West False River Drought Salinity Barrier Project Environmental Impact Report (Draft)

The California Department of Water Resources (DWR) proposes to the install the West False River Drought Salinity Barrier Project (proposed project). During drought conditions, water stored in upstream reservoirs may be insufficient to repel salinity moving upstream from San Francisco Bay. Without the protection of the drought salinity barrier in West False River, saltwater intrusions could affect more than 27 million Californians who rely on the Sacramento–San Joaquin Delta (Delta) for at least a portion of their water supply; could render Delta water unusable for agricultural needs; and could reduce the value of habitat for aquatic species. DWR installed emergency drought barriers in West False River in 2015 and 2021–2022 in response to drought conditions to protect water quality in the interior Delta. Installation of a drought salinity barrier in West False River has been shown to be an effective tool for reducing the intrusion of saltwater into the Central and South Delta based on these previous installations (see Section 1.2, “Project Background,” in Chapter 1; California Department of Water Resources 2019).