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City of Santa Ana, CA WATER RATE STUDY <br />INTRODUCTION <br />Making informed decisions to maximize the integrity of a utility's infrastructure in today's economic and <br />business environment can be a challenging task. In many cases, a utility's greatest ally is existing <br />information about their infrastructure. By tapping into existing datasets and staff knowledge, critical <br />information can gleaned about the condition and life expectancies of their facilities; and these can be <br />related to ever - changing business drivers, operational strategies, and budgetary priorities. <br />Capital improvement planning (CIP) for the outside plant assets can also be a challenge. In many cases <br />direct visual inspection of the assets may not be possible or economically feasible. Therefore, condition <br />assessments must rely mostly on existing information and indirect assessments. The process typically <br />evaluates a variety of information such as pipe materials, main break rates, installation dates, soil <br />conditions, proximity to sensitive customers, hydraulic model results, etc. In many cases the most <br />accessible and usable data is from the utility's Geographic Information System (GIS) and /or asset <br />management database(s). This data is used to assist in prioritizing facilities for inspections and /or <br />renewal based on criticality, life- expectancy, and /or geographic boundaries (e.g. City Council <br />boundaries). <br />CIP FOR OUTSIDE PLANT ASSETS <br />The general approach to capital improvement planning for the outside plant assets typically follows a <br />multi- stepped process. For the City's pipeline assessment, a set of GIS -based tools and processes were <br />used. Combined, these are called "iCIP" for interactive Capital Improvement Planning. The typical steps <br />include: <br />1. Compile source data for the assets to be evaluated in the study. This often includes the utility's <br />GIS and /or asset management database(s), a variety of spreadsheets, and input from the <br />utility's staff. <br />2. Review source data to gain an overall understanding of the quantity and quality of the data. <br />Special attention is given to missing or conflicting information. This data is also evaluated to <br />determine which sources are suitable for CIP assessment and which data appear to provide <br />insight into the past, current or future condition of the assets. <br />3. Organize source data into a logical data structure suitable for further analysis. <br />4. Perform both spatial and non - spatial assessments to identify statistically- significant trends. <br />Much of this is considered "exploratory" as relationships between things like pipe material, <br />break frequencies, and soil conditions are often not readily apparent. In many cases only a <br />cursory review of these relationships can be performed due to time and budget constraints, or <br />lack of sufficient source data. <br />5. Identify key Probability of Failure (PoF) criteria based on the initial review of source data. PoF is <br />also known as Likelihood of Failure (LoF). These typically include such factors as: <br />a. Main breaks <br />b. Customer Complaints <br />c. Soil Conditions <br />d. Pipe Diameter and Material <br />e. Pipe Age / Remaining Life <br />f. Pipe Inspections/ Condition <br />BLACK & VEATCH I Appendix B: Water CIP Prioritization P, a:. e,. <br />M \• M • <br />• • <br />77 <br />