Sewer Performance Reporting: Factors That Influence Blockages
Publication: Journal of Infrastructure Systems
Volume 17, Issue 1
Abstract
Managing sewer blockages represents a significant operational challenge for water utilities. In Australia, company-level blockage rates are used to compare the effectiveness of the management strategies of different utilities. Anecdotal evidence suggests that this basis may not be a fair one for comparison because blockages are influenced by a range of factors beyond management control and vary from company to company. This issue was investigated as part of a broader research effort on sewer-blockage management undertaken in conjunction with the Water Services Association of Australia (WSAA) and its members. A Web-based survey was used to collate expert opinion on factors that influence blockage rate. The identified factors were then investigated in an exploratory analysis of blockage-related data provided by two participating utilities, supported by literature reviews. The results indicate that blockage rate is influenced by a range of factors, including asset attributes, climatic conditions, water consumption, and soil type. Because these factors vary from utility to utility, this research supports the finding that company-level blockage rate in itself is not an appropriate metric for comparing management effectiveness.
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Acknowledgments
The writers would like to express their deep appreciation to all organizations and individuals who contributed to the WSAA-CSIRO collaborative project and to the development of this paper. The funding provided by WSAA and CSIRO’s Water for a Healthy Country National Flagship is also gratefully acknowledged, as is the internal (CSIRO) review of this paper by Steve Cook and Donavan Marney, and the helpful comments received from two anonymous external reviewers.
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Information & Authors
Information
Published In
Journal of Infrastructure Systems
Volume 17 • Issue 1 • March 2011
Pages: 42 - 51
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Dec 10, 2009
Accepted: Jul 28, 2010
Published online: Aug 2, 2010
Published in print: Mar 1, 2011
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