Water PollutionWater Pollution

Water can be polluted by •SEWAGE•FERTILISERS•PESTICIDES/HERBICIDES•TOXIC SUBSTANCES

Water Pollution

Sewage

Sewage is human waste. Without careful processing it can cause pollution and disease.

Fertilisers

•CONTAMINATE drinking water

•EUTROPHICATION

EUTROPHICATION

If too much fertiliser is used it runs off into streams and rivers.

The fertiliser makes river plants and algae grow really fast

The stream cannot support so much plant life, so the plants start to die.

As the plants die, they are rotted by bacteria which use up all the OXYGEN in the stream

Lack of oxygen causes the fish and other animals in the stream to die.

PESTICIDES and HERBICIDES can be washed into rivers and streams

This kills plant and animal life

Toxic Chemicals

•Toxic chemicals can build up in food chains causing birth defects and reproductive problems.

The Minimata Bay Tragedy