5 Issue 4

Development of an unsteady model for flow through coarse eterogeneous porous media applicable to valley fills
By S.M. Hosseini and D.M. Joy
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A one-dimensional numerical model, ROCKFLOW, has been developed to analyze unsteady non-linear flow through coarse porous media. The model is particularly applicable to flow through valley fills and rock drains resulting from mining operations and takes factors such as the spatial variability of material properties and the variability of the cross-sectional geometry into account. The modified Saint-Venant equations together with the Forchheimer equation constitute the mathematical formulation of the flow system. The model employs a four-point finite difference method and a Newton-Raphson scheme to solve the resulting non-linear equations. With regard to the vertical heterogeneity of the materials, a superposition method has been developed and used in the model to account for changes in material properties. Laboratory studies on three, 1.5 m long, rockfills made of different homogeneous materials and also a layered rockfill were used to verify the model under different initial and boundary conditions. First, the material hydraulic parameters were determined using steady-state conditions in the physical models. The resulting hydraulic parameters were then used to model unsteady conditions. It was found that the model is able to reproduce the experimental results well in terms of both water surface profiles and depth variation with time curves in the physical models. There is a need to minimize the environmental impacts of mining activities. ROCKFLOW can be applied to valley fills under field conditions to test various design scenarios and to thereby assess their potential impact on the environment (e.g. modified flow regime in the downstream channel).
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Simulating the effect of invasive species on native freshwater mussel communities
By Y. Morales, L.J. Weber, A.E. Mynett, and T.J. Newton
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The dispersion of invasive species is a serious problem worldwide. In North America in particular, the introduction of the zebra mussel (Dreissenapolymorpha) has caused millions of dollars in economic losses and environmental damage. This paper uses ecohydraulics modeling to analyze the effects of zebra mussels on native freshwater mussel communities (unionids) in the Upper Mississippi River (UMR), USA. The model takes into account environmental forcing functions and individual mussel interactions in the form of food competition. First, hydrodynamic transport of incoming zebra mussel larvae was simulated to assess their colonization patterns on unionids. Next, population growth at various food availabilities was computed. Simulated zebra mussel densities were within the range observed in published studies and survival rates of unionids coincided with reported values for an upstream reach of the UMR. These results suggest that these two families of species may coexiste in the UMR, although the sharp decline in the unionid populations may eventually result in extirpation due to unsuccessful egg fertilization. This model provides the means for better understanding the interaction between native and invasive freshwater mussel species and it may be a valuable tool supporting the development of appropriate conservation strategies for unionids.
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Floods in the Meuse basin: Event descriptions and an international view on ongoing measures
By M.J.M. De Wit, H.A. Peeters, P.H. Gastaud, P. Dewil, K. Maeghe and J. Baumgart
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In recent years the frequency and magnitude of floods in the river Meuse has been relatively large. These floods have caused a lot of damage, but have also produced a lot of valuable information. The meteorological and hydrological conditions that caused these floods have been measured and analysed by different institutes in the different countries of the Meuse basin. The working group on Hydrology and Floods of the International Meuse Commission merged the data for the 1993, 1995, 2002 and 2003 flood events. This dataset has been used to analyse the general patterns that generate flood waves in the river Meuse. The analysis reveals that the hydrological response of the different sub-catchments strongly varies both in time and space. Another interesting observation is that separate flood waves occur at the same time at different stretches of the Meuse. Ideally, an integrated flood action plan for the Meuse aims at conserving or even enlarging the lag times between the different flood waves. Based on these observations the ongoing and proposed national measures to reduce flood damage risk in the Meuse and its tributaries are looked at from an international perspective.
