2.   DEFINITION OF WATER POLLUTION

• Contamination of water bodies such as lakes, rivers, oceans and groundwater caused by human activities which can be harmful to organisms and plants which live in these water bodies.

• Water pollution is any chemical, physical or biological change in the quality of water that has a harmful effect on any living things that drink, use or live (in) it. When humans drink polluted water, it oftens has serious effects on their health. Water pollution can also make water unsuited for desired use.

3.   TYPES OF WATER POLLUTANTS AND THEIR SOURCES

1. Nutrients pollution Some waste water, fertilizers and sewage contain high levels of nutrient. If they end up in water bodies, they encourage algae and weed growth in the water which can make the water undrinkable and even clog filters. Too much algae will also use up all the oxygen in the water and other water organisms in the water will die out of oxygen from starvation.

2. Surface water pollution Surface water includes natural water found on the earth’s surface like rivers, lakes, lagoons and oceans. Hazardous substances coming into contact with this surface water dissolving or missing physically with the water can be called surface water pollution.

3. Oxygen depleting Water bodies have microorganisms. These include aerobic and anaerobic organisms. When too much biodegradable matter (things that easily decay) end up in water, it encourages more microorganism growth and they use up more oxygen in the water. If oxygen is depleted, aerobic organisms die and anaerobic organism grow more to produce harmful toxins such as ammonia and sulfides.

4. Ground water pollution When humans apply pesticides and chemicals to soils, they are washed up deep into the ground by rain water. This gets to underground water, causing pollution underground. This means when we dig wells and bore holes to get water from underground, it needs to be checked for ground water pollution.

5. Microbiological In many communities in the world, people drink untreated water (straight from a river or stream). Sometimes there is natural pollution caused by microorganisms like viruses, bacteria and protozoa. This natural pollution can cause fishes and other water life to die. They can also cause serious illness to humans who drink from such waters.

6. Suspended matter Some pollutants (substances, particles and chemicals) do not easily dissolve in water. This kind of material is called particulate matter. Some suspended pollutants later settle under the water body. This can harm and even kill aquatic life that live at the floor of water bodies.

7. Chemical water pollution Many industries and famers work with chemicals that end up in water. These include chemicals that are used to control weeds, insects and pests.

Metals and solvents from industries can pollute water bodies. These are poisonous to many forms of aquatic life and may slow their development to make them interfile and kill them.

6. Oil spillage Oil spills usually have only a localized affect on wildlife but can spread for miles. The oil can cause death of many fish and stick to the feathers of seabirds causing them to lose the ability to fly. Do you remember the BP Oil Spill in 2010? Over 1000 animals (birds, turtles, mammals) were reported dead including many already on the endangered species list. Of the animals affected by the spill that are still alive only about 6% have been reported cleaned but many biologists and other scientists predict they will die too from the stress caused by pollution.

7.   EFFECTS OF WATER POLLUTION ON LIVING THINGS

Death of aquatic (water) animals The main problem caused by water pollution is that it kills life that depends on these water bodies. Dead fish, crabs, birds and sea gulls, dolphins and many other animals often wind up on beaches, killed by pollutants in their habitat (living environment.

Disruption of food-chains Pollution disrupts the natural food chain as well. Pollutants such as lead and cadmium are eaten by tiny animals. Later, these animals are consumed by fish and shellfish, and the food chain continues to be disrupted at all higher levels.

Diseases Eventually, humans are affected by this process as well. People can get diseases such as hepatitis by eating seafood that has been poisoned. In many poor nations, there is always outbreak of cholera and diseases as a result of poor drinking water treatment from contaminated waters.

Destruction of ecosystems Ecosystems (the interaction of living things in a place depending on each other for life) can be severely changed or destroyed by water pollution. Many areas are now being affected by careless human pollution, and this pollution is coming back to hurt humans in many ways.

8.   WAYS TO CONTROL WATER POLLUTION

1. STEPS TO BE TAKEN BY INDIVIDUALS - Never throw rubbish away anyhow. Always look for the correct waste bins. If there is none around, please take it home and put it in your trash can. This includes places like the beach, riverside and water bodies. - Use water wisely. Do not keep the tap running when not in use. Also, you can reduce the amount of water you use in washing and bathing. If we all do this, we can significantly prevent water shortages and reduces the amount of dirty water that needs treatment. - Do not throw chemicals, oils, paints and medicines down the sink drain or the toilet. In many cities, your local environment office can help with the disposal of medicines and chemicals. - Buy more environmentally safe cleaning liquids for the use at home and other public places. - Be mindful not to overuse pesticides and fertilizers. This will reduce runoffs of the material into nearby water sources. - If you live close to a

water body, try to plant lots of trees and flowers around you home so that when it rains, chemicals form your home does not easily drain into the water.

2. STEPS TO BE TAKEN BY GOVERNMENT - Many governments have very strict laws that can help minimize water pollution. These laws are usually directed to industries, hospitals, schools and market areas on how to dispose, treat and manage sewage. - In many developed cities, waste or sewage treatment is very efficient and designed to minimize pollution of water bodies. - There are also lots of organizations and groups that help educate people on the dangers of water pollution. It is always great to join these groups because they regularly encourage other members of their communities to have better attitude towards water.

