The WHO (World Health Organization) says that a person needs 19 litres of water a day. One in three Asians does not have safe drinking water, and one in two has no sanitation

Agriculture

Animals. Like humans, animals need to drink water to survive.

Irrigation. Plants need water, too. So farmers use it to help their crops to grow. With water, dry land can produce crops. When there is no rain, irrigation is necessary for agriculture.

Fish. Fish live in fresh water. In lakes and rivers. Many fish live in salt water, in the ocean. These fish are wild, but now there are also fish farms in many countries.

Industry

Machinery. Machines use water.

Transport. We transport things by water. Ships travel on the seas, rivers and canals.

Energy. Countries where it rains a lot, or with high mountains, use water to produce electricity.

The WHO says that the largest water users are: agriculture (70%), industry (20%) and domestic use (10%).

Identifying water problems

We all need water. The problem is there’s often too much – or too little. And there are other problems, too. Let’s look at some of them.

Quantity

Too much: When it rains a lot, the level of the rivers rises. The water runs over the banks. People often drown. Their cars and houses are ruined. Animals drown, too. Many big cities in Asia, Latin America and Europe often have floods.

Too little: Sometimes it doesn’t rain for a long time. Plants die. Animals die, too. People have no food. Many countries in Africa have big problems with droughts. Every year, these droughts get worse and worse.

Pollution

Industry often pollutes water with chemicals. Some farmers also use too many chemicals. These enter the rivers and lakes. They kill the plants and fish.

Politics

Every country wants water for its people. So they build dams to collect it, and to produce hydroelectricity. Sometimes they divert rivers to provide more water. But this often affects other countries. The River Nile is very important for Egypt. The Blue and White Niles rise in Ethiopia and Sudan, in the south. The countries there want to take more of the water before it goes to Egypt. It’s not only a problem between one country and another. Different communities inside a country need water for different purposes. In Spain, there are plans to build a big dam on the River Ebro to provide irrigation for farmers. But the fishermen at the mouth of the river do not want this. It will destroy the fish and affect their lives.

Global warming

The world is getting warmer, so the water levels are rising. Climates are changing. Some countries are becoming hotter and drier. This affects agriculture. People want to control global warming, but they cannot agree about the best solutions.

2. Air pollution. Air pollution influents the health of people. For example: ultraviolet radiation from the sun can cause skin cancer. Normally the ozone layer in the atmosphere protects us from such radiation, but if there are holes in the ozone layer ultraviolet radiation can get to the earth. Many scientists think that these holes are the result of air pollution. Also we have problems with nuclear pollution. Nuclear pollution cannot be seen but its effect can be terrible. To make air clean again we need good filters at nuclear power stations, at factories, in cars and buses.

3. The growth of population. People don't have enough places to live. They need more water, more food. So it is the reason of the shortage of the natural resources. It is very difficult to solve this problem. Also one of the most serious problems is greenhouse effect. It works like this: the sunlight gives us heat. Some of the heat warms the atmosphere and some of the heat goes back into space. Nowadays the heat can't go into space. That's why winter and summer temperatures in many places have become higher. If the temperature continues growing up, the snow on the mountains and ice will melt, so the most of the earth will be under water. So every person has to understand how important it is to solve these problems, which endanger people's life.

IV. Answer the following questions:

1. What is the air polluted by?

2. Are rivers polluted?

3. Can you see pollution at the seaside?

4. What are the most serious environmental problems now?

5. What is the Global warming?

6. What kinds of ecological problems are there nowadays?

7. Identify an environmental problem in your town or country. Is there a solution?