Water pollution can occur when foreign substances make water unsuitable for use by altering its physical, chemical, or biological characteristics. It can be caused by sewage, industrial effluents, agricultural runoff, and other sources. Effects include increased algal growth that reduces dissolved oxygen levels, contamination by toxic chemicals harmful to organisms and humans, and spread of waterborne diseases. Various treatment methods and regulations aim to control water pollution at its sources and minimize its impacts.

2. Water Pollution
 Water pollution can be defined as alteration in
physical, chemical or biological characteristics of
water through natural or human activities making it
unsuitable for its designated use
 It can also be defined as the presence in water of some
foreign substance or impurities ( organic, inorganic,
biological ) in such quantity so as to constitute a
health hazard by lowering the water quality & making
it unfit for use.

3. Physical quality parameter(Physcial
characteristics
 For Drinking water
 Temerature- Biological activity increase with increase
in temperature.
 Temperature of water to be supplied should be
between 10°C to 20°C.
 Temperature more than 25°C is objectionable.
 around 10 degree highly desirable
 Colour - Due to suspended matter – Apparent color
 Due to Dissolved matter _ True colour
 Colour in water due to organic matter, industrial waste
from textile, dyeing, mining refining, pulp and paper ,
iron and manganese oxides..

4.  Coloured water aesthetically not acceptable and can
not be used for various domestic and industrial
purposes.
 Measured by comparing water with standard solution
of platinum cobalt
 Instrument used called tintometer
 For drinking purpose color on platinum cobalt scale
should not exceed 20 & should be preferly less than 10.

5.  Taste & Odour
 Due to presence of dissolve gas like H2S, CH4, CO2,O2
 Dissolve organic matter, algue, mineral salt like NaCl
 Taste imparted by O2 & CO2 is desirable
 Odour Measued in terms of Threshold number
 Turbidity
 Due to suspended particle (fine suspended particle
means colloidal particle & large suspended particle)
 The presence of suspended materials such as clay, silt,
finely divided organic materials, plankton and other
inorganic material in water is known as turbidity.
 Aesthetically displacing due to turbidity
 Disinfection of turbid water can not be done properly

6. Turbid Water

7. Chemical Characteristics
 Total Solids
 Total Soild = Suspended Solid + Total Dissolve Solids
 Suspended solids – Solids retain on filter paper
 Total dissolved solids: Material remaining in the water after
filteration for the suspended solids analysis considered as
dissolved substance. (organic or inorganic)
 Dissolved solids – For drinking water- 500 mg/l desirable
limit
 Chloride
 Present in the water in the form of calcium magnesium &
sodium chloride
 Concentration > 250 mg/l produce noticeable salty taste in
drinking water

8.  Measured by
 Turbidity Rod
 Jackson Turbiditymeter
 Nephlometer
 Baylis Turbiditymeter
 Conductivity
 Relation with TDS
 Higher the TDS , higher the conductivity
 For drinking water conductivity < 2 mhos/cm

9.  Hardness
 Caused by carbonate, bicarbonate, Chloride, Sulphate,
& Nitrate of calicum & Magnesium
 Soft water is testless
 Consume more soap in laundries and form deposit
(boiler scales)
 Temperory Hardness (carbonate Hardness ) &
Permenent Hardness (Non carbonate Hardness)
 Temperory Hardness- carbonate & bicarbonate of
calcium & Magnesium
 Permanent Hardness – Chloride, Sulphate & Nitrate of
Calcium & Magnesium
 Underground water is harder than Surface water

10.  pH
measures of degree of acidity or alkalinity of water.
Potable water pH 6.5 to 8.5
 pH> 7 Alkline
 pH<7 Acidic
 pH = 7 Neutral
 pH considered in biological treatment, disinfection,
Chemical coagulation
 Acidic pH- Corrosion problem
 Alkaline pH – Deposition, incrustation

12.  Alkalinity
 Due to carbonate, bicarbonate & Hydroxide of
calcium & Magnesium
 Phenolphthelin alkalinity due to OH and ½ CO2
 Total alkalinity due to carbonate, bicarbonate &
Hydroxide
 Excess Alkalinity impart better taste to the water,
incrustation problem & interfere in coagulation
 Nitrogen & its Compound
 Organic Nitrogen
 Free amonia
 Nitrite
 Nitrate

13.  If Nitrate> 45 mg/l causes infant disease called
mathemaglobinemia (Blue baby disease)
 Metal and other chemical substances
 Iron and mangenese
 Iron should not > 0.3 ppm
 Manganese should not > 0.05
 Both cause taste, colouration of clothes, incrustation
in water main due to deposition of ferric hydroxide &
manganese Oxide

