Assessing Infiltration And Exfiltration On The Performance Of Urban Sewer Systems

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.

During the period 2001-2004, the European research project APUSS (Assessing infiltration and exfiltration on the Performance of Urban Sewer Systems) was devoted to sewer infiltration and exfiltration questions. This synthetic final report describes the objectives, methods and main results for each Work Area. During the period 2001-2004, the European research project APUSS (Assessing infiltration and exfiltration on the Performance of Urban Sewer Systems) was devoted to sewer infiltration and exfiltration questions. This synthetic final report describes the objectives, methods and main results for each Work Area.

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.

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.

Water utilities worldwide lose 128 billion cubic meters annually, causing annual monetary losses estimated at USD 40 billion. Most of these losses occur in developing countries (74%). This calls for rethinking the challenges facing water utilities in developing countries, foremost of which is the assessment of water losses in intermittent supply networks. Water loss assessment methods were originally developed in continuous supply systems, and their application in intermittently operated networks (in developing countries) is hindered by the widespread use of household water tanks and unauthorised consumption. This study provides an extensive review of existing methods and (software) tools for water loss assessment. In addition, several new methods were developed, which offer improved water loss assessment in intermittent supply. As the volume of water loss varies monthly and annually according to the amount of supplied water, this study proposes procedures to normalise the volume of water loss in order to enable water utilities to monitor and benchmark their performance on water loss management. The study also developed a novel method of estimating apparent losses using routine data of WWTP inflows, enabling future real-time monitoring of losses in networks. Different methods have also been suggested to estimate the unauthorised consumption in networks. This study found that minimum night flow analysis can still be applied in intermittent supply if an area of the network is supplied for several days. Furthermore, this study concluded that water meter performance is enhanced in intermittent supply conditions. However, continuous supply in the presence of float-valves significantly reduces the accuracy of water meters. Finally, this study provides guidance and highlights several knowledge gaps in order to improve the accuracy of water loss assessment in intermittent supply. Accurate assessment of water loss is a prerequisite for reliable leakage modelling and minimisation as well as planning for, and monitoring of water loss management in distribution networks.

This new edition of a well-established textbook covers the environmental and engineering aspects of the management of rainwater and wastewater in areas of human development. Urban Drainage deals comprehensively not only with the design of new systems, but also the analysis and upgrading of existing infrastructure. Keeping its balance of principles, practice and research, this new edition has significant new material on modelling, resilience, smart systems, and the global and local context. The two new authors bring further research and practice-based experience. This is an essential text for undergraduate and graduate students, lecturers and researchers in water engineering, environmental engineering, public health engineering, engineering hydrology, and related non-engineering disciplines. It also serves as a dependable reference for drainage engineers in water service providers, local authorities, and for consulting engineers. Extensive examples are used to support and demonstrate the key issues throughout the text.

Water and Wastewater companies operating all around the world have faced rising asset management and replacement costs, often to levels that are financially unsustainable. Management of investment needs, while meeting regulatory and other goals, has required: A better understanding of what customers demand from the services they pay for, and the extent to which they are willing to pay for improvements or be compensated for a reduction in performance Development of models to predict asset failure and to identify and concentrate investment on critical assets Improved management systems Improved accounting for costs and benefits and their incorporation within an appropriate cost-benefit framework Incorporation of risk management techniques Utilisation of advanced maintenance techniques including new rehabilitation failure detection technologies Enhancements in pipeline materials, technologies and laying techniques. These papers developed from LESAM 2007 for inclusion in Strategic Asset Management of Water Supply and Wastewater Infrastructures are focused on the techniques, technologies and management approaches aiming at optimising the investment in infrastructure while achieving demanded customer service standards, and they provide an opportunity to gain access to the latest discussion and developments at the leading-edge in this field. This book will be essential reading for utility operators and managers, regulators and consultants.