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What Is a Watershed
Watersheds are nature's way of dividing up the landscape. Rivers, lakes, estuaries, wetlands, streams, even the oceans can serve as catch basins for the land adjacent to them. Ground water aquifers serve the same purpose for the land above them. The actions of people who live within a watershed affect the health of the waters that drain into it.
John Wesley Powell -- scientist, geographer, and leader of the first expedition through the Grand Canyon in 1869-- perhaps described it best when he said that a watershed is:
"that area of land, a bounded hydrologic system, within which all living things are inextricably linked by their common water course and where, as humans settled, simple logic demanded that they become part of the community."
