Water polution

Water polution

What do we use water for?

This diagram is called a mind map. It is a technique that can help you to organise and summarise your ideas. This mind map shows some of the ways that water is used to produce and transport a can of baked beans to a shop. Get learners to draw their own mind maps to show how water is used to make a pair of denim jeans, a pair of leather shoes and / or a loaf of bread. They may have to do some research in the library before they start the activity. Once completed, discuss the different mind maps as a class.

Polluted feelings

(Requirements: elastic bands)

Water quality is defined as water that is safe, drinkable and appealing to all life on Earth. In South Africa the scarce fresh water is decreasing in quality because of an increase in pollution and the destruction of river catchments, caused by urbanisation, deforestation, damming of rivers, destruction of wetlands, industry, mining, agriculture, energy use, and accidental water pollution. If all this pollution is going into our rivers then humans are not respecting our most valuable resource WATER.

Water pollution is, in fact, a major cause of concern in South Africa, and needs to be addressed as a matter of urgency. Allow your learners to experience the effects of water pollution on a water animal or organism by following this activity:

1. Take an elastic band and put it over your thumb.
2. Now twist it once and stretch it across the back of your hand before looping it over your little finger.
3. Take a deep breath and hold it in until you’ve completed step 4 (this simulates the feeling of an animal, such as an otter or heron, being trapped under water by litter and being unable to come up for air).
4. Without using your other hand, your teeth, or rubbing the hand against anything, remove the elastic band.
5. Now have learners describe the experience, answering questions like:

• Could you get free and come up for air?;
• Is it easy to get free from the elastic band?;
• How did it feel to be trapped?;
• Did the elastic band hurt your hand?; and
• What can you do to stop pollution?

Model of a polluted river

Working in groups of five, have learners make their own model of a polluted river. Each group will need:

• a source of water — hose / bucket of water
• to make the river — spade / trowel / guttering / halved swimming pool hose
• a dam — container / basin / 2 litre plastic bottle
• pollutants — harmless substitute ingredients from home, eg. sand, food colouring, lentils, etc.
• bottles / jars
• paper, pens and coloured pencils

STEP 1: Draw up a table listing pollutants that could find their way into a river that flows through a city.
STEP 2: Think of safe, easily obtainable, substitute ingredients from home that can be used to represent those pollutants.
STEP 3: Decide on the quantities of "pollutants" that you would like to add to your river. Give reasons for your choice.

Examples of "pollutants"

Pollutant	Substitute Ingredients	QTY
Insecticides / Pesticides	Powder paint	1 tablespoon
Heavy metals	Lentils	3 tablespoons
Chemicals	Food colouring	1 tablespoon
Litter	Sweet papers	2 handfuls
Sewage	Coffee	2 tablespoons

STEP 4: Design and build a short river in the school playground or in the classroom. You will need a source of water and a dam at the end.

STEP 5: Pour water into the model. As the water flows down the "river", the "pollutants" can be added at different places along the river.
STEP 6: Collect the "polluted" water at the end of the river. Fill a bottle with this dirty water.
STEP 7: Write a label for this water that shows the contents - both good and bad. The labelled bottle can be displayed in the classroom as a reminder of why you need purified tap water.
Now ask learners the following:

• By adding these pollutants to the river what impact would it have on the life in the river?
• Would you drink this water? Give a reason for your answer.
• Do you think humans RESPECT the river by adding these pollutants to the river? Explain.

As a research exercise, ask learners to find out how tap water is cleaned (purified) in their area.

Source : http://www.randwater.co.za/StarinYou/educators/b13_polution.asp