Most of the water stored behind San Luis Dam is used for irrigation. The CVP share of the water is released down the Delta-Mendota Canal into the San Joaquin River, which provides water for of farmland in the central part of the San Joaquin Valley. Parts of the CVP and SWP water supply the Westlands Water District of Fresno and Kings Counties, which irrigates up to of land on the west side of the San Joaquin Valley. Prior to the construction of San Luis Dam and the joint use portion of the California Aqueduct (the San Luis Canal) this area depended entirely on groundwater. In 2016 the main crops grown here were almonds, tomatoes, pistachios and wheat. Most of the Westlands district consists of large corporate farms totaling hundreds if not thousands of acres. The SWP also provides more than of water per year for farmers in Kern County.