Limited supply
We often take water for granted. It comes out of the tap. You can buy it in convenience stores. But only about 3 per cent of the water in the world is fresh water. The rest is salt water. It is very expensive to turn salt water into fresh water.
Here?s another problem. Nearly 70 per cent of the fresh water is frozen ? in glaciers and the ice caps.
Water is what scientists call a limited resource. We need it, but there is only so much of it. And the world population is growing every day. Only half the people in the world have access to tap water. Most water is used for agriculture and industry. If there is a serious water shortage, it will affect food supplies ? and prices.
In the fields
Nearly 70 per cent of our fresh water goes to producing the vegetables, grains and meat we eat. Meat uses the most water. It takes about 1,400 litres of water to produce a kilogram of rice. But to get a kilogram of beef to the supermarket shelves, it takes 13,000 litres. Next time you order a hamburger, think about the fact that nearly 5,000 litres of water were used to get it on your plate.
