Sherburne County is a county in the U.S. state of Minnesota. At the 2010 United States Census, the population was 88,499. The county seat is Elk River.
The Mississippi River flows southeast along the county’s south border. The Rum River flows southeast through the county’s upper east portion. The Elk River rises in nearby Benton County, and flows south-southeast through the western and southern part of Sherburne County, discharging into the Mississippi at Elk River. The Saint Francis River also rises in Benton and flows southward through the central part of Sherburne County, discharging into the Elk just north of Big Lake.
The terrain of Sherburne County consists of low rolling hills, partially wooded, heavily sprinkled with lakes, ponds and depressions. The soil of Sherburne County contains considerable sand and gravel due to glacial activity in past epochs, and thus is less suitable for agriculture than much of Minnesota. The county terrain slopes to the south and east. The county’s highest point lies 3 miles (5 km) east-southeast of Saint Cloud, at 1,110′ (338m) ASL. The county has a total area of 451 square miles (1,170 km), of which 433 square miles (1,120 km) is land and 18 square miles (47 km) (4.0%) is water.
At the 2000 United States Census, there were 64,417 people, 21,581 households and 16,746 families in the county. The population density was 148/sqmi (57.4/km²). There were 22,827 housing units at an average density of 52.7/sqmi (20.4/km²). The county’s racial makeup was 96.73% White, 0.85% Black or African American, 0.45% Native American, 0.58% Asian, 0.02% Pacific Islander, 0.43% from other races, and 0.95% from two or more races. 1.10% of the population were Hispanic or Latino of any race. 40.1% were of German, 13.6% Norwegian, 7.5% Swedish and 6.2% Irish ancestry.
There were 21,581 households of which 44.90% had children under the age of 18 living with them, 66.20% were married couples living together, 7.50% had a female householder with no husband present, and 22.40% were non-families. 15.70% of all households were made up of individuals and 5.20% had someone living alone who was 65 years of age or older. The average household size was 2.91 and the average family size was 3.27.
The county population contained 30.9% under the age of 18, 9.60% from 18 to 24, 33.90% from 25 to 44, 18.40% from 45 to 64, and 7.10% who were 65 years of age or older. The median age was 31 years. For every 100 females there were 104.30 males. For every 100 females age 18 and over, there were 103.20 males.
The median household income was $57,014 and the median family income was $61,790. Males had a median income of $41,601 and females $27,689. The per capita income for the county was $21,322. About 2.30% of families and 4.40% of the population were below the poverty line, including 3.50% of those under age 18 and 10.10% of those age 65 or over.