Ouachita Parish (French: Paroisse d’Ouachita) is located in the northern part of the U.S. state of Louisiana. As of the 2010 census, the population was 153,720. The parish seat is Monroe. The parish was formed in 1807.
According to the U.S. Census Bureau, the parish has a total area of 632 square miles (1,640 km), of which 610 square miles (1,600 km) is land and 21 square miles (54 km) (3.4%) is water.
As of the census of 2000, there were 147,250 people, 55,216 households, and 38,319 families residing in the parish. The population density was 241 people per square mile (93/km²). There were 60,154 housing units at an average density of 98 per square mile (38/km²). The racial makeup of the parish was 64.48% White, 33.63% Black or African American, 0.23% Native American, 0.64% Asian, 0.03% Pacific Islander, 0.33% from other races, and 0.67% from two or more races. 1.19% of the population were Hispanic or Latino of any race.
There were 55,216 households out of which 34.20% had children under the age of 18 living with them, 47.70% were married couples living together, 17.90% had a female householder with no husband present, and 30.60% were non-families. 25.80% of all households were made up of individuals and 9.30% had someone living alone who was 65 years of age or older. The average household size was 2.58 and the average family size was 3.12.
In the parish the population was spread out with 27.90% under the age of 18, 12.00% from 18 to 24, 27.90% from 25 to 44, 20.30% from 45 to 64, and 11.80% who were 65 years of age or older. The median age was 32 years. For every 100 females there were 89.30 males. For every 100 females age 18 and over, there were 84.50 males.
The median income for a household in the parish was $32,047, and the median income for a family was $40,206. Males had a median income of $31,616 versus $23,139 for females. The per capita income for the parish was $17,084. About 15.80% of families and 20.70% of the population were below the poverty line, including 29.70% of those under age 18 and 15.80% of those age 65 or over.