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C. System Evaluation and Capacity Assurance Plan Evaluation—Sewer System Master Plan The City completed a Sewer System Master Plan in 2007 (Master Plan). The master planning effort evaluated the capacity of the existing sanitary sewer system assets and provided capacity design criteria for future assets. The study included a sanitary sewer and flow monitoring and inflow and infiltration (I&I) analysis.The study concluded that no basins or sub-basins exceeded 5% inflow/infiltration into their sewage basin. Furthermore, the study concluded that the City's collection system does not appear to have high levels of ground water infiltration. Two basins were identified as prioritized areas of concern when corrective action is needed. The City requires that redevelopment project proponents evaluate the offsite capacity impacts of their project through an engineering study. Evaluation-Hydraulic Model The City periodically monitors the flow in its sanitary sewer system to identify capacity deficiencies and to monitor the quantity of inflow and infiltration present. Overall, the City's collection system has adequate capacity to convey DWFs. Few deficiencies exist under dry weather flow conditions. Capacity deficiencies under WWF conditions represent less than 10 percent of the modeled collection system. The relatively few number of deficiencies can be attributed to a well-designed system without significant I/I problems. Design Criteria Section 13 of the City's Standard Specifications and details addresses requirements for materials and methods of installation for sanitary sewer mains(up to and including 15 inches(15") in diameter), laterals, manholes,and appurtenances within the City's sanitary sewer system. Capacity Enhancement Measures-Capital Improvement Program City staff selected to improve the collection system to convey the PWWFs of the 10-year 24-hour design storm.The pipe criteria set for this alternative was to pass the PWWFs while allowing the surcharge level to rise up to one foot below the manhole rim elevation. A number of pipelines require improvements to meet the City's surcharge criteria.The recommended CIP includes several pipeline improvements and capacity upgrades at several pump stations. Prioritizing the required capital improvements for the City sewer collection system is an important aspect of the CIP.The CIP needs to be phased in a manner that provides the City with an economical and realistic approach to implementing the CIP.The recommended improvements were separated into 15 projects. Schedule The schedule for the City's capacity enhancement projects is included in the City's Capital Improvement Program. 39IPage