The aqueduct begins at the Sacramento–San Joaquin River Delta at the Banks Pumping Plant, which pumps from the Clifton Court Forebay. Water is pumped by the Banks Pumping Plant to the Bethany Reservoir, which serves as a forebay for the South Bay Aqueduct via the South Bay Pumping Plant. From the Bethany Reservoir, the aqueduct flows by gravity approximately to the O'Neill Forebay at the San Luis Reservoir. From the O'Neill Forebay, it flows approximately to the Dos Amigos Pumping Plant. After Dos Amigos, the aqueduct flows about to where the Coastal Branch splits from the "main line". The split is approximately south-southeast of Kettleman City. After the Coastal Branch, the line continues by gravity another to the Buena Vista Pumping Plant. From the Buena Vista, it flows approximately to the Teerink Pumping Plant. After Teerink it flows about to the Chrisman Pumping Plant. Chrisman is the last pumping plant before the Edmonston Pumping Plant, which is from Chrisman. South of the plant the west branch splits off in a southwesterly direction to serve the Los Angeles Basin. At the Edmonston Pumping Plant it is pumped over the Tehachapi Mountains.