3. Water pollution is the contamination of water bodies
(e.g. lakes, rivers, oceans, aquifers and groundwater). This
form of environmental degradation occurs when pollutants
are directly or indirectly discharged into water bodies without
adequate treatment to remove harmful compounds.
4. Water pollution affects the entire
biosphere – plants and organisms
living in these bodies of water.
In almost all cases the effect is
damaging not only to individual
and population, but
also to the natural
5. WATER ;A SCARCE NATURAL
Water scarcity is the lack
of sufficient available water
resources to meet water needs
within a region.
It affects every continent and
around 2.8 billion people
around the world at least
one month out of every year.
More than 1.2 billion people
lack access to clean drinking
6. Water scarcity involves water shortage, water
stress or deficits, and water crisis
More than one in every six people in the world is
water stressed, meaning that they do not have
access to potable water.
a country or region is said to experience "water
stress" when annual water supplies drop below
1,700 cubic metres per person per year.
Surface water pollution
found on the exterior of
the earth’s crust, oceans,rivers and
Ground water pollution
found in soil or under rock structure or
10. Oxygen depletion pollution
microorganisms that in water and
feeds on biodegradable substances
Sources of surface water pollution are
generally grouped into two categories
based on their origin.
Non point source
13. Point source
Point source water pollution refers
to contaminants that enter a
waterway from a single,
identifiable source, such as
a pipe or ditch.
discharges from a sewage
treatment plant, a factory, or a
city storm drain.
The CWA definition of point source
was amended in 1987 to include
municipal storm sewer systems, as
well as industrial storm water, such
as from construction sites.
14. Non point source
Nonpoint source pollution refers to
diffuse contamination that does not
originate from a single discrete source.
NPS pollution is often the cumulative
effect of small amounts of
contaminants gathered from a large
leaching out of nitrogen compounds
from fertilized agricultural lands.
Nutrient runoff in storm water from
"sheet flow" over an agricultural field or
a forest are also cited as examples of
Contaminated storm water washed off
of parking lots, roads and highways,
called urban runoff, is sometimes
15. Major sources
1. Industrial waste:
contains toxic chemicals and
pollutants which can cause air
pollution and damage to us and
lead, mercury, sulphur, asbestos,
nitrates and many other harmful
Many industries do not have
proper waste management system
and drain the waste in the fresh
water which goes into rivers,
canals and later in to sea.
change the color of water,
increase the amount of minerals,
also known as Eutrophication,
change the temperature of water
and cause serious hazard to water
16. 2. Sewage and waste water:
The sewage and waste water that is produced
by each household is chemically treated and
released in to sea with fresh water.
carries harmful bacteria and chemicals that can
cause serious health problems.
Microorganisms in water are known to be causes
of some very deadly diseases and become the
breeding grounds for other creatures that act like
carriers. These carriers inflict these diseases via
various forms of contact onto an individual eg:
17. 3. Mining activities:
Mining is the process of crushing the rock and
extracting coal and other minerals from
These elements when extracted in the raw form
contains harmful chemicals and can increase the
amount of toxic elements when mixed up with
water which may result in health problems.
Mining activities emit several metal waste and
sulphides from the rocks and is harmful for the
18. 4. Marine dumping:
The garbage produce by
each household in the
form of paper, aluminum,
rubber, glass, plastic, food
is collected and deposited
into the sea in some
These items take from 2
weeks to 200 years to
When such items enters
the sea, they not only
cause water pollution but
also harm animals in the
19. 5. Accidental Oil leakage:
Oil spill pose a huge concern as large amount of
oil enters into the sea and does not dissolve with
water; there by opens problem for local marine
wildlife such as fish, birds and sea otters. For e.g.:
a ship carrying large quantity of oil may spill oil if
met with an accident and can cause varying
damage to species in the ocean depending on the
quantity of oil spill, size of ocean, toxicity of
20. 6. Chemical fertilizers
Chemical fertilizers and
pesticides are used by
farmers to protect crops
from insects and
when these chemicals
are mixed up with water
produce harmful for
plants and animals.
Also, when it rains, the
chemicals mixes up with
rainwater and flow down
into rivers and canals
which pose serious
damages for aquatic
21. 7. Global warming:
An increase in earth’s temperature due
to greenhouse effect results in global
warming. It increases the water
temperature and result in death of
aquatic animals and marine species
which later results in water pollution.
22. 8. Radioactive waste:
The element that is used in production of nuclear
energy is Uranium which is highly toxic chemical.
The nuclear waste that is produced by radioactive
material needs to be disposed off to prevent any
Nuclear waste can have serious environmental
hazards if not disposed off properly.
Few major accidents have already taken place in
Russia and Japan.
23. 9. Urban development: As population has
grown, so has the demand for housing, food and
cloth. As more cities and towns are developed,
they have resulted in increase use of fertilizers to
produce more food, soil erosion due
to deforestation, increase in construction
activities, inadequate sewer collection and
treatment, landfills as more garbage is produced,
increase in chemicals from industries to produce
24. 10. Underground storage
leakage: Transportation of coal and other
petroleum products through underground
pipes is well known. Accidentals leakage
may happen anytime and may cause
damage to environment and result in soil
25. Water pollutants also include both
organic and inorganic factors.
Organic factors include volatile
organic compounds, fuels, waste from
trees, plants etc.
Inorganic factors include ammonia,
chemical waste from factories,
discarded cosmetics etc.
26. Measurement of water pollution
Water Pollution can be measure through the various
broad categories. It can be defined into three major
Physical: It includes the measurement of water
temperature, turbidity, total suspended particle in the
Chemical: It includes the measurement of pH value,
Chemical Oxygen Demand(COD) and Biological
Oxygen Demand(BOD). There are some other
factors which also falls under this categories like oil,
nutrients and metal present in the water sample.
Biological: It includes the presence of Microbes in
the water, the total nutrients aquatic lives are getting
from the water. Water pollution can also be
measured by the aquatic habitat present in the water
27. BOD basically involves the
measurement of dissolved
oxygen (DO) utilized by the
microorganisms for the
biochemical oxidation of
organic matter. The demand
for oxygen and the process
of oxidation depends on the
type and quantity of organic
matter, temperature and type
of the organism used.
28. Chemical oxygen demand refers to
the oxygen equivalents of organic
matter that can be oxidized by using
strong chemical oxidizing agents.
Usually, potassium dichromate in the
presence of a catalyst, in acidic
medium is employed for this purpose.
30. Effect on humans
Diseases caused by :
drinking contaminated water
Swimming in polluted water
Contact with chemically polluted water
31. Effect on animals
200 turtles in Australia’s surround
water die each year
Birds and mammals become coated
32. Control measures
Administration of water pollution
control should be in the hands of
state or central government.
Scientific techniques should be adopted
for environmental control of catchment
areas of rivers, ponds or streams.
Industrial plants should be based on
recycling operations as it helps prevent
disposal of wastes into natural waters but
also extraction of products from waste.
Plants, trees and forests control pollution
as they act as natural air conditioners.
Trees are capable of reducing sulphur
dioxide and nitric oxide pollutants and
hence more trees should be planted.
33. Control measures
No type of waste (treated, partially treated
or untreated) should be discharged into any
natural water body. Industries should
develop closed loop water supply schemes
and domestic sewage must be used for
Qualified and experienced people must be
consulted from time to time for effective
control of water pollution.
Public awareness must be initiated
regarding adverse effects of water pollution
using the media.
Laws, standards and practices should be
established to prevent water pollution and
these laws should be modified from time to
time based on current requirements and
Basic and applied research in public health