A watershed is the area of land that channels rainfall and snowmelt to creeks, streams, and rivers, and eventually to outflow points such as reservoirs, bays, and the ocean. This area can be as small as your backyard or large enough to cover half of the United States, since small watersheds combine with one another to create large drainage basins. The health of a watershed is vitally important for the health of its inhabitants, from plants to birds to trees to people. Individuals, families, and businesses can contribute toward overall watershed health by making their lawns and gardens creek-friendly.
You can use this link to find your watershed on the USGS map.