What is a Watershed?
A watershed is an area of land that drains to a common water body, such as a stream, large river, lake, wetland, bayou, or estuary. Smaller watersheds join to form larger watersheds and eventually basins.
In the example map, the Rhodes Branch watershed (red outline) encompasses 1,036 acres within the Ellington Creek watershed which encompasses 4,673 acres (yellow outline).
Both are nested within the 16,314 acre Ellington – Little Yellow Creek watershed which joins with many others across multiple states to ultimately form the Tennessee River basin that drains more than 40,000 square miles of land. The blue arrows show general water flow paths which converge within a given watershed and the green arrows show water flow paths that fall outside of the highlighted watersheds.
Keep in mind that watershed boundaries are determined by stream drainage areas rather than political delineations, and a watershed can cross county or state boundaries. This is why coordination and collaboration among water resource management agencies, at the state, regional and federal level, are critical to conservation efforts.
The Water Cycle and Water Quality
Clouds, rain, runoff, rivers, lakes, marshes, ground water, oceans – what’s the common thread? All have their place in the earth’s water cycle. After rain has fallen to the earth, it either remains in a water body, goes up into the atmosphere (evaporation and transpiration), goes down into the ground (infiltration) or flows over the land (runoff).
Stormwater runoff is the link in the water cycle most likely to degrade water quality. Runoff often carries dissolved chemicals, bacteria, and suspended matter like sediment (sand, silt, and clay soil particles) into our water bodies. In fact, many kinds of pollutants in the path of runoff may be transported to our streams and rivers. The proper care of the land, therefore, is essential for protecting water quality, our precious natural resources, the economy and human health.
Click here to learn some easy ways you can help do your part and be the solution to pollution!
