What is a Watershed?
A watershed is simply the geographic area through which water flows across the land and drains into a common
body of water, whether a stream, river, lake, or ocean. The watershed boundary will more or less follow the
highest ridgeline around the stream channels and meet at the bottom or lowest point of the land where water
flows out of the watershed, the mouth of the waterway.
Much of the water comes from rainfall and stormwater runoff. The quality and quantity of stormwater is
affected by all the alterations to the land--mining, agriculture, roadways, urban development, and the
activities of people within a watershed. Watersheds are usually separated from other watersheds by naturally
elevated areas.
Why are Watersheds Important?
Watersheds are important because the surface water features and stormwater runoff within a watershed
ultimately drain to other bodies of water. It is essential to consider these downstream impacts when
developing and implementing water quality protection and restoration actions. Everything upstream ends up
downstream. We need to remember that we all live downstream and that our everyday activities can affect
downstream waters.