1. Dr Fayaz A. Malla
Assistant Professor
HED, Govt. of J&K
2. 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. Point and Nonpoint Sources
NONPOINT SOURCES
Urban streets
Suburban development
Wastewater treatment
plant
Rural homes
Cropland
Factory
Animal feedlot
POINT SOURCES
6. Major Categories
of Water
Pollutants
INFECTIOUS AGENTS
• Examples: Bacteria, viruses, protozoa, and
parasitic worms
• Major Human Sources: Human and
animal wastes
• Harmful Effects: Disease
7. Major
Categories of
Water Pollutants
OXYGEN-DEMANDING WASTES
• Examples: Organic waste such as animal manure
and plant debris that can be decomposed by
aerobic (oxygen-requiring) bacteria
• Major Human Sources: Sewage, animal
feedlots, paper mills, and food processing
facilities
• Harmful Effects: Large populations of bacteria
decomposing these wastes can degrade water
quality by depleting water of dissolved oxygen.
This causes fish and other forms of oxygen-
consuming aquatic life to die.
8. Major Categories of Water Pollutants
INORGANIC CHEMICALS
• Examples: Water-soluble 1) acids, (2) compounds of toxic metals such as lead
(Pb),
• arsenic (As), and selenium Se), and (3) salts such as sodium chloride (NaCl)
in ocean water and fluorides (F–) found in some soils
• Major Human Sources: Surface runoff, industrial effluents, and household
cleansers
• Harmful Effects: Can (1) make fresh water unusable for drinking or
irrigation, (2) cause skin cancers and crippling spinal and neck damage (F–),
(3) damage the nervous system, liver, and kidneys (Pb and As), (4) harm fish
and other aquatic life, (5) lower crop yields, and (6) accelerate corrosion of
metals exposed to such water.
9. Major Categories of
Water Pollutants
ORGANIC CHEMICALS
• Examples: Oil, gasoline, plastics, pesticides, cleaning
solvents, detergents
• Major Human Sources: Industrial effluents, household
cleansers, surface runoff from
• farms and yards
• Harmful Effects: Can (1) threaten human health by causing
nervous system damage (some pesticides), reproductive
disorders (some solvents), and some cancers (gasoline, oil,
and some solvents) and (2) harm fish and wildlife.
10. Major Categories of Water Pollutants
PLANT NUTRIENTS
• Examples: Water-soluble compounds containing nitrate (NO3
–), phosphate (PO4
3–), and
ammonium (NH4
+) ions
• Major Human Sources: Sewage, manure, and runoff of agricultural and urban fertilizers
• Harmful Effects: Can cause excessive growth of algae and other aquatic plants, which die, decay,
deplete water of dissolved oxygen, and kill fish. Drinking water with excessive levels of nitrates
lowers the oxygen-carrying capacity of the blood and can kill unborn children and infants
(“bluebaby syndrome”).
11. Major Categories of Water Pollutants
SEDIMENT
• Examples: Soil, silt
• Major Human Sources: Land erosion
• Harmful Effects: Can (1) cloud water and reduce photosynthesis, (2) disrupt aquatic food
webs, (3) carry pesticides, bacteria, and other harmful substances, (4) settle out and destroy
feeding and spawning grounds of fish, and (5) clog and fill lakes, artificial reservoirs, stream
channels, and harbors.
12. Major Categories of
Water Pollutants
RADIOACTIVE MATERIALS
• Examples: Radioactive isotopes of iodine,
radon, uranium, cesium, and thorium
• Major Human Sources: Nuclear and coal-
burning power plants, mining and processing of
uranium and other ores, nuclear weapons
production, natural sources
• Harmful Effects: Genetic mutations,
miscarriages, birth defects, and certain cancers
13. Major Categories
of Water
Pollutants
HEAT (THERMAL POLLUTION)
• Examples: Excessive heat
• Major Human Sources: Water cooling of electric power plants and
some types of industrial plants. Almost half of all water withdrawn
in the United States each year is
• for cooling electric power plants.
• Harmful Effects: Lowers dissolved oxygen levels and makes
aquatic organisms more vulnerable to disease, parasites, and toxic
chemicals. When a power plant first opens or shuts down for repair,
fish and other organisms adapted to a particular temperature range
can be killed by the abrupt change in water temperature—known as
thermal shock.
14.
