Eldridge is a census-designated place (CDP) in Sonoma County, California, United States. The population was 1,534 at the 2000 census. It is notably the home to the Sonoma Developmental Center, the largest facility serving the needs of persons with developmental disabilities in the state.
According to the United States Census Bureau, the CDP has a total area of 0.64 square miles (1.7 km²), all of it land.
Eldridge is named for James Eldridge who owned part of the Rancho Cabeza de Santa Rosa land grant.
As of the census of 2000, there were 1,534 people, 521 households, and 321 families residing in the CDP. The population density was 2,403.1 people per square mile (925.4/km²). There were 551 housing units at an average density of 863.2/sq mi (332.4/km²). The racial makeup of the CDP was 85.92% White, 1.96% African American, 0.78% Native American, 2.80% Asian, 0.20% Pacific Islander, 4.04% from other races, and 4.30% from two or more races. Hispanic or Latino of any race were 13.95% of the population.
There were 521 households out of which 35.9% had children under the age of 18 living with them, 46.3% were married couples living together, 10.4% had a female householder with no husband present, and 38.2% were non-families. 30.3% of all households were made up of individuals and 5.8% had someone living alone who was 65 years of age or older. The average household size was 2.44 and the average family size was 3.10.
In the CDP the population was spread out with 22.7% under the age of 18, 6.3% from 18 to 24, 35.5% from 25 to 44, 29.1% from 45 to 64, and 6.3% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 99.7 males. For every 100 females age 18 and over, there were 94.4 males.
The median income for a household in the CDP was $52,656, and the median income for a family was $62,500. Males had a median income of $35,426 versus $34,886 for females. The per capita income for the CDP was $24,076. None of the families and 16.3% of the population were living below the poverty line, including no under eighteens and 11.8% of those over 64.
In the state legislature Eldridge is located in the 2nd Senate District, represented by Democrat Pat Wiggins, and in the 6th Assembly District, represented by Democrat Jared Huffman. Federally, Eldridge is located in California's 6th congressional district.