The papers in this volume were originally presented at the 18th European Junior Scientists Workshop (EJSW), Portugal, on 8-11 November 2003 and at the 1st Asian Junior Scientists Workshop (AJSW), Malaysia, on 7-10 February 2004. The workshops were organised by the SS&PWG (Sewer Systems and Processes Working Group) of the IWA/IAHR Joint Committee on Urban Drainage. The two separate workshops were convened under the general themes of "Sewer Processes, Networks and Urban Drainage" and specific topics covered included integrated modelling of urban water systems; modelling of pollutant loads; calibration of models; bed-load transport; sewer pipe roughness; advection in sewers; anoxic processes; infiltration and exfiltration; runoff source control; pollutant loads; ventilation and oxygen uptake. From the 37 full papers presented at the two workshops, 16 papers have been selected by independent reviewers from the SS&PWG for publication in Sewer Networks and Processes within Urban Water Systems. They reflect rather well the variety of topics presented during both workshops, and bring the high-quality work of these junior authors to the wider audience it merits.

Sewer systems constitute a very significant heritage in European cities. Their structural quality and functional efficiency are key parameters to guarantee the transfer of domestic and industrial wastewater to treatment plants without infiltration nor exfiltration. Infiltration of groundwater is particularly detrimental to treatment plant efficiency, while exfiltration of wastewater can lead to groundwater contamination. The European research project APUSS (Assessing infiltration and exfiltration on the Performance of Urban Sewer Systems) was devoted to sewer infiltration and exfiltration questions. It was structured in three main Work Areas dealing respectively with i) the development of new measurement methods based on tracer experiments and accounting for detailed uncertainty analyses, ii) the implementation of models and software tools to integrate structural and experimental data and to facilitate data display, operational management and decision-making processes and iii) the integration of economic and operational questions by means of cost estimation, economic evaluation, performance indicators and multi-criteria methods applied to investment/rehabilitation strategies. This final report describes the objectives, methods and main results for each Work Area. References to detailed methods, protocols, reports and tools are given in this final report which will be an invaluable source of information for all those concerned with the performance of urban sewer systems.

In the quest to reduce costs and improve the efficiency of water and wastewater services, many communities in the United States are exploring the potential advantages of privatization of those services. Unlike other utility services, local governments have generally assumed responsibility for providing water services. Privatization of such services can include the outright sale of system assets, or various forms of public-private partnershipsâ€"from the simple provision of supplies and services, to private design construction and operation of treatment plants and distribution systems. Many factors are contributing to the growing interest in the privatization of water services. Higher operating costs, more stringent federal water quality and waste effluent standards, greater customer demands for quality and reliability, and an aging water delivery and wastewater collection and treatment infrastructure are all challenging municipalities that may be short of funds or technical capabilities. For municipalities with limited capacities to meet these challenges, privatization can be a viable alternative. Privatization of Water Services evaluates the fiscal and policy implications of privatization, scenarios in which privatization works best, and the efficiencies that may be gained by contracting with private water utilities.

This book is open access under a CC BY-NC 4.0 license. This revised, updated textbook presents a systems approach to the planning, management, and operation of water resources infrastructure in the environment. Previously published in 2005 by UNESCO and Deltares (Delft Hydraulics at the time), this new edition, written again with contributions from Jery R. Stedinger, Jozef P. M. Dijkman, and Monique T. Villars, is aimed equally at students and professionals. It introduces readers to the concept of viewing issues involving water resources as a system of multiple interacting components and scales. It offers guidelines for initiating and carrying out water resource system planning and management projects. It introduces alternative optimization, simulation, and statistical methods useful for project identification, design, siting, operation and evaluation and for studying post-planning issues. The authors cover both basin-wide and urban water issues and present ways of identifying and evaluating alternatives for addressing multiple-purpose and multi-objective water quantity and quality management challenges. Reinforced with cases studies, exercises, and media supplements throughout, the text is ideal for upper-level undergraduate and graduate courses in water resource planning and management as well as for practicing planners and engineers in the field.

This book addresses the latest research advances, innovations, and applications in the field of urban drainage and water management as presented by leading researchers, scientists and practitioners from around the world at the 11th International Conference on Urban Drainage Modelling (UDM), held in Palermo, Italy from 23 to 26 September, 2018. The conference was promoted and organized by the University of Palermo, Italy and the International Working Group on Data and Models, with the support of four of the world’s leading organizations in the water sector: the International Water Association (IWA), International Association for Hydro-Environment Engineering and Research (IAHR), Environmental & Water Resources Institute (EWRI) - ASCE, and the International Environmental Modelling and Software Society (iEMSs). The topics covered are highly diverse and include drainage and impact mitigation, water quality, rainfall in urban areas, urban hydrologic and hydraulic processes, tools, techniques and analysis in urban drainage modelling, modelling interactions and integrated systems, transport and sewer processes (incl. micropollutants and pathogens), and water management and climate change. The conference’s primary goal is to offer a forum for promoting discussions amongst scientists and professionals on the interrelationships between the entire water cycle, environment and society.

Protecting and maintaining water distributions systems is crucial to ensuring high quality drinking water. Distribution systems-consisting of pipes, pumps, valves, storage tanks, reservoirs, meters, fittings, and other hydraulic appurtenances-carry drinking water from a centralized treatment plant or well supplies to consumers' taps. Spanning almost 1 million miles in the United States, distribution systems represent the vast majority of physical infrastructure for water supplies, and thus constitute the primary management challenge from both an operational and public health standpoint. Recent data on waterborne disease outbreaks suggest that distribution systems remain a source of contamination that has yet to be fully addressed. This report evaluates approaches for risk characterization and recent data, and it identifies a variety of strategies that could be considered to reduce the risks posed by water-quality deteriorating events in distribution systems. Particular attention is given to backflow events via cross connections, the potential for contamination of the distribution system during construction and repair activities, maintenance of storage facilities, and the role of premise plumbing in public health risk. The report also identifies advances in detection, monitoring and modeling, analytical methods, and research and development opportunities that will enable the water supply industry to further reduce risks associated with drinking water distribution systems.

Mathematical Modelling and Computer Simulation of Activated Sludge Systems – Second Edition provides, from the process engineering perspective, a comprehensive and up-to-date overview regarding various aspects of the mechanistic (“white box”) modelling and simulation of advanced activated sludge systems performing biological nutrient removal. In the new edition of the book, a special focus is given to nitrogen removal and the latest developments in modelling the innovative nitrogen removal processes. Furthermore, a new section on micropollutant removal has been added. The focus of modelling has been shifting in the last years to models that can describe the performance of a whole plant (plant-wide modelling). The expanded part of this new edition introduces models describing the most important processes interrelated with the mainstream activated sludge systems as well as models describing the energy balance, operating costs and environmental impact. The complex process evaluation, including minimization of energy consumption and carbon footprint, is in line with the present and future wastewater treatment goals. By combining a general introduction and a textbook, this book serves both intermediate and more experienced model users, both researchers and practitioners, as a comprehensive guide to modelling and simulation studies. The book can be used as a supplemental material at graduate and post-graduate levels of wastewater engineering/modelling courses.