Water pollution occurs when harmful substances are directly or indirectly discharged into water bodies. There are three main types of water pollution: surface water, ground water, and salty water pollution. Water pollution has negative effects like making water unfit for drinking and causing diseases. Various methods can purify water, like filtration, sedimentation, and distillation. The main causes of water pollution are untreated industrial and domestic waste, and agricultural runoff. Preventing water pollution requires treating waste before discharge and following pollution control rules.

1. WATER
POLLUTION
BY: Chhavi Kumawat

2. CONTENT
• Definition
• Types of water pollution
• Prevention of water pollution
• Potable water
• Purification of water
• Various method to purify water
• Causes 0f water pollution
• Effects of water pollution

3. DEFINATION
Water pollution is the contamination of water bodies
(e.g.) lakes, rivers, oceans, and groundwater).Water
pollution occurs when pollutants are directly or indirectly
discharged in to water bodies without adequate treatment
to remove harmful compounds.

4. TYPES OF WATER POLLUTION
Water is one of the most abundant compounds on
Earth. About 75% of the Earth’s surface is
covered with water.The three main types of
water sources are -:
• Surface water
• Ground water
• Salty water
Unfortunately, we have been constantly
polluting our rivers, seas, and other water
bodies.

5. EFFECTS OF WATER POLLUTION 1
• Industrial wastes discharged into the waters contain a
lot of toxic substances that make water unfit for
drinking and bathing.
• Untreated domestic sewage, when released into water
bodies, becomes a breeding ground for a number of
organisms that cause water-borne diseases.
• Oil spills are very harmful to aquatic animals, and lead
to destruction of marine life.The cleaning up process
also causes a lot of damage to marine habitat.
• Pollution of water also leads to a reduction in the
number of aquatic plants and animals due to
destruction of habitat and nesting places.

6. EFFECTS OF WATER POLLUTION

7. PREVENTION OF WATER
POLLUTION
Some steps to prevent water pollution are-:
1. Bathing and washing clothes near water bodies such
as lakes, ponds, and rivers should be avoided.
2. Domestic and industrial sewage wastes should be
treated to remove toxic substances before being
released into water bodies.
3. Pollution-control rules enforced by the government
should be followed strictly.
4. Use of eco-friendly fertilizers and herbicides should
be encouraged.

8. POTABLE WATER
• The water suitable for drinking by human beings
is called potable water.To be considered fit for
human consumption, a sample of water should
• Be transparent, colorless, and odorless,
• Contain sufficient amount of dissolved oxygen
and salts, and
• Be free from harmful chemicals and
microorganisms.

9. POTABLE WATER

10. PURIFICATION OF WATER 1
Water supplied in our homes generally comes from
river and is contaminated with suspended impurities
like sand, silt, and clay; soluble impurities like salts;
and also microorganisms.Water, therefore, has to be
cleaned in big purification plants before it reaches our
homes.The three main processes that water
undergoes during purification are sedimentation,
filtration, and chlorination .

11. PURIFICATION WATER 2
The various processes employed in purification of water are
• Water collected from river is made free of large pieces of
dirt and pumped into reservoirs.
• Water is allowed to stand in large tanks so that suspended
impurities settle down.This process is called sedimentation.
• Water is passed through filter beds to remove all other
insoluble impurities.This process is called filtration.
• Water is chlorinated (by addition of chlorine) to kill any
harmful microbes that may be present in at this stage.
• Water is supplied to homes and factories by huge water
mains.

12. PURIFICATION OF WATER

13. VAIROUS METHOD TO PURIFY
WATER:
Filtration – The process of removal of insoluble impurities by
passing impure water through a filter paper is called filtration.
Sedimentation and decantation – In this method, impure
water is allowed to stand undisturbed in a container, which
allows insoluble impurities such as mud to settle to the
bottom as sediments.This process is called sedimentation.
Clean water can thereafter be transferred into a clean
container by the process of decantation.
Distillation – In this method, impure water is first heated to its
boiling point to convert water into steam.The impurities are
left behind in the container.The steam is then passed through
a condenser, where it cools and changes back into liquid
water.

14. VIROUS METHOD TO PURIFY
WATER:

15. CAUSES OF WATER
POLLUTION
The main causes of water pollution are -:
• Discharge of untreated industrial and domestic
sewage in to water bodies.
• Bathing animals, washing clothes, etc., in or near
lakes, rivers, etc., dirties these water bodies.
• Oil leaks from ferry boats and ships leave a trail
of oil on the water surface and pollute rivers and
oceans.
• Inorganic pesticides and chemical fertilizers used
by farmers drain into water bodies by a process
called leaching. As a result, certain pesticides
such as DDT can enter the bodies of aquatic
animals and eventually reach human beings by
the way of food chains.

16. CAUSES OF WATER
POLLUTION

17. EFFECTS OF WATER POLLUTION 1
• Industrial wastes discharged into the waters contain a
lot of toxic substances that make water unfit for
drinking and bathing.
• Untreated domestic sewage, when released into water
bodies, becomes a breeding ground for a number of
organisms that cause water-borne diseases.
• Oil spills are very harmful to aquatic animals, and lead
to destruction of marine life.The cleaning up process
also causes a lot of damage to marine habitat.
• Pollution of water also leads to a reduction in the
number of aquatic plants and animals due to
destruction of habitat and nesting places.

18. EFFECTS OF WATER POLLUTION 2
• Ignition of arms and weapons releases large amounts
of mercury. When water contaminated with mercury
is used for drinking by animals and human beings, it
causes numbness of limbs, lips, and tongue. It can also
lead to blurred vision and mental disorders.
• The waste water released by factories and industries
and the fertilizer-rich runoffs from agricultural fields is
rich in organic matter. The process of washing away of
fertilizers into water bodies is called leaching. The
entry of nutrient-rich water results in a thick growth
of algae, called algal bloom, and many other weeds.
Soon these plants cover the entire surface of water.
This is called eutrophication.