2. Some basic information about
• The water is a chemical substance with the
• The water is very important for life , because it
is vital. The animals or humans drink water
because the body needs 75% water to exercise
for example : walking
• Water covers 70% of Earth, that is two third
parts of Earth
3. Sources of water
• Rain Water
• Sea Water
• River Water
• Lake Water
• Underground Water
Don’t misuse the water
extracting methods !!
4. Some uses of water
ii. For Drinking
5. • any kind of contamination of bodies of water such as
rivers, lakes or wetlands with substances that can pose
threats to human health or the natural environment.
• Such pollution is a major source of death and disease
worldwide, especially in developing nations.
6. Specifications of Domestic Water
• Should be colorless and odourless
• Good in taste
• Should not be hot
• Turbidity should be less than 10 ppm
• Free from objectionable dissolved gases like H2S
• Free from As, Cr, Mn salts
• Alkalinity should not be high pH- 7.0-8.5
• Reasonably soft, total hardness should be less than 500 ppm
• Free from disease producing microorganisms
• Chloride, fluoride and sulphate contents should be less than 250
ppm, 1.5 ppm and 250 ppm respectively
7. Wastage of water in our daily life!!!!
• 1. LEAKY TAPS AND FAUCETS
• 2. FLUSHING
• 3. WASHING THE CAR
• 4. BATHING
8. Water Pollution
Water pollution is the contamination of water bodies (e.g. lakes,
rivers, oceans, aquifers and groundwater), very often by human
It occurs when pollutants (particles, chemicals or substances that
make water contaminated) are discharged directly or indirectly into
water bodies without enough treatment to get rid of harmful
9. Noticeable signs of Water Pollution
• Odours from rivers, streams, lakes and ocean beaches
• Oily and greasy materials floating on surface of water
• Unchecked growth of aquatic weeds in water bodies
• Bad taste of drinking water
• Decrease of aquatic life etc.
10. Types of water pollution
Surface water:- Water resources like huge oceans, lakes, and rivers etc.
are called surface waters.
Contaminants such as chemicals, nutrients, and heavy metals are
carried from farms, factories, and cities into streams and rivers and
then to seas and oceans.
Our seas are also sometimes spoiled by oil spills.
Ground water:- Water stored underground in aquifers is known as
Groundwater gets polluted when contaminants (pesticides, fertilizers)
or waste leached from landfills and septic systems make their way into
an aquifer, rendering it unsafe for human use.
It is virtually impossible to remove contaminants from groundwater.
Groundwater can also spread contamination into streams, lakes, and
11. Point source: When contamination originates from a single source
such as a pipe, such as a discharge pipe attached to a factory.
Nonpoint source: When contamination is derived from diffuse
sources. This type of pollution is often the cumulative effect of small
amounts of contaminants gathered from a large area. These may include
agricultural runoff or debris from land into waterways.
Transboundary: When contaminated water from one country enters
into waters of another country e.g. radioactive waste from reprocessing
plant in England is carried by the Gulf Stream to
the Norwegian coast; traces of PCBs have even been found in birds and
fish in the Arctic. They were carried there through the oceans,
thousands of miles from where they originally entered the environment.
Sources of Water Pollution
12. Sources of Water Pollution
The main sources of water pollution are natural, agricultural, mining,
municipal, industrial and accidental:
a) Natural pollution:-
• Aerial contaminants entering the water body due to rainfall or melting
• Decaying of plants, animals and organic matter.
• Leachates from animal excreta.
b) Agricultural pollution:-
• Soil and silt washings from land surfaces.
• Fertilisers, insecticides, pesticides and weed killers.
13. • c) Mining pollution:-
• Tailings from ore washing
• Inert suspended solids
• Soluble toxic materials
• Acid drainage
• Sewage obtained from domestic premises, institutions, commercial
and industrial buildings.
e) Industrial pollution:-
• Effluents coming from various industries
14. Point sources
• Those sources which can be readily
identified at a single location.
• For instance- industrial, municipal sewage
,treatment plants, combined sewer overflow,
raw sewage discharges, etc.
• This type of discharge can be controlled.
• Those sources whose location cannot be
• For instance- run off from agriculture lands,
forestry, mining, construction, etc.
• This cannot be easily controlled.
Sources of water pollution :-
16. Effects of Water Pollution
The adverse effects of water pollution can be studied under the following heads:-
i. Physical effects
ii. Oxidation effects
iii. Toxic chemical effects
iv. Chemical nutrient effects
v. Micro-organism effects
vi. Radionuclide effects
• Due to suspended particle solids, cooling water from power stations and oily surface films.
• Solids may be inert material wastes or insoluble finely divided organic solids.