14.  Flouride
 Should not be less than 0.5 mg/l & greater than 1.5
mg/l
 < 0.5 cause dental caries in teeth of children
 > 1.5 cause Skeleton flourosis as well as spotting &
discoloration of teeth

15. Biological Parameter
 It Include various microorganisms like bacteria, virus,
protozoa, worms present in water. It may be
pathogenic or nonpathogenic
 Coliform group of organism are used as indicator &
there presence can be detected by MPN test or
Membrane filter Technique

16. Sources/Causes of water pollution
 Sources of water pollution can be classified as
 Point sources : Those sources which can be identified
as a single location are called point sources. Examples
of point sources are industrial effluents, power plants,
sewage discharge etc. It is possible to minimize the
water pollution from point sources if the waste water is
collected & is some given some treatment before it is
discharged in to a water body.
 Non point sources which are also called as area or
diffused sources :
 The discharge from this sources is not any particular
site, rather these sources are scattered, which
individually or collectively pollute the water.

17. Sources/Causes of water pollution
 Example of non point sources are surface runoff from
agriculture fields, overflowing small drain, rain water
sweeping roads & fields, atmospheric deposition etc.
 Major sources of water pollution are
 Sewage : discharge of sewer & drains
 Industrial effluents from different industries
 Synthetic detergent used for washing & cleaning
 Agro chemicals like fertilizers containing nitrate &
phosphates & pesticides used in agriculture fields which
comes in the runoff from the agriculture land
 Oil spillage during drilling & shipping
 Waste heat from industrial discharge increase the
temperature of the water bodies
 Major sources of ground water pollution are septik tanks,
deep well injection of industrial effluents, mines etc.

19. water quality index
 A water quality index provides a single number
(like a grade) that expresses overall water quality at
a certain location and time based on several water
quality parameters. The objective of an index is to
turn complex water quality data into information
that is understandable and useable by the
public. This type of index is similar to the index
developed for air quality that shows if it’s a red or
blue air quality day.
 However, a water index based on some very
important parameters can provide a simple
indicator of water quality. It gives the public a
general idea the possible problems with the water
in the region.

20.  Excellent: (WQI Value 95-100)
 Very Good: (WQI Value 89-94)
 Good: (WQI Value 80-88)
 Fair: (WQI Value 65-79)
 Marginal: (WQI Value 45-64)
 Poor: (WQI Value 0-44)

21.  drinking water standard.docx

22. Effects of water pollution
 Phosphorous and Nitrate from fertilizers & detergent
contaminate surface water where they act as nutrients
& promote the growth of oxygen consuming algae
which reduce the D.O. level of water , killing the fish &
other aquatic organism
 Industrial effluent results in the addition of poisonous
chemicals such as Arsenic, Mercury, Chromium, Lead
etc. which kill aquatic organisms & may reach human
body through contaminated food. (i.e. fish)
 Domestic, commercial & industrial effluents
(Petroleum refineries, paper mills, breweries,
tanneries, slaughter houses) contaminate the water
with organic pollutant

23. Effects of water pollution
 This organic matter provide nutrition for micro-
organisms which decompose the organic matter &
consume oxygen & reduce the DO level of the
ecosystem thereby killing the aquatic organisms.
 Non biodegradable pesticides (especially
organochlorine) travel through food chain &
ultimately reach humans where they accumulate in
fatty tissue & affect the nervous system.
 Water borne disease like typhoid, cholera, , bacillary,
dysentry, cholera are prominent health hazards arising
from drinking contaminated water

24. Effects of water pollution
 Flouride containing pollutants cause florosis
 Thermal pollution of water reduce s the DO level of
the aquatic system making it incapable of supporting
life.
 Oil pollutants have been known to be responsible for
the death of many water birds & fishes.
 Concentration of Nitrate more than 45 mg/l cause blue
baby diseases in infants
 A disease called minamata occurs due to mercury
contaminated fish

25. Control of water pollution
 Water pollution can be reduced by the following
measures
 By proper sewage treatment before discharging in to
water bodies
 Industrial effluent should be proper treated before
releasing them in to water
 By enforcing stringent laws for the disposal of sewage
& industrial waste in to water body
 Washing of cloths & taking bath directly in river lake
which supply drinking water should be prohibited

