watershed

The area of land where the water that is under it or that drains from it, and is carried into a larger body of water, is called a watershed. In Flower Mound, there are rivers that would go into Lake Lewisville or Grapevine. Maintaining clean and healthy watersheds allow ecosystems and habitats for fish populations to thrive. It is also much more economically efficient to keep the watersheds healthy and clean rather than trying to repair and fix them. It also is a storage for a clean water supply.
picture: http://water.epa.gov/polwaste/nps/watershed/images/streams_lakes_2.jpg