The importance of water

Water is one of the most important substances on earth. All plants and animals must have water to survive. If there was no water there would be no life on earth.


Apart from drinking it to survive, people have many other uses for water. These include:

• cooking
• washing their bodies 
• washing clothes
• washing cooking and eating utensils; such as billies, saucepans, crockery and cutlery
• keeping houses and communities clean
• recreation; such as swimming pools
• keeping plants alive in gardens and parks

Water is also essential for the healthy growth of farm crops and farm stock and is used in the manufacture of many products.

Fig. 6.2: Some domestic uses of water.

It is most important that the water which people drink and use for other purposes is clean water. This means that the water must be free of germs and chemicals and be clear (not cloudy).

Water that is safe for drinking is called potable water.

Disease-causing germs and chemicals can find their way into water supplies. When this happens the water becomes polluted or contaminated and when people drink it or come in contact with it in other ways they can become very sick.

Water that is not safe to drink is said to be non-potable. Throughout history there have been many occasions when hundreds of thousands of people have died because disease-causing germs have been spread through a community by a polluted water supply.

One of the reasons this happens less frequently now is that people in many countries make sure drinking water supplies are potable. Water supplies are routinely checked for germs and chemicals which can pollute water. If the water is not safe to drink it is treated. All the action taken to make sure that drinking water is potable is called water treatment.