1. Inert materials in water slowly accumulate on vegetation foliage, and produce a deposit on
—These may cause reduction in solar energy absorption thereby decreasing rate of
photosynthesis causing low oxygen conditions on the river bed.
—Suspended materials may also cause turbidity .
2. Finely divided organic solids will be biodegraded and will cause reduction of the dissolved
oxygen in water.
18. • Cooling water from power stations can cause a rise in water temperature
and brings about a thermal pollution.
• Variations in temperature will affect the metabolic rate of physiological
• At higher temperatures blue green algae and sewage fungus will grow
more which will result in plant death.
• The oxygen saturation percentage will be reduced and biodegradation will
• Both these factors will cause oxygen deficiency in water.
19. • Waste oil, fats and grease can enter from several sources.
• These will form a thin film on the water surface which prevents the exchange of oxygen
with the atmosphere causing reduction of water oxygen saturation.
• Spillage from oil tankers in sea will cause marine pollution and shore contamination.
• Oil slicks are responsible for the death of many birds.
There are two types of oxidation namely:
a) Oxidation by action of bacteria upon organic pollutants.
b) Chemical oxidation of other pollutants.
• Both type of oxidation involves the use of dissolved oxygen.
• It will cause increase in Biological Oxygen Demand (BOD) .
• Causes deficiency of oxygen in water.
• Bacterial Oxidation-
• Chemical oxidation-
21. iii. Toxic
• Some organic and inorganic chemical
substances are toxic to plant, animals
• Chemical toxic substances can be
broadly classified as metals and salts,
pesticides, acids and alkalies etc.
• Pesticide pollutions produce harmful
effect over the body.
• Acids and alkalies may change the
Ph value of water .Changes in ph
value may affect physiological
processes and actions of toxins.
• Chemical nutrients are required by plants and animals for maintaining their growth and
• Nitrates and phosphates occur in water in small quantities.
• The nutrient levels slowly rise as a result of bio-degradation of dead organic material.
This rise in nutrients is called ageing or eutrophication.
• Increased concentration of nitrates and phosphates in water produce the overall effects
of an increase in the rate of growth of plants and animals.
Unicellular green and blue green algae and blanket weed reduce light
penetration and restrict reoxygenation of water.
• It will cause adverse conditions for river and canal navigation, and for swimming,
bathing and fishing.
• Nitrates are taken into body by food and drink and excess will cause blood diseases
and gastric cancer.
• Wastes that are discharged into
water contain pathogenic
organisms that are capable of
transmitting human diseases.
• Bacteria are responsible for
cholera, typhoid fever, bacillary
• Virus may cause poliomyelitis,
infective hepatitis, and echo and
• Round worm beef and pork tape
worms may also cause diseases.
25. vi. Radio-
• Solid waste(nuclear) filed in containers is dumped into sea bed.
• The corrosive action of sea water my cause leakage of radioactive waste in water and
it may pose health hazards.
• Radionuclides can enter the human body through dusts and aerosols and can also be
absorbed by plants and animals.
• The condition of excessive growth of plants in a water body is called
• It is natural process of aging of water body.
• It is a result of very slow process of natural sedimentation of microscopic
organisms which takes geologic times to complete.
• The completion of the process results in the extinction of the water body.
• The process is propelled by increasing concentrations of nutrients
necessary for biological activity.
• Causes decreased D.O( dissolved oxygen), increased B.O.D, and
emission of foul gases.
27. Classification of Water Pollutant
The various types of water pollutants can be broadly classified into
4.Suspended solids and sediments
28. Organic Pollutant
The organic compounds may further be
categorised as follows
• Natural organic pollutant
• Sewage and industrial effluents
• Synthetic organic contaminants
• Microbiological components
29. Natural Organic Pollutant
• Natural organic contaminants in water come from the
breakdown of naturally occurring organic materials like decay
of leaves, plants ,dead animals etc.
• Many plants and micro organisms release organic matter in to
a water body through their metabolic processes.
• Various types of algae and vegetation flourishing in a lake or
reservoir can also be a source of objectionable organic
compounds in water.
30. Sewage and Industrial Effluents
• Organic pollutants are also discharged as municipal sewage and industrial
effluents (such as food processing units,paper mills,etc .)
31. Synthetic Organic Components
• These are man made materials which may enter the water bodies along
with sewage and other wastes.
• Synthetic organic components includes both volatile organic chemicals and
synthetic organic chemicals.
• Most common organic pollutant in VOC are industrial solvents , such as
carbon tetrachloride(used as fire extinguisher and cleaning agent).
• Most common organic pollutant in SOC are pesticides and herbicides.