10.   WAYS TO CONSERVE AND PRESERVE WATER AND ITS QUALITY

• Industries have policies and the technology to achieve their business objectives. At the same time, these policies should also preserve the quality of water.

• A factory that has caused water pollution must be responsible for its actions. It must pay compensation for the damages brought about by its activities.

• Projects such as building hotels and rest houses along beach areas to attract tourists may cause pollution of the seas and beaches. Therefore, a carefully planned construction strategy should be followed.

• To control pests, biological control methods can be used. For example, owls can be used to control rats which eat the oil palm fruit.

• In the agricultural sector, steps should be taken to reduce the use of pesticides, fungicides and fertilizers. These chemicals pollute the water.

• In the education sector, environmental education should be incorporated into the school curriculum. This will make students aware of the water pollution problem. Students will know the effects and consequences of water pollution. They will learn about ways to control this problem.

• Education programmes for the community should be carried out. This increase the public awareness of conserving water, reducing dangerous wastes and recycling to preserve water quality.

• As part of the efforts to preserve water quality, recycling should be carried out. Wastes which can be recycled include old newspapers, glass, aluminium tins, old tyres and plastics.

• Cleaning agents that are used in homes are mostly petrochemical-based. These cleaning agents contain substances that can pollute the rivers and lakes. Today, cleaning agents without petrochemicals are available. The public shoulf be encouraged to use these new cleaning agents.

12.   METHODS OF WATER PURIFICATION

1. FILTRATION a. Filtration removes the suspended solid particles such as clay and sand in the water b. The filtration process can be carried out by using sand particles as the filter. - This system uses layer of fine sand, coarse sand, small stones and pebbles. - The liquid that goes through the filter is called the filtrate and solid material left behind in the filter is called the residue. c. This method of purification does not remove microorganisms and dissolved substances. d. Therefore, filtered water is unsafe for drinking.

2. DISTILLATION a. Distillation of water produces pure water. This water is free from microorganisms, dissolved substances and suspended particles. b. Pure water that is produced through distillation is called distilled water. c. Distilled water is used to prepare chemical solutions in laboratories and liquid medicines in pharmacies. It is also used widely in food industries and as battery water in car batteries.

3. BOILING a. Water from natural sources may contain microorganisms. These microorganisms can cause diseases such as cholera, diarrhoea and typhoid. b. Boiling can kill most of the microorganisms in the water. c. This method can only supply a small amount of water safe for drinking at home. d. However, boiling does not remove suspended particles and dissolved substances in the water.

4. CHLORINATION a. Adding chlorine to water also kills microorganisms in it. b. This method is used to treat large quantities of water. c. The chlorination process is usually used in water purification plants and swimming pools. d. However, too much chlorine in water gives the water an unpleasant smell and is bad for our health.

14.   WHY SHOULD WE SAVE WATER ?

• Water conservation is very important since it will ensure that water supply is finite in the near future. It is also very essential because water is relied on by millions of humans and creatures in the world.

• We should save and conserve our water. Water is essential to all living things. No living person or thing can survive without it. We depend on water for so many things in our lives.

• Saving water normally reduces energy use and cost of pumping and distributing water. It also allows regions to plan for more efficient use of the water resources and ensures availability of water in the future.

• We will never run out of water, but we will deplete the fresh water lakes and rivers and underground aquifers. Then we will only be left with ocean water. Ocean water is very expensive to desalinate. Also, when we use water wisely, we save energy.

15.   HOW DO WE WASTE WATER ?

Here’s a list of things people don’t normally pay attention to, but you should for a more eco-friendly household.

• Dishwasher - Dishwashers can waste so much water if you run it when it is not full. A way to prevent this is to wash your dishes without use of the dishwasher. If you do need to use a dishwasher, make sure it is completely full before you turn it on.

• Brushing Teeth / Washing Dishes WITH the Water Running - Do not keep water running while brushing your teeth / doing the dishes. When you brush your teeth, wet the toothbrush first and turn the water off immediately. Only use the water to rinse. Same for dish washing. Scrub the dishes without the water on, and then turn the water on to rinse off the soap.

• Hot Water - Only use hot water when absolutely necessary. Hot water uses a lot more energy, and it isn’t always necessary.

• Leaky Toilets / Leaky Faucets - If you notice a leaky pipe, faucet, or toilet, get it fixed immediately. A leaky toilet, for example, can waste up to 200 gallons of water a day.

16.   WHAT CAN WE DO TO SAVE WATER ?

• Buy recycled-paper products - Products made from 100 percent recycled paper require much less water in their manufacturing than do those made from virgin paper. If your family goes through four rolls of paper towels a week, choosing recycled reduces waste significantly.

• Water your lawn early in the morning or evening - If you irrigate in the middle of the day, evaporation prevents 14 percent of the water from reaching the plants’ roots. Watering the lawn in the early morning or evening can save the typical home owner 87 gallons a week.

• Uses a lower setting on your dishwasher - Contrary to popular belief, it’s almost never necessary to use the normal setting on a dishwasher or to rinse plates beforehand. The light-wash setting cleans just as well while reducing water use up to 55 percent.

• Install faucet aerators - Faucets account for 15 percent of indoor water use and typically flow at twice the rate they should. Installing aerators in kitchen and bathroom sinks fixes this problem for only a dollar or two per sink.

• Bring your water with you - Buying a daily bottle of water may quench your thirst,