Description:    Manning’s roughness coefficient ( n ) has been widely used in the estimation of flood discharges or depths of flow in natural channels. Therefore, the selection of appropriate Manning’s n values is of paramount importance for hydraulic engineers and hydrologists and requires considerable experience, although extensive guidelines are available. Generally, the largest source of error in post-flood estimates (termed indirect measurements) is due to estimates of Manning’s n values, particularly when there has been minimal field verification of flow resistance. This emphasizes the need to improve methods for estimating n values. The objective of this study was to develop a soft computing model in the estimation of the Manning’s n values using 75 discharge measurements on 21 high gradient streams in Colorado, USA. The data are from high gradient (S 〉 0.002 m/m), cobble- and boulder-bed streams for within bank flows. This study presents Gene-Expression Programming (GEP), an extension of Genetic Programming (GP), as an improved approach to estimate Manning’s roughness coefficient for high gradient streams. This study uses field data and assessed the potential of gene-expression programming (GEP) to estimate Manning’s n values. GEP is a search technique that automatically simplifies genetic programs during an evolutionary processes (or evolves) to obtain the most robust computer program (e.g., simplify mathematical expressions, decision trees, polynomial constructs, and logical expressions). Field measurements collected by Jarrett (J Hydraulic Eng ASCE 110: 1519–1539, 1984 ) were used to train the GEP network and evolve programs. The developed network and evolved programs were validated by using observations that were not involved in training. GEP and ANN-RBF (artificial neural network-radial basis function) models were found to be substantially more effective (e.g., R 2 for testing/validation of GEP and RBF-ANN is 0.745 and 0.65, respectively) than Jarrett’s (J Hydraulic Eng ASCE 110: 1519–1539, 1984 ) equation (R 2 for testing/validation equals 0.58) in predicting the Manning’s n . Content Type Journal Article Pages 1-15 DOI 10.1007/s11269-012-0211-1 Authors H. Md. Azamathulla, River Engineering and Urban Drainage Research Centre (REDAC), Universiti Sains Malaysia, Engineering Campus, Seri Ampangan, 14300 Nibong Tebal, Pulau Pinang, Malaysia Robert D. Jarrett, National Research Program, Paleohydrology and Climate Change, U.S. Geological Survey, P.O. Box 25046, MS412, Lakewood, CO 80225-0046, USA Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    Using China’s Lake Baiyangdian sub-basin for a case study, we developed an ecologically oriented dam release plan that can be used to define an optimal dam operation scheme that provides both the environmental flows required by bodies of water and wetlands downstream from the Xidayang Reservoir dam and enough water for agricultural, and industrial water users. In addition, we evaluated the benefits that might be provided by modifying releases of water from the reservoir. To attain ecological sustainability in the sub-basin, we used the supply for each water user as a decision variable based on three objectives: (1) to achieve sustainable socioeconomic development; (2) to keep the water volume as close as possible to the ideal environmental flows in the urban rivers of Baoding City; and (3) to keep the water amount as close as possible to Lake Baiyangdian’s ideal environmental water requirements. We used the ideal-point method to provide dimensionless values for the first objective, and then used a weighting method to integrate the three objectives into a single holistic goal. We then used the GAMS/CONOPT software to solve the nonlinear model and predict the optimal results. We discuss the optimal water allocation and ecologically oriented dam release plans for the three scenarios. To determine the limitations of the method, we performed a sensitivity analysis, and discuss the optimal results for different weightings of objectives provided by decision-makers. The results of the optimization analysis provide a set of effective compromises among the target objectives that can guide future management of water releases from the reservoir. Content Type Journal Article Pages 1-22 DOI 10.1007/s11269-012-0198-7 Authors Wei Yang, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, No. 19 Xinjiekouwai Street, Haidian District, Beijing, 10087 China Zhifeng Yang, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, No. 19 Xinjiekouwai Street, Haidian District, Beijing, 10087 China Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description: Erratum to: Developing Novel Approaches to Tracking Domestic Water Demand Under Uncertainty—A Reflection on the “Up Scaling” of Social Science Approaches in the United Kingdom Content Type Journal Article Category Erratum Pages 1-2 DOI 10.1007/s11269-012-0210-2 Authors Alison L. Browne, Lancaster Environment Centre, Lancaster University, Lancaster, UK LA1 4YQ Will Medd, Lancaster Environment Centre, Lancaster University, Lancaster, UK LA1 4YQ Ben Anderson, Centre for Research in Economic Sociology and Innovation, Essex University, Essex, UK Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    This study presents a geomorphology based semi-distributed methodology for prediction of runoff of a catchment. In this proposed methodology, the catchment area is divided into a number of sub-catchments using the Thiessen polygon method. The rainfall records of particular rain-gauge station are considered as uniformly distributed over the entire sub-watershed. Four different weighting factors are proposed to obtain the sub-catchment’s contribution towards runoff. The weighting factors are calculated based on the geomorphological parameters of the catchment. The geomorphological parameters of the sub-watersheds are obtained from SRTM digital elevation data. The weighted contributions from all the sub-watersheds at current and previous time steps and the previous time step discharge are used to develop an Artificial Neural Network (ANN) for