Appendix I - Utilities and Service Systems Supporting Information COMBINED

June 2024 4 City of Pleasanton Tract 8569 (Ponderosa Homes) Hydraulic Analysis • Average Day Demand Evaluation: Under average day demands, the hydraulic model predicts the Project will experience service pressures of approximately 80 - 116 psi as documented on Figure 4. • Maximum Day Demand Evaluation: Under maximum day demands, the hydraulic model predicts the Project will experience service pressures of approximately 77 ~ 113 psi as documented on Figure 4. • Peak Hour Demand Evaluation: Under peak hour demands, the hydraulic model predicts the Project will experience service pressures of approximately 77 ~ 113 psi as documented on Figure 4. • Maximum Day Demand plus Fire Flow Evaluation: The fire flow analysis consisted of using the MDD in the hydraulic model and applying hypothetical fire flows. The analysis indicates that the proposed hydrant locations and pipelines can supply the 1,500-gpm fire flow requirement. The available fire flows at a pressure greater than 20 psi are documented on Figure 4. • Pipeline Velocities: The maximum pipeline velocities predicted during peak hour demands are also documented on Figure 4. The proposed 8-inch mains are under the pipeline criteria of 10 fps during PHDs with a maximum velocity of approximately 0.1 fps. The connection to the Moller 770 Pressure Zone will require approximately 2,450 feet of 10-inch pipeline in the Laurel Creek Emergency Vehicle Access Road connecting to the existing 12-inch main in Crosby Drive to supply the project. Due to the steep terrain and potential for soil creep, it is recommended that a fully restrained pipeline be utilized. 5.0 STORAGE AND PUMPING INFRASTRUCTURE IMPACTS The total required storage criteria includes provisions for Operation (25% of MDD), Emergency (50% of MDD), and Fire Flow. The required storage for Tract 8569 is summarized as follows: Project Required Storage: o Operational Storage: 0.006 MG o Emergency Storage: 0.011 MG o Fire Flow Storage: 0.18 MG o Total Storage Impacts: 0.20 MG Alternative 1 and 2 – Dublin Canyon Storage Impacts: The current fire flow storage requirement in the Dublin Canyon Pressure Zone is 0.42 MG (3,500 gpm x 2 hrs), which is larger than the Tract 8569 requirement, therefore no additional fire storage is required for the Project resulting with a total storage requirement of 0.017 MG. The Dublin Canyon