Almost 80% of the earth's surface is covered with water.

Ninety-seven percent of the water on earth is salt water. Salt water is filled with salt and other minerals. Humans cannot drink this water. It is too difficult and expensive to remove the salt. Two percent of the water on earth is glacier ice at the North and South Poles. This ice is fresh water and could be melted down. It is too far away from where people live to be usable. Less than 1% of all the water on earth is fresh water that we can actually use. We use this small amount of water for drinking, transportation, heating and cooling, industry and many other purposes.