People have built dams for thousands of years. Modern dams are designed to be multi-purpose. They provide irrigation, flood control, water supply, electric power and recreation. Hydroelectric dams use the energy of falling water from reservoirs to produce electricity through the use of turbines.

Dams can be made from many things including rock, timber, embankments, masonry, and concrete. Construct an earthen dam and find out whether you can make it hold water!

You will need:

1/2 gallon milk carton (cut one side and the top off of the carton)

6 to 8 craft sticks, cut in half

Pottery clay

Sticks, gravel, dirt, pebbles

Building your Dam:

Glue the craft sticks together, side by side until they form a wall.

Glue the wall to the middle of the "floor" of the milk carton.

After the glue dries, form a triangle shape over the wall with the clay.

Add sticks, gravel or dirt over the clay layer, ending with a top layer of close fitting pebbles (in a real dam, this would be known as riprap).


You may want to mix your "loose" materials with clay sothey are more cohesive. Press all of the layers firmly down to form tight layers.

After you've constructed your dam, let it dry for 5 to 7 days. Then slowly pour water behind the dam.


Does your dam hold water?

Could wildlife survive in your type of dam?

Did you know...

The Oahe Dam in South Dakota gets its name from the Oahe Mission established among the Dakota (Sioux) Indians in 1874. The word "Oahe" roughly means "a foundation" or "a place to stand on."
Home | Trunks | Presenter Kits | Class Activities | Teaching Units | Contact Us