within the city of Janesville and the surrounding area. Geography Janesville is located at (42.646008, -92.462663). The city is located on the county line between Bremer and Black Hawk counties, and is bisected by the Cedar River. According to the United States Census Bureau, the city has a total area of , of which is land and is water. Demographics 2010 census As of the census of 2010, there were 930 people, 398 households, and 262 families residing in the city. The population density was . There were 409 housing units at an average density of . The racial makeup of the city was 98.4% White, 0.6% African American, 0.2% Asian, and 0.8% from two or more races. Hispanic or Latino of any race were 0.3% of the population. There were 398 households, of which 29.1% had children under the age of 18 living with them, 56.8% were married couples living together, 6.3% had a female householder with no husband present, 2.8% had a male householder with no wife present, and 34.2% were non-families. 28.1% of all households were made up of individuals, and 13.6% had someone living alone who was 65 years of age or older. The average household size was 2.34 and the average family size was 2.90. The median age in the city was 40.2 years. 24.2% of residents were under the age of 18; 6.4% were between the ages of 18 and 24; 25.5% were from 25 to 44; 25.3% were from 45 to 64; and 18.5% were 65 years of age or older. The gender makeup of the city was 49.6% male and 50.4% female. 2000 census As of the census of 2000, there were 829 people, 349 households, and 246 families residing in the city. The population density was . There were 359 housing units at an average density of . The racial makeup of the city was 99.16% White, 0.36% Asian, and 0.48% from two or more races. Hispanic or Latino of any race were 0.24% of the population. There were 349 households, out of which 29.2% had children under the age of 18 living with them, 58.2% were married couples living together, 9.7% had a female householder with no husband present, and 29.5% were non-families. 25.8% of all households were made up of individuals, and 12.3% had someone living alone who was 65 years of age or older. The average household size