Watersheds and Wetlands CHAPTER 1

Watersheds & Wetlands Lesson 1.2 Chapter 1 Watersheds Pennsylvania’s Watersheds Chapter 1

PA Academic Standard for Environment & Ecology 4.1.10.A Describe changes that occur from a stream’s origin to its final outflow. Learning Objectives Students will identify Pennsylvania’s major watersheds and their related river systems and delineate these watershed boundaries. Students will describe changes in a river by tracing the river’s flow back to its headwaters and identifying major tributaries.

Watersheds What is a watershed? Definition: drainage basin; region drained by, or one that contributes water to, a stream, lake, or other body of water Watersheds are surrounded by topographic highs called divides. Definition: any ridge between two streams along which precipitation runs off

Example: The Continental Divide runs through Canada, the United States, Mexico, and into Central America. It creates the separation between water that drains into the Pacific Ocean and water that drains into the Atlantic Ocean. Continental Divide

Pennsylvania’s Watersheds All of the water that drains from Pennsylvania will eventually make its way to the Atlantic Ocean. Pennsylvania is organized into 104 watersheds, which are further divided into basins and sub-basins.

Pennsylvania’s Watersheds Great Lakes Basin (Erie & Genesee) Ohio River Basin Susquehanna/Chesapeake Basin Potomac Basin Delaware Basin

Covering almost half of the state, the Susquehanna River Basin is PA’s largest watershed Headwaters: New York State’s Otsego Lake Mouth: Chesapeake Bay The watershed in which you live, the Delaware River Basin, drains into the Delaware Bay Major tributaries include the Lehigh River and the Schuylkill River. Water from this basin provides much of NYC with it’s drinking water.

Ohio River Drainage Basin Potomac River Drainage Basin Pa’s second largest watershed (Largest overall) Drains 34% of PA Potomac River Drainage Basin Joins the Susquehanna River at the Chesapeake