The updated plans for the Bay Delta Conservation Plan (BDCP) and a range of alternative proposals will undergo a rigorous public environmental review in the coming months.
The final costs of building the new facilities will be determined through detailed engineering and environmental studies, but are put at about US$14bn.
Officials emphasized that California’s water system is unsustainable from an environmental and economic perspective, and that the BDCP is a key part of a comprehensive solution to achieve the dual goals of a reliable water supply for California and a healthy ecosystem.
Population growth, habitat loss and ongoing threats to levee stability and water supply have crippled the California Bay Delta, threatening the health and economies of California communities, they warned. "A healthy Delta ecosystem and a reliable water supply are profoundly important to California's future," said governor Jerry Brown. "This proposal balances the concerns of those who live and work in the Delta, those who rely on it for water and those who appreciate its beauty, fish, waterfowl and wildlife."
The elements of a preferred proposal include the construction of water intake facilities with a total capacity of 9,000 cubic feet per second (cfs) and a conveyance designed to use gravity flow to maximize energy efficiency and to minimize environmental impact. Other alternatives, including no conveyance facility, and facilities with capacities ranging from 3,000 to 15,000 cfs, will also be considered as part of the upcoming environmental review process.