Spring Valley is a census-designated place (CDP) in the East County region of San Diego County, California. The population was 28,205 at the 2010 census.
From 1970 through 1990, Spring Valley included what is now the La Presa CDP to the south; La Presa is still popularly considered to be a part of Spring Valley. Extended definitions of Spring Valley may also include the Casa de Oro neighborhood to the north, which belongs to the Casa de Oro-Mount Helix CDP. Locations in both La Presa and Casa de Oro use Spring Valley addresses.
Spring Valley is named for the natural spring located there. It was long the home of the Kumeyaay people, who called it Neti or Meti. Spanish conquerors drove off the natives and used the area for cattle, calling it El aguaje de San Jorge (St. George’s Spring).
In 1863 Judge Augustus S. Ensworth of San Diego filed a claim for a 160-acre (65 ha) ranch that included the spring. The ranch, and the small adobe house he built there, were sold to Rufus King Porter and later to historian Hubert Howe Bancroft. The adobe is now a National Historic Landmark.