Livermore Valley, formerly Valle De San Jose, is a valley in eastern Alameda County, in the East Bay region of the San Francisco Bay Area, northern California. The valley is bounded by the Diablo Range on the north, east, and south; and is linked to the west with the Amador Valley. The city of Livermore is located in the valley. Watercourses draining the Livermore Valley include Arroyo Mocho, Arroyo Valle, Arroyo Seco, and Arroyo Las Positas.