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124 <br />SEWER RATE STUDY I City of Santa Ana, CA <br />REVISED ANALYSIS <br />At the request of the City, a revised Sewer System CIP Analysis was performed for Santa Ana after the <br />draft report was developed. The revised results reflect the removal of all OCSD -owned sewer mains. <br />None of the initial pipe statistics, cohorts, PoF / CoF criteria or prioritization factors were changed. The <br />non -City owned mains were removed after the full prioritization process to allow comparison of results. <br />The following sections provide the summarized results of the "revised" analysis starting at the <br />conclusion of the Business Risk Exposure (BRE) calculation. <br />Business Risk Exposure (BRE) <br />Figure D 1 provides a "heat map" graph showing the resulting distribution of PoF vs. CoF scores by miles <br />of City -owned mains. Combined, these represent the BRE score. Higher probability of failure assets are <br />plotted near the right. Higher consequences of failure assets are plotted near to the top. A partial table <br />of sewer main pipeline segments ranked by BRE score is included in the Replacement Prioritization <br />section below. <br />Figure D -1: Sewer System BRE Heat Map Graphic by Miles of City -Owned Sewer Mains <br />10 <br />OJ 9 <br />i <br />3 g <br />LA_ 7 <br />4- <br />O 6 <br />a <br />U <br />C 5 <br />GJ <br />O 4 <br />v <br />N 3 <br />C <br />O 2 <br />V <br />1 <br />Probability of Failure <br />1 2 3 4 5 6 7 <br />8 9 10 <br />0:2 <br />0.2 <br />2.3 <br />4.6 <br />0.3 <br />0.3 <br />0.4 <br />0.6 <br />1 0.2 <br />` 1.8 <br />2.7 <br />1.9 <br />14.3 <br />2.4 <br />2.5 <br />[ 2.9 <br />i 5.2 <br />2.4 <br />f 0.6 <br />0.3 1 0.4 <br />0.5 <br />3.2 <br />0.7 <br />( 0.6 <br />0.5 <br />1.1 <br />0.7 <br />0.3 <br />0.2 <br />0.4 <br />` 4.9 <br />C 1.1 <br />1.1 <br />1.1 <br />2.5 <br />0.2 <br />0.3 <br />0.8 <br />8.3 <br />1.5 <br />1.7 <br />f 1.9 <br />2.2 <br />1.5 <br />I 0.3 <br />0.2 0.3 <br />2.7 <br />28.4 <br />4.6 <br />4.5 <br />5.0 <br />` 6.0 <br />3.5 <br />( 1.2 <br />I 0.3 f 1.0 <br />10.2 <br />.9 <br />26.2 <br />19.0 <br />19.1 <br />31.3 <br />11.0 <br />5.5 <br />Total Miles: 397.2 <br />Inspection and Replacement Cost Calculation <br />Figure D 2 shows the distribution of BRE scores (across the bottom) against the total estimated <br />replacement costs for City -owned mains. The cumulative replacement cost line is also provided. <br />65B -283 <br />NOVEMBER 2014 <br />