Agmt19 Aecom Technical Services, Inc.

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Appendix 5: Utilities Evaluation Page 19 mitigation for each defect will be identified (up to 15 of these). Consultant will provide CCTV reports and inspections to the City in WinCan format, with MP4 video files and PACP exchange database. Task 3. City Data Reauirements: Wastewater flows for the Project area for existing and buildout conditions Task 4. Evaluate Stormwater System Consultant will perform a stormwater drainage system analysis to determine stormwater drainage system infrastructure requirements to serve the Project using the current models developed by the subconsultant. The current models include the "Eastern Low -Lying Area Drainage Master Plan" model (ELLA DMP) and the "ELLA Modification" basins. The proposed Project will increase the tributary area to the Redwood Creek channel. Therefore, the models will need to be combined to assess the impacts of the Project site to the Redwood Creek outfall. The combined model will reflect storm drain capacities necessary to meet City requirements; MS4 permit requirements will not be modeled but will be addressed in the report. The following work will be performed: • Combine the Hydraulic Models: Combine the City's existing stormwater drainage system hydraulic models to include the Project in one model. • Perform Hydraulic Evaluation of Existing and Proposed Storm Drain System: Perform a hydraulic analysis for the existing stormwater drainage system (existing development conditions) for a 10 -year, 30 -year and 100 -year storm. Add the proposed land use conditions and proposed drainage system and verify the proposed improvements for the 10 - year, 30 -year, and 100 -year storm events. Utilize hydraulic evaluation criteria developed in consultation with the City. • Perform Condition Assessment: Perform a condition assessment of the Redwood Creek outfall, the Beech, Cedar, and Chestnut siphons consisting of inspections at the outfall, and inspections at each end of the siphons. Document condition, sediment, trash, etc. of each in a technical memorandum with photos. • Identify Facility Impacts by Parcel: Allocate infrastructure capacity to the four parcels within the Specific Plan area using a methodology developed in consultation with the City. This information will be used in future evaluations by the City to determine impact fees associated with development of the Specific Plan area. Task 4. City Data Reauirements: Storm drainage as -built information for areas in or near the Project not already included in the City model. Task 5. Prepare Engineering Report Consultant will prepare an Engineering Report summarizing the hydraulic findings and conclusions including approximately 9 to 13 pages of text (one-page introduction, two- to three- page description for each system), and one to two exhibits per system, showing locations and diameters of existing and proposed facilities. Include maps comparing the capacity of each respective system for the pre -project condition, the post -project condition and the mitigated post - project condition, in order to ensure that there is no impact to the service performance of the various City utility systems. ATTY/AGR/2019/AMENDMENTS/AMEND NO.1-AECOM REV: 06-17-19 PR Page 19 of 22