About Watersheds

What is a Watershed?

WatershedA watershed (also called a drainage basin) is a region of land where water from rain and snowmelt drains downhill into a body of water, such as a river, lake, wetland, sea, or ocean. A watershed divide is the boundary that physically separates one watershed from another. Precipitation that falls on one side of a divide will drain into one watershed, while precipitation that falls on the other side will drain into a another watershed. Some watersheds are very small -- only a few square acres, while others extremely large -- millions of square miles.

We all live in a watershed, but unlike a political boundary, it is determined by the topography of the earth. People living within a watershed may not share the same congressman, senator, or president, but they do share a common water supply. As a result, development within a watershed impacts everybody. Realizing this, communities are beginning to take a watershed approach to solve environmental problems, organizing themselves along watershed boundaries.