65B - PROPOSED WATER AND SEWER RATE ADJ

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76 SEWER RATE STUDY I City of Santa Ana, CA CCTV Observations, Sewer Spills and Repairs The City has been performing CCTV inspections on about 70 miles of pipe each year. This equates to about a 6 -7 year cycle to cover the entire system. figure B 9 provides a map of sewer mains color coded by CCTV inspection year. The GIS database includes information compiled from CCTV inspections over the years. About 78 percent of the sewer system includes at least some inspection - related data. This information is very useful in that it provides the most accurate assessment of the facilities current (recent) condition and expectation for failure. The CCTV data also provides key indications related to ongoing operational / maintenance considerations. In general, the City has used these observations to identify sections of sewer to line or clean. However, it has not been used for risk assessment. Having the latest CCTV inspection results are critical in assessing current pipeline conditions. However, by comparing these results to prior inspections, one can also gain a better understanding of the rate of changes occurring. In some cases the presence of a pipe defect may not be much of an issue if it has been in the same condition for many years; perhaps even since construction. Over time, the City will be able to see trends in the deterioration of pipe to better project future replacement rates. Therefore, Black & Veatch strongly recommends the City implement a process for storing and assessing prior inspection data as well as the latest data set. The "Quick Structural Rating" (QSR) and "Quick Maintenance Rating' (QMR) values calculated based on the review of CCTV inspections are especially useful to this assessment study. Therefore, these factors have been addressed in their own sections below. Some of the CCTV observation data includes indications of pipeline problems, such as structural issues and grease or root issues. Of the structure issues listed, about 13 percent of all pipes in the collection system have at least one location that is broken, cracked, fractured, or has a hole or offset. Almost 29 percent of the pipe records are listed as having no structural defects. The remaining 58 percent had no structural issues value (not inspected or no recorded value). For grease, over 53 percent of all system lines are shown as being clean, about 29 percent have light grease, and only about 3 percent are listed at medium or heavy. The remaining 15 percent had no grease issue value. Roots show a similar status: 63 percent at none, 21 percent at light, and about 1 percent are listed at medium or heavy. The remaining 15 percent had no roots issue value. 65B -235 NOVEMBER 2014