2025 Urban Water Management Plan

Section 3 2025 Urban Water Management Plan Service Area Description City of Pleasanton Public Draft | May 2026 3-10 EKI Environment & Water, Inc. 3.5 Water Distribution System Pleasanton operates separate potable and non-potable water distribution systems. Sections 3.5.1 and 3.5.2 describe the facilities and components of the two separate systems. The non-potable system supplies recycled water treated at DSRSD’s Regional Wastewater Treatment Facility (RWTF). Pleasanton’s supply portfolio also includes recycled water, which the City receives from Livermore and through the San Ramon Valley Recycled Water Program (SRVRWP), which is operated by DERWA. 3.5.1 Potable Water Distribution System Until 2023, Pleasanton purchased about 75% of its potable supply from Zone 7 in the form of treated water. The remainder was met through groundwater pumped from local wells owned and operated by the City. Water from the City’s wells was treated with chlorine, ammonia, and fluoride prior to entering the water distribution system. However, due to contamination risk from per- and polyfluoroalkyl substances (PFAS), the City chose to stop operating its groundwater wells in 2023. Pleasanton plans to reintroduce groundwater as a source for its system; more detail on groundwater supply is provided in Section 6.2. Since 2023, Zone 7 has supplied all of the City’s potable water. Supply from Zone 7 enters Pleasanton’s water system at seven different turnout locations, as follows: • Turnout 1 is located on Santa Rita Road near Stoneridge Drive • Turnout 2 is located on Hopyard Road near Valley Trails Drive • Turnout 3 is located at the east end of West Las Positas Boulevard near Gulfstream Street • Turnout 4 is located on Hopyard Road at Stoneridge Drive • Turnout 5 is located on Bernal Avenue at Nevada Street • Turnout 6 is located on Machado Drive at Vineyard Avenue • Turnout 7 is located on Vineyard Avenue at Ruby Hills Boulevard All turnouts are equipped with facilities to fluoridate supply prior to introducing it into Pleasanton’s potable water system. Turnouts 1, 2, 3, 4, and 5 directly supply the system, with Turnouts 3-5 serving the majority, and turnouts 6 and 7 connect to the Vineyard and Ruby Hills water pump stations, which pressurize the system. Pleasanton’s potable system currently consists of approximately 340 miles of pipelines and 22,370 water service connections. The system has 12 pump stations, 20 water storage reservoirs, and one hydropneumatic tank. The service area has 16 different pressure zones. Pressuring reducing valves and pump stations help to maintain appropriate pressures within each zone. Pleasanton has emergency interties to connect the potable system with those of neighboring water suppliers, including two interties with DSRSD and one with Livermore. These interties are strictly for emergency conditions, such as a major pipeline break, supply contamination, or water service interruption that may be caused by earthquakes, floods, or other disasters. In preparing the 2024 WDSCMP, the City recently evaluated the potable distribution system’s current condition and its capacity to meet future water demands. While the evaluation concluded that capacity in much of the system is adequate to meet anticipated future demands, several improvements were recommended, including: increasing local storage, updating and upsizing aging water mains, and increasing looped connectivity within the system to enhance pressure distribution (Pleasanton, 2024). Figure 3-6 identifies key aspects of the City’s potable distribution system and its 16 pressure zones, as identified in the 2024 WDSCMP.