Photo of Whipple Dam State Park in Jackson Township, Huntingdon County, Pennsylvania. In the 1860s Osgood M. Whipple (1840-1899) purchased a large tract of land and built a water-powered sawmill. He also built a dam to create a lake that powered the sawmill. After Osgood left the lumber business in 1897, the dam remained and has been used for recreation ever since.