predicting the discharge at the basin outlet. A lump model considering average rainfall of the catchment is also developed using ANN for evaluating the performance of the proposed distributed model. For the lump model, average rainfall is calculated using Thiessen polygon method. The historic rainfall and runoff data recorded at the Dikrong basin, a sub-catchment of the river Brahmaputra is used to evaluate the efficiency of the developed methodology. The evaluation results show that the presented model is superior to the lump model and has the potential for field application. A comparative study is also carried out to obtain the most influential combination of geomorphological parameters in predicting the catchment’s runoff. Content Type Journal Article Pages 1-13 DOI 10.1007/s11269-012-0202-2 Authors Rajib Kumar Bhattacharjya, Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati, India Sandeep Chaurasia, Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati, India Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    The potential revenues of water right transactions can be substantial in theory, but the actual receipts are generally limited in practice. This difference is attributable to the presence of other factors influencing the operation of water markets. In this paper, we study the discriminatory-price and the uniform-price sealed-bid procurement auction for divisible items in water right trade wherein commissions define the costs of transactions. We further analyze the quantitative relationships between transaction costs and the revenues of sellers, buyers, and of the auction site. The findings indicate that transaction costs do not affect the margins of bidders because of reluctance to raise quotations. The bidders bear the commissions but impose the transaction costs outwardly on the seller who as a result suffers from reduced revenues. Of the two types the uniform-price auction generates more revenue for sellers than the discriminatory-price auction. Content Type Journal Article Pages 1-10 DOI 10.1007/s11269-012-0197-8 Authors Li H. Zhang, The Pilot College Of Beijing University Of Technology, Beijing, 101101 The People’s Republic of China Shao F. Jia, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101 The People’s Republic of China Chi K. Leung, California State University, Fresno, Fresno, CA 93740, USA Li P. Guo, The Pilot College Of Beijing University Of Technology, Beijing, 101101 The People’s Republic of China Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    The paper investigates whether there is a statistically significant impact of short-term climate variables (specifically air temperature and rainfall) on residential water consumption at two selected case sites in the Czech Republic. The analysis is based on a unique time series of daily data from 2004–2009. The statistical methods used are CART methodology and a decomposition of these time series based on a locally weighted regression method. Apart from the data analysis results, the investigation raises several methodological questions regarding the use of daily data and the scope of analysis based on such data sets. Content Type Journal Article Pages 1-15 DOI 10.1007/s11269-012-0191-1 Authors Lenka Slavíková, IEEP, Institute for Economic and Environmental Policy, University of Economics in Prague, W. Churchill sq. 4, Praha 3, 130 67 Czech Republic Vítězslav Malý, IEEP, Institute for Economic and Environmental Policy, University of Economics in Prague, W. Churchill sq. 4, Praha 3, 130 67 Czech Republic Michael Rost, Department of Applied Mathematics and Informatics, Faculty of Economics, University of South Bohemia, Studentska 13, Ceske Budejovice, 370 05 Czech Republic Lubomír Petružela, T. G. Masaryk Water Research Institute, Podbabska 2582/30, Praha 6, 160 00 Czech Republic Ondřej Vojáček, IEEP, Institute for Economic and Environmental Policy, University of Economics in Prague, W. Churchill sq. 4, Praha 3, 130 67 Czech Republic Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    This paper attempts to measure the economic benefits of tap water supply services in some urban areas of Korea. According to micro-economic theory, the economic benefit of water consumed is the sum of the actual water price and the additional willingness to pay (WTP) for the consumption. We apply the dichotomous choice contingent valuation method to assess the additional WTP using specific cases of four cities located in the metropolitan area of Korea. Both parametric and non-parametric approaches to obtaining the mean WTP estimates are used. The results show that the mean additional WTP for the tap water supply service is estimated to be KRW 163.38 (USD 0.13) and KRW 223.89 (USD 0.18) per m 3 using parametric and non-parametric approaches, respectively. Given that the price of tap water is 641.66 per m 3 , the residents’ economic benefits that ensue from the tap water supply service are computed as KRW 805.04 (USD 0.63) and KRW 865.55 (USD 0.68) per m 3 , respectively. This information can be beneficially utilized in conducting an economic feasibility study for a new project related to tap water supply service. Content Type Journal Article Pages 1-9 DOI 10.1007/s11269-012-0206-y Authors Won-Seok Lee, Department of Civil, Environmental, and Architectural Engineering, Korea University, 145 Anam-Ro, Seongbuk-Ku, Seoul, 136-701 Korea Seung-Hoon Yoo, Graduate School of Energy & Environment, Seoul National University of Science and Technology, 232 Gongreung-Ro, Nowon-Ku, Seoul, 139-743 Republic of Korea Jeehyeong Kim, Department of Civil, Environmental, and Architectural Engineering, Korea University, 145 Anam-Ro, Seongbuk-Ku, Seoul, 136-701 Korea Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    Accurate estimation of wind speed is essential for many hydrological applications. One way to generate wind velocity is from the fifth generation PENN/NCAR MM5 mesoscale model. However, there is a problem in using wind speed data in hydrological processes due to large errors obtained from the mesoscale model MM5. The theme of this article has