Lake Township is a township located in Mercer County, Pennsylvania. As of the 2000 census, the township had a total population of 706.
According to the United States Census Bureau, the township has a total area of 41.4 km˛ (16.0 mi˛). 41.1 km˛ (15.9 mi˛) of it is land and 0.4 km˛ (0.2 mi˛) of it is water. The total area is 0.94% water.
As of the census2 of 2000, there are 706 people, 232 households, and 187 families residing in the township. The population density is 17.2/km˛ (44.5/mi˛). There are 246 housing units at an average density of 6.0/km˛ (15.5/mi˛). The racial makeup of the township is 98.44% White, 0.57% African American, 0.00% Native American, 0.00% Asian, 0.00% Pacific Islander, 0.00% from other races, and 0.99% from two or more races. 0.00% of the population are Hispanic or Latino of any race.
There are 232 households out of which 37.1% have children under the age of 18 living with them, 72.8% are married couples living together, 5.2% have a female householder with no husband present, and 19.0% are non-families. 16.4% of all households are made up of individuals and 8.6% have someone living alone who is 65 years of age or older. The average household size is 3.04 and the average family size is 3.40.
In the township the population is spread out with 31.4% under the age of 18, 7.4% from 18 to 24, 25.2% from 25 to 44, 23.1% from 45 to 64, and 12.9% who are 65 years of age or older. The median age is 35 years. For every 100 females there are 99.4 males. For every 100 females age 18 and over, there are 98.4 males.
The median income for a household in the township is $36,591, and the median income for a family is $41,875. Males have a median income of $30,417 versus $19,821 for females. The per capita income for the township is $14,690. 10.4% of the population and 5.5% of families are below the poverty line. Out of the total population, 15.6% of those under the age of 18 and 6.7% of those 65 and older are living below the poverty line.