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City of San Leandro Sewer System Management Plan Volume I the system. The CCTV work is expected to help identify and verify causes of grease problems. Lines with known poor grade will be prioritized for CCTV inspection. With information on the causes of grease problems, maintenance activities and schedules can be modified or sewer repairs made to better control grease buildup and minimize grease-related SSOs. Section 8 -System Evaluation and Capacity Assurance Plan Introduction The City periodically conducts flow monitoring and hydraulic modeling analysis to anticipate future growth or increased demand on the system as well as to determine if excessive UI is impacting the capacity of the system. The nature of the demographics of the City is such that the City has not experienced growth or demand on the system that has necessitated updating the hydraulic capacity model since the last assessment in 1995. This is supported by the lack of SSO history and lack of evidence of any surcharging to indicate that assessments are required to evaluate the sanitary sewer system based on SSO discharges caused by hydraulic deficiency. The City is currently evaluating the timing of the next capacity assessment and flow monitoring program but expect to update it in the next three years. Capacity Assurance Program The capacity assurance process is used to determine estimated peak flows associated with wet weather conditions causing overflow events, estimates of the capacity of key system components, hydraulic deficiencies (including components of the system with limiting capacity) and the major sources that contribute to the peak flows associated with overflow events. The Sanitary Sewer Capability Study and Master Plan, completed in February 199 by Montgomery / Watson, is the last comprehensive study conducted and is used as the point of reference for the SSMP. The next program will assess capacity requirements and any associated capital improvements indicated in the next 1-5 years, 5-10 years, and 10--20 years. The City plans to update its plan as conditions indicate. The capacity of the City sanitary sewer system is analyzed using a computerized hydraulic model. The modeled portion of the system consists primarily of those sewers 10 inches in diameter and larger termed the trunk sewer system. The hydraulic model was used to simulate the flows in the system under existing and future peak flow conditions. The capacity of each modeled trunk sewer is compared to the peak design flow to determine if the existing sewers have adequate capacity to convey the projected flows. System Evaluation and Capacity Assurance The capacity assurance program is based on a capacity assessment that relates short term and long term capacity requirements to a capital improvement program for providing the hydraulic f~age X25