been focused on hybridization of MM5 with four mathematical models (two regression models- the multiple linear regression (MLR) and the nonlinear regression (NLR), and two artificial intelligence models – the artificial neural network (ANN) and the support vector machines (SVMs)) in such a way so that the properly modelled schemes reduce the wind speed errors with the information from other MM5 derived hydro-meteorological parameters. The forward selection method was employed as an input variable selection procedure to examine the model generalization errors. The input variables of this statistical analysis include wind speed, temperature, relative humidity, pressure, solar radiation and rainfall from the MM5. The proposed conjunction structure was calibrated and validated at the Brue catchment, Southwest of England. The study results show that relatively simple models like MLR are useful tools for positively altering the wind speed time series obtaining from the MM5 model. The SVM based hybrid scheme could make a better robust modelling framework capable of capturing the non-linear nature than that of the ANN based scheme. Although the proposed hybrid schemes are applied on error correction modelling in this study, there are further scopes for application in a wide range of areas in conjunction with any higher end models. Content Type Journal Article Pages 1-23 DOI 10.1007/s11269-012-0130-1 Authors Asnor Muizan Ishak, WEMRC, Department of Civil Engineering, University of Bristol, Bristol, BS81TR UK Renji Remesan, Department of Geography, University of Hull, Cottingham Road, Hull, HU6 7RX UK Prashant K. Srivastava, WEMRC, Department of Civil Engineering, University of Bristol, Bristol, BS81TR UK Tanvir Islam, WEMRC, Department of Civil Engineering, University of Bristol, Bristol, BS81TR UK Dawei Han, WEMRC, Department of Civil Engineering, University of Bristol, Bristol, BS81TR UK Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    Runoff, groundwater recharge and discharge, and surface water–groundwater interaction are the main driving forces of wetlands. The quantification of such flows is crucial information in the restoration and management of groundwater-dependent wetlands. The objective of this work is to quantify groundwater inflow at the level of the hydrogeological basin, which discharges into the wetland in the coastal plain of the Río de la Plata (Argentina). It also aims at evaluating whether such inflow is affected by groundwater exploitation in the high plain adjacent to the wetland. On the basis of water level data, a model of hydrological behaviour was developed and then a numerical simulation to quantify groundwater inflow was carried out. The evolution of groundwater levels was analyzed considering three situations: one of them in natural conditions and two others under different groundwater exploitation conditions. In the first case, the inflow originates in the recharge from precipitation, in the local groundwater discharge from the adjacent high plain and in the regional one from the semi-confined aquifer. The exploitation of the semi-confined aquifer in the high plain causes the formation of a cone of depression which modifies the hydrodynamics of the wetland in the area adjacent to the extraction wells. The quantification of flows shows that groundwater exploitation in areas of the basin located out of the wetland may cause the volume of water flowing into the wetland through groundwater discharge to decrease by approximately 25 %. The importance of considering discharge wetlands as part of regional hydrogeological systems should be highlighted, mainly as regards the management of natural resources. Content Type Journal Article Pages 1-11 DOI 10.1007/s11269-012-0216-9 Authors E. Carol, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata (UNLP), Calle 64 #3, 1900, La Plata, Argentina E. Kruse, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata (UNLP), Calle 64 #3, 1900, La Plata, Argentina M. Mancuso, Laboratório Nacional de Engenharia Civil (LNEC), Lisboa, Portugal M. Melo, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata (UNLP), Calle 64 #3, 1900, La Plata, Argentina Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741

Description:    Socio-economic change, severe droughts, and environmental concerns focus attention on sustainability of water supplies and the ability of water utilities to meet levels of service. Traditionally, water management has been supply-side dominated and long-term demand forecasting has received relatively little attention. However, it is increasingly recognised that water demand management could be a ‘low regret’ adaptation measure (both financially and environmentally) given large uncertainties about future non-climate and climate pressures. This paper begins with a brief history of household water demand management in the UK. We then review approaches to water demand estimation and forecasting over the short- (daily to season) and long-term (years to decade) and note the paucity of studies on weather and climate. We discuss peak household water use behaviours identified from metering trials, micro-component diary-based studies, and statistical techniques for long-term demand forecasting. We refer to the Anglian Water Services (AWS) ‘Golden 100’ data to illustrate the significant practical and conceptual issues faced when mining household water use data for weather signals, especially when the data are noisy and originally intended for other applications. Further research is needed into the relationships between climate variables and household micro-component water use, especially for peak demands. Content Type Journal Article Pages 1-31 DOI 10.1007/s11269-012-0190-2 Authors Joanne M. Parker, Department of Geography, Centre for Hydrological and Ecosystem Science (CHES), Loughborough University, Loughborough, LE11 3TU UK Robert L. Wilby, Department of Geography, Centre for Hydrological and Ecosystem Science (CHES), Loughborough University, Loughborough, LE11 3TU UK Journal Water Resources Management Online ISSN 1573-1650 Print ISSN 0920-4741