This study investigates the patterns that describe reliability of water distribution networks focusing to the node connectivity, energy balance, and economics of construction, operation and maintenance. A number of measures to evaluate the network resilience has been developed and assessed to arrive at more accurate diagnostics of regular and irregular demand scenarios. These measures have been proposed as a part of the methodology for snap-shot assessment of network reliability based on its configuration and hydraulic performance. Practical outcome of the research is the decision support tool for reliability-based design of water distribution networks. This computer package named NEDRA (NEtwork Design and Reliability Assessment) consists of the modules for network generation, filtering, initialisation, optimisation, diagnostics and cost calculation, which can be used for sensitivity analyses of single network layout or assessments of multiple layouts. The study concludes that none of the analysed aspects develops clear singular patterns. Nevertheless, the proposed network buffer index (NBI) and the hydraulic reliability diagram (HRD) as visual representation of the network resilience give sufficient snap-shot pointing the composition of the index value, and displaying possible weak points in the network that can be hidden behind the averaged values of various reliability measures.

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.

Knowing how to manage the losses from water supply networks and how to get to the next level in bettering your system is a major problem and one that is most common in the majority of water companies worldwide. Sometimes water companies set their sights too high and cannot deliver due to non-realistic targets setting. Of course this is considered or seen as a failure within the company or country when it is really just exceeding expectations of what can be delivered. The aim of System Losses from Water Supply Networks is to assist water companies to identify where they are on the ‘water loss ladder’ and what is required to move to the next level. The book will provide an understanding of what the water companies need to achieve and where they should be aiming for in their efforts to reduce water losses. The book provides useful and practical information on non-revenue water (NRW) issues and solutions enriched with relevant case studies.

Focusing primarily on understanding the steady-state hydraulics that form the basis of hydraulic design and computer modelling applied in water distribution, Introduction to Urban Water Distribution elaborates the general principles and practices of water distribution in a straightforward way. The workshop problems and design exercise develop a temporal and spatial perception of the main hydraulic parameters in the system for given layout and demand scenarios. Furthermore, the book contains a detailed discussion of water demand, which is a fundamental element of any network analysis, and principles of network construction, operation, and maintenance. The attached CD contains all spreadsheet applications mentioned in the text, and the network model used in the design exercise. Written in a manner that is easily understood by those who know little about the subject, this introductory text will also benefit experts dealing with advanced problems who wish to refresh their knowledge.

Analysis of a Water Distribution Network may be necessary to know its behaviour under normal and deficient conditions and the design of a new network. Various methods such as Hardy Cross, Newton-Raphson, Linear Theory, and Gradient for static and time-dependent (extended period) analyses are described with small illustrative examples. The book also covers analysis considering withdrawal along links, head-dependent and performance-based analyses, calibration of existing networks, water quality modeling, analysis considering uncertainty of parameters, and reliability analysis of water distribution networks. Brief description of available computer softwares is also given.