The watershed

What is a watershed?

A watershed is an area of land that collects water from rain or snow. The water collected in the watershed seeps into the ground or flows downstream into rivers, streams, and lakes.

Here is a picture of a watershed. The purple dashed line marks the boundary of the watershed.

A basic sketch of a watershed's elements.

A watershed is so much more than just a watershed

Many different parts make up a watershed:

Precipitation is water that falls to the earth as rain and snow and flows into streams and is absorbed into the ground for plants to take up in their roots.

The headwaters are the places where streams begin, usually the highest point.

Small tributary streams flow into one another to make larger streams. Larger streams join to form rivers.

A floodplain is an area that can become flooded when a river or stream overflows.

An estuary is the area where the river meets the ocean. Fresh water from the river and salt water from the ocean mix here.

A ridgeline is the top edge of the mountain that divides one watershed from another.


Now that you know a little about what a watershed is, let’s move on to the water cycle:

CSERC arrow