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<br />Consulting Services Agreement between <br />City of San Leandro and RMC Water and Environment—Exhibit A Page 5 of 9 <br />Task 4 Deliverables: <br /> Calibrated hydraulic model for the sewer system (model files plus data exported to GIS and/or <br />Excel tables) <br /> <br />Task 4 Assumptions: <br /> RMC will use its own model licenses for the work under this project <br /> City staff will provide record drawings and assistance with field verification if needed to obtain or <br />confirm data for critical sewers included within the model <br /> <br />Task 4 Schedule: <br /> Model shall be delivered at time of submittal of final deliverables under Task 9 <br /> <br />Task 5 – System Performance Evaluation and Improvement Needs <br />This task involves evaluation of collection system capacity and identification of specific improvement needs <br />to address any deficiencies. <br /> <br />Subtask 5.1 Establish Capacity Evaluation and Design Criteria and Level of Service <br />RMC will propose appropriate design and hydraulic criteria to be used for assessing the capacity of existing <br />sewer facilities and sizing new facilities, including Manning’s “n” factor for gravity sewers or Hazen-Williams <br />“C” for force mains, maximum d/D values, minimum and maximum velocities, slopes, and depth of cover, <br />and pump station design and reliability considerations (e.g., firm capacity). RMC will also identify <br />alternative approaches for defining an appropriate design storm or storms, including use of an actual <br />historical storm or a synthetic event based on rainfall intensity-duration-frequency statistics or other <br />methods such as the SCS Type IA distribution curve. RMC will propose criteria for evaluating the <br />performance of the system under the design event (e.g., acceptable level of surcharge) that reflects the <br />City’s desired level of service and risk acceptance. The proposed criteria will be reviewed and discussed <br />with City staff. <br /> <br />Subtask 5.2 Evaluate Existing System Performance <br />Using the hydraulic model and based on the criteria established in Subtask 5.1, RMC will evaluate the <br />performance of the existing gravity trunk sewers, pump stations, and force mains under existing and future <br />dry and design wet weather flows. Capacity deficiencies will be identified based on the perfo rmance criteria <br />established in Subtask 5.1. Thematic maps and hydraulic grade line plots will be prepared to present the <br />identified capacity problem areas. <br /> <br />Subtask 5.3 Develop Capacity Improvement Projects <br />This subtask includes the following activities: <br /> Development of Alternatives and Preliminary Solutions. Using an iterative simulation process and <br />engineering judgment, RMC will develop and test solutions to identified capacity deficiencies. <br />Solutions may include upsizing or paralleling existing pipes, upgrading pump stations that lack <br />sufficient firm capacity, consolidating flows in new sewers or existing sewers with available <br />capacity, implementing flow diversions at critical locations, or sewer rehabilitation to reduce I/I. <br />Based on preliminary model results and discussion with City staff, the alternatives will be refined <br />and focused on the most viable solutions for more detailed project development. <br /> Analysis of Proposed Solutions. RMC will evaluate potential project alternatives in further detail, <br />including review of projects sites on aerial mapping or in the field. The purpose of these