26. Control of water pollution
 Pesticides & fertilizers should be judiciously used to
reduce the chemical pollution due to surface runoff
from farms. Less stable pesticides should be used.
 Increasing the vegetation cover to reduce the water
pollution due to soil erosion
 Encouraging reuse of water
 To avoid the thermal pollution hot water should be
cooled before releasing it in to water bodies
 Advance treatment for removal of nitrates &
phosphates should be adopted to prevent
eutrophication

27. Waste water treatment process(Sewage
treatment process)
 Preliminary Treatment :
 Screening: removes big, floating solid particles such as
wood, garbage, dead animals etc.
 Grit chamber: remove heavy solid particles such as sand
and gravel
 Primary treatment : for the removal of suspended
particles
 Primary Sedimentation tank (PST): wastewater kept for
6-8 hours so that 50-70% solids removed
 PST removes 60% suspended solids
 30% oxygen demanding waste
 20% Nitrogen compounds
 10% Phosphorous

28. Waste water treatment process

29.  Secondary treatment- for the removal of dissolved
organic matter
 Organic matter remove up to 80-90 %

30.  This word is originated from Greek word ‘eu’- well and
‘trophes’- food. Thus means ‘well feed’ or ‘nutrient
rich’.
 Eutrophication is defines as excessive nutrient load in
water bodies.
EUTROPHICATION

31.  Process of eutrophication
Nutrient
Enrichment
Growth of
green plants
(algae)
Death of
green plants
Decay of
dead plants
and growth
of bacteria
Depletion of
DO
Death of
organisms

32. Eutrophication of lake
 The industrial wastes, municipal waste water, runoff
from agricultural lands provide plenty of phosphates,
nitrates and various minerals stimulating algal growth.
Due to which the water body become green.
 In due course of time the algal bloom may die abruptly.
 The decaying organic matter causes depletion of DO ,
destroying fish and other aqautic species
 Bad taste, bad odour is produced and turbidity
increase which reduce the acceptability of water as a
domestic sources

33. Control of Eutrophication
 The main anthropogenic source of phosphorous are
agricultural runoff (due to use of phosphorous
fertilizer) and domestic sewage
 In sewage source of phosphorous is the human faces
and detergents. Human feces can not be restricted but
use of phosphorous in detergent can be restricted

34.  The other steps to control eutrophication are recycling
of nutrients through harvest, removal of algue blooms
by degrading, applying alguecides like copper
sulphate, chlorine etc on water bodies
 The use of fertilizer in the drainage area should be
controlled to reduce the entry of phosphorous through
surface runoff flowing over such fields and finally
entering in the lake.
 It can also be reduced by applying the methods to
reduce soil erosion

35. Story of flouride contamination
 the story of flouride very final - Copy.docx

36. Marine Pollution
 Marine pollution can be defined as the introduction of
substances to the marine environment directly or
indirectly by humans, resulting in the adverse effects
such as hazard to human health, obstruction of
marine activities & lowering the quality of sea water
 Pollutant can enter the sea directly from the outfalls
and sometimes from coastal towns, but most
frequently they enter from esturies

37. Causes or sources of Marine pollution
 The most obvious input is through pipes/outfall
directly discharging waste in to sea. Sewage from
residences and hotels in coastal towns are directly
discharged in the sea.
 Off shore oil exploration & extraction also pollute the
seawater to a large extent
 Ship accidents & accidental spillage of oil, other
material at sea can be very damaging to the marine
environment.
 Pesticides & fertilizers from agriculture which are
washed off the land by rain enter water courses (rivers,
streams) and eventually reach the sea.

38.  Petroleum and oil washed off from roads normally
enter the sewage system but storm water overflow
carry these materials in to river and eventually in to
seas.

39. Effects of Marine pollution
 Disposal of large amount of organic waste in to sea
causes phytoplankton blooms
 Oil spill/slicks have damaging impacts on marine &
bird species.
 It also effects mangrove swamps which tends to trap oil
, affecting their flowering, fruiting and germination
 It causes clogging of gill of marine species. This further
has impact on commercially important marine species,
reducing the market value of sea food.
 Contaminated sea water imparts an unpleasant flavour
to the fish and sea food and is detectable even at
extremely low levels of contamination. Thus there
would be significant economic loss to the sea food
industry.

40. Control of Marine pollution
 Sewage should be given complete treatment before
disposing it in to the sea.
 Toxic pollutants from the industries should not be
discharged in to the sea.
 Dumping of toxic, hazardous waste and sewage sludge
should be banned
 Oil ballast should not be dumped in to sea
 Development activities on the coastal area should be
minimized
 Runoff from the non-point sources should be prevented to
reach coastal area.
 Ecologically sensitive coastal area should be protected by
not allowing drilling