What is a Watershed?

A watershed is an area of land that drains into a body of water. When rain falls it lands on trees, grass, homes, roads, farms, parking lots, gardens, schools and more. Natural surfaces absorb that water, but paved surfaces, buildings, and landscaped plots send most of the water flowing over land, downhill to nearby streams. We call that water runoff, and it carries with it anything that’s on the land – soil, fertilizer, trash and more. In our region, all of those streams eventually meet the Potomac River. You live in the Potomac Watershed and what you do on land affects the river!

Animated Watershed Definition