Streams are bodies of water that carry along a clearly defined path, called a channel. Streams may vary in width from a few centimeters to several kilometers. Streams are important for several reasons:
- They carry most of the water that goes from land to the sea. Therefore are important for the water cycle.
- They are a major part of the process of erosion. A lot of the surrounding landscapes are controlled by stream erosion.
- Streams are a major source of water and transportation.
Many forms of wildlife depend on clean streams in order to thrive. Pennsylvania stream systems are abundant with fishes and other wildlife that rely on streams for habitat and life. Stream systems in Elk County include: Bear Run, Little Mill Creek, Dents Run, Laurel Run, Elk Creek, and Millstone Creek.