• Presently , the most controversial organic pollutant are polychlorinated
biphenyls and dioxin, which are very toxic and known to cause caner even
at very low concentration.
32. Micro-biological Pollutants
• Many different micro organisms such protozoa
,viruses , bacteria are found in polluted water.
• Most of these do not pose a health hazard to
• The organisms that can cause sickness In
human are called pathogenic organisms.
33. Inorganic Pollutant
• Apart from the organic matter discharged in the water body through
sewage and industrial wastes high concentration of heavy metals
and other inorganic pollutants contaminates the water.
• The accumulation of heavy metals may have adverse effect on
aquatic flora and fauna and may constitute a public health
problem where contaminated organisms are used for food.
• Algal growth due to nitrogen and phosphorous compounds can be
observed . Metals in high concentration can be toxic to biota.
34. Radioactive Pollutant
• Radioactive material orginates from the following:
• Mining and processing of ores.
• Radioactive discharge from nuclear power plants and nuclear reactors.
• Uses and testing of nuclear weapons.
Suspended Solids And Sediments
• Comprises of silt ,sand , and minerals eroded from land.
• Appears in the water through surface runoff during rainy season and
through municipal sewers.
• This can lead to the siltation , reduces storage capacities of
• Deposition of solids in the quiescent stretches of the stream and
ocean bottom can affect normal aquatic life and affect the diversity of
37. Common Water-Borne Diseases
• Water-borne diseases are caused by pathogenic organisms carried by water
containing faecal or sewage contamination.
• a) Bacterial Diseases
• 1. Typhoid fever:-
• Typhoid fever is the most important endemic and epidemic water borne
disease of regions where supplies are drawn from surface sources
contaminated by human faeces or urine.
• This is caused by the bacterium salmonella typhi.
38. 2.Paratyphoid fever:-
• Mostly due to ingestion of contaminated food, specially milk, dried or frozen eggs and other
• This is caused by bacterium Salmonella paratphiA, B or C.
• Number and infectivity of organisms released to environment are generally smaller than the
• This is caused by the bacterium vibrio cholerae.
• Usually the infection is contracted by ingestion of water contaminated by infected human
• Sometimes it may be contracted by contaminated food or personal contact.
• Cholera is much more violent in its onset and often more fulminating in its clinical course.
39. 4.Bacillary dysentery:-
• Bacillary dysentery is an intestinal infection caused by a group of Shigella
• Which can be found in the human gut.
• Infection by Shigella may be asymptomatic or only cause mild illness.
• This disease is mostly contracted due to ingestion of food
contaminated by flies or by unhygienic food handlers.
• It may sometimes be contracted by consuming water contaminated by
b) Protozoal Diseases:-
• The 2 important diseases that come under this category are:
• Amoebiasis and amoebic dysentery.
• These are caused by the protozoon entamoeba histolytica.
• They live in the human large intestine forming cyst which are
excreted in the bowel discharges of infected persons and
which will live for long periods in water.
• Infection takes place due to ingestion of these cysts which are
carried by water or flies or even human fingers.
41. c) Virus Diseases:-
Viral diseases are extremely widespread infections caused by viruses, a type of microorganism.
The most common type of viral disease is the common cold, which is caused by a viral infection of the upper
respiratory tract (nose and throat).
Other common viral diseases include:
Human immunodeficiency virus (HIV/AIDS)
Mumps, measles and rubella
42. d) Helminthic (worm) disease:-
Helminthiasis, also known as worm infection, is any macroparasitic disease of humans and
other animals in which a part of the body is infected with parasitic worms, known as
There are numerous species of these parasites, like tapeworms, flukes, and roundworms.
Worm infections are sporadic and occur only under grossly insanitary conditions or
through gross mismanagement of sewage disposal system.
The most common helminthiases are those caused by infection with intestinal
helminths, ascariasis, hookworm etc.
43. Related legislation
• Water act 1976
The act was enacted in 1974 with the objective to provide for the
• prevention and control of water pollution and for the maintaining or
• restoring of wholesomeness of water in the country.
It provides for the establishment of central state and joint pollution
• control boards for the prevention and control of water pollution and
• defines their powers and responsibilities.
44. The Water(Prevention and Control of Pollution) Cess Act 1977
• The Water(Prevention and Control of Pollution)
Cess Act was enacted in 1977, to provide for the
levy and collection of cess on water consumed by
persons operating and carrying on certain types of
industrial activities. This cess was meant to collect
with a view of argument the resources of the
Central Board and the State Boards for the
prevention and control of water pollution.
45. Environment (Protection) Act 1986
Environment (Protection) Act 1986 provides for the
protection and improvement of environment and
the matters associated with it.