2025 Urban Water Management Plan

2025 Urban Water Management Plan Executive Summary City of Pleasanton Public Draft | May 2026 ES-3 EKI Environment & Water, Inc. will give the City the ability to once again access its full groundwater pumping quota (GPQ). Zone 7’s supplies are made up of 80% imported water from the State Water Project, and the remainder comes from groundwater and local surface water. The future reliability of Zone 7’s imported water is a concern. drought, sea level rise, and natural disasters threaten the Sacramento-San Joaquin Delta (Delta), a critical component of the delivery system bringing water to Zone 7. As a result, Zone 7 is participating in various projects that would provide alternate water supplies or protect the existing delivery system against threats. These projects include installing a pipeline system beneath the Delta , reusing highly treated wastewater, and participating in the construction of a new reservoir to store surplus water in wet years. Based on Zone 7’s efforts and the City’s continued use of groundwater, the City’s future water supplies are expected to keep pace with its water demands. Conservation Target Compliance In 2020, the City achieved its 20% reduction target in accordance with SB X7-7. This achievement was the result of continued water conservation by its customers following the 2014-2016 drought, in addition to using recycled water for irrigation in place of potable water. City Water Service Reliability The California Water Code asks agencies to evaluate their water service reliability by examining the impact of drought on their water supplies and comparing those reduced supplies to water demands. Specifically, agencies should calculate their water supplies during a single dry year and five consecutive dry years using historical records. For example, the City can estimate its supply during a single dry year by looking at how much supply was available during the driest year on record. If that historical “dry year” amount was reduced by 10%, then the City can conservatively assume a similar 10% reduction in supplies in a future dry year. The City is well-positioned to withstand the effects of a single dry year and a five-year drought. The City’s drought risk was specifically assessed between 2026 and 2030, assuming that the next five years are dry years. Based on Zone 7’s ability to meet all its water demands during dry conditions, the City is expected to have enough water supplies to meet water demands for a five-year drought beginning in 2026. This remains true for five-year droughts beginning in 2030, 2035, and 2040. However, in the fifth year of a drought starting in 2045, Zone 7 predicts a 14% supply shortfall to all of its retailers including the City. The City’s ability to supply its own groundwater and recycled water buffer that shortfall and the City projects a 10% supply shortfall in that scenario. With the implementation of its Water Shortage Contingency Plan (WSCP), the City can implement sufficient temporary water conservation to completely reduce the shortfall. Water Shortage Contingency Plan A WSCP describes an agency’s plan for preparing for and responding to water shortages. The City updated its WSCP to include its process for assessing potential gaps between planned water supply and demands for the current year and the next potentially dry year. The City previously aligned its water shortage levels with the State for consistent messaging and planned for locally appropriate water shortage responses. The WSCP may be used for foreseeable and unforeseeable events and is adopted concurrently with this UWMP by separate resolution to allow for updates as conditions change.