Introduction | How Does Water Get In and Out of the Ground?
Who Needs Groundwater? | Make an Aquifer!

The purpose of this activity is to understand how groundwater is trapped underground in aquifers!

Make it happen

1. Fill the cup with a material (sand, gravel, clay, or dirt) and pour water in the top. Repeat this trying out each material to figure out which is the most permeable (meaning water flows through it easily) and which is the least permeable (water doesn’t flow through it and gets stuck in the cup).

2. Now that you know more about materials that are found in the ground, you are ready to make an aquifer! Choose the material that you found to be the least permeable and make a layer of it at the bottom of the cup. Then, fill the rest of the cup with the material that is the most permeable.

3. Does your aquifer actually hold water? Pour some in and see!

4. Fill the cup and see how much water you can trap in your aquifer!

What’s happening?

Even though the cup is full of sand and dirt and stuff like that, some water can still go through it. The water will fill the pore spaces between the pieces of material. Which material holds the most water in it? Why do you think that is?

If there are few or no pore spaces in a material, then it will not let much water into it and it will not let water flow through it and out of the cup. Did you find a material that did not soak up much water and wouldn’t allow it to drain from the cup?

A good aquifer contains the water by having a less permeable layer of material below one that is very permeable.