A watershed is the area of land where all of the water that falls in it and drains off it goes into the same place. Watersheds can be as small as a footprint or large enough to encompass all the land that drains water into rivers that drain into the Chesapeake Bay, where it enters the Atlantic Ocean. A watershed is an area of land that drains all the streams and rainfall to a common outlet such as the outflow of a reservoir, mouth of a bay, or any point along a stream channel. The word watershed is sometimes used interchangeably with drainage basin or catchment. Ridges and hills that separate two watersheds are called the drainage divide. The watershed consists of surface water-lakes, streams, reservoirs, and wetlands- and all the underlying groundwater. Larger watersheds contain many smaller watersheds. Watersheds are important because the streamflow and the water quality of a river are affected by things, human-induced or not, happening in the land area “above” the river-outflow point.
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Outline of the 6 major watershed basins in Pennsylvania. The larger basins are composed of many smaller watersheds. The map below shows all of the watersheds that are located within Elk County. It is important to note that the county is divided in terms of where all the water ends up. The Eastern Continental Divide splits the county. Water on the eastern side of the divide ends up in the Chesapeake Bay, while the western side of the divide ends up in the Mississippi River. This is a good display as to how important it is to protect our waters; pollution events in Elk County eventually end up effecting a lot of other people downstream. This is the case with any water pollution event. It is important to remember that there are always neighbors down stream!