A watershed is an area of land that drains into a body of water, such as a river, lake, reservoir, estuary, sea or ocean. The watershed includes the network of rivers, streams and lakes that convey the water, as well as the land surfaces from which water runs off. Watersheds are separated from adjacent watersheds by high points, such as mountains, hills, and ridges.

Like most bodies of water, lakes serve as the drinking water supplies for large cities and small towns throughout the State, provide flood control to protect life and property, and support significant sectors of our economy including recreation, tourism, agriculture, fishing, power generation, and manufacturing.

Rivers serve as tunnels, they are used to carry water into larger bodies.