15. Common Diseases
Transmitted to
Humans
Through
Contaminated
Drinking Water
Type of
Organism
Bacteria
Viruses
Parasitic protozoa
Parasitic worms
Disease
Typhoid fever
Cholera
Bacterial dysentery
Enteritis
Infectious hepatitis
Amoebic dysentery
Giardiasis
Schistosomiasis
Effects
Diarrhea, severe vomiting, enlarged spleen,
inflamed intestine; often fatal if untreated
Diarrhea, severe vomiting, dehydration; often
fatal if untreated
Diarrhea; rarely fatal except in infants
without proper treatment
Severe stomach pain, nausea, vomiting;
rarely fatal
Fever, severe headache, loss of appetite,
abdominal pain, jaundice, enlarged liver;
rarely fatal but may cause permanent liver
damage
Severe diarrhea, headache, abdominal pain,
chills, fever; if not treated can cause liver
abscess, bowel perforation, and death
Diarrhea, abdominal cramps, flatulence,
belching, fatigue
Abdominal pain, skin rash, anemia, chronic
fatigue, and chronic general ill health
19. Effects on
human life
Mercury
• Mercury is a naturally occurring element that is found
in air, water and soil.
• Exposure to mercury – even small amounts – may
cause serious health problems and is a threat to the
development of the child in utero and early in life.
• Mercury may have toxic effects on the nervous,
digestive and immune systems, and on lungs, kidneys,
skin and eyes.
• People are mainly exposed to methylmercury, an
organic compound, when they eat fish and shellfish
that contain the compound.
• Methylmercury is very different to ethylmercury.
Ethylmercury is used as a preservative in some
vaccines and does not pose a health risk
20. Effects on
human life
Minamata disease
• Minamata disease, sometimes referred
to as Chisso-Minamata disease, is a
neurological disease caused by severe
mercury poisoning.
• Signs and symptoms include ataxia,
numbness in the hands and feet,
general muscle weakness, loss of
peripheral vision, and damage to
hearing and speech. In extreme cases,
insanity, paralysis, coma, and death
follow within weeks of the onset of
symptoms. A congenital form of the
disease can also affect fetuses in the
womb.
• Minamata disease was first discovered
in the city of Minamata, Kumamoto
Prefecture, Japan, in 1956. It was
caused by the release of
methylmercury in the industrial
wastewater from a chemical factory
owned by the Chisso Corporation,
which continued from 1932 to 1968.
21. Effects on
human life
Cadmium
• It accumulates in various body parts like
liver, kidney and thyroid gland.
• It causes vomiting, diarrhea, cramps,
hypertension, bon disorder and cancer of
lungs and liver.
• Itai-itai- a painful disease of bones and
joints
• Cadmium occurs naturally in zinc, in lead
and copper ores, in coal and other fossil
fuels, in shales and is released during
volcanic action.
• These deposits can serve as sources to
ground and surface waters, especially when
in contact with low total dissolved solids
(TDS) and acidic waters
22. Effects on
human life
Lead
• The most common sources of lead in
drinking water are lead pipes, faucets, and
plumbing fixtures.
• Certain pipes that carry drinking water
from the water source to the home may
contain lead. Household plumbing fixtures,
welding solder, and pipe fittings made prior
to 1986 may also contain lead.
• Adults exposed to lead can suffer from:
Cardiovascular effects, increased blood
pressure and incidence of hypertension.
Decreased kidney function. Reproductive
problems (in both men and women)
23.
24.
25. Groundwater Pollution: Causes
Coal strip mine
runoff
Pumpi
ng well
Waste lagoon
Acciden
tal spills
Groundw
ater flow
Confined aquifer
Discharge
Leakage from
faulty casing
Hazardous waste injection well
Pesticides
Gasoline
station
Buried gasoline and
solvent tank
Sewer
Cesspool
septic tank
De-icing
road salt
Water
pumping well
Landfill
• Low flow rates
• Few bacteria
• Low Oxygen
• Cold Temperatures
27. Groundwater Pollution
Fluorosis:
• Dental Fluorosis: It is a developmental disturbance of
dental enamel which is caused by excessive exposure
to high concentration of fluoride during tooth
development. In severe form, it can cause drown
stains, pitting or mottling of enamel.
• Skeletal Fluorosis: It is a bone disease caused by
excessive consumption of fluoride. In advance stage, it
causes pain and damage to bones and joints.
