2000 48,553 1990 42,647 1980 28,252 1970 16,881
As of the census of 2000, there were 48,553 people, 14,175 households, and 11,963 families residing in the CDP. The population density was 5,380.7 people per square mile (2,078.3/km²). There were 14,543 housing units at an average density of 1,611.7/sq mi (622.5/km²). The racial distribution of the CDP was 29.26% White, 2.61% African American, 0.46% Native American, 50.32% Asian, 0.31% Pacific Islander, 12.83% from other races, and 4.22% from two or more races. Hispanic or Latino of any race were 28.32% of the population.
There were 14,175 households out of which 41.2% had children under the age of 18 living with them, 64.4% were married couples living together, 13.5% had a female householder with no husband present, and 15.6% were non-families. 11.4% of all households were made up of individuals and 3.7% had someone living alone who is 65 years of age or older. The average household size was 3.41 and the average family size was 3.64.
In the CDP the population was spread out with 26.0% under the age of 18, 10.2% from 18 to 24, 30.4% from 25 to 44, 24.6% from 45 to 64, and 8.8% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 96.8 males. For every 100 females age 18 and over, there were 93.5 males.
The median income for a household in the CDP was $52,270, and the median income for a family was $56,065. Males had a median income of $40,669 versus $30,432 for females. The per capita income for the CDP was $19,315. About 9.5% of families and 12.0% of the population were below the poverty line, including 13.9% of those under age 18 and 9.9% of those age 65 or over.
Foothill Transit and the Metro provide bus transit services throughout the San Gabriel Valley. The main Metro Bus Terminal is in El Monte. In addition, the Metrolink commuter train runs west towards Downtown Los Angeles and east to San Bernardino through the Valley.
Several cities such as Monterey Park and West Covina provide their own in-city transportation shuttles. The fare is usually 25 cents.
The San Gabriel Valley is served by several major freeways, including the San Bernardino Freeway (Interstate 10), Foothill Freeway (I-210), San Gabriel River Freeway (I-605), and the Long Beach Freeway (I-710). State highways include the Orange Freeway (State Route 57), the Pomona Freeway (State Route 60), Ventura Freeway (State Route 134), and the Pasadena Freeway (State Route 110).
The Long Beach Freeway (I-710) ends abruptly (or begins, depending on one's perspective) on the western border of Alhambra, near California State University, Los Angeles. For several years, the extension of the 710 Freeway to the 110 Freeway in Pasadena has generated a long, controversial, and contentious debate. Many residents in South Pasadena fear losing their homes and businesses to clear the way for construction. The MTA, an ardent proponent of the extension, has proposed the idea of constructing an underground tunnel connecting the two freeways.
In 2002, the Foothill Freeway was extended beginning from San Dimas and La Verne, just outside of the San Gabriel Valley area. It replaced the State Route 30 and it reaches into San Bernardino County.
State Route 39 (Azusa Avenue and San Gabriel Canyon Road) leads north into the San Gabriel Mountains to the Crystal Lake Recreation Area. The portion connecting to the Angeles Crest Highway (State Route 2) is inaccessible and has been closed off since the early 1970s due to rockslides.
China Airlines operates private bus services to Los Angeles International Airport from Hong Kong Super Market at 18414 Colima Road in Rowland Heights, 91748 to feed its flight to Taipei, Taiwan.