Water Pollution

What is water pollution?

Water pollution is the contamination of water bodies (e.g. lakes, rivers, oceans, aquifers and groundwater), very often by human activities.
 
Any change or modification in the physical, chemical and biological properties of water that will have a detrimental consequence on living things is water pollution.

Types of water pollution
There are many types of water pollution because water comes from many sources. Here are a few types of water pollution:

1. Nutrients Pollution
Some wastewater, fertilizers and sewage contain high levels of nutrients. If they end up in water bodies, they encourage algae and weed growth in the water. This will make the water undrinkable, and even clog filters.

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 mixing physically with the water can be called surface water pollution.

3. Oxygen Depleting Water bodies have micro-organisms. These include aerobic and anaerobic organisms. When to 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 deep into the ground by rain water. This gets to underground water, causing pollution underground.

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.

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 farmers 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, make them infertile and kill them.

8. Oil Spillage
Oil spills usually have only a localized affect on wildlife but can spread for miles. The oil can cause the death of many fish and stick to the feathers of seabirds causing them to lose the ability to fly.
            

 

Causes of water pollution
 

Sewage and waste water

Everyday, we cook, do laundry, flush the toilet, wash our cars, shower and do many things that use water. Think about how we use water in schools, hospitals and public places.

Where do you think all the water, liquid waste, toilet and urine ends up? In many developed communities, this waste water and soluble waste (called sewage) is treated, cleaned and dumped into the sea. Even though they are treated, they are never the same as fresh water.
Click this red button to see how sewage is treated:

Septic Tanks
Every domestic (home) toilet is connected to septic tank usually located outside the house. Each time poop is flushed down the toilet, it goes into this tank, where the solid part is separated from the liquid part. Biological processes are used to break down the solids and the liquid is usually drained out into a land drainage system. From this stage, it can escape into the soil and nearby water bodies.


Ocean and marine dumping Paper waste, food waste, plastic, rubber, metallic and aluminum waste. In some countries, there are deposited into the sea. All these waste types take time to decompose. 

.

Underground storage and tube leakages
Many liquid products (petroleum products) are stored in metal and steel tubes underground. Other sewage systems run in underground tubes. Overtime, they rust and begin to leak. If that happens, they contaminate the soils and the liquids in them end up in many nearby water bodies.

 
Atmospheric
Atmospheric deposition is the pollution of water bodies caused by air pollution. Each time the air is polluted with sulphur dioxide and nitrogen oxide, they mix with water particles in the air and form a toxic substance. This falls as acid rain to the ground, and gets washed into water bodies.

Effects of water pollution. 

 

The effects of water pollution are varied and depend on what chemicals are dumped and in which locations:

Many water bodies near urban areas (cities and towns) are highly polluted. This is the result of both garbage dumped by individuals and dangerous chemicals legally or illegally dumped by manufacturing industries, health centers, schools and market places.

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. 

 Prevention of water pollution

Dealing with water pollution is something that everyone (including governments and local councils) needs to get involved with. Here are a few things you can do to help. Learning about the issue (like you are doing) is the greatest and most important step to take. Here are a few more:

 

You can help

Never throw rubbish away anyhow. Always look for the correct waste bin. 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. Check with your local authorities if there is a chemical disposal plan for local residents.

Buy more environmentally safe cleaning liquids for the use at home and other public places. They are less dangerous to the environment.

If you use chemicals and pesticides for your gardens and farms, be mindful not to overuse pesticides and fertilizers. This will reduce runoffs of the material into nearby water sources. Start looking at options of composting and using organic manure instead.

If you live close to a water body, try to plants lots of trees and flowers around your home, so that when it rains, chemicals from your home does not easily drain into the water.

   

Governments, local councils and laws
Many governments have very strict laws that 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 minimise pollution of water bodies.

 
Practice Exercise:

Q1. Which is the main water polluting material?
a.plastic
b.cloth
c.Oil spill

Q2. Name the gas releasing from the Marshy areas? a. Oxygen
b. Nitrogen
c. Methane

Q3. The underground water is mainly polluted due to ______________
a. entering of polluted water to the water table
b. the construction of polluted water
c. the construction of well.
 
Answers:
1. c 2. c 3. a