Diamond Bar is a city in easternLos Angeles County,California, United States.[7] The2020 census listed a population of 55,072.[8] It is one of a fewcities in California with a majority Asian population (59.24% as of 2020).[9] It is named after the "diamond over a bar" branding iron registered in 1918 by ranch owner Frederic E. Lewis (1884–1963). The city features a public Los Angeles County golf course.
Northern Diamond Bar is a part of the Pomona Unified School District.[11] Southern Diamond Bar is a part of the Walnut Valley Unified School District.[12] The city is also served by International Polytechnic High School.[13] It also has the firsthydrogen fueling station to be built in Southern California,[14] near theSouth Coast Air Quality Management District building.
In 1840, José de la Luz Linares received the 4,340-acre (1,760 ha)Mexican land grantRancho Los Nogales (Ranch of the Walnut Trees) from GovernorJuan Alvarado. The land grant included Brea Canyon and the easternWalnut Valley. Linares died in 1847, and his widow sold a part of the ranch toRicardo Vejar for $100 in merchandise, 100 calves, and the assumption of her late husband's debts. Vejar also owned theRancho San Jose to the east, and acquired the rest of Rancho Nogales over the next 10 years.[15]
However, Vejar's luck did not last that long. As time wore on – and particularly as the United States government took over California – Rancho Los Nogales was divided and sold into multiple land ranches, the largest of which was the Diamond Bar Ranch. At the time, it was one of the largest working cattle ranches in the western U.S. The entire Diamond Bar Ranch was acquired by theTransamerica Corporation in the 1950s for the purpose of developing one of the nation's first master-planned communities. Transamerica gave the Diamond Bar name to its new community and incorporated the ranch's familiar diamond and bar cattle brand into various logos (many of which are still in use today).[16]
The first houses in this development were built in 1959, adjacent to the future location of thePomona Freeway, which was built through the area ten years later. The town's development and population grew extremely quickly after that.
Transamerica oversaw all development of the community through the 1960s. The Transamerica Corporation divested itself of all its real estate ventures in the 1970s and 1980s. As a result, the Diamond Bar project was sold to multiple developers and much of its initial master plan was not implemented during the latter half of its development in the 1980s.
The City of Diamond Bar was incorporated on April 18, 1989.
Diamond Bar's main road, Diamond Bar Boulevard, runs along the bottom of the valley that eventually becomesBrea Canyon, and housing developments overlook the boulevard on both sides from surrounding hills. The city lies roughly between the ends of theChino Fault and theWhittier Fault, both part of theElsinore Fault Zone.
According to theUnited States Census Bureau, the city has a total area of 14.9 square miles (39 km2), with no significant bodies of water.
Boththe CA-60 Freeway andthe CA-57 Freeway run through Diamond Bar.the I-10 Freeway is just north of the city andCA-71 is just east of the city. Major thoroughfares include Grand Avenue, Diamond Bar Boulevard, Pathfinder Road, Golden Springs Drive, and Brea Canyon Road.
Diamond Bar city, California – Racial and ethnic composition Note: the US Census treats Hispanic/Latino as an ethnic category. This table excludes Latinos from the racial categories and assigns them to a separate category. Hispanics/Latinos may be of any race.
The census reported that 99.6% of the population lived in households, 0.3% lived in non-institutionalized group quarters, and 0.1% were institutionalized.[36]
There were 18,173 households, out of which 33.7% included children under the age of 18, 61.7% were married-couple households, 3.3% werecohabiting couple households, 22.3% had a female householder with no partner present, and 12.7% had a male householder with no partner present. 13.8% of households were one person, and 6.5% were one person aged 65 or older. The average household size was 3.02.[36] There were 14,846families (81.7% of all households).[37]
The age distribution was 18.4% under the age of 18, 9.0% aged 18 to 24, 24.1% aged 25 to 44, 29.6% aged 45 to 64, and 18.9% who were 65years of age or older. The median age was 43.8years. For every 100 females, there were 94.5 males.[36]
There were 18,819 housing units at an average density of 1,265.6 units per square mile (488.7 units/km2), of which 18,173 (96.6%) were occupied. Of these, 74.2% were owner-occupied, and 25.8% were occupied by renters.[36]
The median household income in 2023 was $106,602, with 9.1% of the population living below the poverty line.[38]
The2010 United States census[39] reported that Diamond Bar had a population of 55,544. The population density was 3,731.5 inhabitants per square mile (1,440.7/km2). The racial makeup of Diamond Bar was: 29,144 (52.5%)Asian; 18,434 (33.2%)White (21.3% Non-Hispanic White),[40] 2,288 (4.1%)African American; 178 (0.3%)Native American; 106 (0.2%)Pacific Islander; 3,237 (5.8%) fromother races; and 2,157 (3.9%) from two or more races. There were 11,138 residents ofHispanic orLatino origin, of any race (20.1%).
The Census reported that 55,415 people (99.8% of the population) lived in households, 102 (0.2%) lived in non-institutionalized group quarters, and 27 (0%) were institutionalized.
There were 17,880 households, out of which 7,008 (39.2%) had children under the age of 18 living in them, 11,792 (66.0%) wereopposite-sex married couples living together, 2,165 (12.1%) had a female householder with no husband present, 886 (5.0%) had a male householder with no wife present. There were 496 (2.8%)unmarried opposite-sex partnerships, and 71 (0.4%)same-sex married couples or partnerships. 2,308 households (12.9%) were made up of individuals, and 740 (4.1%) had someone living alone who was 65 years of age or older. The average household size was 3.10. There were 14,843families (83.0% of all households); the average family size was 3.38.
The age distribution of the population shows 11,895 people (21.4%) under the age of 18, 5,590 people (10.1%) aged 18 to 24, 13,585 people (24.5%) aged 25 to 44, 17,988 people (32.4%) aged 45 to 64, and 6,486 people (11.7%) who were 65 years of age or older. The median age was 41.0 years. For every 100 females, there were 95.2 males. For every 100 females age 18 and over, there were 92.3 males.
There were 18,455 housing units at an average density of 1,239.8 per square mile (478.7/km2), of which 14,513 (81.2%) were owner-occupied, and 3,367 (18.8%) were occupied by renters. The homeowner vacancy rate was 0.9%; the rental vacancy rate was 5.2%. 45,080 people (81.2% of the population) lived in owner-occupied housing units and 10,335 people (18.6%) lived in rental housing units.
According toMapping L.A., Chinese and Mexican were the most common ancestries. Korea and Taiwan were the most common foreign places of birth in 2000.[41]
The city is primarily divided into two Blue-ribbon districts. Diamond Bar students north of the city power lines are served by four elementary schools, one middle school, and one high school provided by the Pomona Unified School District.[47] Students south of the power lines running through the city are part of the Walnut Valley Unified School District and are served by nine elementary schools, three middle schools, and three high schools.[47]
