Watershed in a pan

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. We all live in a watershed!

Let's make a model of a watershed in a pan!

For this activity you will create a watershed by placing the foil over cups, glasses, crumpled up newspapers, or found items to create a simulated landscape with mountains, valleys, and a lowland area. All parts of the foil should drain into the single low area. The outer edges should be turned upward to keep the water on the surface of the foil.

Materials needed

Baking dish or plastic tub

Aluminum foil

Cups, glasses, newspaper, or any material found around the house

Spray bottle with water (optional: add two drops of blue food coloring to water)

Measuring cup

Procedure, Part 1

1. Place cups, glasses, etc upright on one side of the baking pan to represent mountains

2. Leave one end of the pan empty to represent a low lying area

3. Cover the entire pan with aluminum foil, gently molding the foil around the objects in the pan

4. Add 1/2 cup of water to measuring cup and pour into spray bottle

5. Make it rain! Use the spray bottle to make it rain on the mountains you created

Observe how the water moves in the watershed. Note how much water moved through the watershed. Was some water retained in/on the watershed? What do these bodies of water represent? Catch all the runoff water in the cup at the low area.

Can you identify these parts of the watershed on your model?

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.

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.

Procedure, Part 2

For part 1 we made one mountain range. Now let's make two mountain ranges!

1. Place cups, glasses, etc upright on both ends of the baking pan to represent mountains

2. Leave the area in the middle of the pan empty to represent a valley

3. Reuse the aluminum foil to cover the entire pan, gently molding the foil around the objects in the pan

4. Add 1/2 cup of water to measuring cup and pour into spray bottle

5. Make it rain! Use the spray bottle to make it rain in the mountains you created

Observe how the water moves in the watershed. How many watersheds were created? Note how much water moved through each watershed. Did the water flow to a common area? Can you identify the ridgelines that mark the boundaries of each watershed? Catch all the runoff water in the cup at the low area.

*Save your watershed model to use with Unit 3 Protecting Our Watersheds.