28. Methemoglobinemia:
• Excess of nitrate reacts with hemoglobin to form
methemoglobin, which has decreased oxygen carrying
capacity.
• This condition is called Methemoglobinemia or blue
baby syndrome.
• In adults the disorder causes breathlessness, nausea
and drowsiness.
Groundwater Pollution
29. Black foot disease:
• Excess of arsenic in drinking water causes repeated
diarrhea, thickening and pigmentation of skin,
inflammation of peripheral nerves and lungs and skin
cancer.
• Chronic exposure to arsenic caused black foot disease
in Taiwan in which blood vessels in the lower limbs
are severely damaged resulting in progressive
gangrene.
Groundwater Pollution
32. Groundwater Pollution Prevention
Monitor aquifers
Leak detection systems
Strictly regulating hazardous waste disposal
Store hazardous materials above ground
Find less hazardous substitutes
33. Groundwater Pollution
• Pump nanoparticles of
inorganic compounds to
remove pollutants (may be the
cheapest, easiest, and most
effective method but is still
being developed)
• Find substitutes for toxic
chemicals
• Keep toxic chemicals out of the
environment
• Install monitoring wells near landfills
and underground tanks
• Require leak detectors on
underground tanks
• Ban hazardous waste disposal in
landfills and injection wells
• Inject microorganisms to
clean up contamination (less
expensive but still costly)
• Store harmful liquids in
aboveground tanks with leak
detection and collection systems
Prevention Cleanup
• Pump to surface, clean,
and return to aquifer
(very expensive)
35. Coastal Water Pollution
Prevention Cleanup
• Ban dumping of wastes and
sewage by maritime and
cruise ships in coastal waters
• Reduce input of toxic pollutants
• Separate sewage and
storm lines
• Regulate coastal
development
• Recycle used oil
• Require double hulls for oil
tankers
• Require at least secondary
treatment of coastal sewage
• Use wetlands, solar-aquatic, or
other methods to treat sewage
• Sprinkle nanoparticles over
an oil or sewage spill to
dissolve the oil or sewage
without creating harmful
byproducts (still under
development)
• Protect sensitive areas from
development, oil drilling, and
oil shipping
• Ban ocean dumping of sludge and
hazardous dredged material
• Improve oil-spill cleanup
capabilities
36. • Sewage treatment (or domestic wastewater
treatment, municipal wastewater treatment) is a
type of wastewater treatment which aims to
remove contaminants from sewage.
• Sewage contains wastewater from households and
businesses and possibly pre-treated industrial
wastewater.
• Physical, chemical, and biological processes are
used to remove contaminants and produce treated
wastewater (or treated effluent) that is safe enough
for release into the environment.
• A by-product of sewage treatment is a semi-solid
waste or slurry, called sewage sludge.
• The sludge must undergo further treatment before
being suitable for disposal or application to land.
• The term "sewage treatment plant" is often used
interchangeably with the term "wastewater
treatment plant
SEWAGE TREATMENT
PLANT
37. Primary and Secondary Sewage
Treatment
Raw sewage
from sewers
Bar screen Grit chamber Settling tank Aeration tank Settling tank
Chlorine
disinfection tank
Sludge
Sludge
digester
Activated sludge
Air pump
(kills
bacteria)
To river,
lake,
or ocean
Sludge drying bed
Disposed of
in landfill or
ocean or
applied to
cropland,
pasture, or
rangeland
Primary Secondary
40. Control of
Water
Pollution
• Prevent groundwater contamination
• Greatly reduce nonpoint runoff
• Reuse treated wastewater for irrigation
• Find substitutes for toxic pollutants
• Work with nature to treat sewage
• Practice four R's of resource use
(refuse, reduce, recycle, reuse)
• Reduce resource waste
• Reduce air pollution
• Reduce poverty
• Compliance with water laws
41. Control of Water
Pollution
• Fertilize your garden and yard plants
with manure or compost instead of
commercial inorganic fertilizer.
• Minimize your use of pesticides.
• Never apply fertilizer or pesticides
near a body of water.
• Grow or buy organic foods.
• Compost your food wastes.
• Do not use water fresheners in toilets.
• Do not flush unwanted medicines
down the toilet.
• Do not pour pesticides, paints,
solvents, oil, antifreeze, or other
products containing harmful
chemicals down the drain or onto the
ground.
