Water pollution

Sources of water

Clean water is one of our most important natural resources. We cannot survive without it. Water is used for drinking, bathing, washing, cooking and agriculture among other things. The water that people use comes from many sources including:

Rivers: A river is a body of water that flows in a channel.

Lakes: A lake is a large body of water which is completely surrounded by land.

Springs: A spring is a place where water flows naturally out of the ground.

Groundwater: This is water which is found underground in the soil or rock. We can access groundwater by digging deep hole called a well.

How does water become polluted?

Water pollution is the introduction of harmful substances into various water bodies. This can happen in many ways including:

Wastewater from homes: The wastewater that leaves our homes from our bathrooms and sinks often contains products like soap, dishwashing liquid, shampoo and bleach. These products often contain harmful substances which can pollute the environment. The wastewater from our homes enter drains which often lead to rivers which then flow into the sea.

The water which flows out of our homes can contain harmful chemicals.

Sewage: In some areas raw sewage is released into rivers or the sea. The bacteria found in sewage can cause diseases.

Agriculture: Pesticides and other chemicals are often used when growing crops. When it rains, these chemicals can mix with rainwater and flow into rivers which then flow into the sea. These chemicals may also seep into the soil and pollute groundwater. Also, animal waste from farms can cause pollution if it enters a body of water such as a river or lake.

Improper disposal of garbage: Some people dump garbage into rivers or the sea. Items such as plastic wrappers or bottles are sometimes thrown into drains. These items get washed into rivers or the sea when it rains. Sometimes, garbage dumped onto the land contains harmful substances which can seep into the soil and pollute groundwater.

The surface of this river is almost completely covered with garbage.

Waste from industries: Some industries produce harmful waste such as toxic chemicals and other pollutants. Sometimes this waste is dumped into rivers or other bodies of water. Sometimes, this waste may enter the soil and pollute groundwater. For instance, mining for gold can pollute nearby rivers or groundwater. Also, factories often dump their wastewater into nearby rivers.

Waste from a factory is being dumped into a nearby stream.

Effects of water pollution

Drinking polluted water can cause people to fall ill or die.
Many animals and plants which live in or near water bodies are harmed or killed when the water becomes polluted.
Eating animals such as fish which are caught in polluted water can cause people to become sick.
Water pollution can damage the ecosystems in and near rivers, seas or other bodies of water.