Tinicum Township is located in southeastern Delaware County at (39.868962, -75.288273). It is bordered to the south by the
Delaware River, to the west and northwest by
Darby Creek, and to the northeast by the city of
Philadelphia. The township borders the state of
New Jersey at the center of the Delaware River. The unincorporated community of Essington is in the western part of the township, and Lester is directly to its east. The western part of Philadelphia International Airport takes up nearly all of the center and eastern parts of the township. The John Heinz National Wildlife Refuge lies along Darby Creek on the northwestern side of the township. According to the
U.S. Census Bureau, the township has a total area of , of which is land and , or 34.33%, is water. It has a
humid subtropical climate (
Cfa) and average monthly temperatures in Essington range from 33.6 °F in January to 78.4 °F in July. The
hardiness zone is mainly 7b with a little area of 7a and the average annual absolute minimum temperature in Essington is 5.2 °F. [https://planthardiness.ars.usda.gov/ ==Demographics==