Charter Oak is an unincorporated community and census-designated place (CDP) in the San Gabriel Valley of Los Angeles County, California, approximately east of downtown Los Angeles. The population was 9,739 at the 2020 census, up from 9,310 at the 2010 census.
Charter Oak is located in the eastern San Gabriel Valley, situated along Arrow Highway in between Covina to the south, Glendora to the north and San Dimas to the east. Residents tend to refer to the CDP portion as the "unincorporated part of Covina", or simply as "Covina".
Originally a small agricultural settlement (primarily citrus orchards) centered on the intersection of Arrow Highway and Bonnie Cove Avenue, population growth greatly expanded the area recognized as "Charter Oak". In the 1960s, it evolved into a "bedroom community" suburb of Los Angeles and commercial agriculture is nearly gone.
Today, the generally accepted boundaries of historical Charter Oak are I-210 to the north, Valley Center Avenue to the east, Covina Hills Road to the south and Grand Avenue to the west, corresponding to the boundaries of Charter Oak Unified School District. However, the actual CDP area is notably smaller in the present day. This places a large part of the area historically and colloquially known as Charter Oak within the modern-day city limits of Covina and Glendora.
Geography
Charter Oak is located at (34.101308, -117.857656).
Charter Oak is primarily flat ground, though the South Hills of Glendora form much of the northern border, and there is a small valley in the southeast quadrant, with Walnut Creek flowing in the bottom. The other major water feature in Charter Oak is the San Dimas Wash, a concrete-lined flood control channel which was formerly the San Dimas River, a tributary of the San Gabriel River. Both Walnut Creek and San Dimas wash flow from east-northeast toward west-southwest, the wash in Glendora and the creek in Covina.
The ground is described as "dry riverbed," with sandy soil which was suitable not only for the citrus orchards which once were the primary industry in the area, but also for several nurseries growing cactus and other small plants.
According to the United States Census Bureau, the CDP has a total area of , all of it land.
History of Charter Oak
Early inhabitants and Rancho era (Pre-1880s)
The area that became Charter Oak was originally inhabited by the Tongva (Gabrielino) people, who had lived in the San Gabriel Valley for thousands of years before European contact. During the Spanish and Mexican periods, this region was part of expansive land grants known as ranchos, notably Rancho La Puente (granted to John A. Rowland and William Workman in 1842) and Rancho Azusa de Dalton (acquired by Englishman Henry Dalton in 1844). Following the Mexican-American War and the incorporation of California into the United States, these large ranchos were gradually subdivided, paving the way for American settlers and agriculture in the late 19th century.
Origin of "Charter Oak" name and early settlement
Following the Mexican–American War and California's transition to American rule, the area attracted settlers due to its fertile land and water availability. The community of Charter Oak emerged during the 1850s, primarily focusing on agriculture, particularly citrus cultivation. The area was named after a large oak tree which stood prominently and became a local landmark.
There are two versions of how Charter Oak received its name. According to the historically documented account, American soldiers camped in the area during the Mexican–American War associated the large oak tree with Connecticut's famous Charter Oak, where colonists once hid their charter from English authorities, hence giving the tree its name.
Charter Oak School and community growth
In 1894, residents established the Charter Oak School District to provide local education for the area's growing population. Initially operating from a single-room tent, the school soon expanded into a permanent wooden structure and later into a larger, mission-style building in 1922. This institution became a defining element of the Charter Oak community identity.
Postwar suburbanization and annexations
Following World War II, Charter Oak transitioned rapidly from a rural, agricultural community into a suburban neighborhood, as citrus orchards gave way to residential subdivisions. Portions of Charter Oak were annexed by neighboring cities Covina (areas south of Arrow Highway) and Glendora (areas north of Arrow Highway), significantly reducing the size of the unincorporated area.
Education and culture
Most of the census-designated place is served by the Charter Oak Unified School District,<!--UNI 08190--> while a portion is in Covina-Valley Unified School District<!--UNI 10050--> The boundaries of the Charter Oak Unified School District, formed in areas which were at the time unincorporated area, eventually became the accepted boundaries of historical Charter Oak, attesting to the importance of the district in the community. There are also private schools in the area.
Community college students from Charter Oak generally attend Citrus College in Glendora or Mount San Antonio College ("Mount SAC") in Walnut.
Charter Oak Gymnastics has been a U.S. National Team training center since 1989, and has produced many elite athletes, including national champion Vanessa Atler and Olympian Jamie Dantzscher.