Using Water Main Break Data to Improve Asset Management for Small and Medium Utilities: District of Maple Ridge, B.C. Andrew Wood, Ph.D., P.E. 1 ; and Barbara J. Lence, Ph.D., A.M.ASCE 2 Abstract: An approach is developed for identifying key data to be used in asset management in general, and for predicting pipe breaks and selecting appropriate models in particular. The approach is applied to the District of Maple Ridge, B.C., Canada to identify the magnitude of a utility’s pipe burst problems today and in the future, enhance the development of pipe replacement priorities based on forecasted breaks, and identify key data to collect in future data acquisition programs. It may also be used by other utilities with varying amounts of data, and can be easily implemented with existing data management and analysis tools. DOI: 10.1061/ASCE1076-0342200915:2111 CE Database subject headings: Municipal water; Water distribution systems; Water pipelines; Rehabilitation; Canada. Introduction Water utilities have aging and deteriorating infrastructure and must prioritize the replacement of their water mains to minimize pipe breaks. Breaks result in loss of water to key businesses and critical facilities, may lead to damage of other infrastructure, and have been identified as a pathway for microbial contamination of distribution systems USEPA 2002. The need for rehabilitating aging water mains is increasing, the costs of repairs and replace- ment can be high, and the impact on customers potentially sig- nificant USEPA 2001. Asset management practices are generally used to prioritize pipe replacements and thereby identify invest- ment strategies that, on one hand, avoid premature replacement of pipes i.e., unnecessary preinvestment of funds, and on the other hand, avoid water main breaks, commensurate interruptions in service, and the costs of damage. An effective asset management decision is dependent on the ability to determine the future per- formance of water mains by predicting water main breaks, and identifying how such breaks may occur. Much research has focused on the development of models for predicting water main breaks and pipe deterioration, but the use of such models is not common among utilities. In addition, the amount and quality of water main break data available for devel- oping or implementing these models varies among utilities Wood and Lence 2006. Many utilities are not confident in the data they have and this is generally an impediment to investing in pipe prediction models. This paper reports on an approach applied to Maple Ridge, B.C. to identify key data to be used in asset management in gen- eral and pipe break prediction modeling in specific and to select the most appropriate model for predicting water main breaks. This information may then be used to enhance the development of replacement priorities based on forecasted breaks, the mainte- nance of the database, and the identification of future data acqui- sition programs. It provided the utility with a method for considering future pipe breaks in the analysis of pipe prioritiza- tion strategies, and it incorporates existing tools for data manage- ment and analysis that are widely available and easy to implement by small and medium size utilities. The approach is applicable to utilities with varying amounts of data. The results of the applica- tion of the work to the Laity View area of Maple Ridge, B.C. are reported in this paper. The following sections review the available techniques for predicting pipe breaks, the factors that influence break predictions, the approach employed for Maple Ridge to assist in asset management of its pipe networks and the results of the Maple Ridge implementation of the work. Water Main Breaks A number of authors analyze and report on the causes of breaks, including O’Day 1982, Marks et al. 1987, Male et al. 1990, Savic and Walters 1999, Rajani and Makar 2000, Rajani and Kleiner 2001, and Dingus et al. 2002. According to Rajani and Tesfamariam 2005, a combination of circumstances leads to pipe failure in most cases and different factors cause failure in different pipe networks. The causes of breaks include deteriora- tion as a result of use e.g., internal corrosion, physical loads applied to the pipe e.g., traffic, frost, limited structural resis- tance of the pipe because of construction practices during instal- lation and declining resistance over time e.g., corrosion, aging factors. Dingus et al. 2002 note multiple common failure modes for cast iron pipe systems and that corrosion, improper installation, and ground movement are the three most common causes of pipe failure. According to Levelton 2005, corrosion is dependent on a number of factors including material, soil type, chemical characteristics of soil, soil bacteria and stray electrical currents. Prediction Modeling of Water Main Breaks Break prediction models have been developed to help the water industry understand how pipes deteriorate and when pipes will 1 Municipal Engineer, District of Maple Ridge, 11995 Haney Place, Maple Ridge BC, Canada V2X 6A9. E-mail: awood@mapleridge.ca 2 Professor, Dept. of Civil Engineering, Univ. of British Columbia, 6250 Applied Science Lane, Vancouver BC, Canada V6T 1Z4. E-mail: lence@civil.ubc.ca Note. This manuscript was submitted on July 19, 2006; approved on March 31, 2008; published online on May 15, 2009. Discussion period open until November 1, 2009; separate discussions must be submitted for individual papers. This paper is part of the Journal of Infrastructure Systems, Vol. 15, No. 2, June 1, 2009. ©ASCE, ISSN 1076-0342/2009/ 2-111–119/$25.00. 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