A watershed is an area of land that drains precipitation from the highest point to the lowest. Like a funnel, it takes water from a large area and channels it all together before releasing it to the ocean. Link to this map https://frysrun.org/maps to see if you live in the Frys Run Watershed. If not, the Lehigh Valley Planning Commission has a map https://www.lvpc.org/pdf/maps/streamQuality.pdf that will help you see which watershed you live in.
Right here in our neighborhood there are 2 watersheds that we can easily trace on their journey to the ocean. Frys Run starts in Hellertown, outlets to the Delaware at the park on 611, and flows from there into the Atlantic. Silver Creek in Hellertown flows into the Saucon Creek, then to the Lehigh, into the Delaware in Easton, and then to the ocean. In Pennsylvania there are 3 major watersheds, the Delaware, the Susquehanna, and the Ohio.
We all live in a watershed. In includes the land as well as all the streams, rivers, lakes or ponds that are in its boundaries. It has no political borders, it continues across township lines, county lines, state lines and international lines.
Picture the roof of your house from its highest peak. In a rain storm water flows from the top down one side to the front lawn, down one side to the back lawn. This is how a watershed divide looks from above. This picture that depicts a watershed shows how some rain is absorbed by plants and trees, some percolates underground to become our drinking water, and the rest goes on its way to the ocean.