Stochastic Evaluation of Reservoir Operation Rules

The major water facilities in California encompass the State Water Project, operated by the State of California, and the Central Valley Project, owned and operated by the United States through the Bureau of Reclamation. The principal impounding facilities (dams and reservoirs) of these systems lie in the northern part of the State (Sacramento Valley), where most of the State's runoff occurs. The historical hydrology presently used for operational planning covers 1922-1978, a span of 57 years. In light of the complexity of these water systems, and at the same time, the lack of variety in extreme events, this span of hydrology is considered insufficient to measure the probabilities of system performance, especially during droughts. Accordingly, three-hundred 57-year-long sequences (17,100 years) of Sacramento Valley hydrology have been generated synthetically by applying a stochastic hydrology model based on W.L. Lane's Applied Stochastic Techniques (LAST). Two sets of operational rules for the State Water Project are evaluated using the generated hydrology.