The water cycle

 
When rain or snow falls on the ground, some of it travels slowly down through the ground to the aquifers. As water makes its slow journey, it is filtered by soil, sand and gravel. This water is called groundwater.  Some of the rainwater runs over the land into lakes, rivers, and streams. This water is called surface water.  The sun heats water to form clouds and begin the cycle again.

What is a watershed?

A watershed is an area of land that catches rain and snow and where water flows downward into a specific river, stream, lake, or aquifer. All land is part of a watershed and we all live in a watershed. 

What is an aquifer?

Groundwater aquifers are largely underground areas within layers of rock or substrate that hold water to some extent. They are maintained by rainfall and inflow from lakes and streams above ground, combined with natural and human-caused outflow.