Energy Metrics for Water Distribution System Assessment: Case Study of the Toronto Network
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VIEW THE REPLYPublication: Journal of Water Resources Planning and Management
Volume 141, Issue 11
Abstract
Descriptive energy metrics, calculated for each component, represent how the hydraulic state of a network evolves and how energy flows vary temporally and spatially. More specifically, these metrics describe how the energy supplied is partitioned between the energy that is dissipated, lost, and delivered throughout the system. The metrics are meant to support planning, from local (e.g., pump or pipe renewal) to system-wide (e.g., leakage or pressure management) decisions. Whereas aggregate results are indicators of system capacity, efficiency, greenhouse gas emissions, and costs, the comparison of component metrics allows for the identification of specific pipes, tanks, or pumps for which changes would be most beneficial. Furthermore, analysis of the temporal variation of energy flows facilitates the assessment of operation under multiple scenarios. The metrics are applied to a case study of the Toronto water distribution system and show, based on two scenarios provided by Toronto Water, that on average, less than 27% of the energy supplied is actually delivered to users. This system inefficiency has important economic and environmental repercussions. Nevertheless, changes to operations, such as improved pump maintenance or scheduling, have significant potential to lower costs and exploit lower greenhouse gas emission factors.
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Acknowledgments
This paper is partly based on case study research conducted within the project “Integrated Water Mapping: Enhancing Decision Support for Sustainable Water Planning with Municipal Data,” by Cities Centre and the Canadian Urban Institute, and funded by the Ontario Ministry of Environment through the Showcasing Water Innovation program. However, the findings, interpretations, and conclusions in this document are entirely those of the authors, and should not be attributed to the aforementioned organizations. The authors acknowledge the inputs of Katelyn Margerm, Kathryn Grond, Tom Weatherburn, Jeff Evenson, and the Toronto Water staff.
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Information & Authors
Information
Published In
Journal of Water Resources Planning and Management
Volume 141 • Issue 11 • November 2015
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Nov 5, 2014
Accepted: Apr 14, 2015
Published online: Jun 10, 2015
Published in print: Nov 1, 2015
Discussion open until: Nov 10, 2015
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