Correcting Power Leakage Equation for Improved Leakage Modeling and Detection
Publication: Journal of Water Resources Planning and Management
Volume 146, Issue 3
Abstract
Fluid pressure influences leakage flow rate in water distribution pipe networks. Significant progress has been made in the use of pressure management techniques to control leakage. An empirical power equation (known as the power equation) is widely used to model the pressure–leakage relationship in practice. However, recent research has shown that this equation is not able to accurately model leakage under various conditions. When estimating the N1 leakage exponent for a system, the power equation assumes that leakage is located at a point in the network that is representative of the average system pressure, which is rarely true. In addition, parameters of the power equation are not constant but vary with pressure, which is a problem especially for water distribution pipe networks where pressure varies with time, for example, due to diurnal demand variation. These factors result in significant errors when the power equation is used to model leakage in real water distribution networks. This technical note analyzes the factors that introduce errors in the power equation and proposes methods to improve its accuracy. The performance of the methods is demonstrated using a case study.
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Acknowledgments
The authors would like to express their appreciation to Mr. Simon Scruton and his team at the eThekwini Water and Sanitation unit for providing the water distribution network model of the central business district of Durban.
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Published In
Journal of Water Resources Planning and Management
Volume 146 • Issue 3 • March 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: Jul 6, 2018
Accepted: Aug 15, 2019
Published online: Jan 10, 2020
Published in print: Mar 1, 2020
Discussion open until: Jun 10, 2020
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