Okauchee Lake, Wisconsin  Okauchee Lake is a census-designated place (CDP) in Waukesha County, Wisconsin, United States. The population was 4,422 at the 2010 census. Okauchee Lake is located in the town of Oconomowoc. Okauchee Lake is located at (43.119454, -88.439839). According to the United States Census Bureau, the CDP has a total area of 4.9 square miles (12.6 km²), of which, 3.4 square miles (8.8 km²) of it is land and 1.5 square miles (3.8 km²) of it (30.00%) is water. At the 2000 census there were 3,916 people, 1,511 households, and 1,119 families in the CDP. The population density was 1,126.7 people per square mile (434.5/km²). There were 1,711 housing units at an average density of 492.3/sq mi (189.8/km²). The racial makeup of the CDP was 98.60% White, 0.20% African American, 0.05% Native American, 0.15% Asian, 0.03% Pacific Islander, 0.26% from other races, and 0.72% from two or more races. Hispanic or Latino of any race were 0.66%. Of the 1,511 households 33.2% had children under the age of 18 living with them, 67.0% were married couples living together, 4.4% had a female householder with no husband present, and 25.9% were non-families. 19.3% of households were one person and 5.6% were one person aged 65 or older. The average household size was 2.59 and the average family size was 3.02. The age distribution was 24.3% under the age of 18, 5.6% from 18 to 24, 30.8% from 25 to 44, 30.3% from 45 to 64, and 9.0% 65 or older. The median age was 40 years. For every 100 females, there were 108.4 males. For every 100 females age 18 and over, there were 108.7 males. The median household income was $66,042 and the median family income was $73,300. Males had a median income of $47,420 versus $31,985 for females.