As of the census2 of 2000, there were 3,849 people, 1,397 households, and 1,071 families residing in the township. The population density was 35.9/km² (92.9/mi²). There were 1,453 housing units at an average density of 13.5/km² (35.1/mi²). The racial makeup of the township was 98.08% White, 0.23% African American, 0.10% Native American, 0.23% Asian, 0.42% from other races, and 0.94% from two or more races. Hispanic or Latino of any race were 1.12% of the population.
There were 1,397 households out of which 37.9% had children under the age of 18 living with them, 66.4% were married couples living together, 6.7% had a female householder with no husband present, and 23.3% were non-families. 18.3% of all households were made up of individuals and 7.5% had someone living alone who was 65 years of age or older. The average household size was 2.75 and the average family size was 3.13.
In the township the population was spread out with 26.2% under the age of 18, 6.9% from 18 to 24, 30.6% from 25 to 44, 25.4% from 45 to 64, and 11.0% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 102.3 males. For every 100 females age 18 and over, there were 101.6 males.
The median income for a household in the township was $53,883, and the median income for a family was $61,520. Males had a median income of $38,510 versus $29,866 for females. The per capita income for the township was $22,688. About 2.1% of families and 4.1% of the population were below the poverty line, including 8.3% of those under age 18 and none of those age 65 or over.
The Township is served by the Northwestern Lehigh School District.