Water Supply Scarcity in Southern California: Assessing Water District Level Strategies

Abstract

Urban water scarcity is an ongoing reality in California, especially, in Southern California with its arid climate and cyclical droughts. Southern California relies on upstate water imports provided by the Metropolitan Water District of Southern California (MWD) for a significant portion of its water supply. MWD also imports water from the Colorado River, conveyed through the Colorado River Aqueduct. Key to the transportation of water from the mountains in Northern California to the south is the Sacramento-San Joaquin River Delta, vulnerable to aging levees, subsidence and saltwater intrusion. In addition, the environmental deterioration of the Sacramento-San Joaquin River Delta, habitat to several endangered species, has led to ongoing restrictions on MWD water deliveries to Southern California water agencies. This has renewed efforts to both provide for the environmental improvement of the Delta ecosystem, as well as to find a solution for water conveyance, either through a canal, or more recently, through twin tunnels. In addition, the susceptibility of the Sacramento-San Joaquin River Delta to a major Bay Area earthquake increases the threat of disruption of water imports for Southern California.