CITY COUNCIL MEETING AGENDA PACKET

City of Pleasanton, CA (0012108.00) 2-1 Woodard & Curran, Inc. Pleasanton Long-Term Sewer CIP October 6, 2025 2. SEWER SYSTEM PROGRAM EVALUATIONS As part of the Sewer System Capacity and Condition Assessment, a condition assessment of the City’s gravity sewer network and sewer lift stations was conducted. These assessments determined the City’s near -term, mid-term, and long-term rehabilitation and replacement needs for each asset. A capacity analysis was also performed using the City’s hydraulic model of its sanitary sewer system, InfoWorks ICMTM. These findings identified pipes that were predicted to be undersized under both existing and future sewer flow scenarios. The following sections describe these assessments in more detail and present their findings. 2.1 Gravity Sewer Condition Assessment The City performs closed-circuit television (CCTV) inspections of its gravity mains up to 15 inches in diameter. The CCTV data was coded based on National Association of Sewer Services Companies (NASSCO) Pipeline Assessment Certification System (PACP) standards. As part of the condition assessment process, this inspection data is evaluated for the purposes of identifying CIP projects. The latest evaluation was completed in November 2024 by Woodard & Curran for pipes inspected and coded through June 2024. In total, 424,370 linear feet (or about 30 percent of the City-owned pipes in the gravity collection system) had CCTV data and defect scoring that could be utilized for a risk-based assessment. InfoAsset PlannerTM risk assessment software was used to develop likelihood of failure (LOF), consequence of failure (COF), and corresponding risk scores for each pipe in the system. LOF scoring was based on primarily structural condition information from the CCTV data and also included a “structural vulnerability” factor reflecting the age and material of the pipe (also used as a preliminary surrogate for structural condition for pipes without CCTV data), and frequency of required cleaning (“hot spots”) factor. COF scoring considered the pipe size (reflecting its potential flow volume), environmental consequence (e.g., proximity to storm drain inlets or Waters of the State), the type o f road type in which the sewer was located (reflecting the impact to the public and difficulty of repair), and community impact (proximity to commercial areas and public facilities). A risk-matrix weighting system was applied to each pipe’s LOF and COF score to determine an overall risk priority (very low, low, medium, or high) for each pipe. See Figure 2-1 for a map of risk priority for pipes in the system. In addition to the risk analysis, gravity sewers were assigned a rehabilitation and replacement (R&R) action based on an R&R decision process which analyzed pipes based on the quantity and types of structural defects present in the pipe. Based on this process, pipes with major defects (PACP grade 4 or 5 structural defects) are assigned a defect repair, full pipe lining, or pipe replacement R&R decision. Gravity sewers with no major defects were identified for continued preventive maintenance, and gravity sewers without CCTV data were assigned a CCTV priority. Based on the risk score and R&R decision for each gravity sewer pipe, recommendations for capital improvement projects were identified for inclusion i n the City’s long-term CIP. Page 220 of 323