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City of Santa Ana, CA I SEWER RATE STUDY <br />The National Association of Sewer Service Companies ( NASSCO) has developed a standardized system of <br />ratings to provide a consistent assessment of sanitary sewer conditions. Known as the Pipeline <br />Assessment Condition Program (PACP), the system provides the capability to benchmark sewer <br />conditions in order track deterioration over time. Using the PACP process allows utilities to identify <br />major deterioration factors and assign a rating reflecting the likelihood of collapse. CCTV data only <br />provides information on the internal defects that affect condition. Utilities need additional information <br />to fully assess the condition of a main. The PACP process classifies deterioration factors in "structural' <br />defects and "O &M" defects. Ratings are based on a 5 -point system with 1 being "excellent condition — <br />minor defects" and 5 being "immediate action — pipe will likely fail in less than 5 years." Table 6 <br />summarizes the NASCCO PACP Rating system. <br />Table 6: NASCCO PACP Rating System <br />1 <br />Excellent <br />Minor defects <br />Defects that have <br />2 <br />not started <br />Good <br />deteriorating <br />Moderate defects <br />3 <br />that will continue to <br />Fair <br />deteriorate <br />4 <br />Poor <br />Severe defects <br />5 <br />Immediate <br />Defect requires <br />Attention <br />immediate action <br />Unlikely in the <br />foreseeable future No cracks <br />Unlikely to fail for at Some longitudinal <br />least 20 years cracking visible <br />May fail in 30 to 20 <br />years <br />Probably will fail in <br />5 to 10 years <br />Has failed or likely <br />will fail within the <br />next 5 years <br />Multiple fractures <br />Broken pipe <br />Collapsed pipe <br />Free of roots and <br />deposits <br />Fine roots present <br />Capacity decrease of up <br />to 15 percent due to <br />deposits <br />Infiltration occurring <br />Root ball decreasing <br />flow capacity by up to <br />50 percent <br />Figures 2 and 3 present the CCTV for the City's sewer system using the "Quick Structural Rating" (QSR) <br />and "Quick Maintenance Rating" (QMR) values calculated based on the rating process in Table 6. Black & <br />Veatch notes that while QMR ratings provide useful information regarding maintenance practices, Black <br />& Veatch did not use them as part of the prioritization process. Operational and local FOG (fats, oils and <br />grease) issues rather than installation materials, structural conditions or probability of failure <br />considerations, impact QMR scores more. <br />BLACK & VEATCH I Sewer Rate Study <br />65B -186 <br />VIVA <br />