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Derivation of total diffuse attenuation coefficient from water column temperature data and meteorological water surface fluxes: A simple management tool
By Sri Adiyanti and Jörg Imberger
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The total diffuse attenuation coefficient of Photosynthetically Available Radiation ( (PAR))is derived by optimising the solution of a surface layer model to match temperature profiles measured with a precision thermistor chain; a non-linear least-squares Levenberg-Marquardt scheme is applied to optimize Kd (PAR). The method was validated in Lake Kinneret (Israel) over 10 days in summer to early winter 2001, Valle de Bravo Reservoir (Mexico) on 1 July 2004 and Winam Gulf (Kenya) on 1 May and 12 August 2005. The method was applied for cases where the horizontal pressure gradient in the surface layer was negligible, the photic depth was deeper than the diurnal surface layer and the increment in temperature in photic region was considerably larger than the thermistor’s precision. In all these tests, the errors of the estimated values of Kd (PAR)were mostly within 10% of the actual direct measurements. Investigations of the sensitivity of the model revealed that the accuracy of the method depended primarily on the precision and accuracy of the thermistors as well as the vertical resolution of the temperature measurements in the surface layer; all of these determine the rate of convergence of the optimisation scheme.
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Contrasting the Middle Paraná and Mississippi Rivers to develop a template for restoring large floodplain river ecosystems
By John M. Nestler, Claudio R.M. Baigún, Noberto Oldani and Larry J. Weber
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Effective rehabilitation of large rivers requires a concept of normal floodplain river behavior – the reference condition - to understand system-level disturbance history and to develop plans to improve river health. However, reference conditions are difficult to obtain for large rivers. Using Correspondence Analysis of a select subset of the world’s great rivers, we show that the Paraná and Mississippi Rivers are relatively similar at the watershed scale based on general geographical and physico-chemical variables, although these rivers differ substantially in disturbance history.We believe that the less disturbed Paraná River provides reference conditions for the more disturbed Mississippi River for some processes and functions whereas the Mississippi River provides a compelling vision of the future state of the Paraná River unless sustainable development plans are developed and implemented. By integrating information between them, this pair of rivers provides a unique opportunity for scientists to develop more robust conceptual models and improved deterministic models to better guide river management and rehabilitation actions. We suggest that development of large river reference conditions may be better obtained through expanded inter-hemispheric scientific collaboration on multiple systems than through increased focus on a single impacted system.
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Numerical simulation of flow downstream of lock and dam
By J. P. Raiford and A. A. Khan
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A two-dimensional, depth-averaged flow model with the depth-averaged parabolic eddy viscosity, mixing length, and k - ε turbulent closure schemes is utilized to simulate flow pattern downstream of lock and dam structures. The accuracy of the computational model with three turbulent closure schemes is evaluated by comparing the simulated velocity patterns with the measured data in a physical model study of a lock and dam. The mixing length and k - ε schemes perform well in predicting the location and size of the recirculation zones observed in the physical model study. Also, these schemes are able to accurately predict the velocity profiles across the channel at various locations along the length of the channel. The results suggest that the mixing length scheme, though simple, performs satisfactorily in simulating the flow pattern downstream of a lock and dam. Finally, the model is applied to compute the flow pattern downstream of an actual lock and dam in the Red River, Louisiana that has been plagued with navigational problems. The model performs well in predicting the main flow features.
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Revised equations for manning’s coefficient for sand-bed rivers
By Aminuddin AB. Ghani, Nor Azazizakaria, Chang Chun Kiat, Junaidah Ariffin,
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The procedure for selecting values of Manning n is subjective and requires judgment and skill which are developed primarily through experience. Government agencies and private sectors in developed nations such as the USA are still doing research on predicting n values for rivers. Since flow and boundary roughness vary with river conditions, such research is therefore pertinent for rivers in Malaysia where floods are one of primary concerns. Research on Manning n value was started by River Engineering and Urban Drainage Research Centre (REDAC), Universiti Sains Malaysia (USM) since 2000 at the Kinta River catchment. Further data collections were later made at two other major rivers i.e. Langat River and Kulim River. Two new equations are proposed for determining Manning n for sand-bed rivers in Malaysia based on 163 data collected from these three rivers. On average, both equations have an error less than 10% in predicting flow discharge for all 163 data
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