State Of Technology For Rehabilitation Of Water Distribution Systems

The impact that the lack of investment in water infrastructure will have on the performance of aging underground infrastructure over time is well documented and the needed funding estimates range as high as $325 billion over the next 20 years. With the current annual replacement rate averaging 0.5%, pipes would be expected to last for 200 years, but most pipes are designed for 50 or 100 year life cycles. While this replacement rate may be sufficient in the immediate term because pipes are still relatively young, as systems grow older, the necessary replacement rates will inevitably increase. In addition to the necessary funding, congestion above and below ground is making the replacement of water mains more difficult for utility owners as is the lack of public tolerance for the disruption caused by construction work. There is an increasing availability of technologies for rehabilitation of existing pipes, which provides solutions that minimize or alleviate these problems, while providing realistic and potentially cost-effective alternatives to traditional open cut replacement.

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.

Pipe failures in water distribution systems can have a serious impact and hence it’s important to maintain the condition and integrity of the distribution system. This book presents a whole-life cost optimisation model for the rehabilitation of water distribution systems. It combines a pipe breakage number prediction model with a pipe criticality assessment model, which enables the creation of a well-constructed and more tightly constrained optimisation model. The pipe breakage number prediction model combines information on the physical characteristics of the pipes with historical information on breakage and failure rates. A weighted multiple nonlinear regression analysis is applied to describe the condition of different pipe groups. The criticality assessment model combines a pipe’s condition with its hydraulic significance through a modified TOPSIS. This model enables the optimisation to focus its efforts on those important pipes. The whole life cost optimal rehabilitation model is a multiple-objective and multiple-stage model, which provides a suite of rehabilitation decisions that minimise the whole life cost while maximising its long-term performance. The optimisation model is solved using a modified NSGA-II. The utility of the developed models is that it allows decision makers to prioritize their rehabilitation strategy in a proactive and cost-effective manner.

This report is a synthesis of knowledge and includ

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Annotation All-in-one, state-of-the-art guide to safe drinking water Civil engineers and anyone else involved in any way with the design, analysis, operation, maintenance or rehabilitation of water distribution systems will find practical guidance in Water Distribution SystemsHandbook. Experts selected by Handbook editor Larry W. Mays provide historical, present day, and future perspectives, as well as state-of-the-art details previously available only in specialized journals. You get a comprehensively detailed exploration of every facet of the hydraulics ofpressurized flow; piping design and pipeline systems; storage issues; reliability analysis and distribution, and more. Detailed information on the latest technology contributions and on enhancements to the EPANETmodel are included. You'll also find case studies that range from the small municipal systems found in every U.S. town, to large systems common to great urban centers like New York, London and Paris.

All-in-one, state-of-the-art guide to safe drinking water Civil engineers and anyone else involved in any way with the design, analysis, operation, maintenance or rehabilitation of water distribution systems will find practical guidance in Water Distribution Systems Handbook. Experts selected by Handbook editor Larry W. Mays provide historical, present day, and future perspectives, as well as state-of-the-art details previously available only in specialized journals. You get a comprehensively detailed exploration of every facet of the hydraulics of pressurized flow; piping design and pipeline systems; storage issues; reliability analysis and distribution, and more. Detailed information on the latest technology contributions and on enhancements to the EPANET model are included. You'll also find case studies that range from the small municipal systems found in every U.S. town, to large systems common to great urban centers like New York, London and Paris.

This book is a printed edition of the Special Issue "Advanced Hydroinformatic Techniques for the Simulation and Analysis of Water Supply and Distribution Systems" that was published in Water

Comprehensive Water Quality and Purification, Four Volume Set provides a rich source of methods for analyzing water to assure its safety from natural and deliberate contaminants, including those that are added because of carelessness of human endeavors. Human development has great impact on water quality, and new contaminants are emerging every day. The issues of sampling for water analysis, regulatory considerations, and forensics in water quality and purity investigations are covered in detail. Microbial as well as chemical contaminations from inorganic compounds, radionuclides, volatile and semivolatile compounds, disinfectants, herbicides, and pharmaceuticals, including endocrine disruptors, are treated extensively. Researchers must be aware of all sources of contamination and know how to prescribe techniques for removing them from our water supply. Unlike other works published to date that concentrate on issues of water supply, water resource management, hydrology, and water use by industry, this work is more tightly focused on the monitoring and improvement of the quality of existing water supplies and the recovery of wastewater via new and standard separation techniques Using analytical chemistry methods, offers remediation advice on pollutants and contaminants in addition to providing the critical identification perspective The players in the global boom of water purification are numerous and varied. Having worked extensively in academia and industry, the Editor-in-Chief has been careful about constructing a work for a shared audience and cause