As an extension of the state, the county would conduct welfare and health programs, build and maintain roads, and hold courts of law. On March 29, 1973, the Georgia legislature increased the number of county commissioners from 3 to 5, also adding a county administrator. In 1990, the residents voted to unify the city and county governments creating Athens-Clarke County, the second (after Columbus-Muscogee County) unified city-county government in the state of Georgia. Clarke County is located at . The county is located in the Piedmont region of the state. The vast majority of Clarke County is located in the Upper Oconee River sub-basin of the Altamaha River basin, with a very small portion of the county's eastern edge, north of Winterville, located in the Broad River sub-basin of the Savannah River basin. According to the U.S. Census Bureau, the county has a total area of , of which is land and (1.5%) is water. It is the smallest county by area in Georgia. As of the census of 2000, there were 101,489 people, 39,706 households, and 19,694 families living in the county. The population density was 840 people per square mile (324/km²). There were 42,126 housing units at an average density of 349 per square mile (135/km²). The racial makeup of the county was 64.89% White, 27.25% Black or African American, 0.21% Native American, 3.13% Asian, 0.04% Pacific Islander, 3.08% from other races, and 1.41% from two or more races. 6.34% of the population were Hispanic or Latino of any race. There were 39,706 households out of which 22.50% had children under the age of 18 living with them, 32.60% were married couples living together, 13.30% had a female householder with no husband present, and 50.40% were non-families. 29.70% of all households were made up of individuals and 5.80% had someone living alone who was 65 years of age or older. The average household size was 2.35 and the average family size was 2.95. In the county, the population was spread out with 17.80% under the age of 18, 31.30% from 18 to 24, 27.40% from 25 to 44, 15.40% from 45 to 64, and 8.10% who were 65 years of age or older.