Only 3% of all the water on earth is fresh water!!!

Where is the fresh water?

76% - ice23% - groundwater1% - on the surface

Pretty amazing!

Note: This is a fake picture!

Used here to show percent of the iceberg above water.

Because of this property, only about 9% of an iceberg is above the water!

These pictures are real! Notice the part of the iceberg below water!

Ice has a lower density than water. That is why it floats in water!

Click to view video clip on the water cycle

Water Cycle

impermeable

permeable

What happens to the water when it hits the ground?

The above ground water (runoff) becomes part of a watershed.

The final stop for the water in a watershed is when it reaches the ocean.

Water is also stored underground

The saturated zone is the level where the pores between the soil particles are filled with water. It is called an aquifer.

The top of the saturated zone is called the water table. Its location changes based on the amount of water going underground.

What do you think happens to the water table during a drought?

http://www.windows.ucar.edu

Above the water table is the unsaturated zone. Here the pore spaces are filled mostly with air.

A

B

C

Pores are the spaces between soil particles where air and/or water can be found.

Click here for a video clip on underground water

We dig wells to get to the water stored in the aquifer. In fact, most of the bottled water we buy comes from there! The “confining” bed is impermeable so the water cannot go deeper into the ground.

Look how important underground water is to the water cycle!

Video clip on watersheds and wetlands (10 minutes)

Point andNon pointpollution

Video clip about non point

Can you answer these questions?

1. How much of the earth’s water is fresh water?2. What is an aquifer?3. Explain what a water table is.4. What does the word saturated mean?5. What is the difference between permeable and

impermeable?6. What is a watershed?7. Define wetlands.8. Why are wetlands important?9. What is the difference between point and non point

source pollution?